Metal impacts on microbial biomass in the anoxic sediments of a contaminated lake

摘要: [1] Little is known about the long-term impacts of metal contamination on microbiota anoxic lake sediments. In this study, we examined microbial biomass and metals (arsenic, cadmium, chromium, copper, iron, lead, manganese, zinc) in sediments Lake DePue, a backwater located near former zinc smelter. Sediment core samples were using two independent measures for (total microscopic counts total phospholipid phosphate concentrations) various fractions each (pore water extracts, sequential extractions, extracts all studied speciation by X-ray absorption fine structure). Zinc concentrations up to 1000 times higher than reported adjacent Illinois River ranged from 21,400 mg/kg source 1,680 river. However, solid not well correlated with pore good predictors concentrations. Instead, biomass, which varied among sites as much 2 times, was inversely arsenic established multiple linear regression. Monitoring other parameters naturally influence (e.g., organic carbon concentrations, nitrogen pH, sediment texture, macrophytes) revealed no differences that could explain observed trends. This study provides strong support control abundance contaminated freshwater