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61.
Villy Christensen Carl J. Walters Robert Ahrens Jacqueline Alder Joe Buszowski Line Bang Christensen William W.L. Cheung John Dunne Rainer Froese Vasiliki Karpouzi Kristin Kaschner Kelly Kearney Sherman Lai Vicki Lam Maria L.D. Palomares Aja Peters-Mason Chiara Piroddi Jorge L. Sarmiento Jeroen Steenbeek Rashid Sumaila Reg Watson Dirk Zeller Daniel Pauly 《Ecological modelling》2009
We present a new methodology for database-driven ecosystem model generation and apply the methodology to the world's 66 currently defined Large Marine Ecosystems. The method relies on a large number of spatial and temporal databases, including FishBase, SeaLifeBase, as well as several other databases developed notably as part of the Sea Around Us project. The models are formulated using the freely available Ecopath with Ecosim (EwE) modeling approach and software. We tune the models by fitting to available time series data, but recognize that the models represent only a first-generation of database-driven ecosystem models. We use the models to obtain a first estimate of fish biomass in the world's LMEs. The biggest hurdles at present to further model development and validation are insufficient time series trend information, and data on spatial fishing effort. 相似文献
62.
An evaluation of the degradation of soils can be performed in several ways. Here, one way will be demonstrated beginning with the definition of the objects which are to be evaluated, continued with the definition of protection aims and the derivation of indicators. Objects together with indicators provide the frame within which a multicriteria assessment, has to be performed. Often no deterministic quality function is available, so that the concept of partially ordered sets is suggested. This concept is demonstrated by an example of an evaluation exercise performed for the environmental protection agency in Baden Württemberg. A result is that the use of arbitrarily defined quality functions may lead to erroneous statements. 相似文献
63.
As it is practically impossible in an industrial society to reduce impacts into ecosystems to a level that would preclude any damages, the need for damage valuation arises. One of the available valuation tools is the economic approach. Subsequent publications present this approach using the example of soils. In the first part, soils as part of ecosystems are considered from an ecological and a conventional economic point of view. In the following so-called ecological-economic perspective, more recent developments in economic valuation research are introduced. It is shown how ecological and economic valuation can complement one another. It is emphasized that economic valuations should be restricted to a critical soil structure which, in economic terms, is determined by the non-substitutable services of the ecological asset. 相似文献
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66.
DM Peter Lorenz Rainer Bollmann Georg Klaus Hinkel Marco Mächler Gabriele Siegert Gudrun Stamminger Jörg Wendisch Sabine Ziemer 《黑龙江环境通报》1991,11(11):819-825
The study of the fetal platelet count and size can, according to the literature, be used for the prenatal diagnosis of the Wiskott-Aldrich syndrome (WAS). So far, no affected fetuses have been identified by this method. All pregnancies in which this method had been applied to resulted, as correctly predicted, in the birth of normal children. Here we report on a familial case of WAS where the haematological parameters failed to reveal the affected second child. Hence we assume that the platelet count and size of platelets remain normal in fetuses with WAS to the gestational age of 22 weeks and cannot be used for prenatal diagnosis. 相似文献
67.
Dr. Ulrich Gembruch Molly Chatterjee Rainer Bald Gerd Eldering Helga Göcke Andreas E. Urban Manfred Hansmann 《黑龙江环境通报》1990,10(4):211-217
A case of aortic atresia with insufficiency of mitral valve diagnosed prenatally at 33 weeks of gestation is presented. An accurate diagnosis of this fetal cardiovascular malformation was possible by application of Doppler colour flow mapping, which demonstrated (a) the absence of forward flow in the hypoplastic ascending aorta, (b) reverse flow of blood from the ductus arteriosus into the severely hypoplastic ascending aorta in the late systole, (c) pansystolic mitral valve regurgitation, and (d) absent flow across the foramen ovale as a result of premature closure of the foramen ovale. 相似文献
68.
This report of an international conference about the problems around lakeshores, their evaluation and the possibilities to improve the situation for lake shores, continues the series ‘Lake shores, a forgotten ecotone’ as article 4. Five main topics were discussed: (1) applied ecology of lakeshores, (2) human impact, (3) ecological assessment, (4) protection and restoration, (5) sustainable development and use of lake shores. 相似文献
69.
For the assessment of contaminated and remediated soils and substrates, and the estimation of chronic toxicity of soil contaminations, an ecotoxicological test was developed using the terrestrial nematodePanagrellus redivivus. The population dynamics expressed by the reproduction factor (VF) allows an estimation of soil quality within seven days. Due to the rapid generation time ofPanagrellus (< 5 d), the short test duration is considered to be sufficient. The suitability of this test duration is considered to be sufficient. The suitability of this test was evaluated by investigating soils which had been contaminated using applications of specific pollutants (lindane and PCB 52). 相似文献
70.
Bernd Markert Rainer Steinbeck Karl-Josef Nick Karl-Georg Bernhardt 《Environmental geochemistry and health》1990,12(3):239-244
The concentrations of Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sr, Ti, V and Zn were determined by AES/ICP inMolinia caerulea andEriophorum vaginatum grown in the Leegmoor, which is in reinstatement. In the soil substrate analytical detection limits were obtained for Ag, Co, Li, Mo and Rb and additionally for Al, Be, Cd, Cr, La, Li, Ni, Pb, Ti and V in plants. Compared with mineral soils, the concentration of elements in peat is low. The elements K and P were enriched byMolinia caerulea andEriophorum vaginatum, and in addition Mn and Zn byEriophorum vaginatum. Altogether the ability of accumulation essential elements seem to be more efficient byEriophorum vaginatumthan byMolinia caerulea, which can be an ecophysiological advantage on peats, whereMolinia caerulea is normally not distributed. 相似文献