Branchial mechanisms of acclimation to metals in freshwater fish

摘要: In most aquatic habitats the concentrations of trace metals are below threshold for detectable effects upon fish species. Threshold levels range from 1000 μg 1-1 depending toxicity metal (Spry et al, 1981). However, through a variety human activities, such as combustion fossil fuels, pulp and paper production, cement extractive metallurgy, have increased in ecosystems number industrialized areas world (Stumm Morgan, Metals increase either directly, result atmospheric deposition waste water discharge runoff (e.g. Pb, Hg, Cd, Cu, Zn), or indirectly, solubilization mobilization sediments owing to acidification Al Fe). While both marine freshwater threatened, soft fresh waters that poorly buffered, (i.e. low Ca(HCO3)2) particularly sensitive because they only prone acidification.