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821.
Knegtering E Drees JM Geertsema P Huitema HJ Uiterkamp AJ 《Environmental management》2005,36(6):862-871
Environmental Impact Assessments (EIAs) should ideally help minimize adverse effects on biological diversity by considering
impacts of projects on wide ranges of species. This paper investigates how recent Dutch EIAs included the species comprising
animal diversity. We present results of two studies on fauna data used in the EIAs. Objectives were to determine for different
taxa (a) the relative representation of species in Environmental Impact Statements (EISs); (b) the extent to which EISs referred
to specific species and the accuracy of survey data referred to; and (c) apparent roles of different EIA actors in species
inclusion. EIAs were found to use data on various taxa but on limited numbers of species. The frequency with which taxa were
included varied significantly. Birds were most frequently included, followed by mammals, amphibians, and other species groups.
The quality of data on birds exceeded that regarding other vertebrates. Our results indicate that (a) EIA working groups of
independent experts were the most influential in determining the data to be used; (b) on average, proponents included data
more often than required by guidelines; and (c) in 30 to 40% of the EIAs, the participation of nongovernmental organizations
prompted use of data. Despite the key role of experts in data inclusion, the taxon rankings found in the EIAs showed little
deviation from those observed in studies on people’s preferences for species. Given the limited ranges of species considered,
it is doubtful that the EIAs examined effectively contributed to conserving animal species diversity.
Edo Knegtering produced this work in his personal capacity 相似文献
822.
/ In 1991 and 1992, temperature, salinity, and fluorescence were measured by automatic continuous registration using instrumentation on a ferry crossing the southern North Sea daily along a transect between Zeebrugge, Belgium, and Hull, United Kingdom. The temperature ranged between 4 and 21 degrees C off the Belgian coast and between 6 and 17 degrees C in the middle of the transect. Salinity varied between 34 and 35.5 PSU in the offshore part of the transect, but showed much larger variation along the Belgian and UK estuarine coasts. Fluorescence, which was used as a measure of phytoplankton biomass, was highest at the continental coast and lowest near the English coast. Spring blooms of phytoplankton were found along the continental coast and in the channel-influenced water; in 1991 the blooms were denser than in 1992. Some summer blooms were also recorded. Water masses could be distinguished on the basis of salinity and fluorescence patterns. The general patterns in the data are compared with the literature and discussed in relation to river discharge, light penetration, and wind speed and direction. Finally, the value of automatic and frequent measurements of fluorescence for monitoring phytoplankton is compared with less frequent observations at selected stations. It is concluded that accurate information about phytoplankton biomass can only be established from the high-frequency data. KEY WORDS: Monitoring; Sampling; North Sea; Ferry; Fluorescence; Salinity; Temperature 相似文献
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PaulR. Wolf Terrence J. Keating 《Journal of the American Water Resources Association》1973,9(2):312-319
ABSTRACT Necessary input parameters for studying mixing zone characteristics of thermal plumes are horizontal surface and subsurface water velocities. Using time lapse aerial photography and analytical photogrammetric techniques, movements of drogues in an effluent plume were traced. From these traces accurate velocity vectors were obtained. Photographic coordinates of drogue images were measured using a glass scale. From the photo coordinates and the results of a ground control survey, an analytical solution was made for positions of drogues in the water at known intervals of time. Drogue positions were mapped for selected exposures thereby providing a visual display of velocity vectors in the study area. A rigorous error analysis was performed to determine the validity of the computed results. 相似文献
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Hans Kuhn 《Die Naturwissenschaften》1967,54(15-16):429-435
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