Effect of Herbicide Residues on Microbial Processes in Cropland Pond or Impoundment Sediment

摘要

An assay system is described for examination of potential effects of herbicides on non-target sediment microorganisms. Sediments were obtained from a catfish aquaculture pond and an adjoining lake that are adjacent to croplands. Potted sediment and undisturbed sediment cores showed no corresponding difference in glucose mineralization, acetylene reduction, phosphatase and dehydrogenase activities, but did show a significant difference in methanogenesis. Diuron, paraquat, CuS0-4 and simazine could be characterized by their differential effect on the above activities after 1-wk in two different aquatic sediments. Chronic effects (4-8 wk) by these four herbicides, were not observed. The results support the concept that a battery of tests are required to profile and evaluate the effects of herbicides on sediment microbial communities.