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Wilckens W. Brückner Wasmund Leuchs Bubnoff 《International Journal of Earth Sciences》1936,27(4):393-397
Ohne Zusammenfassung 相似文献
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N. Wasmund 《洁净——土壤、空气、水》1984,12(3):255-272
For the determination of the contents of chlorophyll a and phaeopigment a in sediment samples the method according to LORENZEN with its principle and the error sources is discussed in detail. The acidification required for the determination of the phaeopigments should be carried out on a final concentration of 0.006 mol/l acid. As an extracting agent, such a quantity of acetone has to be added to the sediment sample that a final concentration of 90 % acetone will be obtained with the interstitial water being taken into account. By an extraction done twice 90 % of pigments are extracted. Methanol as an extracting agents is unsuitable for several reasons mentioned. Exposure to light at more than 1 W/m2 results in a high rate of chlorophyll degradation, the same effect being shown by increased temperatures. Between the trichromatic chlorophyll determination according to JEFFREY and HUMPHREY and the determination according to LORENZEN exists the linear relation chl. a (J. and H.)=chl. a (L.)+0.6. phaeo. a (L.). The procedure of the determination of chlorophyll a and phaeopigment a according to LORENZEN is described in a detailed representation. 相似文献
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N. Wasmund A. Andrushaitis E.
ysiak-Pastuszak B. Müller-Karulis G. Nausch T. Neumann H. Ojaveer I. Olenina L. Postel Z. Witek 《Estuarine, Coastal and Shelf Science》2001,53(6):849
Primary production, nutrient concentrations, phytoplankton biomass (incl. chlorophyll a) and water transparency (Secchi depth), are important indicators of eutrophication. Earlier basin-wide primary production estimates for the Baltic Sea, a shallow shelf sea, were based mainly on open-sea data, neglecting the fundamentally different conditions in the large river plumes, which might have substantially higher production. Mean values of the period 1993–1997 of nutrient concentrations (phosphate, nitrate, ammonium and silicate), phytoplankton biomass, chlorophyll a (chl a) concentration, turbidity and primary production were calculated in the plumes of the rivers Oder, Vistula and Daugava and Klaipeda Strait as well as the open waters of the Arkona Sea, Bornholm Sea, eastern Gotland Sea and the Gulf of Riga. In the plumes, these values, except for primary production, were significantly higher than in the open waters. N:P ratios in the plumes were >16 (with some exceptions in summer and autumn), indicating potential P-limitation of phytoplankton growth, whereas they were <16 in the open Baltic Proper, indicating potential N-limitation. On the basis of in situ phytoplankton primary production, phytoplankton biomass and nutrient concentrations, the large river plumes and the Gulf of Riga could be characterized as eutrophic and the outer parts of the coastal waters and the open sea as mesotrophic. Using salinity to define the border of the plumes, their mean extension was calculated by means of a circulation model. Taking into account the contribution of coastal waters, the primary production in the Baltic Proper and the Gulf of Riga was 42·6 and 4·3×106 t C yr−1, respectively. Hence, an annual phytoplankton primary production in the whole Baltic Sea was estimated at 62×106 t C yr−1. The separate consideration of the plumes had only a minor effect on the estimation of total primary production in comparison with an estimate based on open sea data only. There is evidence for a doubling of primary production in the last two decades. Moreover, a replacement of diatoms by dinoflagellates during the spring bloom was noticed in the open sea but not in the coastal waters. A scheme for trophic classification of the Baltic Sea, based on phytoplankton primary production and biomass, chl a and nutrient concentrations, is proposed. 相似文献
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Monika Nausch Günther Nausch Hans Ulrich Lass Volker Mohrholz Klaus Nagel Herbert Siegel Norbert Wasmund 《Estuarine, Coastal and Shelf Science》2009,83(4):434-442
In July 2007, phosphorus input by an upwelling event along the east coast of Gotland Island and the response of filamentous cyanobacteria were studied to determine whether introduced phosphorus can intensify cyanobacterial bloom formation in the eastern Gotland Basin. Surface temperature, nutrient concentrations, phytoplankton biomass and its stoichiometry, as well as phosphate uptake rates were determined in two transects between the coasts of Gotland and Latvia and in a short grid offshore of Gotland. In the upwelling area, surface temperatures of 11–12 °C and average dissolved inorganic phosphorus (DIP) concentrations of 0.26 μM were measured. Outside the upwelling, surface temperatures were higher (15.5–16.6 °C) and DIP supplies in the upper 10 m layer were exhausted. Nitrite and nitrate concentrations (0.01–0.22 μM) were very low within and outside the upwelling region. Abundances of filamentous cyanobacteria were highly reduced in the upwelling area, accounting for only 1.4–6.0% of the total phytoplankton biomass, in contrast to 18–20% outside the upwelling. The C:P ratio of filamentous cyanobacteria varied between 32.8 and 310 in the upwelling region, most likely due to the introduction of phosphorus-depleted organisms into the upwelling water. These organisms accumulate DIP in upwelling water and have lower C:P ratios as long as they remain in DIP-rich water. Thus, diazotrophic cyanobacteria benefit from phosphorus input directly in the upwelling region. Outside the upwelling region, the C:P ratios of filamentous cyanobacteria varied widely, between 240 and 463, whereas those of particulate material in the water ranged only between 96 and 224. To reduce their C:P ratio from 300 to 35, cyanobacteria in the upwelling region had to take up 0.05 mmol m−3 DIP, which is about 20% of the available DIP. Thus, a larger biomass of filamentous cyanobacteria may be able to benefit from a given DIP input. As determined from the DIP uptake rates measured in upwelling cells, the time needed to reduce the C:P ratio from 300 to 35 was too long to explain the huge bloom formations that typically occur in summer. However, phosphorus uptake rates increased significantly with increasing C:P ratios, allowing phosphorus accumulation within 4–5 days, a span of time suitable for bloom formation in July and August. 相似文献
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Kraberg AC Wasmund N Vanaverbeke J Schiedek D Wiltshire KH Mieszkowska N 《Marine pollution bulletin》2011,62(1):7-20
Regime shifts in the marine environment have recently received much attention. To date, however, few large-scale meta-analyses have been carried out due to insufficient data coverage and integration between sustained observational datasets because of diverse methodologies used in data collection, recording and archival. Here we review the available data on regime shifts globally, followed by a review of current and planned policies with relevance to regime shifts.We then focus on the North and Baltic Seas, providing examples of existing efforts for data integration in the MarBEF Network of Excellence. Existing gaps in data coverage are identified, and the added value from meta-analyses of multiple datasets demonstrated using examples from the MarBEF integrated data project LargeNet. We discuss whether these efforts are addressing current policy needs and close with recommendations for future integrated data networks to increase our ability to understand, identify and predict recent and future regime shifts. 相似文献
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Phytoplankton trends in the Baltic Sea 总被引：9，自引：2，他引：9
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Erich Wasmund 《International Journal of Earth Sciences》1929,20(4-5):295-319
Zusammenfassung Die nördlichen pontischen Gestade sind durch eine Reihe erdgeschichtlich junger Gebilde wie die Limane mit ihren Nehrungen, die Salzseeketten und Schillriffe vor den übrigen Küsten des Schwarzen Meeres ausgezeichnet. Die zu ihrer Entstehungsgeschichte herangezogenen Bodenbewegungen werden strukturell als zugehörig dem tektonisch vorgebildeten und einheitlichen Streifen einer Saumtiefe vor der endgültig abgesunkenen Vortiefe des Pontus aufgefa\t. Der Existenznachweis und die zeitliche Festlegung der postdiluvialen im PleistozÄn wurzelnden Krustenbewegungen wird durch die eingehende Behandlung einer subfossilen Molluskenfauna versucht. Sie ist für die ausführlicher beschriebene Riesennehrung des Arabat an der Asowschen Westküste neu, und wird mit mehreren teilweise bekannten, teils auch unpublizierten Faunen parallelisiert. Die Befunde erlauben weitere Rückschlüsse auf tektonische, klimatische und hydrographische VerÄnderungen des südrussischen QuartÄrs und werden an den bisherigen Ergebnissen geprüft.Als Anhang folgen einzelne biostratonomische Beobachtungen aus dem im ersten Teil erdgeschichtlich zusammenhÄngend behandelten südrussischen Gebiet und seiner Umgebung. Wellenfurchen aus einem Odessaer Liman werden abgebildet. Verschiedenste bionomische Typen von Thanatocönosen werden kurz beschrieben, an rezenten seien genannt: Brackwasser (Salzseen, Kaspimeer), Land (Steppe, Krimgebirge), Flu\ (Wolga), an fossilen werden Flachseebeobachtungen aus dem südrussischen Sarmat im Anschlu\ an Ähnliche jüngst bekannt gewordene aus rumÄnischen ponto-sarmatischen Ablagerungen behandelt. 相似文献