ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    European journal of soil science 50 (1999), S. 0 
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Understanding the natural variation of carbon within the soil, and between soil types, is crucial to improve predictive models of carbon cycling in high and mid-latitude ecosystems in response to global warming. We measured the carbon isotope distributions (12C, 13C and 14C) in soil organic matter (SOM) from Podzols, Brown Podzolic soils and Stagnohumic Gleysols from the British uplands, which were then compared with the total amounts and turnover of carbon in these soils. We did so by sampling at 2-cm intervals down six profiles of each soil type. The average amount of carbon stored in the top 28 cm of the Stagnohumic Gleysols is twice that of the other two soils. The 13C content and 14C age show a general increase with depth in all soils, and there is also a significant correlation between isotopic variation and the main pedogenic features. The latter suggests that soil-forming processes are significant in determining the carbon isotope signatures retained in SOM. Organic matter formed since 1960 is not found below 5 cm in any of the soils. Evidently organic detritus in the surface layers (LF and Oh) is rapidly mineralized. This accords with our modelled net annual C fluxes which show that more than 80% of the CO2 emanating from these soils is derived from the top 5 cm of each profile. Although these soils contain much carbon, they do not appear to assimilate and retain SOM rapidly. The mean residence time of most of their carbon is in the 2–50 years range, so the soils are fairly ineffective sinks for excess CO2 in the atmosphere. Under the predicted future ‘greenhouse’ climate, likely to favour more rapid microbial decomposition of organic materials, these soils are a potential source of CO2 and are therefore likely to accelerate global warming.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK; Malden, USA : Blackwell Science Ltd
    European journal of soil science 55 (2004), S. 0 
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Clear-cutting of forest provides a unique opportunity to study the response of dynamic controls on dissolved organic matter. We examined differences in concentrations, fluxes and properties of dissolved organic matter from a control and a clear-cut stand to reveal controlling factors on its dynamics. We measured dissolved organic C and N concentrations and fluxes in the Oi, Oe and Oa horizons of a Norway spruce stand and an adjacent clear-cutting over 3 years. Aromaticity and complexity of organic molecules were determined by UV and fluorescence spectroscopy, and we measured δ13C ratios over 1 year.Annual fluxes of dissolved organic C and N remained unchanged in the thin Oi horizon (∼ 260 kg C ha−1, ∼ 8.5 kg N ha−1), despite the large reduction in fresh organic matter inputs after clear-cutting. We conclude that production of dissolved organic matter is not limited by lack of resource. Gross fluxes of dissolved organic C and N increased by about 60% in the Oe and 40% in the Oa horizon upon clear-cutting. Increasing organic C and N concentrations and increasing water fluxes resulted in 380 kg C ha−1 year−1 and 10.5 kg N ha−1 year−1 entering the mineral soil of the clear-cut plots. We found numerous indications that the greater microbial activity induced by an increased temperature of 1.5°C in the forest floor is the major factor controlling the enhanced production of dissolved organic matter. Increasing aromaticity and complexity of organic molecules and depletion of 13C pointed to an accelerated processing of more strongly decomposed parts of the forest floor resulting in increased release of lignin-derived molecules after clear-cutting. The largest net fluxes of dissolved organic C and N were in the Oi horizon, yet dissolved organic matter sampled in the Oa horizon did not originate mainly from the Oi horizon. Largest gross fluxes in the Oa horizon (control 282 kg C ha−1) and increased aromaticity and complexity of the molecules with increasing depth suggested that dissolved organic matter was derived mainly from decomposition, transformation and leaching of more decomposed material of the forest floor. Our results imply that clear-cutting releases additional dissolved organic matter which is sequestered in the mineral soil where it has greater resistance to microbial decay.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    European journal of soil science 55 (2004), S. 0 
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The sequestration of dung carbon in soil depends on the location and rate at which it is immobilized in soil aggregates. Here C4 dung (δ13C = −16.1‰) or C3 dung (δ13C = −26.8‰) were applied to a temperate permanent pasture C3 soil (δ13C = −27.9‰). Triplicate samples were taken from C3 and C4 dung remaining at the surface, and in the 0–1 and 1–5 cm soil layers in the unamended control and under the C3 and C4 dung patches after 7, 14, 29, 42 and 70 days after the application of the dung. Macroaggregates (≥ 4 mm) at the lower depth (1–5 cm) were mechanically fractionated into surface and core fractions by a combination of shock freezing followed by wet sieving.Neither overall nor differential carbon isotope fractionation occurred in the dung remaining at the surface. The incorporation of C4 dung significantly increased the δ13C content of the 0–1 cm layer of the C3 soil. Dung C sequestration did not exceed 10% for the 0–1 cm layer and was only 20% for the whole soil (0–30 cm) during the 7-day experiment. Only 32–66% of the C from dung in the 1–5 cm layer was sequestered in the aggregates; the major proportion was initially preferentially attached to their surfaces, but incorporated into aggregates within the following 14 days. The majority of dung, however, soon resided between the aggregates, pointing to the important role of the inter-aggregate fraction in short-term C dynamics of dung in this pasture soil.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: We have sought to understand the molecular mechanisms by which dissolved organic matter (DOM) forms and soil organic matter (SOM) degrades in upland peaty gley soil under grass. Pyrolysis mass spectrometry (Py-MS) and pyrolysis gas chromatography mass spectrometry (Py-GC/MS) were applied to characterize the DOM collected from lysimeters and its parent SOM. The macromolecular organic matter in the litter and fermentation (Lf) horizon of the soil consists primarily of little decomposed lignocellulose from grass, whereas the humus (Oh) horizon is characterized by an accumulation of selectively decomposed lignocellulose material, microbial metabolites and bound fatty acids. The mineral horizon produced a relative enrichment of furan structures derived from microbial reworking of plant polysaccharides but virtually no lignin signals. A series of exceptional long chain C43 to C53 fatty acids with odd over even predominance, probably derived from mycobacteria, were also identified in the Oh horizon. Side-chain oxidation and shortening, increase of carboxyl functionality and selective removal of syringyl (S) 〉 guaiacyl (G) 〉 p-hydroxyphenyl (P) lignin units were the main reactions when lignin degraded. Compared with SOM, the DOM shows a large accumulation of more oxidized lignin and aromatic structures, especially those containing carboxylic and dicarboxylic acid functionalities and with shorter side-chain length. The polysaccharide-type compounds in the DOM were more modified (greater abundance of furan structures in pyrolysis products), and had significantly lower molecular weight and more diverse polymeric structures than did those in soils. Increased temperature and rainfall appeared to result in greater relative abundance of lignin degradation products and aromatic compounds in DOM.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    European journal of soil science 47 (1996), S. 0 
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: A combination of radiocarbon (14C) dating and biomarker analyses of the aliphatic hydrocarbons in soil lipids is proposed as a novel and improved method for studying the environmental history of peaty soils. The radiocarbon concentration of unfractionated bulk organic matter, hydrolysed soil residues and two lipid fractions (the aliphatic hydrocarbons and carboxylic acids) recovered from a stagnohumic gley soil, were compared using AMS (accelerator mass spectrometry) and radiometric 14C dating techniques. The radiocarbon ages recorded by the aliphatic hydrocarbon fractions were consistently older than those measured from the unfractionated soil, and were in most cases older than the residues remaining after acid hydrolysis. This pattern was observed at three different depths in the soil profile. The apparent age difference between the hydrocarbon fraction and its unfractionated substrate increased with depth. An abundance of long–chain n–alkanes, similar to those found in higher plant waxes, characterized the aliphatic hydrocarbon fraction from the deepest soil (at 21.5–24.5–cm depth). The radiocarbon age of this basal organic component (13470± 170 years bp) indicated that it derived from the initial re–establishment of vegetation on the local deglaciated landscape with the onset of the Windermere Interstadial (c. 14000–13000 14C years bp). Bulk organic detritus within the basal horizon dated at some 3000 years younger, and presumably as a result of the downward penetration and retention of some mobile organic residues produced later in the development of the soil profile. The survival and apparent stratigraphical stability of these recoverable aliphatic hydrocarbons provides the opportunity, via the development of AMS dating, to measure an unambiguous radiocarbon age for the origin of organic residues retained in soils and sediments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-5036
    Keywords: Betula pendula ; Nitrogen fertilisation ; CO2 concentration ; Carbon isotopic fractionation ; Lipids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effects of nitrogen (N) fertilisation and elevated [CO2] on lipid biosynthesis and carbon isotope discrimination in birch (Betula pendula Roth.) transplants were evaluated using seedlings grown with and without N fertiliser, and under two concentrations of atmospheric CO2 (ambient and ambient+250 μmol mol-1) in solar dome systems. N fertilisation decreased n-fatty acid chain length (18:0/16:0) and the ratios of α-linolenate (18:2)/linoleate (18:1), whereas elevated [CO2] showed little effect on n-fatty acid chain length, but decreased the unsaturation (18:2+18:1)/18:0. Both N fertilisation and elevated [CO2] increased the quantity of leaf wax n-alkanes, whilst reducing that of n-alkanols by 20–50%, but had no simple response in fatty acid concentrations. 13C enrichment by 1–2.5‰ under N fertilisation was observed, and can be attributed to both reduced leaf conductance and increased photosynthetic consumption of CO2. Individual n-alkyl lipids of different chain length show consistent pattern of δ13C values within each homologue, but are in general 5–8‰ more depleted in 13C than the bulk tissues. Niether nitrogen fertilisation and elevated CO2 influenced the relationship between carbon isotope discrimination of the bulk tissue and the individual lipids.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2017-11-01
    Print ISSN: 0047-2425
    Electronic ISSN: 1537-2537
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Wiley
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2015-04-18
    Description: The dissolved organic matter (DOM) quality or quantity of stream waters reflects catchment functioning. Dissolved organic matter features, pH, and Fe content in the main stream and tributaries of the forested Wüstebach catchment in Germany were examined for a 4-yr weekly sampling period (2009–2013). The catchment outlet (Wu14) discharge (Q) ranged from 0.22 to 72.5 L s –1 , with minima and maxima around the summer and winter seasons, respectively. Discharge clearly followed precipitation in the late autumn to early spring period. Dissolved organic C (DOC) values at Wu14 ranged between 0.8 and 7.4 mg L –1 , with a mean of 2.7 mg L –1 . Annual periodicities in DOC and temperature (T), and DOC and Fe concentrations were positively correlated, reflecting DOM transport via organo-mineral complexes. The watershed tributaries dominated by surficial water (Wu01, Wu08, and Wu09) exhibited relatively high DOC, Fe, pH, and specific DOC UV absorbance (SUVA) and high variability. Groundwater-dominated tributaries (Wu03, Wu12, and Wu15) had lower, less variable contents. The extremely dry 2011 spring had limited effect on stream water chemistry. Outlet (Wu14) stream water DOC reflected seasonally variable contributions of surficial water and groundwater, annually 65 vs. 35%. Critically, a 4-yr lowering of SUVA (reduction of the DOM aromaticity and increased biodegradability) was observed in headwater tributaries (Wu01 and Wu08) but not at Wu14. Our long-term spatial-temporal explicit data set, covering both tributaries and main stream water DOM quality and quantity, was critical in apportionment of contributing sources and drivers of sub- and whole-catchment stream water DOM dynamics.
    Electronic ISSN: 1539-1663
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 1998-08-01
    Print ISSN: 1001-6538
    Electronic ISSN: 1861-9541
    Topics: Natural Sciences in General
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2017-03-21
    Description: Elemental contents in catchment headwaters are indicative of the load of nutrients and minerals cycled or released from ecosystems, yet little is known about natural colloids (1–1000 nm) and especially natural nanoparticles (NNP, 1–100 nm) as nutrient carriers in forested headwater streams. We hypothesize that the majority of P is bound to NNP in forest streams but that their size and composition varies for different forested headwater systems. Four forested sites in Germany and one in Norway, which differ in total P content, were sampled for stream water and analyzed for colloids. The samples were fractionated using field flow fractionation coupled to inductively coupled plasma–mass spectrometry and an organic C detector. The results showed that NNP and colloids from all sites could be separated into three distinct fractions (approximately 1–20 nm, 〉20–60 nm, and 〉60 nm). The elemental concentrations of P, organic C, Al, Si, Fe, and Mn in the fractions differed among the five sites. However, cluster analysis showed that each fraction had unique elemental signatures with different preferential P binding partners. Phosphorus was preferentially associated with Fe in the smallest size fraction, with an increasing contribution of organic-C-associated P as the fraction size increased. The largest fraction was dominated by clay minerals. Also, the data indicated that the relative contribution of the NNP and colloidal fractions for ecosystem nutrient supply rises as total P concentrations decline. The study highlighted the still underestimated importance of NNP for matter transport in forest streams and thus P cycling.
    Electronic ISSN: 1539-1663
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    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...