نتایج جستجو برای: roach
تعداد نتایج: 763 فیلتر نتایج به سال:
Flow-through toxicity tests were conducted on common freshwater fishes: rainbow trout (Oncorhynchus mykiss), three-spined stickleback (Gasterosteus aculeatus), roach (Rutilus rutilus), perch (Perca fluviatilis) and dace (Leuciscus leuciscus), to estimate their sensitivity to acute toxicity of nickel. The 96-hour median lethal concentration (96-hour LC50) values obtained from the tests ranged fr...
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In the present study, classification trees (CTs-J48 algorithm) were used to study the occurrence of roach in rivers in Flanders (Belgium). The presence/absence of roach was modelled based on a set of river characteristics. The predictive performance of the CTs models was assessed based on the percentage of Correctly Classified Instances (CCI) and Cohen's kappa statistics. To find the best model...
The content of heavy metals in fish different ecological groups the conditions Argazinsky reservoir (Russia) has been studied, its safety when used as a product nutrition was given. material study “local” (bream, pike, perch, roach, whitefish) caught by fishermen. determined atomic absorption method. Compared to muscular tissue, bone tissue found accumulate more manganese, zinc, cadmium, lead, ...
Surveys of U.K. rivers have shown a high incidence of sexual disruption in populations of wild roach (Rutilus rutilus) living downstream from wastewater treatment works (WwTW), and the degree of intersex (gonads containing both male and female structural characteristics) has been correlated with the concentration of effluent in those rivers. In this study, we investigated feminized responses to...
artificial fertilizers and mainly organophosphate herbicide are used by farmers to enhance their crop and control pests. in order to investigate the effects of pretilachlore, fingerlings of caspian roach were exposed to a range of concentrations of toxin close to those of estuary for 96 h. due to movement of these fingerlings in a gradient of salinity from freshwater to brackishwater some physi...
the purpose of the present study was to determine the acute toxicity (lc 50 ) of hgcl 2 and cuso 4 in caspian roach ( rutilus caspicus ) and cuso 4 in caspian kutum ( rutilus kutum ). the caspian roach lc 50 values for hgcl 2 at 24, 48, 72, and 96-hrs of exposure, were 0.64, 0.61, 0.42, and 0.28 mg l -1 , respectively, and for cuso 4 were 11.55, 5.08, 2.49, and 1.47 mg l -1 , respectively. the ...
Steroidal estrogens, originating principally from human excretion, are likely to play a major role in causing widespread endocrine disruption in wild populations of the roach (Rutilus rutilus), a common cyprinid fish, in rivers contaminated by treated sewage effluents. Given the extent of this problem, risk assessment models are needed to predict the location and severity of endocrine disruptio...
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