ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Articles  (91)
  • paleolimnology  (64)
  • earthquakes  (27)
  • 2000-2004  (12)
  • 1990-1994  (79)
  • Geosciences  (91)
  • Technology
Collection
  • Articles  (91)
Source
Keywords
Publisher
Years
Year
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Paleolimnological reconstruction of recent changes in assemblages of Cladocera from acidified lakes in the Adirondack Mountains (New York) (1994)
    Springer
    Journal of paleolimnology 11 (1994), S. 189-200 
    Details
    ISSN: 1573-0417
    Keywords: paleolimnology ; lake acidification ; Cladocera ; Chydoridae ; Adirondack Mountains
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Remains of Cladocera were examined in short sediment cores from three Adirondack lakes with mean pHs below 5 and a fourth with a mean pH of 6.5. These cores were collected as part of the Paleoecological Investigation of Recent Lake Acidification (PIRLA I) project. Historical and paleolimnological evidence suggests that pH has decreased in each of the acid lakes in recent decades. In all of the study cores, the greatest changes in net accumulation rates, assemblage composition, and species richness occurred in recently deposited sediments. The similar timing of events in all lakes suggests that a regional disturbance was responsible. In the three acid lakes, there was a strong association of changes in cladoceran assemblages and diatom, chrysophyte, and geochemical evidence of acidification. The occurrence of recent changes in non-acid Windfall Pond indicates that other factors may also have affected Cladocera in the study lakes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00686865
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles (1994)
    Springer
    Journal of paleolimnology 12 (1994), S. 171-179 
    Details
    ISSN: 1573-0417
    Keywords: diatoms ; methods ; absolute abundance ; microfossils ; paleolimnology ; paleoceanography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract The determination of absolute abundances of diatoms in paleolimnological and paleoceanographic studies is now becoming a routine step in diatom paleoecological investigations. Several distinct methods have been described for establishing absolute diatom abundance. Each of these methods has its own strengths and weaknesses. The most common weakness in diatom preparation methods is the use of aliquot subsampling from an assumed ‘well-mixed’ diatom suspension. Described here is a simple, efficient and inexpensive method that utilizes settling of diatoms through a 10 cm water column, which yields an effectively random distribution, and uses no aliquot subsampling. Only a few milligrams of sample are needed, permitting microstratigraphic analysis of, for example, individual varves. The method is shown to be both reproducible and accurate for sediments ranging in diatom concentration from less than 10 million to more than one billion diatoms per gram. Multiple slides or SEM stubs can be simultaneously prepared. The method works well for the analysis of most silt-sized microfossils or other sedimentary particles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00678093
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Diatom-salinity relationships in 111 lakes from the Interior Plateau of British Columbia, Canada: the development of diatom-based models for paleosalinity reconstructions (1994)
    Springer
    Journal of paleolimnology 12 (1994), S. 197-221 
    Details
    ISSN: 1573-0417
    Keywords: diatoms ; paleolimnology ; paleoclimatology ; salinity ; athalassic ; British Columbia ; CCA ; transfer function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Diatoms were identified and enumerated from the surface sediments of 111 lakes, 45 from the Kamloops region and 66 from the Cariboo/Chilcotin region, located on the southern Interior Plateau of British Columbia, Canada. This paper is an extension of another study which investigated the relationship of diatoms to salinity and ionic composition in 65 lakes from the Cariboo/Chilcotin region. The 111 lakes spanned a large gradient in salinity, ranging from fresh through hypersaline (late-summer salinity values ranged from 0.04 to 369 g l−1), and included both carbonate- and sulphate-dominated lakes with sodium and magnesium as the dominant cations. The Kamloops region had more sulphate-dominated, hypersaline lakes and fewer carbonate-rich lakes than the Cariboo/Chilcotin region. Most lakes had higher salinities in the late-summer compared to the spring. Both salinity and brine-type were important variables that could explain the different diatom assemblages present in the lakes. The majority of diatom taxa had salinity optima in the freshwater to subsaline range (〈3 g l−1), and the taxa displayed a range of both narrow and broad tolerances along the salinity gradient. Weighted-averaging regression and calibration, and maximum likelihood techniques were used to develop salinity inference models from the diatom assemblages based on their relationship to the spring, late-summer and average lakewater salinity measurements. Simple weighted-averaging (WA) models generally produced the same or lower bootstrapped RMSEs of prediction than weighted-averaging with tolerance downweighting (WA(tol)) in the two regional and the combined datasets. Weighted averaging partial least squares (WA-PLS) showed little or no improvement in the predictive abilities of the datasets, as judged by the jackknifed RMSE of prediction. In all cases, the combined dataset of 102 lakes performed better than either of the smaller regional datasets, with relatively little difference between spring, average and late-summer salinity models. The maximum likelihood models gave lower apparent RMSEs of prediction in comparison to other methods; however, independent validation of this technique using methods such as bootstrapping were not undertaken because of the computer intensive nature of such analyses. These diatom-based salinity models are now available for reconstructing salinity and climatic trends from appropriately chosen closed-basin lakes in the Interior region of British Columbia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00678021
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A Holocene paleoenvironmental history of Lake Alexandria, South Australia (1994)
    Springer
    Journal of paleolimnology 12 (1994), S. 259-268 
    Details
    ISSN: 1573-0417
    Keywords: sediments ; 14C ; 210Pb ; diatoms ; geochemical analyses ; coastal paleoenvironments ; paleolimnology ; Nodularia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract An investigation of Holocene sediments within Lake Alexandrina, a shallow coastal lake at the mouth of the Murray River, South Australia, is presented based on a multidisciplinary approach.14C and210Pb radiometric dating methods are used to establish a geochronological framework for the last 7000 yr BP, and diatoms, sand-siltclay ratios, organic carbon, phosphorus and copper concentrations are used to infer paleoenvironmental changes. The diatom assemblages indicate a change from marine-brackish to oligosaline-freshwater conditions between 7000 and 6000 yr BP, with sea-level stabilisation and continuous barrier formation across the Murray mouth. Sand pulses after 2300 yr BP document sand spit formation in the lake and the commencement of extensive lacustrine sedimentation. In the past 100 years which include the advent of European settlement in the region, the short-term210Pb-based mass accumulation rate of 0.063 g cm−2 yr−1 is greater than that of the longer-term mean14C-based rate (0.023 g cm−2 yr−1), and high concentrations of phosphorus and copper correspond to historical records of blue-green algal blooms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00678024
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Paleohydrology and paleochemistry of Lake Manitoba, Canada: the isotope and ostracode records (1994)
    Springer
    Journal of paleolimnology 12 (1994), S. 269-282 
    Details
    ISSN: 1573-0417
    Keywords: Great Plains ; western Canada ; magnesian calcite ; Holocene ; paleolimnology ; stable isotopes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Lake Manitoba, the largest lake in the Prairie region of North America, contains a fine-grained sequence of late Pleistocene and Holocene sediment that documents a complex postglacial history. This record indicates that differential isostatic rebound and changing climate have interacted with varying drainage basin size and hydrologic budget to create significant variations in lake level and limnological conditions. During the initial depositional period in the basin, the Lake Agassiz phase (∼12–9 ka), δ18O of ostracodes ranged from −16‰ to −5‰ (PDB), implying the lake was variously dominated by cold, dilute glacial meltwater and warm to cold, slightly saline water.Candona subtriangulata, which prefers cold, dilute water, dominates the most negative δ18O intervals, when the basin was part of proglacial Lake Agassiz. At times during this early phase, the δ18O of the lake abruptly shifted to higher values; euryhaline taxa such asC. rawsoni orLimnocythere ceriotuberosa, and halobiont taxa such asL. staplini orL. sappaensis are dominant in these intervals. This positive covariance of isotope and ostracode records implies that the lake level episodically fell, isolating the Lake Manitoba basin from the main glacial lake. δ18O values from inorganic endogenic Mg-calcite in the post-Agassiz phase of Lake Manitoba trend from −4‰ at 8 ka to −11‰ at 4.5 ka. We interpret that this trend indicates a gradually increasing influence of isotopically low (−20‰ SMOW) Paleozoic groundwater inflow, although periods of increased evaporation during this time may account for zones of less negative isotopic values. The δ18O of this inorganic calcite abruptly shifts to higher values (−6‰) after ∼4.5 ka due to the combined effects of increased evaporative enrichment in a closed basin lake and the increased contribution of isotopically high surface water inflow on the hydrologic budget. After ∼2 ka, the δ18O of the Mg-calcite fluctuates between −13‰ and −7‰, implying short-term variability in the lake's hydrologic budget, with values indicating the lake varied from outflow-dominated to evaporation-dominated. The δ13C values of Mg-calcite remain nearly constant from 8 to 4.5 ka and then trend to higher values upward in the section. This pattern suggests primary productivity in the lake was initially constant but gradually increased after 4.5 ka.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00678025
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Chrysophycean cysts in Sierra Nevada (California) lake sediments: paleoecological potential (1992)
    Springer
    Journal of paleolimnology 7 (1992), S. 73-94 
    Details
    ISSN: 1573-0417
    Keywords: acidification ; Chrysophyceae ; cyst ; paleolimnology ; Sierra Nevada ; statospore ; stomatocyst
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Thirty-three lakes in the Sierra Nevada range of California were investigated as part of a paleoecological study of the potential effects of acid deposition on sensitive lake/watershed ecosystems. Chrysophyte cysts from surface sediment samples were analyzed and compared with data on pH and alkalinity. This paper identifies the twenty-five dominant chrysophyte cyst taxa and provides information on their morphology, abundance, distribution and ecology. Chrysophycean cysts were generally abundant and well-preserved in lake sediments of our study sites. Twelve taxa occurred in more than twenty of the thirty-three lakes; these taxa were often quite abundant. In contrast, only nine taxa occurred in ten or fewer lakes. Abundance Weighted Mean (AWM) pH varied from 6.45 to 8.34 and AWM alkalinity varied from 46 to 588 μeq/L. We delineated pH preference categories, based on AWM pH values and frequency diagrams of cyst abundance vs. lake-water pH. We classified five taxa as acidophilous, nine as circumneutrals, six as alkaliphilous and five as indifferent. Given that the cyst types differ greatly in their abundance relative to pH and alkalinity, it is clear that they have potential for paleolimnological studies of Sierra lakes biogeochemistry.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00197032
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    A simple, inexpensive piston corer for collecting undisturbed sediment/water interface profiles (1992)
    Springer
    Journal of paleolimnology 7 (1992), S. 157-161 
    Details
    ISSN: 1573-0417
    Keywords: coring device ; paleolimnology ; sediments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00196870
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Simple gravity corer suitable for educators (1992)
    Springer
    Journal of paleolimnology 7 (1992), S. 253-255 
    Details
    ISSN: 1573-0417
    Keywords: paleolimnology ; paleoecology ; limnology ; coring ; sediments ; education
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Instructions for construction and use of a simple and inexpensive sediment coring device are presented. The sampler is suitable for use in high school and undergraduate science courses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00181717
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Stratigraphy of total metals in PIRLA sediment cores (1992)
    Springer
    Journal of paleolimnology 7 (1992), S. 191-214 
    Details
    ISSN: 1573-0417
    Keywords: geochemistry ; metals ; lake sediments ; paleolimnology ; United States
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Sediment cores from 30 low-alkalinity lakes in northern New England (NE), New York (NY), the northern Great Lakes States (NGLS) of Minnesota, Michigan, and Wisconsin, and Florida (FL) have been dated by 210Pb and analyzed for water and organic content, eight major elements (Al, Ti, Fe, Mn, Ca, Mg, Na, K) plus four trace metals (Pb, Zn, Cu, and V). Variations in the percentages of major elements through time are dominated by long-term independent variations in the abundance of SiO2, FeO, and to a lesser extent Ca and Al. Additional variations are caused by varying proportions of inorganic matter. Major variations in chemistry are generally unrelated to documented distrubances in the watersheds; most disturbances are minor fires or selective logging. Accelerated accumulation of Pb from atmospheric sources into sediment first occurs in sediment dated between 1800 and 1850 in NY and NE, slightly later in the NGLS region, and about 1900 in FL. Modern accumulation rates in all areas are comparable (ca. 1 to 4 μg cm−2 yr−1). Accumulation rates of Pb in some lakes have declined significantly from 1975 to 1985. Atmospheric deposition of anthropogenic Zn and Cu is also indicated by generally increasing accumulation rates in sediment cores, but the record is not as clear nor are chemical profiles in all lakes parallel to the trends in atmospheric emissions inferred on the basis of fossil fuel consumption, smelting, and other industrial activities. Inter-lake variations in profiles of Cu and Zn are large. Vanadium accumulation rates increase by the 1940s in NY and NE, but not until the 1950s in the NGLS region. This timing correlates with regional trends in the combustion of fuel oil, a major source of atmospheric V. Acidification of some of the lakes is suggested by decreases in the concentration and accumulation rates of Mn, Ca, and Zn in recent sediment, relative to other elements of catchment origin. The decreases generally occur slightly before the onset of acidification as indicated by diatoms. Increased sediment accumulation rates for Fe may indicate the acidification of watershed soils. The use of the accumulation rate of TiO2 as an indicator of rates of erosion and for normalization of trace metal accumulation rates is in question for lakes where the flux of TiO2 from the atmosphere varies and is a significant fraction of the total flux of TiO2 to the sediment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00181714
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    A review of factors that regulate carotenoid and chlorophyll deposition and fossil pigment abundance (1993)
    Springer
    Journal of paleolimnology 9 (1993), S. 109-127 
    Details
    ISSN: 1573-0417
    Keywords: paleolimnology ; carotenoid ; chlorophyll ; pigment ; sediment ; fossil ; degradation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract Limnological surveys show that fossil pigment concentration is an accurate predictor of algal production. However, experimental and mass flux studies indicate that 〉90% of pigment is degraded to colourless compounds before permanent burial. To reconcile these views, this paper reviews current literature on pigment degradation and proposes a hierarchical control model for pigment deposition and fossil abundance. Over the widest range of production, pigment deposition and fossil concentration are proportional to algal standing crop. However, within a narrower range, the actual concentration of pigment in sediments is regulated by photo- and chemical oxidation. Three phases of loss exist: rapid oxidation in the water column (T1/2=days); slower post-depositional loss in surface sediments (T1/2=years); and very slow loss of double bonds in deep sediments (T1/2=centuries). Despite losses during deposition, fossil and algal abundance remain correlated through time, so long as there is no change in basin morphometry, light penetration, stratification or deepwater oxygen content. At the finest scale, food-web processes can increase the preservation of pigments from edible algae by incorporating pigments into feces that sink rapidly and bypass water column losses. As a consequence of selective loss during deposition and initial burial, carotenoid relative abundance is an unreliable measure of phytoplankton community composition. Instead, absolute concentration — scaled to the historical maximum — should be used for fossil interpretations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00677513
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...