Assessing Interactions of Multiple Agrichemicals by Using Bacterial Assemblages in a Wetland Mesocosm System

International Journal of Environmental Research and Public Health

Huey-Min Hwang²  Neisee McArthur²  Clifford Ochs¹ 

[1] Department of Biology, University of Mississippi, University, MS 38677, USA;Department of Biology, Jackson State University, Jackson, MS 39217, USA

关键词: Agrichemicals;    bacterial assemblages;    wetland;    mesocosm;   

DOI  :  10.3390/ijerph2005020019

来源: mdpi

【 摘 要 】

Agrichemicals may enter wetlands located adjacent to or downstream from agricultural fields. We investigated the individual and interactive effects of three agrichemicals [atrazine, chlorpyrifos, and monosodium acid methanearsonate (MSMA)] and methyl mercury on abundance and heterotrophic potential of wetland heterotrophic bacteria assemblages. We used a factorial experimental design, in which chemicals were introduced in all possible combinations to 66 500-liter mesocosms at the Biological Field Station of the University of Mississippi. Methyl mercury was added to bring the total mercury (HG) concentration to 0.4 mg/Kg wet weight at the sediment surface. Atrazine, chlorpyrifos, and MSMA were added at concentrations of 192, 51, and 219μg/L, respectively. Over 32 days of exposure, microbial heterotrophic activity was sensitive to only the interactive effect of HG*ATR*CPF in the sediments and only CPF in the water. Total bacterial numbers did not exhibit any significant treatment effects. Therefore, the effects of agrichemicals were reflected on cell-specific bacterial heterotrophic activity rather than bacterial population size.

【 授权许可】

CC BY   
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