ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Unknown
    Berlin ; Heidelberg : Springer
    Keywords: Fehlersuche ; Geophysikalische Methoden ; entropy ; environment ; error analysis ; exploration ; geophysical methods ; geophysics ; inversion ; modeling ; signal processing
    Description / Table of Contents: Introduction / Pages 1-32 --- Interpretation using nomograms / Pages 33-47 --- Linear parameters / Pages 49-114 --- Non-linear parameters / Pages 115-173 --- Maximum likelihood and maximum entropy / Pages 175-193 --- Analytic inversion / Pages 195-211 --- Advanced inversion methods / Pages 213-227 --- Error analysis / Pages 229-243 --- Parallel computation in modelling and inversion / Pages 245-255
    Pages: Online-Ressource (262 Seiten) , Illustrationen, Diagramme
    ISBN: 9783540472636
    Language: English
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    Geophysical Consulting GmbH (GeCon)
    In:  Kiel, Geophysical Consulting GmbH (GeCon), vol. 18, no. Publ. No. 12, pp. 9, (ISBN 0-521-35367-X, ISBN 0-521-79836-1 paper)
    Publication Date: 1990
    Keywords: Seismics (controlled source seismology) ; SH waves ; environment ; waste ; disposal
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    Springer Verlag
    In:  Berlin, Springer Verlag, vol. 20, no. 1, pp. 662-664, (ISBN 1-58488-320-0)
    Publication Date: 1994
    Keywords: Textbook of geology ; Textbook of geophysics ; Applied geophysics ; environment ; Altlasten ; climatic ; changes
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1572-8773
    Keywords: heavy metals ; maternal blood ; umbilical cord blood
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Concentrations of lead, cadmium, methylmercury and total mercury were measured in maternal and umbilical cord blood using graphite atomic absorption spectrometry. Two essential metals, copper and zinc, were also determined using ion chromatography. Lead, copper and zinc were found to be lower in the cord blood, whereas methylmercury and total mercury were higher in cord blood than in maternal blood. Little differences were noted for cadmium in maternal and cord blood. Significant positive correlations were observed between the concentrations in maternal and cord blood with regard to lead (correlation coefficient, r = 0.44), copper (r = 0.34), zinc (r = 0.29), methylmercury (r = 0.44) and total mercury (r = 0.58). These results suggest that, like essential metals, most heavy metals can move rather freely across the human placenta. The potential health effects of heavy metal transfer from mothers to young infants cannot be discounted.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1572-8773
    Keywords: fish liver ; heavy metals ; metallothionein inducibility ; subcellular ion balance ; zinc pretreatment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Determination of metal levels (copper, zinc, cadmium, silver and mercury) in soluble and insoluble fractions of liver homogenates has been performed after 7 days exposure of carps (Cyprinus carpio) to moderate concentrations of cadmium, silver and mercury in water. Metallothionein (MT) levels have been quantified by a polarographic method before and after the contamination and a subsequent decontamination phase (7 days). The influence of pretreatment by zinc (7 days) has also been evaluated. MT level variations have been interpreted as having regard to inter-related flows of metal between subcellular fractions. Special interest has been focused on heat-stable compound (HSC)-bound heavy metal flows within the cytosol, taking in account that MT is the major component of these ligands. Our data showed differences between the ability of metals to bind cytosolic ligands and HSCs, and their respective potency for MT induction in liver. Regardless of pretreatment, mercury gave the highest increase of liver MT, but the MT level decreased during the decontamination step, especially after pretreatment by zinc. Cadmium and silver gave similar increases, but a significant difference with the control appeared only after the decontamination step with cadmium, while 1 week of contamintion was enough for silver. However, silver binding with MT was achieved only by the end of the decontamination step, while cadmium depicted the highest ratio for HSC-bound toxic metals after the contamination. Our experimental conditions gave the following order of potency for MT induction in liver: mercury ≫ silver 〉 cadmium 〉 zinc. Results are discussed comparatively with data obtained with carp gills.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1572-8773
    Keywords: Drosophila melanogaster ; evaluation ; neurotoxicity ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Heavy metals cause irreversible neurobehavioral damage in many developing mammals, but the mechanisms of this damage are unknown. The influence of three heavy metal compounds, triethyllead chloride, lead acetate and cadmium chloride, on lethality, development, behavior and learning was studied using the fruit fly,Drosophila melanogaster. This animal was used because it allows hundreds of subjects to be assayed very easily in individual experiments and because it is a system in which toxicological questions might be answered by using the techniques of modern molecular genetics. When triethyllead chloride, lead acetate or cadmium chloride was placed in the medium, the larval LC50 (± standard error) was found to be 0.090±0.004, 6.60±0.64 and 0.42±0.04mm, respectively. Each of the tested compounds produced a dose-related delay in development. In particular, they caused a delay in the development of larvae to pupae. When larvae were reared on medium containing triethyllead chloride (0.06mm), lead acetate (3.07mm) or cadmium chloride (0.11mm), phototaxis, locomotion and learning were not inhibited. Since significant neurobehavioral effects were not observed under the experimental conditions used,Drosophila does not appear to be an appropriate animal for the genetic dissection of such effects of heavy metals during development.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1572-8773
    Keywords: Anabaena flos-aquae ; chlorophyll a ; fluorescence emission ; heavy metals ; Hill activity ; photosystem II ; phycobilisomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The effect of equimolar concentrations of Hg2+ and Cd2+ on the whole cell absorption spectra, absorption spectra of the extracted phycocyanin (PC) and fluorescence emission spectra of phycobilisomes (PBS) was investigated in the cells of Anabaena flos-aquae. The PC component of the PBS was found to be extremely sensitive to the Hg2+ rather than the Cd2+ ions. Further, the results showed that Hg2+ and Cd2+ induced decrease in the rate of Hill activity (H2O - DCPIP) was partially restored by the electron donor NH2OH, not by the diphenyl carbazide. Similarly, chlorophyll a fluorescence emission in the presence of metals showed that addition of NH2OH could effectively reverse the metal induced alterations in the fluorescence emission intensity. These results, together, suggested that Hg2+ and Cd2+ caused damage to the photosystems (PS) II reaction center. However, a relatively higher stimulation of the chlorophyll a emission at 695 nm with a red shift of 4.0 nm in the presence of Hg2+, and Cd2+ induced preferential decrease in the emission intensity at 676 nm as compared with the peak at 695 nm were indicative of the differential action of Hg2+ and Cd2+ on the PS II.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Transportation 20 (1993), S. 1-19 
    ISSN: 1572-9435
    Keywords: automobile ; pricing ; sustainable future ; environment ; public transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract In its relatively short life, the automobile has provided a level of mobility unlikely to have been feasible with a reliance on conventional forms of land based public transport. It has contributed in both a positive and negative way to the quality of life, transforming our cities, our way of life, and giving us a greater command over time and space. Concern over the undesirable social and environmental impacts has increased over time, with calls for governments to take action to reduce the automobile's dominant role. New investment in fixed-track public transport and bus priority systems together with strategies to discourage travel have been proposed to improve accessibility and to aid in cleaning up the physical environment. This paper reviews some of the issues facing society as it works to identify policies to achieve an economically and environmentally sustainabie future. There is a need for a broader set of policies to facilitate alternative land use-transport lifestyles while facing appropriate pricing signals. Some of the key issues are adjustments in the relative prices of location and transport, spatial incentives to make public transport economically viable (i.e. changing urban densities, zoning/incentive changes to allow more infill), road pricing (i.e. charging cars the economic cost of using the roads), new information technology systems (e.g. IVHS) to improve the efficiency and effectiveness of transport infrastructure, major improvements in the fuel efficiency of fossil fuelled vehicles, and alternative-fuelled vehicles (“clean-air vehicles”).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Annals of operations research 54 (1994), S. 97-117 
    ISSN: 1572-9338
    Keywords: Modelling ; interconnection ; side payments ; game theory ; environment ; transboundary pollution ; multiple objective games ; repeated games ; tensor games ; tradeoff ; Pareto equilibrium ; Nash equilibrium ; Folk theorem ; prisoners' dilemma ; JEL C70 ; Q28
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract Some features of international environmental problems are considered. A basic problem is to induce countries to adopt a cooperative approach. One of the instruments to induce countries to cooperate is an exchange of concessions in fields of relative strengths, such as swapping trade concessions for cooperation on international environmental problems. This instrument will be modelled in this paper with tensor games. Both tradeoff and non-tradeoff tensor games will be addressed, with emphasis on tradeoff tensor games with linear strict weights. The relationship between the Pareto equilibria of a non-tradeoff tensor game and the Nash equilibria of the associated tradeoff tensor games will be studied. Due to structural similarities between tensor games and repeated multiple objective games, some attention will also be paid to the latter. Relationships between objects related to Folk theorems for the tradeoff tensor game with completely additive weights and the corresponding objects for its constituting isolated games will be studied. Since many international environmental problems have prisoners' dilemma characteristics, it is analyzed how interconnection may enhance cooperation in prisoners' dilemma games.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1572-879X
    Keywords: Zeolitic catalysts ; transition metal ions ; nickel ; computation ; environment ; EXAFS ; modelling catalysts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Computer modelling techniques are used to investigate the local structure of the zeolite framework around Ni2+ ions in the SI sites of Ni exchanged zeolite-Y. Our calculations show that there are pronounced inward relaxations (0.4 Å–0.6 Å) of the surrounding oxygen ions. The results allow a detailed rationalisation of recent EXAFS and diffraction studies on this zeolite.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 48 (1992), S. 955-970 
    ISSN: 1420-9071
    Keywords: Bioaccumulation ; bioconcentration ; BCF ; pesticides ; ecotoxicology ; compartment models ; QSAR ; food chain ; atrazine ; lindane ; DDT ; DDE ; PCB ; heavy metals ; plants ; earthworms ; birds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The fate of environmental pollutants — the various isotopes of elements, and inorganic or organic compounds — is a fundamental aspect of ecology and ecotoxicology, and bioaccumulation is a phenomenon often discussed in this context. Human activities have drastically altered natural concentrations of many substances in the environment and added numerous new chemicals. An understanding of the processes of bioaccumulation is important for several reasons. 1) Bioaccumulation in organisms may enhance the persistence of industrial chemicals in the ecosystem as a whole, since they can be fixed in the tissues of organisms. 2) Stored chemicals are not exposed to direct physical, chemical, or biochemical degradation. 3) Stored chemicals can directly affect an individual's health. 4) Predators of those organisms that have bioaccumulated harmful substances may be endangered by food chain effects. While former theories on the processes of bioaccumulation focused on single aspects that affect the extent of accumulation (such as the trophic level within the food chain or the lipophilicity of the chemical), modern theories are based on compartmental kinetics and the integration of various environmental interactions. Concepts include results from quantitative structure-activity relationships (QSAR), pharmacokinetics, ecophysiology and general biology, molecular genetic aspects and selection, and finally the structure of communities and man-made alterations in them.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Aquatic sciences 55 (1993), S. 281-290 
    ISSN: 1420-9055
    Keywords: Minerals ; dissolution kinetics ; inhibition ; aluminum ; polynuclear ; formation ; heavy metals ; complexation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Dissolution kinetics of minerals can be significantly inhibited by re-adsorbed aluminum. As a consequence of neutralization, polynuclear Al species may be formed in soil solutions. While re-acidification leads to decomposition of the polymers, further neutralization induces the formation of aggregates. The complexation of heavy metal ions with dissolved and aggregated Al polymers is illustrated as a potential factor influencing the chemical speciation of heavy metals in soils.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    ISSN: 1572-8773
    Keywords: Anabaena flos-aquae ; carbon fixation ; carbonic anhydrase ; heavy metals ; Hill activity ; oxygen evolution ; proton efflux
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Light induced proton efflux in intact cells ofAnabaena flos-aquae is inhibited by the heavy metals Hg2+ and Cd2+. Furthermore, Hg2+ and Cd2+ reduced the14CO2 fixation, oxygen evolution and carbonic anhydrase activity responsible for H+ efflux.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    ISSN: 1572-8773
    Keywords: cell wall extensibility ; heavy metals ; Impatiens balsamina ; stem cell elongation ; turgor pressure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Elongation growth rate of stem cells of Impatiens balsamina was inhibited by the heavy metals Pb2+, Cd2+ and Zn2+ due to their suppression on cell wall extensibility. Effective turgor was also inhibited by Pb2+ and Cd2+ but it played a secondary role in reducing the stem cell elongation growth rate. The major rate-limiting factor for cell elongation growth was the cell wall extensibility. Furthermore, Cd2+ was found to be more toxic than Pb2+, while Pb2+ was more toxic than Zn2+.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    ISSN: 1436-5073
    Keywords: speciation ; improvement ; quality ; analysis ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The release of some organometallic compounds and other chemical forms of elements in the environment has led to great international concern because of their high toxicity. The validation of the analytical techniques became of paramount importance which led the Community Bureau of Reference (BCR) to decide on the organisation of a series of projects for the improvement of the quality of speciation analyses. In addition, it was found useful to discuss thoroughly the different sources of error likely occurring in speciation analyses and a workshop was organized for this purpose; the aim of this workshop was to discuss the state of the art of speciation determinations, to define use, applicability and necessity of determinations of element species, to investigate where limitations exist and discuss the work necessary to overcome these and to detect where techniques have sufficiently been developed to produce reliable and valuable results. This paper presents the organization of the workshop, its main issue and describe the state of the current BCR projects on speciation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Microchimica acta 111 (1993), S. 207-213 
    ISSN: 1436-5073
    Keywords: mercury ; cold vapour atomic absorption spectrometry ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A continuously operating monitoring method for total mercury at sub-ng/ml level in environmental and biological samples by cold vapour atomic-absorption spectrometry with NaBH4 as a reductant was developed. The mercury vapour generator and absorption cell closed-end by quartz were used in this study. The detection limit (S/N = 3) and relative standard deviation of 12 determinations of 10 ng/ml Hg(II) were 0.11 ng/ml and 1.1%, respectively. The range of standard calibration curve was 0–50 ng/ml Hg, The proposed method was successfully applied to the completely continuous monitoring of total mercury in waste water, sediments and pork liver.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Biodegradation 3 (1992), S. 161-170 
    ISSN: 1572-9729
    Keywords: bioremediation ; cadmium ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Cadmium pollution arises mainly from contamination of minerals used in agriculture and from industrial processes. The usual situation is of large volumes of soil and water that are contaminated with low — but significant — concentrations of cadmium. Therefore, detoxification of the polluted water and soil involves the concentration of the metal, or binding it in a way that makes it biologically inert. Cadmium is one of the more toxic metals, that is also carcinogenic and teratogenic. Its effects are short term, even acute (diseases like Itai-itai), or long term. The long term effects are intensified due to the fact that cadmium accumulates in the body. This paper describes a study involving several hundred cadmium-resistant bacterial isolates. These bacteria could be divided into three groups—the largest group consisted of bacteria resistant to cadmium by effluxing it from the cells. The bacteria of the other two groups were capable of binding cadmium or of detoxifying it. We concentrated on one strain that could bind cadmium very efficiently, depending on the bacterial biomass and on the pH. This strain could effectively remove cadmium from contaminated water and soil.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Journal of intelligent and robotic systems 8 (1993), S. 267-284 
    ISSN: 1573-0409
    Keywords: Intelligent control ; simulation ; agriculture ; robotics ; melon harvesting ; intelligent systems ; planning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract An intelligent control system for an agricultural robot which performs in an uncertain and unstructured environment was modelled as distributed, autonomous computing modules that communicate through globally accessible blackboard structures. The control architecture was implemented for a robotic harvester of melons. A CAD workstation was used to plan, model, simulate and evaluate the robot and gripper motions using 3-D, real-time animation. The intelligent control structure was verified by simulating the dynamic data flow scenarios of melon harvesting. Control algorithms were evaluated on measured melon locations. Picking time was reduced by 49% by applying the traveling salesman algorithm to define the picking sequence. Picking speeds can be increased by a continuous mode of operation. However, this decreases harvest efficiency. Therefore, an algorithm was developed to attain 100% harvest efficiency by varying the vehicle's forward speed. By comparing different motion control algorithms through animated visual simulation, the best was selected and thereby the performance improved.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1573-0417
    Keywords: diatoms ; pollen ; chrysophytes ; heavy metals ; acidification ; land-use ; Norway ; pH changes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Lakes perched on hill-tops have very small catchments. Their water chemistry is largely influenced by the chemical composition of precipitation and by the underlying bedrock geology. They are ideal sites for testing the hypothesis that land-use and associated soil changes are a major cause of recent lake acidification. On this hypothesis, hill-top lakes in SW Norway are predicted not to show any recent lake acidification because, by their very nature, the chemistry of such lakes is little influenced by land-use or soil changes. Palaeolimnological analyses of diatoms and chrysophytes show that prior to ca. 1914 the two hill-top lakes investigated were naturally acid with reconstructed lake-pH values of at least 4.8–5.1. Since ca. 1914 lake pH values declined to ca. 4.5–4.7. These results contradict the land-use hypothesis. All the available palaeolimnological evidence (diatoms, chrysophytes, pollen, sediment geochemistry, carbonaceous particles) is consistent with the acid-deposition hypothesis. In the absence of any evidence to support the land-use hypothesis as a primary cause of recent lake acidification and in the light of several independent refutations, it is perhaps time to put the land-use hypothesis for recent lake acidification to rest.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 37 (1994), S. 1-22 
    ISSN: 1573-0867
    Keywords: animal slurries and manures ; applications to soils ; carbon- ; nitrogen- ; phosphorus ; contamination ; crop production ; dissemination ; hazardous organics ; heavy metals ; inputs ; macro- and micronutrients ; pathogens ; sewage sludges ; survival- ; transfer- ; transport and adsorption rates in soils
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The European Community is producing annually about 300 × 106 tons of sewage sludges as well as about 150, 950,160 and 200 tons of domestic, agricultural, industrial and other wastes (street litter, dead leaves etc.). About 20–25% of the German sewage sludges, which contain in average about 3.8,1.6, 0.4, 0.6, 5.3% DM−1 N, P, K, Mg and Ca, 202, 5, 131, 349, 53, 3 and 1446 mg kg−1 DM Pb, Cd, Cr, Cu, Ni, Hg, Zn as well as ca. 37 and 5 mg kg−1 Dm polychlorinated hydrocarbons and biphenyls, are recycled annually as fertilizer. In addition environmental impacts on the arable land of Germany may derive from 76,19.2, 64.7, 33.6, 7.8 and 0.1 kg ha−1 a−1 of N, P, K, Ca, Mg and Cu added as animal manures. Besides heavy metals and hazardous organics pathogens are disseminated with organic wastes. Crop production and soil fertility generally profit from the considerable amounts of plant nutrients and carbon in sewage sludges, animal slurries and manures, but the physicochemical soil properties, the composition of microbial, faunal and plant communities as well as the metabolic processes in the soil-, rhizo- and phyllosphere are changed by organic manuring. Consequences for the soil carbon-, nitrogen-and phosphorus-cycle are discussed. Impacts of heavy metals and hazardous organics on the soil biomass and its habitat as well as on transport mechanisms and surival times of disseminated pathogens in soils are reviewed with emphasis on the German situation. A proposal for future strategies (landscape recycling) is made.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 26 (1990), S. 189-196 
    ISSN: 1573-0867
    Keywords: Soil analysis ; nutrient diagnosis ; nutrient potential ; nutrient capacity ; transfer coefficient ; soil classification ; fertility ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The limitations of various methods of soil analysis are discussed. The total analysis of an element gives a simple figure which is, however, useless for diagnositic purposes since nutrient availability differs in various soil fractions. Since the transfer coefficient applied to soil pollutants is based on total soil analysis, it also has no diagnostic value. The use of soil extractants is empirical and is only as good as the calibration curve. It should, therefore, only be applied to those soils for which a good calibration curve has been shown to exist. The scientific approach of Schofield in proposing nutrient potentials is basically correct, but it fails to fully characterize the nutrient availability in soils. Difficulties are of a fundamental nature or are soil or plant related. A possible means of improvement may be a soil classification which is geared towards soil fertility. Soils which react similarly to nutrients should be combined in classification units. For these units, detailed information on the reaction behavior must be obtained. A few simple analyses might suffice to show how a specific field fits into this reaction pattern. Based on the thorough knowledge of the soil (especially its reaction pattern) it is then possible to quantitatively predict for a specific crop plant the changes that occur when nutrients are removed by uptake or added by fertilization.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 26 (1990), S. 209-215 
    ISSN: 1573-0867
    Keywords: Greenhouse gases ; nitrous oxide ; ammonia ; nitrogen oxides ; environment ; pollution ; nitrogen fertilizers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In recent years concern has grown over the contribution of nitrogen (N) fertilizers to the environmental problems of nitrate pollution of waters and the pollution of the atmosphere with nitrous oxide, other oxides of nitrogen, and ammonia. These gases potentially contribute to the ‘greenhouse effect’ or global heating because of their increasing concentrations in the atmosphere and to the destruction of the stratospheric ozone layer, which protects the earth from ultraviolet radiation. In light of these concerns, proposals to mitigate these problems have been considered, and others will be forthcoming. When they have been used in high amounts, fertilizers and animal manures have created problems of nitrate pollution. Nitrous oxide (N2O) is a greenhouse gas and may also contribute to the destruction of the stratospheric ozone when it is converted to nitric oxide. N2O is primarily produced in the biological processes of nitrification and denitrification. Nitric oxide and nitrogen dioxide are also produced in biological processes and are important in atmospheric reactions in the troposphere and stratosphere. There is little indication that N fertilizers contribute very much to the production of nitrous oxide. More research is needed to characterize and measure the emissions of the oxides of nitrogen and ammonia and to make better estimates of global emissions based on process-related models. More efforts to increase the efficiency of nitrogen fertilizer use through modifications or use of inhibitors of biological processes as well as better management of rates, timing, and incorporation are needed to ensure increased food production while conserving natural resources.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 39 (1994), S. 167-178 
    ISSN: 1573-0867
    Keywords: environment ; fertiliser ; optimum ; price ratio ; prices ; restrictions ; sugar beet
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Although excessive application of fertiliser has been commonplace, optimisation, as well as more limited use, is increasingly topical because of environmental and economic considerations that provide an impetus for either direct or price-induced restriction of fertiliser use. In this context, optimum N, P and K inputs, yields of sugar and yield deficits were calculated for sugar beet for current nutrient prices, multiples of 1.5, 2, 3 and 5 times current prices and for a range from 0% to 150% of the current optimum for each of four soil-fertility index categories. In terms of the optimum input, N was more impervious to price increase than P or K. For example, on low-fertility index 1 soils, reduction of inputs to circa 75% of current optimum required increases of 200% for N, 50% for P and 100% for K. Increases of 20–30%, representative of fertiliser taxes, had little impact. Variation in product price had a greater effect than nutrient price, as indicated by the exponential relationship between their proportional changes for similar effects on the price ratio, and the combined effect of small changes in each was appreciable. All nutrient-price increases induced yield deficits in the order P 〉 K 〉 N. The aggregate financial effect on yield deficit and net nutrient cost, i.e. on gross margin, was in the order N 〉 K 〉 P for very large price increases, with little difference between nutrients for increases of 100% or less. Mean effects of 100% price increases were yield deficits (%) of 0.3 to 0.4 for N, 0.7 to 2.3 for P and 0.4 to 1.3 for K, depending on index category, and reductions in gross margins (%) of 5.1 to 5.4 at index 1 and 0.7 to 1.6 at index 4 depending on the nutrient. Direct input restriction to 75% or 50% of optimum had negligible financial effects, with the exception of the 50% restriction for N. Voluntary restriction of fertiliser inputs for sugar beet, therefore, would be both environmentally and financially efficient compared with price-induced restriction at the level of a fertiliser tax. Since distribution of yield deficits was right-skewed, a two-parameter gamma distribution was used to determine the probability of exceeding deficits of 5% and 3%. Only extreme price increases or input restrictions, or excessive use in the case of N, resulted in deficit frequencies of significant proportions; comparatively, P and K were more sensitive to price increase and N more sensitive to direct restriction. Complete input restriction on high-fertility, index 4, soils breached the acceptable tolerance of deficits 〉5% for N and K but not for P. For the latter, the results implied a possible conflict between environmental good-practice and the achievement of nutrient reserves required for highest yield.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Electronic Resource
    Electronic Resource
    Springer
    Natural hazards 6 (1992), S. 109-129 
    ISSN: 1573-0840
    Keywords: Drought ; agriculture ; hydrology ; monitoring ; research
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geography , Geosciences
    Notes: Abstract The 1988 drought conditions, which prevailed over the southern portion of the Canadian prairie provinces, resulted in severe impacts on agriculture, water resources, forestry, and waterfowl production. In this paper, the climatological aspects of the drought are reviewed and the impacts of the drought are described. In addition, a number of the environmental factors that may have aggravated the drought's impacts are discussed. Processes contributing to the 1988 drought are considered in terms of their scales, relative importance and possible effects. It was evident from the information needs of government agencies and private businesses which had to cope with the effects of the 1988 drought, that studies are needed to effectively monitor drought and adjust to its impacts. In this paper, these needs are discussed; several specific hypotheses concerning drought-related processes are advanced and a framework for addressing the scientific aspects of droughts on the Canadian prairies is proposed. It is anticipated that many of these identified research needs and opportunities are applicable to other drought-prone areas of the world.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Journal of fusion energy 12 (1993), S. 145-148 
    ISSN: 1572-9591
    Keywords: tritium ; transport ; monitoring ; environment ; model ; validation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Environmental tritium concentrations will be measured near the Tokamak Fusion Test Reactor (TFTR) to help validate dynamic models of tritium transport in the environment. For model validation the database must contain sequential measurements of tritium concentrations in key environmental compartments. Since complete containment of tritium is an operational goal, the supplementary monitoring program should be able to glean useful data from an unscheduled acute release. Portable air samplers will be used to take samples automatically every 4 hours for a week after an acute release, thus obtaining the time resolution needed for code validation. Samples of soil, vegetation, and foodstuffs will be gathered daily at the same locations as the active air monitors. The database may help validate the plant/soil/air part of tritium transport models and enhance environmental tritium transport understanding for the International Thermonuclear Experimental Reactor (ITER).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    Springer
    Journal of fusion energy 12 (1993), S. 149-156 
    ISSN: 1572-9591
    Keywords: environment ; tritium ; activation products ; dose calculations ; NET, ITER
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract In view of public acceptance and the licensing procedure of projected fusion reactors, the release of tritium and activation products during normal operation as well as after accidents is a significant safety aspect. Calculations have been performed under accidental conditions for unit releases of corrosion products from water coolant loops, of first wall erosion products including different coating materials, and of tritium in its chemical form of tritiated water (HTO). Dose assessments during normal operation have been performed for corrosion products from first wall primary coolant loop and for tritium in both chemical forms (HT/HTO). The two accident consequence assessment (ACA) codes UFOTRI and COSYMA have been applied for the deterministic dose calculations with nearly the same input variables and for several radiological source terms. Furthermore, COSYMA and NORMTRI have been applied for routine release scenarios. The paper analyzes the radioation doses to individuals and the population resulting from the different materials assumed to be released in the environment.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    Springer
    Pure and applied geophysics 141 (1993), S. 125-137 
    ISSN: 1420-9136
    Keywords: Automatic equipment ; groundwater radon ; environment ; earthquake precursors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Prototype instrumentation, able to automatically measure groundwater radon content variations, is presented. The equipment is made of stainless steel and has spherical valves with automatic and pneumatic control. The deemanation of the gases from the water is obtained by evacuating a suitable expansion chamber. The instrumentation can make discrete sampling ranging from 1 per hour to 1 per 99 hours. The equipment was tested in the laboratory: the efficiency was measured by means of a266Ra solution. A mean value of (0.65±0.07) count/s/Bq was obtained. A calibration test was carried out by comparing countings from the automatic equipment with those obtained by the standard laboratory cell. Results of an operational check over a period of approximately one year indicate that variations in radon at the calibration site are attributable more to meteorological than to tectonic causes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 38 (1992), S. 2087-2093 
    ISSN: 1572-8943
    Keywords: environment ; paint-shop wastes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die untersuchten Lackier-Abfälle kommen aus Lackierereien metallurgischer Fabriken. Wegen ihrer hohen Toxizität und Entflammbarkeit werden sie für die natürliche Umgebung als besonders gefährlich eingestuft. Lackiererei-Abfälle können auf folgende Weise entsorgt werden: Verfestigung und Deponierung auf Ablagerungsplätzen Lagern in Sondermülldeponien Veraschung In diesem Artikel wird die physikochemische Zusammensetzung und die Thermoanalyse (DTA und TG) beider Lackiererei-Abfälle und ihrer Gemische mit verschiedenen Komponenten beschrieben. Die thermoanalytischen Messungen wurden in dynamischer Luftatmosphäre ausgeführt. Die Enthalpiewerte wurden anhand der Peakflächen der DTA Kurven berechnet. Die thermoanalytischen Angaben wurden weiterhin mit den kalorimetrischen Daten von einer Sauerstoffbombe verglichen.
    Notes: Abstract The paint-shop wastes under study originated from metallurgical factory painting houses. Displaying a high toxicity and flammability, they are classified as specifically hazardous to the natural environment. Paint-shop wastes can be disposed of in the following ways: solidification and deposition in sanitary landfills; storage on a special dumping ground; incineration. This paper presents the physicochemical composition and thermal analysis (DTA and TG) of paint-shop wastes and their mixtures with various components. Thermoanalytical measurements were carried out in a dynamic atmosphere of air. Enthalpies were calculated from the peak areas of the DTA curves. Thermoanalytical data were compared with calorimetric results obtained with an oxygen bomb.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 38 (1992), S. 973-979 
    ISSN: 1572-8943
    Keywords: environment ; solid industrial wastes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Wahl einer geeigneten und sicheren Entsorgung sollte auf breitangelegten physikalisch-chemischen Untersuchungen basieren. Thermoanalyse in Verbindung mit anderen Angaben, die eine Identifikation von Abfallstoffen ermöglichen, ermöglicht die Bestimmung des Masseverlustes zu einem beliebigen Zeitpunkt während der Zersetzungsreaktion sowohl die Charakterisierung der Verbrennungseigenschaften des Ab-falles. Es wird hier die physikalisch-chemische Zusammensetzung einiger Industrieabfälle beschrieben, die eine große Gefahr für die natürliche Umwelt darstellen. Folgende Abfallmaterialien wurden untersucht: Teerabfälle aus einigen Bereichen einer Koksfabrik Lackierabfälle aus einer Metallfabrik In dynamischer Luftatmosphäre wurden thermoanalytische Messungen durchgeführt, sowie anhand der Peakflächen der DTA-Kurven Enthalpiewerte errechnet. Die thermoanalytisch erhaltenen Angaben wurden mit den Werten aus einer Sauerstoffbombe verglichen. Eine Entsorgungsmethode für obengenannte Materialien wird empfohlen.
    Notes: Abstract The choice of an appropriate and safe disposal alternative should be based on the wide range of physicochemical examination thermal analysis in conjunction with other data enables identification of wastes, allows determination of weight losses at any stage of thermal decomposition and characterization of the combustible properties of wastes. In this paper the physicochemical composition of some industrial wastes, which create serious hazards to the natural environment is presented. The following waste materials were investigated: tar wastes from several departments of the coking plant paint-shop wastes from a metallurgical factory. Thermoanalytic measurements were carried out in the dynamic atmosphere of air. Enthalpic values were calculated from the peak areas of the DTA curves. Thermoanalytic data were compared with calorimetric results obtained from an oxygen bomb. The disposal methods for above-mentioned wastes are proposed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    Springer
    Journal of agricultural and environmental ethics 4 (1991), S. 1-13 
    ISSN: 1573-322X
    Keywords: ethanol ; food ; energy ; environment ; pollution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract Problems of fuel ethanol production have been the subject of numerous reports, including this analysis. The conclusions are that ethanol: does not improve U.S. energy security; is uneconomical; is not a renewable energy source; and increases environmental degradation. Ethanol production is wasteful of energy resources and does not increase energy security. Considerably more energy, much of it high- grade fossil fuels, is required to produce ethanol than is available in the energy output. About 72% more energy is used to ‘produce a gallon of ethanol than the energy in a gallon of ethanol. Ethanol production from corn is not renewable energy. Its production uses more non- renewable fossil energy resources in growing the corn and in the fermentation/distillation process than is produced as ethanol energy. Ethanol produced from corn and other food crops is also an unreliable and therefore a non-secure source of energy, because of the likelihood of uncontrollable climatic fluctuations, particularly droughts which reduce crop yields. The expected priority for corn and other food crops would be for food and feed. Increasing ethanol production would increase degradation of agricultural land and water and pollute the environment. In U.S. corn production, soil erodes some 18- times faster than soil is reformed, and, where irrigated, corn production mines water faster than recharge of aquifers. Increasing the cost of food and diverting human food resources to the costly and inefficient production of ethanol fuel raise major ethical questions. These occur at a time when more food is needed to meet the basic needs of a rapidly growing world population.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    ISSN: 1573-322X
    Keywords: climate change ; food ; agriculture ; ethics ; technologies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract Burning fossil fuel in the North American continent contributes more to the CO2 global warming problem than in any other continent. The resulting climate changes are expected to alter food production. The overall changes in temperature, moisture, carbon dioxide, insect pests, plant pathogens, and weeds associated with global warming are projected to reduce food production in North America. However, in Africa, the projected slight rise in rainfall is encouraging, especially since Africa already suffers from severe shortages of rainfall. For all regions, a reduction in fossil fuel burning is vital. Adoption of sound ecological resource management, especially soil and water conservation and the prevention of deforestation, is important. Together, these steps will benefit agriculture, the environment, farmers, and society as a whole.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Electronic Resource
    Electronic Resource
    Springer
    Journal of agricultural and environmental ethics 3 (1990), S. 5-20 
    ISSN: 1573-322X
    Keywords: agriculture ; waste ; environment ; economic ; social ; costs ; erosion ; pesticides ; water
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract Because the agriculture/food sectors appear to be driven by short-term economic and political forces, cheap energy, and agricultural-chemical technologies, waste and environmental/social problems in the agricultural/food sectors are estimated to cost the nation at least $150 billion per year. Most of the waste and environmental/social problems can be eliminated through better resource management policies and the adoption of sustainable agricultural practices.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Electronic Resource
    Electronic Resource
    Springer
    Journal of agricultural and environmental ethics 6 (1993), S. 53-60 
    ISSN: 1573-322X
    Keywords: Agriculture ; organic ; energy ; economics ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract The use of organic farming technologies has certain advantages in some situations and for certain crops such as maize; however, with other crops such as vegetables and fruits, yields under organic production may be substantially reduced compared with conventional production. In most cases, the use of organic technologies requires higher labor inputs than conventional technologies. Some major advantages of organic production are the conservation of soil and water resources and the effective recycling of livestock wastes when they are available.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Electronic Resource
    Electronic Resource
    Springer
    Journal of agricultural and environmental ethics 7 (1994), S. 157-172 
    ISSN: 1573-322X
    Keywords: press ; agriculture ; ethics ; newspapers ; farm magazines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Electronic Resource
    Electronic Resource
    Springer
    Journal of agricultural and environmental ethics 5 (1992), S. 1-26 
    ISSN: 1573-322X
    Keywords: sustainability ; environment ; ecology ; development ; resources ; carrying capacity ; eco development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Philosophy
    Notes: Abstract Six separate but related strains of thought have emerged prominently since 1950 in discussions of such phenomena as the interrelationships among rates of population growth, resource use, and pressure on the environment. They are the ecological/carrying capacity root, the resources/environment root, the biosphere root, the critique of technology root, the “no growth”/“slow growth” root, and the ecodevelopment root. Each of these strains of thought was fully developed before the word “sustainable” itself was used. Many of the roots are based on fundamentally opposing assessments of the future of mankind. Many of the roots, such as the ecology/carrying capacity root, are based on physical concepts, and they exclude normative values. Others, such as the ecodevelopment root, include such values as equity, broad participation in governance, and decentralized government. When the word “sustainability” was first used in 1972 in the context of man's future, in a British book,Blueprint for Survival, normative concepts were prominent. This continued to be the case when the word was first used in 1974 in the United States to justify a “no growth” economy. “Sustainability” was first used in a United Nations document in 1978. Normative concepts, encapsulated in the term “ecodevelopment,” were prominent in the United Nations publications. After about 1978, the term “sustainability” began to be used not only in technological articles and reports but also in policy documents culminating in the use of the term in the report of the summit meeting of the Group of Seven in 1989. The roots of the term “sustainability” are so deeply embedded in fundamentally different concepts, each of which has valid claims to validity, that a search for a single definition seems futile. The existence of multiple meaning is tolerable if each analyst describes clearly what he means by sustainability.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    Springer
    Behavior genetics 23 (1993), S. 313-322 
    ISSN: 1573-3297
    Keywords: Homosexuality ; sexual orientation ; familiality ; environment ; genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract We examined data from a large cohort of homosexual and heterosexual females and males concerning their siblings' sexual orientations. As in previous studies, both male and female homosexuality were familial. Homosexual females had an excess of homosexual brothers compared to heteroxual subjects, thus providing evidence that similar familial factors influence both male and female homosexuality. Furthermore, despite the large sample size, homosexual females and males did not differ significantly from each other in their proportions of either homosexual sisters or homosexual brothers. Thus, results were most consistent with the possibility that similar familial factors influence male and female sexual orientation. However, because results conflicted with those of some other studies, and because siblings' sexual orientations were obtained in a manner likely to yield more errors than in these other, smaller studies, further work is needed using large samples and more careful methods before the degree of cofamiliality of male and female homosexuality can be resolved definitively. We also examined whether some parental influences comprised shared environmental effects on sexual orientation. Scales attempting to measure such influences failed to distinguish subjects with homosexual siblings from subjects with only heterosexual siblings and, thus, did not appear to measure shared environmental determinants of sexual orientation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    Springer
    The journal of membrane biology 113 (1990), S. 1-12 
    ISSN: 1432-1424
    Keywords: mercury ; Ca2+ transport ; K+ transport ; sulfhydryl groups ; heavy metals ; rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary The cellular mechanisms by which nephrotoxic heavy metals injure the proximal tubule are incompletely defined. We used extracellular electrodes to measure the early effects of heavy metals and other sulfhydryl reagents on net K+ and Ca2+ transport and respiration (QO2) of proximal tubule suspensions. Hg2+, Cu2+, and Au3+ (10−4 m) each caused a rapid net K+ efflux and a delayed inhibition of QO2. The Hg2+-induced net K+ release represented passive K+ transport and was not inhibited by barium, tetraethylammonium, or furosemide. Both Hg2+ and Ag+ promoted a net Ca2+ uptake that was nearly coincident with the onset of the net K+ efflux. A delayed inhibition of ouabainsensitive QO2 and nystatin-stimulated QO2, indicative of Na+, K+-ATPase inhibition, was observed after 30 sec of exposure to Hg2+. More prolonged treatment (2 min) of the tubules with Hg2+ resulted in a 40% reduction in the CCCP-uncoupled QO2, indicating delayed injury to the mitochondria. The net K+ efflux was mimicked by the sulfhydryl reagents pCMBS and N-ethylmaleimide (10−4 m) and prevented by dithiothreitol (DTT) or reduced glutathione (GSH) (10−4 m). In addition, both DTT and GSH immediately reversed the Ag+-induced net Ca2+ uptake. Thus, sulfhydryl-reactive heavy metals cause rapid, dramatic changes in the membrane ionic permeability of the proximal tubule before disrupting Na+, K+-ATPase activity or mitochondrial function. These alterations appear to be the result of an interaction of the metal ions with sulfhydryl groups of cell membrane proteins responsible for the modulation of cation permeability.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Springer
    Potato research 35 (1992), S. 17-24 
    ISSN: 1871-4528
    Keywords: Solanum tuberosum L. ; soluble solids ; drought ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Potato plants (Solanum tuberosum L.) of the cultivars Alpha, Cara, Blanka, Désirée and Idit, were exposed to a transient water deficit during tuber growth. Drought stress increased the concentration of solutes as assessed by refractometry and lowered the osmotic potentials as assessed by cryoscopy in both leaf and tuber tissues of the five cultivars. Differences among cultivars, as well as between leaf and tuber tissue of the same cultivar, could indicate variability of the soluble components contributing to the osmotic potential. Differences were noted in the response of the cultivars to the environment in terms of osmotic potentials. Essentially, two types of responses were identified: transient maintenance of lower osmotic potential for 24–48 h after stress relief; and inherently high concentration of solutes and low osmotic potential. The possible advantage of sensitivity to environmental changes is also considered.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    ISSN: 1573-5125
    Keywords: heavy metals ; biomonitoring ; bioavailability ; Enteromorpha intestinalis ; Weser estuary
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The present study was planned to assess the validity ofEnteromorpha intestinalis for an active biomonitoring of heavy metals in the Weser estuary. Exposure of cultured algae (active biomonitoring) was carried out in 1987 and 1988, simultaneouslyEnteromorpha spp. was collected from the banks (passive monitoring) in the estuary. Cd, Pb, Ni, Zn and Cu contents of exposed algae were higher than the metal content of collected algae. Metal contents of both collected and field algae varied significantly over space and time. Bioconcentration factors and results of linear regression analysis indicate, that the bioavailability of Cu and Ni varies with regard to the sampling location but cannot be calculated from heavy metal concentration in the water. Due to the different metal and species specific bioavailability, we want to stress the need to monitor contamination of organisms directly. An active biomonitoring usingE. intestinalis will establish a rationale to compare contamination of different estuaries.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Electronic Resource
    Electronic Resource
    Springer
    Journal of applied phycology 5 (1993), S. 425-435 
    ISSN: 1573-5176
    Keywords: Spirulina ; algae ; nutrition ; heavy metals ; fatty acids ; sugars ; amino acids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract ThreeSpirulina and five eukaryotic algal food products available in the Spanish market have been extensively studied. Results are given for their gross chemical composition (water content, crude protein, total carbohydrates, lipids, nucleic acids etc.) and contents of macrominerals, trace elements, fatty acids, amino acids and neutral sugars. The results are compared to those from other studies on natural or laboratory-produced populations. An overall nutritional and toxicological evaluation of these products is included.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Electronic Resource
    Electronic Resource
    Springer
    Computational economics 3 (1990), S. 81-105 
    ISSN: 1572-9974
    Keywords: Decision support ; environment ; knowledge system ; problem processor ; user interface
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Economics
    Notes: Abstract This paper introduces the idea of an environment theory to guide and stimulate research in the DSS field. The proposed line of work builds on and synthesizes findings from a fairly diverse body of related work. Here, we identify fundamental propositions that can serve as a guiding framework for further development of the environment theory.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    ISSN: 1573-5125
    Keywords: heavy metals ; origin and fate ; residues in organisms ; IJsselmeer area
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This review on metal pollution in the Dutch IJsselmeer area is importantly based on Dutch, ‘grey’ literature, including studies set going by governmental authorities and meant to steer policy strategies. It deals with supply, distribution and budgets of dissolved, particulate and sedimentbound heavy metals, preceded by a general description of the area, data on the River Rhine as significant source of water and contaminants, as well as by the enumeration of the many functions of the area, since they perfectly illustrate the urgency for protection of fresh water and of the tuning of the interests in an industrialized, overpopulated country, such as The Netherlands are. The metal concentrations measured in phytoplankton, zooplankton, benthos, fish and birds are presented in relation to the IJsselmeer food web. Effects on organisms have hardly been studied so far. The review is summarized in 21 conclusions. Future ecotoxicological research must be better coordinated and emphasize the effects on the level of the community.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Electronic Resource
    Electronic Resource
    Springer
    Aquatic ecology 26 (1992), S. 577-579 
    ISSN: 1573-5125
    Keywords: Chironomidae ; terrestrial larvae ; agricultural soil ; sewage sludge ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Adult Chironomidae were caught in emergence traps for three subsequent years (1988–1990) on agricultural soil. Larvae were extracted from soil samples taken since June 1989. The field was subdivided into 5 plots treated with different amounts of sewage sludge. On some plots the sludge was artificially enriched with heavy metalts. The phenology of Chrinonomidae in the three years and their distribution over the different plots are discussed. The results suggest that the abundance of Chironomidae is increased by sewage sludge and appears to be also increased by heavy metals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Electronic Resource
    Electronic Resource
    Springer
    Journal of applied phycology 6 (1994), S. 301-308 
    ISSN: 1573-5176
    Keywords: eutrophication ; immobilization ; Selenastrum capricornutum ; running water ; agriculture ; microcosms ; biotesting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cells of the green algaSelenastrum capricornutum were immobilized in alginate beads. The alga was able to grow inside these beads without being grazed by zooplankton. For P-limited immobilized cells, however, a lower µ m and initial slope of the Monod growth curve µ m /K s were found than for free cells. To study the feasibility of immobilized algae to estimate algal growth potentialin situ in aquatic ecosystems, a series of experiments were conducted in indoor model ecosystems (microcosms) and in a small stream. The use of immobilized algae allowed a continuous registration of algal growth potential integrated over periods with natural fluctuations in the environment. The method of encapsulation of the algae can, however, still be improved. The alginate matrix is exposed to marked degradation by microorganisms when incubated in polluted streams for a period longer than two weeks. The applicability of other types of matrices should be tested.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Electronic Resource
    Electronic Resource
    Springer
    Bulletin of experimental biology and medicine 109 (1990), S. 724-727 
    ISSN: 1573-8221
    Keywords: imprinting ; environment ; proliferation ; hepatectomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Electronic Resource
    Electronic Resource
    Springer
    Applied intelligence 3 (1993), S. 317-341 
    ISSN: 1573-7497
    Keywords: Knowledge-based system ; remote sensing ; environment ; image processing ; geographic information system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract This article describes the design and implementation of RESEDA (RemoteSensorDataAnalysis), a knowledge-based system for the extraction of environmental information from digital raster images of the earth. The images may have been obtained from airborne or spaceborne sensors. Ancillary data is used to improve the results of the image analysis; in particular, we are using digital map data stored in a geographic information system for this purpose. The main goal of the system is to provide easy access to remote sensing technology for non-expert users, such as decision makers in environmental management.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    ISSN: 1573-8787
    Keywords: CASE ; environment ; framework ; integration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract In order to investigate the capabilities of varous types of integration infrastructure, the CASE Environments project at the Software Engineering Institute has conducted a series of studies integrating a variety of tools using “framework” technologies. This paper discusses one of these studies, in which a Software Engineering Environment was first modeled using a number of process notations and then constructed using control- and data-oriented frameworks. Public domain, commercial, and custom tools were integrated in support of the defined process scenario.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    Springer
    Water resources management 5 (1991), S. 121-147 
    ISSN: 1573-1650
    Keywords: Irrigation ; agriculture ; soil moisture ; salinity ; crop yield models ; mathematical modelling ; water use in agriculture ; simulation model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract This paper is concerned with the simulation of the water allocation and salt movement in the root zone of a particular crop. A mathematical model of four ordinary differential equations is developed. The model performs water balance and salt balance in unsaturated and saturated regions of the root zone. It is a lumped input and lumped parameter conceptual model, which considers the average soil moisture and salt concentration in the root zone. The equations are solved numerically over the time period of the growing season. Precipitation and irrigation water are treated as inputs. The analyzed results indicate that, for the shallow water table case, the water table elevation has an important effect on the soil moisture depletion dynamics of the unsaturated zone. An appreciable amount of water from the saturated zone is transferred through capillary rise to the unsaturated zone particularly in the case of sandy loam soils. It was found that the water table elevation varies significantly during the growing season. The salt movement simulation indicates a salt concentration build up in the unsaturated zone during the growing season. Contours of equal crop yield reduction as a function of the unsaturated zone initial salt concentration and the irrigation water salt concentration are obtained. The model was tested with data from the Mashtul Pilot Area in Egypt and its performance was satisfactory.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 127 (1990), S. 91-95 
    ISSN: 1573-5036
    Keywords: ash ; compost ; dry matter ; heavy metals ; lindane standards ; persistent pollutants ; ieference base ; soil protection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Concentrations of pollutants in biotic materials are usually related to dry matter. This work demonstrates with the use of heavy metal-contaminated poplar leaves (Populus nigra ‘Italica’), that ash of dry matter (dry ash) obviously yields a better reference, as it eliminates the natural variations among organic substance contents. Values of heavy-metal concentrations in dry ash of leaves were generally more homogeneous and better correlated with corresponding values in air and soil than those in dry matter. It is further shown that concentrations of non-biodecomposable and non-volatile pollutants in the mineral fraction (the same as ash) of, for instance, plants and their residues (autumn leaves, mulch compost) can directly be compared with those in soil (nearly 100% mineral), and vice versa. This facilitates the setting of maximally permissible values for pollutant concentrations in plant dry matter or their residues, and in soil, which can be used in the protection of soils against pollutants accumulated in fresh or fallen leaves, mulch or compost. In this connection, the heavy-metal and lindane margins in West German regulations for issuing environmental certificates for compost products are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    ISSN: 1573-5036
    Keywords: forest floor ; heavy metals ; humic substances ; liming ; sandy soil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The study was carried out in a 40-yr old pine plantation on a Cambic Arenosol within the urban area of Berlin. Lime application (6.1 t ha-1) has led to a pH increase in the forest floor from 3.3 to 5.5 within one year and to a strong stimulation of macrofaunal and microbiological activity. Three years after liming, the C:N ratio of the forest floor decreased from 28 to 25 and P, Pb, Zn, Cu and Cd concentrations in organic matter increased significantly. The organic C pool of the forest floor was almost 7 t ha-1 lower in the limed plot which is attributed to increased microbial respiration. In the mineral soil too, C-pools are lower in the limed plot, amounting to 13.2 t ha-1 or 14% less than in the control. C:N ratios have narrowed significantly from 27–29 to 23 in 10–30 cm depth. The humic acid fraction is lower throughout the limed profile while the percentage of fulvic acids has increased significantly below 10 cm. The results point to severe losses of organic matter and to profound changes in its composition. This may be of consequences for site quality and leaching processes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 125 (1990), S. 119-128 
    ISSN: 1573-5036
    Keywords: ammonia ; application method ; application rate ; environment ; grassland ; nitrogen ; slurry ; volatilization ; wind speed
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Three experiments were conducted to examine the influence of slurry application rate, wind speed and applying slurry in narrow bands on ammonia (NH3) volatilization from cattle slurry surface-applied to grassland. The experiments were conducted in the field using a system of small wind tunnels to measure NH3 loss. There was an inverse relationship between slurry application rate and the proportion of NH4 +-N volatilized. From slurry applied at 20, 40, 60, 80, 100 and 120 m3 ha-1, the respective proportions of NH4 +-N lost by NH3 volatization in 6 days were 60, 56, 49, 40, 44 and 44%. The negative relationship was most pronounced in the first 24 hours after application when 57–77% of the total loss for 6 days occurred. Wind speed had a positive effect on NH3 volatilization, although the effect was small in relation to the total loss; increasing the wind speed from 0.5 to 3.0 m s-1 increased the total 5 day loss by a factor of 0.29. The effect of wind speed was also most pronounced in the first 24 hours when much of the NH3 loss took place. The effect of reducing the surface area of the applied slurry was examined by comparing NH3 volatilization from slurry broadcast across plots with that applied in narrow bands. Although the rate of NH3 volatilization was considerably smaller from the banded application immediately after the slurry was applied, the difference between the treatments progressively narrowed until 2 days after application, after which a higher rate was maintained from the banded slurry. After 5 days the total loss from the banded application was 83% of that from broadcast slurry.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 125 (1990), S. 109-117 
    ISSN: 1573-5036
    Keywords: ammonia ; environment ; grassland ; mechanical separation ; nitrogen ; slurry ; volatilization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Three experiments were conducted using a system of small wind tunnels to measure ammonia (NH3) volatilization from cattle slurry after surface application to land. In each experiment slurry was applied at a rate equivalent to 80 m3 ha-1, providing the equivalent of approximately 100 kg NH4 +-N ha-1. The first experiment compared NH3 volatilization from the liquid fraction obtained by mechanical separation of slurry with that from unseparated slurry. The total NH3 loss over six days from unseparated and separated slurry were very similar, being 38 and 35% respectively of the NH4 +-N applied. For the first five hours, the rate of NH3 loss was higher from the unseparated slurry, thereafter it was consistently lower. In the second experiment, slurry was ponded in a tray to examine whether impeded infiltration or changes in the NH4 + concentration or overall pH of the slurry influenced the rapid decline in rate soon after application that is characteristic of NH3 volatilization from animal slurries applied to land. It appeared, however, that other factors such as resistance to diffusion within the slurry and/or at the slurry surface were mostly responsible for the rapid decline in rate. In the third experiment, in which NH3 volatilization was measured from slurry applied to grassland or bare soil, the total loss from slurry applied to grassland was approximately 1.5 times that from slurry applied to bare soil.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    ISSN: 1573-5036
    Keywords: heavy metals ; hyperaccumulator plant ; pH ; redox potential ; rhizosphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Changes in pH and redox potential were studied in the rhizosphere soil of a nickel hyperaccumulator plant (Alyssum murale) and of a crop plant, radish (Raphanus sativus). Differences in rhizosphere pH and reducing activity were found between the lateral and the main roots of both species, but the pH changes in the rhizosphere were similar in both species. Changes in pH were associated with the relative uptakes of cations and anions; whether the concentrations of heavy metals in the growth medium did not have any effect on the rhizosphere pH. The source of nitrogen (ammonium or nitrate) was the major factor determining the pH of the rhizosphere of both species. The redox potential of the rhizosphere was influenced by both the N-source and the concentrations of heavy metals. When heavy metals were not present in the growth medium, and nitrate was the N-source, the reducing capacity of A. murale roots was enhanced. However, the reducing activity of A. murale was always smaller than that of radish. Therefore, the mechanism of metal solubilization by the hyperaccumulator plant does not involve either the reduction of pH in the rhizosphere or the release of reductants from roots. The acidification and reducing activity of the roots of A. murale was always smaller than that of R. sativus.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 157 (1993), S. 247-256 
    ISSN: 1573-5036
    Keywords: cadmium ; ecotypes ; AM fungi ; Glomus mosseae ; heavy metals ; soil pollution ; spore germination ; tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Spores of arbuscular mycorrhizal (AM) fungi were isolated from two heavy-metal polluted soils in France via trap culture with leek (Allium porrum L.). Preliminary identification showed that the predominant spore type of both cultures (P2 and Cd40) belongs to the Glomus mosseae group. Their sensitivity to cadmium was compared to a laboratory reference strain (G. mosseae) by in vitro germination tests with cadmium nitrate solutions at a range of concentrations (0 to 100 mg L−1) as well as extracts from a metal-polluted and unpolluted soils. Both cultures of AM fungi from heavy-metal polluted soils were more tolerant to cadmium than the G. mosseae reference strain. The graphically estimated EC50 was 0.8 mg L−1 Cd (concentration added to the test device) for G. mosseae and 7 mg L−1 for P2 culture, corresponding to effective Cd concentrations of approximately 50–70 μg L−1 and 200–500 μg L−1, respectively. The extract of the metal-polluted soil P2 decreased germination of spores from the reference G. mosseae but not from P2 culture. However, the extracts of two unpolluted soils with different physico-chemical characteristics did not affect G. mosseae, whereas germination of P2 spores was markedly decreased in the presence of one of the extracts. These results indicate a potential adaptation of AM fungi to elevated metal concentrations in soil. The tested spores may be considered as metal-tolerant ecotypes. Spore germination results in presence of soil extracts show the difficulty of assessing the ecotoxic effect of metals on AM fungi without considering other soil factors that may interfere in spore germination and hyphal extension.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    ISSN: 1573-5036
    Keywords: aggressive strains ; composted pine bark ; environment ; in vitro ; Rhizoctonia ; soil ; sources ; seedling nursery ; Trichoderma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Trichoderma isolates were collected from different sources and screened for their in vitro parasitism of Rhizoctonia solani. They were grouped according to the different sources and each group compared statistically. 74% of the total isolates collected were regarded as antagonistic to R. solani in vitro. Isolates associated with pine bark source were very aggressive. The most aggressive strains were isolated from soil samples collected under the Speedling® trays of a commercial seedling nursery.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 159 (1994), S. 27-35 
    ISSN: 1573-5036
    Keywords: agriculture ; arbuscular-mycorrhizas ; economic analysis ; management
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The benefits of management of mycorrhizas in agricultural and horticultural croppiing systems remains problematic except where the indigenous fungal population is low. Most experiments have focused on the introduction of exotic fungal isolates. Promotion of plant growth by mycorrhizas can be enhanced by increasing the effectiveness of the indigenous fungi as well as by introducing more effective species. Lack of reliable methods for identification of fungal species colonizing roots is a major limitation to characterizing the change in mycorrhizal populations. Assessment of the role of mycorrhizas in commerical food production systems must include an economic analysis. To do so requires an evaluation of the response to increasing the effectiveness of the mycorrhizal symbiosis relative to increasing yield with addition of phosphorus fertilizer. Thus field experiments should be designed to measure the response to phosphorus addition with the existing mycorrhizal population as well as with the more effectively managed population. In this paper we discuss changes that may be induced in mycorrhizal fungi by management to increase their effectiveness in promoting plant growth. We then suggest an economic analysis approach to assessing the potential benefits of this increase in effectiveness. We conclude with a discussion of research approaches needed to determine, in a more objective manner, the role of mycorrhizas in managed ecosystems.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    ISSN: 1573-5036
    Keywords: AM fungi ; Glomus ; heavy metals ; spore germination ; tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Spores of arbuscular mycorrhizal fungi were isolated from two soils of field trials at INRA-Bordeaux (France) polluted by long-term application of a zinc-polluted sewage sludge (S2 soil) or treated with cadmium nitrate (Cd40 soil) and from corresponding unpolluted soils (F and Cd0 soils). These AM fungi were tested for their tolerance to Cd and Zn added as salt solutions with increasing concentrations (0 to 10 mg L−1) in a simple spore germination device. According to preliminary identification the predominant species in S2 and F cultures was Glomus mosseae, whereas Cd40 and Cd0 cultures contained a mixture of at least G. mosseae and G. etunicatum. Germination of Cd40 spores was more tolerant to Cd and Zn than for Cd0 spores, with EC50 values of 73 and 158 μmol L−1 added Cd and Zn corresponding to approximately 10 and 13 μmol L−1 remaining in solution in the device. The S2 spores from the sludge contaminated soil were more tolerant to Zn (EC50=87 μmol L−1), but not to Cd (EC50=7.5 μmol L−1), than the spores from the farmyard manure-treated F soil (EC50=38 and 8.8 μmol L−1, respectively). Thus, S2 culture exhibited a specific tolerance to Zn, which was lower than the unspecific tolerance of Cd40 culture to both Cd and Zn, despite the much higher Zn availability in S2 soil. These results indicate that AM fungi from different soils may differ in their metal susceptibility and that both metal specific and unspecific tolerance mechanisms may be selected in metal polluted soils.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    ISSN: 1573-5079
    Keywords: heavy metals ; enzymes ; photosynthetic carbon reduction cycle ; pigeonpea ; leaves
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of Cd2+ and Ni2+ on the rate of photosynthesis and activities of key enzymes of the photosynthetic carbon reduction cycle was examined in leaves from pigeonpea (Cajanus cajan L., cv. UPAS-120) grown in nitrogen free sand culture. Two different concentrations of Cd2+ and Ni2+ were applied through the rooting medium at two growth stages. The application of Cd2+ and Ni2+ (0.5 and 1.0 mM) at an early vegetative stage (30 days after sowing) resulted in about 50% and 32% reduction in net photosynthesis, respectively. However, enzyme activities were decreased to different levels (2–61%) depending upon the enzyme and the concentration of the metal ion. These concentrations (0.5 and 1.0 mM of Cd2+ and Ni2+) had no effect when applied at a later vegetative stage i.e. 70 days after sowing. However, when the concentration of Cd2+ was increased to 10 mM, there was about an 86% reduction in the rate of photosynthesis but the enzyme activities were reduced by only about 40%. Although Ni2+ reduced the photosynthetic rate by 65%, it had little effect on enzyme activities. The reduction in photosynthesis seems to occur indirectly through a decrease in chlorophyll content and stomatal conductance but not due to decreased enzyme activities. Oxygen evolution by leaf discs was inhibited by Cd2+ and Ni2+ in parallel with a reduction in photosynthesis. These data confirm the earlier reported effects of Cd2+ and Ni2+ on O2 evolution in isolated chloroplasts.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    ISSN: 1573-5036
    Keywords: arsenic ; boron ; chronium ; copper ; heavy metals ; N-fixation ; plant availability/growth/uptake ; roots ; sawdust ; soil pH ; tops ; yield
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A pot trial was conducted to determine the effects, on plant growth and element uptake, of soil amendment with Cu- Cr- and As-(CCA) treated, or boric-treated sawdust. Three indicator plants (beetroot, white clover, lettuce) were chosen and the trial was carried out at both soil pH 5 and pH 7. Comparisons were made with an untreated sawdust amendment and with a non-sawdust control. Amendment with 10% treated-sawdust (v/v) increased soil concentrations of Cu, Cr, As and B, by 45, 136, 63 and 32 mg kg-1, respectively. Much of the Cu and B was extractable using standard soil extractants, but extract concentrations of Cr and As were below detection limits. Seeds germinated in all pots, but the boric treatment subsequently proved unsatisfactory as a growth medium for all plants except beetroot grown at pH 7. The CCA treatment had no negative effect on any of the plants at either pH, but yield depression occurred with untreated sawdust. This was attributed to nutrient immobilization by the decomposing untreated sawdust. Plant roots, especially beetroot fibrous roots, in the CCA treatment, concentrated Cu, Cr and As to high levels. Uptake of these elements was generally higher at pH 5 than at pH 7. However, the above-ground parts of the plants, and the beetroot bulbs, i.e. the normal edible parts, had very much lower concentrations. Although Cu was concentrated to some extent in beetroot and clover, the concentrations were below animal toxicity levels, especially at the higher soil pH. B, in contrast, was concentrated in the above-ground portions of the plants, in preference to the roots. These treatments had no important effects on the uptake of major and minor nutrient elements by the plants. Clover nitrogen-fixation was not adversely affected by the CCA treatment, but was totally absent in the boric treatment. These rerults are discussed, and the need to conduct tests on a wider range of edible plants before concluding that amendment with CCA-treated sawdust may be acceptable, is stressed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 141 (1992), S. 1-11 
    ISSN: 1573-5036
    Keywords: chemical fertilizer ; crop production ; developing countries ; environment ; inoculation ; legume ; pollution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The economic and environmental costs of the heavy use of chemical N fertilizers in agriculture are a global concern. Sustainability considerations mandate that alternatives to N fertilizers must be urgently sought. Biological nitrogen fixation (BNF), a microbiological process which converts atmospheric nitrogen into a plant-usable form, offers this alternative. Nitrogen-fixing systems offer an economically attractive and ecologically sound means of reducing external inputs and improving internal resources. Symbiotic systems such as that of legumes and Rhizobium can be a major source of N in most cropping systems and that of Azolla and Anabaena can be of particular value to flooded rice crop. Nitrogen fixation by associative and free-living microorganisms can also be important. However, scientific and socio-cultural constraints limit the utilization of BNF systems in agriculture. While several environmental factors that affect BNF have been studied, uncertainties still remain on how organisms respond to a given situation. In the case of legumes, ecological models that predict the likelihood and the magnitude of response to rhizobial inoculation are now becoming available. Molecular biology has made it possible to introduce choice attributes into nitrogen-fixing organisms but limited knowledge on how they interact with the environment makes it difficult to tailor organisms to order. The difficulty in detecting introduced organisms in the field is still a major obstacle to assessing the success or failure of inoculation. Production-level problems and socio-cultural factors also limit the integration of BNF systems into actual farming situations. Maximum benefit can be realized only through analysis and resolution of major constraints to BNF performance in the field and adoption and use of the technology by farmers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Springer
    Plant and soil 154 (1993), S. 1-5 
    ISSN: 1573-5036
    Keywords: heavy metals ; lead ; Lupinus albus L. ; stripping voltammetry ; white lupin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract An anodic stripping voltammetry method for the simultaneous determination of trace heavy metals in nutrient solutions, soils and plants has been developed at a hydrodynamic electrochemical sensor. Several parameters were optimized in order to enhance sensitivity. Calibration curves in different media are presented. The study of the uptake of lead by white lupin (Lupinus albus L.) was carried out. Toxicity symptoms were observed and compared with levels of lead measured in roots and leaves.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    ISSN: 1573-5036
    Keywords: citrate ; copper transport ; heavy metals ; nicotianamine ; tomoto ; xylem exudate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The influence of Fe nutrition on the distribution of the heavy metals Fe, Mn, Zn, and Cu and of the heavy metal chelators nicotianamine (NA) and citrate in 6 different shoot and 3 different root parts and in xylem exudate of a NA-containing tomato wild type and its NA-less mutant was investigated. Under the same Fe supply the mutant showed higher Fe, Mn, and Zn concentrations in all organs investigated, with exception of the shoot apex. The Cu concentration in the mutant was only in root parts higher than in the wild type but much lower in leaves. Analyses of xylem exudate showed that Fe, Mn, and Zn were readily translocated by both genotypes from the roots to the shoot at all levels of Fe supply, whereas in the absence of NA, Cu was only poorly transported. Citrate as main Fe chelator in the xylem was present in high concentrations in xylem exudate of the wild type under low Fe supply but in the mutant also at 10 μM FeEDTA. NA occurred in xylem exudate of the wild type in concentrations high enough to chelate heavy metal ions. Generally, high Fe supply induced a decrease of Mn, Cu, and Zn concentrations in all organs of the wild type whereas high concentrations were observed in most cases under Fe deficiency. A positive correlation between Fe supply and NA concentration existed only in the shoot apex and in the xylem exudate of wild type plants. From the correlation between Cu and NA translocation and from the high stability constant of the NA-Cu-complex (log K=18.6) it is concluded that NA is a chelator for Cu in the xylem, whereas the translocation of Fe, Mn, and Zn is independent of NA.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    ISSN: 1573-5036
    Keywords: Alyssum murale ; heavy metals ; hyperaccumulator plant ; metal tolerance ; pH ; proton release ; Raphanus sativus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The proton release by a species that can hyperaccumulate nickel (Alyssum murale) and by a non-accumulator (Raphanus sativus L.) was studied at different pH and heavy metal concentrations in solution culture. Both factors influenced the growth and composition of the plants.A. murale was more sensitive than radish to a decrease of pH from 7.0 to 6.0 in the growth medium; plant yield and proton production diminished with decreasing pH. However, yields and proton production of radish only decreased at pH 5.5. The differences in the amounts of protons produced between the hyperaccumulator species and radish were not large enough to conclude that decreasing pH in the rhizosphere ofA. murale is a mechanism for heavy metal solubilization. Nickel concentrations inA. murale followed the typical pattern of an accumulator plant — more Ni was accumulated in the shoots than in the roots. Lower concentrations of Zn and Cd occurred in the shoots than in roots ofA. murale, and also of Ni in radish. The concentrations of Co inA. murale shoots were increased when Zn, Ni and Cd were absent from the nutrient solution. However, Co concentrations in radish shoots were independent of the concentrations of other heavy metals in the growth medium.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    ISSN: 1573-5036
    Keywords: heavy metals ; mining dump ; Minuartia verna ; Silene vulgaris
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Plant and soil samples from a mining area in Carinthia (Austria) were investigated for their heavy metal content. In the soil surrounding roots of plants (Minuartia verna and Silene vulgaris) growing on the mining dumps, high concentrations of lead and zinc are to be expected. The two species (Minuartia and Silene) show very different heavy metal concentrations in their above- and belowground organs. From these observations it can be concluded that the divergent distribution of heavy metals within the plants is an important mechanism of tolerance to heavy metals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    ISSN: 1573-5117
    Keywords: freshwater ecosystem ; Bryozoa ; Phylactolaemata ; biomass ; heavy metals ; PCB
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the Meuse River (Liège area, Belgium), large amounts of three species of Bryozoans, Fredericella sultana (BLUM.), Plumatella emarginata ALL. and Plumatella fungosa (PALL.) occur. They cover 3 to 40% of the bank walls and their biomass ranges from 12 to 293 g m−2 (dry weight). In the heated waters of a nuclear power plant (Tihange) and of industries lined up along the river, colony development occurs 3 to 4 weeks earlier than at an upstream station. The heavy metal content of living colonies ranges from 4 to 21 mg kg−1 Cd, 45 to 182 mg kg−1 Cu, 803 to 2232 mg kg−1 Zn, 150 to 483 mg kg−1 Pb and 21 to 138 mg kg−1 Cr (DW). The mean concentration of PCBs was 925 µg kg−1 (DW). Heavy metal and PCB concentrations in the sediments were close to those of colonies, suggesting that most of the pollutants found in the Bryozoans is in fact in the sediment trapped by the colonies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    ISSN: 1573-5117
    Keywords: grain size correction ; organic micropollutants ; heavy metals ; sediments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four grain size correction procedures were tested for their applicability for comparing concentrations of heavy metals and organic micropollutants (PCBs, PAHs) in sediments. A simple and straightforward procedure proved best: wet sieving of fresh sediment, isolating and analysing the 〈 63 μm grain size fraction and expressing the pollutant concentration as a proportion of the fraction's dry weight. The total analytical errors, expressed as the variation coefficient of the average concentrations, were 3.8–7.6% for heavy metals, 12–24% for PCBs and 5.3–9.9% for PAHs.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 649-660 
    ISSN: 1573-5117
    Keywords: in-place pollutants ; heavy metals ; sorption ; adsorption ; desorption ; sediments ; contaminants ; resuspension ; partitioning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediment resuspension plays a dominant physical role in downstream transport of sediment-bound, or ‘in-place’ pollutants. During resuspension, however, numerous sorption reactions may alter contaminant phase distributions. Previous field resuspension studies on heavily contaminated sediments (Theis et al., 1988, J. Great Lakes Res. 14, 216) showed parallel trends in metal partitioning with pH and time for each of 7 metals (Cd, Co, Cr, Cu, Ni, Pb, Zn), when pH was 〈 7.5 during resuspension. To improve our ability to interpret follow-up laboratory partitioning experiments using sediments from the field sites, we conducted an evaluation of sediment sample storage as a potential factor leading to field-laboratory partitioning differences. Although metal sorption observed in the laboratory differed substantially from that observed in the field, sample storage effects, reported as holding time and changes in solid phase metal fractionation, gave minimal support for the hypothesis that sample storage caused the differences. It appears, rather, than our in vitro batch equilibrium systems incompletely replicated those attributes of a sediment-water system that are relevant to adsorption and desorption of heavy metals during a resuspension event. Accordingly, we conclude that a general improvement in the understanding of contaminant partitioning would result if future studies would assign greater importance to evaluating the effects of relevant physical phenomena on partitioning (e.g. particle interaction and shear stress), in addition to such widely studied chemical determinants as pH, time, and metal species.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    ISSN: 1573-5117
    Keywords: organic micropollutants ; heavy metals ; water quality ; sediment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Linggi River drainage basin in Negeri Sembilan Malaysia is the major source of potable water for the townships of Seremban and Port Dickson. Water quality is threatened by industrial and commercial development taking place in the basin. This study investigated the concentrations and distribution of organic micro-pollutants and heavy metals within the catchment. Arsenic, copper, cadmium, lead, mercury and zinc were determined in water and sediment samples. All heavy metal concentrations were increased down the basin; arsenic and copper concentration in particular were elevated probably due respectively to flow in of arsenical herbicides in rubber and oil palm plantations and copper sulphate and an additive in pig food. Total phenol concentration also increased considerably within the catchment as a result of urbanisation. Five priority phenolic pollutants (2,4-dimethylphenol; 4-chloro-3-methylphenol; 2,4,6-trichlorophenol; 4-introphenol; pentachlorophenol) were found.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 723-730 
    ISSN: 1573-5117
    Keywords: sediment ; heavy metals ; environmental control ; industrial emissions ; sequential leaching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A number of investigations of river pollution in Austria are reported. Analysis of wastewater and river water was supplemented by investigations of sediments to characterize the influence of the different emission sources on the aquatic ecosystems. Examples of sediment investigations as tools for environmental monitoring are presented and the advantages of these methods are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    ISSN: 1573-5117
    Keywords: heavy metals ; sediment ; zooplankton ; epibenthic invertebrates ; Banc d'Arguin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The concentrations of copper, zinc, lead and cadmium in the surface sediment (upper 5 mm) were generally higher in the silt fraction than in the bulk sediment. No significant geographical trend in the metal concentrations of the surface sediments was found, nor a correlation between concentrations in bulk sediment as well as in the silt fraction and the % silt could be established. In general, the metal concentrations in both bulk sediment and silt are lower, when compared to marine environments in other climatological regions. In zooplankton, the metal concentrations were relatively high: expressed in µg g−1 on a dry weight (D.W.) basis, they ranged from 15–90 for copper, 70–580 for zinc, 12–55 for lead and 4–10 for cadmium. In epibenthic invertebrate species, both in crustaceans and bivalve molluscs, the concentrations of copper, zinc, and lead were in the same order of magnitude as compared to corresponding species from other geographical latitudes. Cadmium concentrations were relatively low, ranging from 0.13–0.42 µg g−1 D.W. in the bivalve molluscs Pitaria tumens and from 0.04–0.27 µg g−1 D.W. in the shrimp Processa elegantula. Also in the crab species Ilia spinosa, Inachus sp. and Pagurus sp., the cadmium concentrations were low, varying between 0.1 and 0.2 µg g−1 D.W. No significant relation between the metal concentration in whole-body samples and sediment (either bulk or silt) was present. Also no gradient was apparent in concentrations in organisms sampled at different depths (5 to 200 m) along two off-shore transects perpendicular to the Banc d'Arguin. Data indicated lower metal concentration in epibenthic organisms from sampling stations along a northern transect (southwest of Cap Blanc) than in organisms from the southern transect, off Cap Timiris. Evidence was obtained for a considerable atmospheric input of heavy metals, in particular zinc and lead, in a certain area along the continental slope of the Banc d'Arguin.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 275-276 (1994), S. 359-369 
    ISSN: 1573-5117
    Keywords: agriculture ; blue-green algae ; eutrophication ; internal loading ; nitrogen ; phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The impact of agriculture was estimated on two shallow, eutrophic lakes, Lake Kotojärvi and Lake Villikkalanjärvi in southern Finland. The main emphasis was on phosphorus and nitrogen budgets and on the phytoplankton dynamics. Special attention was paid to internal P loading and blue-green algal blooms. The mean Tot-P load from agricultural land was 1.2 kg ha-1 a-1 in both basins and Tot-N loads were 19 kg ha-1 a-1 in L. Villikkalanjärvi and 12 kg ha-1 a-1 in L. Kotojärvi. The Tot-P input to L. Kotojärvi was on an average 0.62 g m-2 a-1 (per lake surface area), and the Tot-N input 9.1 g m-2 a-1. The corresponding inputs to L. Villikkalanjärvi were 3.1 and 57 g m-2 a-1, respectively. The annual variation followed the runoff volumes. About half of the Tot-P and one third of the Tot-N load was retained in L. Kotojärvi. In L. Villikkalanjärvi the retention was only 24% for Tot-P and 19% for Tot-N. The difference was very probably due to a longer theoretical retention time in L. Kotojärvi. In L. Villikkalanjärvi the mean concentration of Tot-P was 120 µg 1-1 and that of Tot-N 1700 µg 1-1 and the corresponding figures in L. Kotojärvi 67 and 990 µg 1-1, respectively. The mean chlorophyll a concentration was, however, higher in L. Kotojärvi (26 µg 1-1) than in L. Villikkalanjärvi (20 µg 1-1). This was probably due to an internal P load in L. Kotojärvi: in 1988 the internal load of dissolved P was estimated to be as much as twofold the external load. In L. Villikkalanjärvi the internal dissolved P load was only up to 50% of the external input. In L. Kotojärvi the high internal P load coupled with a low DIN:DIP ratio resulted in a strong blue-green algal bloom in the summer of 1988. In L. Villikkalanjärvi blue-green algae were observed only in small amounts. Even in August 1990, when the DIN:DIP ratio was low enough to favor the occurrence of blue-green algae, they contributed only up to 10–15% of the total phytoplankton biomass.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 285 (1994), S. 139-150 
    ISSN: 1573-5117
    Keywords: marine ; environment ; management ; resources ; development ; protection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The seas of Southeast Asia play an important role in the economy of the surrounding countries. The region's constantly expanding coastal population and development has made great demands on marine resources, with growing evidence seen in the further degradation of the marine environment and continued exploitation of living as well as non-living resources. Integrated coastal area management has never been considered in the past while environmental protection measures and policies have largely been at local or national levels. Implementation of regional study programmes less than 10 years ago and ratification of international as well as regional agreements aimed at protecting the marine environment in recent times indicate a more enlightened approach to the problem.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 97-105 
    ISSN: 1573-5117
    Keywords: heavy metals ; mass balance ; resuspension ; sedimentation ; field study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The contribution of erosion of bed sediment to the load of metals leaving Lake Ketelmeer, a shallow lake in the Netherlands fed by the IJssel branch of the River Rhine, is reported. Transport of suspended matter and associated trace metals was measured using both centrifuges and sediment traps at several locations in the lake. Mass balances of suspended matter and heavy metals were calculated using data from these field measurements. Metal/scandium-ratios were used to identify the source of the suspended matter in the lake. Since the bed sediment is more polluted than the suspended sediment entering the lake, higher metal/scandium-ratios were found for bottom sediment in the lake compared with those for suspended matter entering the lake from the River IJssel. Using the metal/scadium-ratio in suspended matter from the lake, it was calculated that bottom sediments made up 43% of the suspended matter leaving the lake. This implies an erosion flux of bottom sediment of 16 g m−2 d−1. For cadmium, mercury, chromium and zinc, this erosion process accounts for more than 50% of the pollutant load leaving Lake Ketelmeer and entering Lake IJsselmeer.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    ISSN: 1573-5117
    Keywords: benthic chamber ; benthic fluxes ; heavy metals ; pore water
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Concentrations of the heavy metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in sea water, suspended matter, sediments and pore water samples collected in a coastal area of the middle Tyrrhenian Sea. Concentration factors between pore water (extracted from the first centimeter of the sediments) and the overlying sea water (taken 30 cm above the sea bed) were less than 1 for Cr, Cu and Pb, 1–10 for Cd and Ni, 10–100 for Fe and Co, 100–1000 for Mn, and 1–100 for Zn. The benthic fluxes of heavy metals at the sediment-water interface were measured directly using in situ benthic chambers and calculated using Fick's first law during two experimental periods, one in 1986 and the other in 1988. The fluxes of Cu, Ni, Pb and Zn varied significantly over time; this appeared to be related to their relatively low (≤ 10) concentration factors. From the benthic chamber experiments, metals with positive fluxes were in the order: Mn 〉 Fe 〉 Co 〉 Cd, while those with negative fluxes were: Zn 〉 Pb 〉 Ni ≅ Cu. Fluxes calculated using Fick's Law were: positive − Mn 〉 Fe 〉 Zn (or Zn 〉 Fe) 〉 Ni 〉 Co 〉 Cd, negative fluxes Pb 〉 Cu 〉 Cr. Measured (benthic chamber) and calculated (Fick's first law) fluxes for Co, Cd, Mn, Pb and Fe were comparable within an order of magnitude, although less agreement was found for Cu, Ni and Zn. Removal of Ni and Zn at the sediment-water interface has been proposed to explain the fact that the measured and calculated fluxes have opposite directions for these metals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 1573-5117
    Keywords: heavy metals ; bioavailability ; coastal lagoons ; sediments ; macrophytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The distribution and bioavailability of trace metals in two contrasting tropical coastal lagoons were studied. The concentration of trace metals in aquatic macrophytes was compared with those found in sediments under weakly and strongly bound forms. The results showed that total metal concentrations in sediments did not explain the concentration found in plants. The highest concentrations in macrophytes were observed in the lagoon which had a higher fraction of metals weakly bound to sediments, but presented the lower total metal content. Low redox potential was the major variable keeping metals in non-bioavailable forms, possibly as refractory sulfides and metal-organic complexes. Among the macrophytes, rooted species showed lower concentrations of metals as compared to algae.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 287 (1994), S. 179-194 
    ISSN: 1573-5117
    Keywords: agriculture ; phosphorus ; bioavailability ; bioassays ; isotherms ; eutrophication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The potential bioavailability of phosphorus in agriculturally loaded rivers of southern Finland was determined by an algal bioassay and the release of the potentially bioavailable particulate P was estimated by sorption studies. According to the bioassay 0 to 13.2 per cent (mean 5.1%) of the particulate P in river water samples was potentially bioavailable. Dissolved reactive P (DRP) in river waters appeared to be totally bioavailable whereas the dissolved unreactive P appeared not to be utilized by algae. In addition to river waters two lake sediment samples were also assayed. In these samples 0 and 2.6% of the P was bioavailable. The potential bioavailability of particulate P in agriculturally loaded rivers obtained in this study was lower than that reported in studies from other countries. The difference was assumed to arise partly from methodological factors and partly from the nature of the Finnish soils. The EPC (equilibrium phosphate concentration) values indicated that during the period when most of the agricultural loading enters the lakes in Finland, potentially bioavailable P is not released from the particles because of the relatively high DRP concentration in the receiving waters. However, during the algal production period the DRP concentration in lakes decreases below the EPC and potentially bioavailable particulate P is desorbed. The increase in pH during this period may further enhance the desorption of P.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    ISSN: 1573-5117
    Keywords: acidification ; heavy metals ; Chironomus ; diversity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Recently formed beaver-ponds surrounding an abandoned copper-nickel ore roast yard near Sudbury, Ontario, Canada, were influenced by highly acidic and heavy-metal contaminated effluent. Fish, including Culaea inconstans, Phoxinus neogaeus, Phoxinus eos, and Pimephales promelas, were found in the ponds upstream of the roast yard only. Macroinvertebrate taxon richness and diversity were greater in the upstream ponds than in the downstream ponds. Acid intolerant taxa, including Mollusca and Hyalella azteca, were found upstream only; acid tolerant taxa, including Enallagma and Ischnura (Odonata: Coenagrionidae) were found in the downstream ponds. One taxon, a species of Chironomus, was especially tolerant of both acid and metal stresses, and was the only invertebrate taxon found in the pond located directly on the roast yard itself. We conclude that long-abandoned mining and refining sites can continue to have a marked effect on aquatic communities.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    ISSN: 1573-5117
    Keywords: heavy metals ; sediments ; Calcasieu River/Lake ; Louisiana
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The heavy metals Cd, Cr, Cu, Pb, Hg, Ag, and Zn, and the metalloid As were measured in surface sediments at permanent stations located in the Calcasieu River/Lake Complex. The relationships among metal concentrations in different areas of the system were investigated to determine sources, source strength, and transport. The point-source inputs of heavy metals were assumed to be industrial outfalls (Bayou d'Inde) and sewage outfalls (Bayou d'Inde and Contraband Bayou). Although these inputs have not seriously affected the entire river/lake system, stressed regions exist within each bayou. The background levels of arsenic and heavy metals were: 0.60 (As), 0.3 to 1.4 (Cd), 25 (Cr), 10 (Cu), 15 (Pb), 〈 0.05 (Hg), 0.07 (Ag), and 40 mg kg−1 (Zn). Stations near sewage outfalls and industrial outfalls had increased metal concentrations above these background levels, but the increases were restricted to the regions near the outfalls. The metals discharged into the bayous were not being transported to the remainder of the river/lake complex.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 203 (1990), S. 155-164 
    ISSN: 1573-5117
    Keywords: Asellus aquaticus ; Crustacea ; heavy metals ; toxicity ; toxicity test
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of heavy metals on the isopod Asellus aquaticus (L.) are studied by static toxicity tests. Results demonstrate that the species is sensitive to Cd+2, Cr+6, Cu+2, Fe+3, Hg+2, Ni+2 Pb+2 and Zn+2, but the toxicity of each metal is different. Differences are also found between adults and between adults and juveniles. The comparative analysis of all data on the toxicity has been performed on the concentrations of metal ions and not on metal compound concentrations. Criteria for establishing water quality in order to guarantee protection of the environment are discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    ISSN: 1573-5117
    Keywords: palaeolimnology ; integrated monitoring ; heavy metals ; 210Pb ; diatoms ; Cladocera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A palaeolimnological study of Lake Iso-Hietajärvi in Patvinsuo National Park, Lieksa, East Finland was conducted. The drainage area of the lake is one of four Integrated Monitoring areas established in Finland. Lead-210 dating reveals a period of increased sedimentation in the lake from 1920 to 1950. Increased atmospheric burden of several heavy metals in the order Pb 〉 Cu〉 Zn 〉 Ti = Al 〉 Cr = Ni = V is recorded. The first to expand during the 19th century is Pb, whilst V increases after 1950. Sedimentary chlorophyll derivatives expand in the early part of the 20th century. Assemblages of diatoms and Cladocera were also changed somewhat during this time, but water quality seems not to have varied much: e.g. the diatom-inferred pH has remained in the range 6.4–6.8 (with a slight decrease) throughout the period of study.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 219 (1991), S. 269-279 
    ISSN: 1573-5117
    Keywords: water ; sediments ; oil ; heavy metals ; PCBs ; plankton ; clams ; fish ; birds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Despite extensive urbanization of its watershed, the Detroit River still supports diverse fish and wildlife populations. Conflicting uses of the river for waste disposal, water withdrawals, shipping, recreation, and fishing require innovative management. Chemicals added by man to the Detroit River have adversely affected the health and habitats of the river's plants and animals. In 1985, as part of an Upper Great Lakes Connecting Channels Study sponsored by Environment Canada and the U.S. Environmental Protection Agency, researchers exposed healthy bacteria, plankton, benthic macroinvertebrates, fish, and birds to Detroit River sediments and sediment porewater. Negative impacts included genetic mutations in bacteria; death of macroinvertebrates; accumulation of contaminants in insects, clams, fishes, and ducks; and tumor formation in fish. Field surveys showed areas of the river bottom that were otherwise suitable for habitation by a variety of plants and animals were contaminated with chlorinated hydrocarbons and heavy metals and occupied only by pollution-tolerant worms. Destruction of shoreline wetlands and disposal of sewage and toxic substances in the Detroit River have reduced habitat and conflict with basic biological processes, including the sustained production of fish and wildlife. Current regulations do not adequately control pollution loadings. However, remedial actions are being formulated by the U.S. and Canada to restore degraded benthic habitats and eliminate discharges of toxic contaminants into the Detroit River.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 233 (1992), S. 165-170 
    ISSN: 1573-5117
    Keywords: eutrophication ; policy ; environment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Project on the Water Quality Research in the Loosdrecht Lakes (WQL) has come up to the expectations of the Netherlands Environment Ministry. The results reaffirm the main lines of national eutrophication policy drawn up in 1979 (Policy Document on Phosphates) and further developed in the eighties. Interesting new insights have been gained, for example into the role of sediment and seston as well as into the relative importance of trophic levels. It is not possible, however, to definitely establish the effect of WQL on eutrophication policy. The Loosdrecht project is an example of genuine ecological research, incorporating several disciplines, placing the object of research into its surroundings, emphasising the relation nature-culture and committing itself to certain value judgements and policy choices. As a consequence, there is a striking resemblance between the evolution of the project itself and that of ecosystems. All in all the Loosdrecht project should be regarded as a paradigm for future ecosystem studies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 247-255 
    ISSN: 1573-5117
    Keywords: suspended sediment ; flood waves ; sources ; transport processes ; nutrients ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Changes of water and suspended sediment composition during three single flood events were investigated in two small catchments in the Mosel region. In addition to suspended sediment characteristics (turbidity, loss on ignition, density, chlorophyll content), several different nutrients and heavy metals were determined in the dissolved and particulate phase. The flood events investigated were characterized by a single peaked hydrograph. In contrast suspended sediment concentrations and the other parameters showed more complex behaviour. The transport of suspended sediment was not only controlled by discharge magnitude. In the course of a flood event different suspended sediment sources are activated. Using the chemograph and the timing of samples collected during the hydrograph these suspended sediment sources can be identified. In addition to the remobilization of sediment and channel erosion, inputs of suspended solids from a sewage plant, road discharge, topsoil and interflow could be identified.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 597-603 
    ISSN: 1573-5117
    Keywords: Stormwater ; enzyme activity ; heavy metals ; speciation ; sediments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of stormwater and combined sewer overflows on receiving waters were investigated using measurements of bacterial enzyme activity and metal speciation in the sediments of five urban rivers. Free flowing urban rivers had high enzyme activity and low metal concentration in sediments, indicating a lack of contribution by stormwater sediments. More stagnant urban rivers, which tended to trap sewer-discharged sediments, were characterised by inhibited enzyme activity and high ammonium acetate- and EDTA-extractable metal concentrations. Profiles along two urban rivers showed a direct inhibition of enzyme activity at sites of stormwater and industrial discharge. Deposited sewage, from combined sewer overflows, was indicated by highly elevated enzyme activity and metal concentrations. The results of this study demonstrate that the ecologically relevant enzyme activity measurement may be a useful complement to metal speciation analysis when investigating the effects of stormwater discharges on urban rivers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 235-236 (1992), S. 605-610 
    ISSN: 1573-5117
    Keywords: heavy metals ; sediments ; bioavailability ; transfer processes ; mobilization ; salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The transfer of metals from contaminated sediments to algal cell walls (Scenedesmus quadricauda) and organisms from various trophic levels (euryhaline osmoconform hydroid Cordylophora caspia and algae Brachiomonas submarina) was studied with a multichamber device. The system consists of a central chamber which contained the mud suspension and six external chambers containing the different biological indicators. The solids in the central and external chambers are separated by 0.45 μm-diameter membranes which allow diffusion of the mobilized, dissolved metal compounds. Experiments were performed with dredged sediments at various salinities (0.5, 1.0, 1.5, and 2.0 percent, respectively) and the kinetic of re-adsorption was obtained by taking samples after different time intervals. High enrichment of Cd was found in the living alga Brachiomonas submarina, but on the other side only a weak influence of salinity on re-adsorption could be observed. Model experiments with ionic Cd showed a clear dependency on Cd-sorption on the algae, Cd-concentration in solution, and salinity. These results indicate that the transfer of metals mainly depends on the specific surface properties of the substrates and on the specific chemical form of the dissolved mobilized metal.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    ISSN: 1573-5117
    Keywords: particulate organic matter ; storage ; organic processing ; agriculture ; longitudinal patterns
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An agriculturally-impacted stream in northern Idaho was examined over a two-year period to determine seasonal and longitudinal patterns of the storage and decomposition of particulate organic matter. Biomass of benthic organic matter (BOM) was considerably less than values reported in the literature for comparable, undisturbed streams. Coarse, fine, and total benthic particulate organic matter were not correlated with parameters pertaining to stream size (e.g., stream order), but were correlated with sample site and amount of litterfall. The association of BOM with site and litterfall suggests that storage of particulate organic matter is a function of local characteristics rather than stream size. Low biomass of stored organic matter is a response to the low input of terrestrially-derived organic matter resulting from removal of climax vegetation. Leaf packs of alder, Alnus sp., were placed in the stream seasonally for 30 and 60 d. While there were significant differences for months, there was no significant difference among sites for leaf packs exposed for 30 d. Significant differences were observed among both sites and months for leaf packs exposed for 60 d; however, differences among sites accounted for only 5% of the variance. The absence of differences in decomposition of organic matter along the gradient of Lapwai Creek, despite heterogeneity of the drainage basin and availability of organic matter, may be in response to the overall low biomass of stored benthic organic matter. This study demonstrates that agricultural activity can substantially influence instream heterotrophic processes through reduced availability of organic matter and can shape community structure and ecosystem dynamics of streams flowing through agricultural drainage basins.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    Springer
    Journal of aquatic ecosystem stress and recovery 3 (1994), S. 207-219 
    ISSN: 1573-5141
    Keywords: Kattegat ; Skagerrak ; sediments ; toxicity ; Daphnia magna ; Nitocra spinipes ; Crustacea ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Superficial (0 to 2 cm) sediments were sampled from 62 sites in Kattegat and Skagerrak during autumn 1989 and spring 1990, tested for toxicity to Daphnia magna and Nitocra spinipes (Crustacea) and analyzed for heavy metals (Cd, Cr, Cu, Hg, N, Pb, Zn), nutrients (N and P) and organic carbon. Whole sediment toxicity to Nitocra spinipes, expressed as 96-h LC50, ranged from 1.8 to 〉 〉 32 percent sediment (wet wt), which is equivalent to 0.63 to 53 percent dry wt. Sediment total metal concentrations (mg kg-1 dry wt) ranged from 0.01 to 0.32 for Cd, 8 to 57 for Cr, 3 to 40 for Cu, 0.03 to 0.86 for Hg, 3 to 43 for Ni, 6 to 37 for Pb and 21 to 156 for Zn. Analyzed concentrations of heavy metals were tested for correlation with whole sediment toxicity normalized to dry wt, and significant correlations (Spearman p〈0.05) were found for Cd, Cr, Cu, Hg, and Ni. However, the analyzed concentrations of these metals were below the spiked sediment toxicity of these heavy metals to N. spinipes, except for Cr and Zn for which analyzed maximum concentrations approached the 96-h spiked sediment LC50s. There was no improvement in correlation between the sum of heavy metal concentrations normalized to their spiked toxic concentrations (Toxic Unit approach) and the whole sediment toxicity. Calculated heavy-metal-derived toxicity based on toxic units and whole sediment toxicity ranged from 0.1 to 24 (mean value 2.3 and SD 4.2). Theoretically, a value of 1.0 would explain whole sediment toxicity from measured metal concentrations using this approach. Thus, in spite of the fact that the total concentrations of the heavy metals were sufficient to cause toxicity based on an additive model for most of these sediments, the observed toxicity of the sediments from Kattegat and Skagerrak could not exclusively be explained by the concentrations of heavy metals, except for Cr and Zn at their maximum concentrations. Therefore, other pollutants than these heavy metals must also be considered as possible sediment toxicants.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Electronic Resource
    Electronic Resource
    Springer
    Biogeochemistry 14 (1991), S. 113-128 
    ISSN: 1573-515X
    Keywords: Bays ; Cuba ; estuaries ; heavy metals ; pollution ; sediments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract This paper presents data obtained between 1983 and 1989 on concentration of heavy metals in sediments of five Cuban bays having different physical and geographical characteristics and differing degrees of anthropogenic activities. Data are normalized with respect to Al, Fe, and organic content and processed through statistical techniques of multivariate analysis. The degree of heavy metal pollution among the harbors decreases in the following order: Havana, Santiago de Cuba, Cienfuegos ≈ Matanzas, Cárdenas
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    Springer
    Journal of aquatic ecosystem stress and recovery 2 (1993), S. 111-117 
    ISSN: 1573-5141
    Keywords: ecosystem ; health ; concept ; environment ; management
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Since the 1970's the management of aquatic habitats has changed from piecemeal monitoring to the ecosystem approach; this was initiated in the North American Great Lakes, comprising social, economic, and environmental aspects. The information included in this paper is based on the presentation made at the ‘Seminar On Ecosystem Approach To Water Management’ held in Oslo, Norway during 1991. Recently, the multidisciplinary, holistic, and integrated concept of ecosystem health has emerged, and is being advanced for the implementation of an ecosystem approach to environmental management, which has resulted in the formation of an international society (Aquatic Ecosystem Health & Management Society) and the publication of a primary journal (Journal of Aquatic Ecosystem Health). The information has been updated to incorporate new developments and recent progress about the Society and the journal since the Oslo Seminar.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    Springer
    Genetica 93 (1994), S. 149-160 
    ISSN: 1573-6857
    Keywords: environment ; genome ; stress ; transposable elements ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The action of stresses on the genome can be considered as responses of cells or organisms to external aggressions. Stress factors are of environmental origin (climatic or trophic) or of genomic nature (introduction of foreign genetic material, for example). In both cases, important perturbations can occur and modify hereditary potentialities, creating new combinations compatible with survival; such a situation may increase the variability of the genome, and allow evolutive processes to take place. The behavior of transposable elements under stress conditions is thus of particular interest, since these sequences are sources of mutations and therefore of genetic variability; they may play an important role in population adaptation. The survey of the available experimental results suggests that, although some examples of mutations and transposable elements movements induced by external factors are clearly described, environmental injuries or introduction of foreign material into a genome are not systematically followed by drastic genomic changes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell, tissue and organ culture 32 (1993), S. 319-328 
    ISSN: 1573-5044
    Keywords: calcium chelator ; calmodulin antagonist ; growth cycle ; heavy metals ; peanut cells ; peroxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During the normal growth cycle of peanut (Arachis hypogaea L.) cells, cultured in suspension medium, cell aggregates of 〈0.5 mm were formed during the log phase and grew to aggregates of 〉0.5 mm during late growth phase. Calmodulin rose to its original level during 〈0.5 mm aggregate formation following an initial 50% drop. Observations by UV microscopy showed that calmodulin. Ca2+ was centered in intense fluorescent sites. Calmodulin antagonists and a calcium chelator inhibited 〈0.5 mm aggregate formation as well as protein accumulation. The chelator suppressed cationic peroxidase isozyme release, while the antagonists had some partial effect on the anionic isozyme. Some heavy metals such as cadmium, mercury, lead and cobalt at low concentrations would allow continued growth of 〉0.5 but not of the 〈0.5 populations. At high (1 mM) concentrations these ions caused arrested growth. At low (10 μM) levels and in the presence of 3 mM calcium they had a synergistic effect.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Electronic Resource
    Electronic Resource
    Springer
    Environmental and resource economics 1 (1991), S. 313-332 
    ISSN: 1573-1502
    Keywords: Manure problem ; nutrient policy ; nutrient surplus ; regulatory levy ; sustainability ; agriculture ; intensive livestock sector ; acidification ; groundwater pollution ; eutrophication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract Rapid increases in livestock production in the Netherlands have changed manure from a valuable input into a mere waste product. This is especially true for the southern and eastern parts of the country, where specialized pig and poultry farms have concentrated on sandy soils. As these farms generally own very little land, they largely depend on imported feedstuffs. As a consequence, manure is applied to the land in such large quantities that serious environmental problems have resulted: (1) eutrophication of surface water by phosphate emissions; (2) pollution of groundwater by nitrate emissions; and (3) acidification by ammonia emissions. In the last few years the Dutch government has developed a manure policy to counteract these effects. Our analysis of that policy has revealed at least three fundamental defects, which render the manure policy ineffective and inefficient. In this paper proposals are made to remove the defects in current manure policy. Much attention is paid to the problem of designing a mixture of policy instruments which is both effective as well as efficient in limiting the environmental problems caused by manure. It is shown that the use of financial incentives in regulation can substantially improve the efficiency of the manure policy. Finally, the main economic consequences of the proposed policy are examined for the public sector as well as for the agricultural sector.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Electronic Resource
    Electronic Resource
    Springer
    Environmental and resource economics 2 (1992), S. 373-398 
    ISSN: 1573-1502
    Keywords: Adoption ; irrigation technology ; environment ; drainage pollution ; policy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract Modern irrigation technologies have been suggested as a means of conserving scarce water and reducing environmental pollution caused by irrigated agriculture. This paper applies an economic model of technology selection that provides a general framework to analyzing adoption of irrigation technologies under various environmental conditions. Data from the San Joaquin Valley of California is used to verify the theoretical relationships. Results suggest key variables to be considered by policy makers concerned with adoption of modern irrigation technologies. Among these variables are crop prices, water technology costs, farm organization characteristics, and the environmental conditions of the farm or the field. Policy implications were discussed and analyzed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Electronic Resource
    Electronic Resource
    Springer
    Environmental and resource economics 3 (1993), S. 285-296 
    ISSN: 1573-1502
    Keywords: Pollution control ; nitrogen taxation ; agriculture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
    Notes: Abstract Amongst possible economic incentives to encourage reduced nitrate contamination of water, this paper emphasizes a nitrogen tax as a possible solution. This finding is based on models estimated from panel data for 100 intensive livestock farms. For each farm a threshold is established (nitrogen units which can be spread per hectare without damage) above which there is an excess of nitrogen. The 100 farms can consequently be classified into two subsamples. The demand for nitrogen is derived for each sub-sample using the dual approach. Both categories are pooled together and a tobit model is estimated. This is used to derive total nitogen demand if all farms were under the threshold. A mineral nitrogen tax would lead to a reduced nitrate concentration in water supplies, because of a more efficient use of organic nitrogen together with a reduction in the use of mineral nitrogen in crop production.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 36 (1993), S. 79-90 
    ISSN: 1573-0867
    Keywords: agriculture ; Sahel ; Sudan ; Mali ; cotton ; fertilization ; nutrient ; soil ; soil degradation ; depletion ; nutrient ; nutrient balance ; nitrogen ; phosphorus ; potassium ; calcium ; magnesium ; acidification ; sustainability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The degree of soil mining by agricultural production in Southern Mali is assessed by calculating nutrient balances: differences between the amount of plant nutrients exported from the cultivated fields, and those added to the fields. Export processes include extraction by crops, losses due to leaching, to erosion, and to volatilization and denitrification. Inputs include applications of fertilizer and manure, restitution of crop residues, nitrogen fixation, atmospheric deposition of nutrients in rain and dust, and enrichment by weathering of soil minerals. Nutrient balances are calculated for N, P, K, Ca, and Mg. Both pessimistic and optimistic estimates are given. The resulting figures indicate, even when the most optimistic estimates are used, large deficits for nitrogen, potassium and magnesium. For the region as a whole, the calculated deficits are -25 kg N/ha,-20 kg K/ha, and -5 kg Mg/ha. Further, acidification is to be expected, in particular in areas where cotton is grown. The deficits are caused by traditional cereal crops, but also by cotton and especially by groundnut. The latter two crops are fertilized, but insufficiently. It is important to note, that the negative figures are not automatic recommendations for application of a specific amount of additional fertilizer. For phosphorus and calcium the balance of the region as a whole appears to be about in equilibrium, but locally large variations may occur. Erosion and denitrification are important causes of nutrient loss, accounting respectively for 17 and 22% of total nitrogen exports. Atmospheric deposition and weathering of minerals in the soil are still important nutrient inputs that contribute as much as nutrients as organic and mineral fertilizer combined. Nutrient depletion is very large in comparison to the amount of fertilizer applied. Drastic options, such as doubling the application of fertilizer or manure, or halving erosion losses, even if feasible, would still not be enough to make up for the calculated deficits. The annual value of withdrawn nutrients, if related to prices of fertilizers, varies between 10,000 and 15,000 FCFA/ha (40-60 US $/ha). Since the estimated average gross margin from farming in this area is 34,000 FCFA/ha (123 US $/ha), soil mining appears to provide an amount equal to 40% of farmers' total income from agricultural activities.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 36 (1993), S. 177-184 
    ISSN: 1573-0867
    Keywords: diffuse nutrient loss ; management ; agriculture ; fertilizer ; soil testing ; water and erosion control
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Eutrophication problems in waterbodies in south-western Australia are primarily caused by inputs of nutrients from diffuse sources within the agricultural catchments of these waterbodies. To reduce the algal growth and seagrass decline caused by these inputs, it is essential to modify land management to minimise nutrient losses. Permanent reduction in nutrient losses from agricultural catchments should involve voluntary changes in farm management practices based on improved land management. Specifically, these include on-farm nutrient management such as soil testing, fertilizer management, the use of perennial plants, and water and erosion control measures to reduce nutrient loss from rural land. This paper describes the management of nutrient loss from the catchment of Oyster Harbour on the south coast of Western Australia using a co-operative approach.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 27 (1991), S. 39-47 
    ISSN: 1573-0867
    Keywords: Liming ; dolomite ; Norway spruce ; nitrate ; heavy metals ; DOC
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 40 (1994), S. 149-154 
    ISSN: 1573-0867
    Keywords: heavy metals ; ionic composition ; 15N- and32P-tracer ; plant nutrients ; pot experiment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Stored human urine had pH values of 8.9 and was composed of eight main ionic species (〉 0.1 meq L−1), the cations Na, K, NH4, Ca and the anions, Cl, SO4, PO4 and HCO3. Nitrogen was mainly (〉 90%) present as ammoniacal N, with ammonium bicarbonate being the dominant compound. Urea and urate decomposed during storage. Heavy metal concentrations in urine samples were low compared with other organic fertilizers, but copper, mercury, nickel and zinc were 10–500 times higher in urine than in precipitation and surface waters. In a pot experiment with15N labelled human urine, higher gaseous losses and lower crop uptake (barley) of urine N than of labelled ammonium nitrate were found. Phosphorus present in urine was utilized at a higher rate than soluble phosphate, showing that urine P is at least as available to crops as soluble P fertilizers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 34 (1993), S. 59-65 
    ISSN: 1573-0867
    Keywords: Barley ; environment ; nitrogen ; seeding rate ; yield ; yield components
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract This study was conducted to determine the effects of rainfall and temperature during the growing season, seed rate, and N rate on grain yield and yield components of winter barley (Hordeum vulgare L.) on a Typic Haploxeralf soil in Santa Olalla (Toledo), Spain in 1986/7, 1987/8, and 1988/9. Two experiments were conducted each year using the 6-rowed variety ‘Barbarrosa’ and the 2-rowed variety ‘Reinette’. Both experiments used seed rates of 80, 160, and 240 kg ha−1 as whole plot treatments, and N rates of 0, 40, 80, 120, and 160 kg ha−1 as subplots. Responses to N depended on both the quantity and distribution of rainfall during the growing season, and temperature during grain fill. In the high rainfall, moderate grain-fill temperature year, increasing the N rate from 0 to 160 kg ha−1 increased grain yields (by 2.3 t ha−1), straw yields and the harvest index while maintaining the kernel weight for both varieties. In the low rainfall, high grain-fill temperature year, N rate had little influence on grain yield, but increased the straw yield, which reduced the harvest index, and also decreased kernel weight. Seed rate had no influence on grain yields even though wide variation in N rates, rainfall and temperatures occurred in the three-year study. Results from this study indicated that strategies to reduce (or avoid) water/high temperature stress during grain fill are necessary to assure more uniform yield responses to N application across years. However, decisions about seed rate can be made independently for conditions similar to those in this study.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 14 (1992), S. 205-222 
    ISSN: 1573-0662
    Keywords: Antarctica ; snow ; lead ; heavy metals ; global pollution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Concentrations of Pb, Cd, Cu and Zn have been measured using improved ultraclean procedures in a succession of twenty six snow samples integrating a 40 yr time sequence from 1940 to 1980 which were collected from the walls of a 6 m deep pit at stake D 55 in Adelie Land, East Antarctica. Measured concentrations, which are among the lowest ones ever measured in Antarctic snows, are found not to have significantly increased during the investigated time period, with the possible exception of Pb for which there might have been a significant increase after the mid 1960's. For this last metal, measured concentrations in the 1940's are about 6-fold higher than in Antarctic Holocene ice several thousand years old, which indicates that a large fraction of the anthropogenic increase for Pb probably occurred before the 1940's.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...