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171.
Alfred Eberhardt 《Environmental management》1990,14(2):151-160
Previous comparative studies on environmental policies in the East and West mainly focused on relating differing features
of environmental management to different political, social/economic, and ideological conditions in both systems. The present
article attempts to identify common experiences. In this respect, an obvious similarity can be seen in the fact that environmental
management in the East and West emerged as a regulatory “command and control” approach, which was supplemented later by economic
incentives. The 1988 USSR Resolution “On the Radical Transformation of the System of Natural Conservation” introduces a set
of economic instruments as one of its main elements. This is less a radical change of environmental policy than a determined
acceleration of previous approaches. Existing and newly designed economic methodologies provoke a comparison with similar
approaches in market economies. The economic methods designed in the 1988 resolution include charges for the use of natural
resources and the emission of pollutants, which are notable for their firm commitment to reduce emissions even below set regulatory
standards. While experiences with this approach may be of great interest for Western countries, liability regulations of the
United States can be of great use for designing relevant provisions implementing the USSR resolution. A number of bilateral
treaties have demonstrated already the political relevance of an East-West exchange of experience in environmental management. 相似文献
172.
Lenwood W. Hall Jr. Alfred E. Pinkney Scott Zeger Dennis T. Burton Michael J. Lenkevich 《Journal of the American Water Resources Association》1984,20(2):235-239
ABSTRACT: The objective of this investigation was to evaluate the avoidance responses of juvenile striped bass, Morone saxatilis and Atlantic menhaden, Brevoortia tyrannus to bis (tri-n-butyltin) oxide. An avoidance responses was exhibited by striped bass at a total organic tin concentration of 24.9 μg/L. Atlantic menhaden exhibited avoidance to total organic tin concentrations of 5.5 μg/L and greater. Atlantic menhaden are generally more sensitive to toxicants than striped bass; therefore, avoidance responses reported in this study are not surprising. It is highly likely that the concentrations of total organic tin that were avoided by the test species in this study were much higher than expected environmental concentrations. Ecologically significant hazards may occur due to potential effects that unperceived or non-avoided organotin concentrations may have on behavioral responses mediated by chemosensory systems. 相似文献
173.
Singing and the establishment and maintenance of dominance hierarchies in captive brown-headed cowbirds 总被引:1,自引:0,他引:1
Alfred M. Dufty Jr. 《Behavioral ecology and sociobiology》1986,19(1):49-55
Summary The importance of singing in the establishment and maintenance of dominance rank was investigated in captive flocks of brown-headed cowbirds (Molothrus ater). Each flock consisted of 3 males and 1 female. In one experiment the two largest males in each of 4 flocks were temporarily devocalized by puncturing the interclavicular air sac just before group formation. The third male in each group was sham-operated. There was a significant tendency for the non-devocalized birds to become the dominant member of their group. Only sham-operated males sang immediately after the operation. In a second experiment, dominant males from flocks with established hierarchies were temporarily devocalized. None of these males lost their dominant positions, despite their inability to sing. These results suggest that song is important in the establishment of dominance rank; however, once established, social hierarchies may be maintained by non-vocal means, such as social inertia or individual recognition. 相似文献
174.
Willem Kruijer Alfred Stein Willem Schaafsma Sanne Heijting 《Environmental and Ecological Statistics》2007,14(4):399-410
Count data on a lattice may arise in observational studies of ecological phenomena. In this paper a hierarchical spatial model
is used to analyze weed counts. Anisotropy is introduced, and a bivariate extension of the model is presented. 相似文献
175.
Valentina Krysanova Frank Wechsung Alfred Becker Werner Poschenrieder Jan Gräfe 《Environmental Modeling and Assessment》1999,4(4):259-271
Hydrological processes and crop growth were simulated for the state of Brandenburg (Germany) using the hydrological/vegetation/water quality model SWIM, which can be applied for mesoscale river basins or regions. Hydrological validation was carried out for three mesoscale river basins in the area. The crop growth module was validated regionally for winter wheat, winter barley and maize. After that the analysis of climate change impacts on hydrology and crop growth was performed, using a transient 1.5 K scenario of climate change for Brandenburg and restricting the crop spectrum to the three above mentioned crops. According to the scenario, precipitation is expected to increase. The impact study was done comparing simulation results for two scenario periods 2022–2030 and 2042–2050 with those for a reference period 1981–1992. The atmospheric CO2 concentrations for the reference period and two scenario periods were set to 346, 406 and 436 ppm, respectively. Two different methods – an empirical one and a semi-mechanistic one – were used for adjustment of net photosynthesis to altered CO2. With warming, the model simulates an increase of evapotranspiration (+9.5%, +15.4%) and runoff (+7.0%, +17.2%). The crop yield was only slightly altered under the climate change only scenario (no CO2 fertilization effect) for barley and maize, and it was reduced for wheat (–6.2%, –10.3%). The impact of higher atmospheric CO2 compensated for climate-related wheat yield losses, and resulted in an increased yield both for barley and maize compared to the reference scenario. The simulated combined effect of climate change and elevated CO2 on crop yield was about 7% higher for the C3 crops when the CO2 and temperature interaction was ignored. The assumption that stomatal control of transpiration is taking place at the regional scale led to further increase in crop yield, which was larger for maize than for wheat and barley. The regional water balance was practically not affected by the partial stimulation of net photosynthesis due to higher CO2, while the introduction of stomatal control of regional transpiration reduced evapotranspiration and enlarged notably runoff and ground water recharge. 相似文献
176.
Rainer Haas Alfred Krippendorf Torsten C. Schmidt Klaus Steinbach und Eberhard v. L?w 《Umweltwissenschaften und Schadstoff-Forschung》1998,10(5):289-293
Zusammenfassung Arsenkampfstoffe sind in der Umwelt persistent und kontaminieren bis heute Boden und Grundwasser. In diesem Beitrag werden
die chemischen Reaktionen der Arsenkamptstoffe Diphenylarsinchlorid (CLARK I), Phenylarsindichlorid (PFIFFIKUS), Ethylarsindichlorid
(DICK) sowie von Chlorvinylarsinverbindungen (LEWISITE) dargestellt. Die M?glichkeiten der chemisch-analytischen Erfassung
dieser chemischen Kampfstoffe als Originalsubstanzen und als Thiol-Derivate werden pr?sentiert.
相似文献
177.
178.
The Science of Nature - 相似文献
179.
Alfred Kühn 《Die Naturwissenschaften》1955,42(19):529-530
180.