Sources of streams
نویسندگان
چکیده
منابع مشابه
Vulnerability of streams to legacy nitrate sources.
The influence of hydrogeologic setting on the susceptibility of streams to legacy nitrate was examined at seven study sites having a wide range of base flow index (BFI) values. BFI is the ratio of base flow to total streamflow volume. The portion of annual stream nitrate loads from base flow was strongly correlated with BFI. Furthermore, dissolved oxygen concentrations in streambed pore water w...
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In an agricultural catchment area in Germany we analyzed water samples from five entry routes for 2 insecticides. 5 fungicides and 13 herbicides. The sewage plant outlet and the emergency overflow of a sewage sewer contained only herbicides. In each farmyard runoff we found on average 24 g pesticides during application period, presumably caused by cleaning the spraying equipment. In comparison,...
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1. Our objective was to investigate the associations between benthic macroinvertebrate communities and environmental factors described at three spatial scales: local, reach and catchment. Differences in these associations, because of local topography, were determined by categorising sites into those having a large or small ‘reach contributing area’ (RCA), which is the lateral area of land contr...
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ژورنال
عنوان ژورنال: Nature
سال: 1974
ISSN: 0028-0836,1476-4687
DOI: 10.1038/252136a0