Study on Relationship between Microbial Diversity and Organophosphate Pesticide Residues in Planting Base Soils of Shenyang

Abstract

In order to study the relationship between microbial diversity and organophosphate pesticide residues in planting base soils, six soil samples including three sandy soils and three cohesive soils were selected, from vegetable and crop base of Shenyang. Based on determining the level of pH, N, P, the organic matter and moisture contented in those soil samples, the physical and chemical properties of soil were confirmed. The pesticide residues in soil samples were analyzed by ultrasonic extraction-gas chromatographic. The results showed that the most frequently determined pesticide in soils was isofenphos-methyl, dimethoate and methyl parathion (100% of samples) followed by parathion (50%). The highest concentrations of pesticide residues in soils were determined for isofenphos-methyl (534.52µg/kg) in side 3#and isofenphos-methyl (255.81µg/kg) in side 1#. But phorate was not detected, in the soils from all sites. Organ phosphorus pesticides have a certain inhibitory effect on microorganism. Shannon index of fungal diversity was reduced with the increasing of total pesticide content in sandy soils. These suggested that pesticide pollution resulted in decreasing of functional diversity of the soil microbial community. Microorganisms in the sandy soil were more resistant to organ phosphorus pesticides, as compared with the sticky soil.