Abstract:Degradation dynamics of fenvalerate in three soils was studied to explore effects of soil properties on degradation. Results show that the half-time of fenvalerate in the soils was 25.3,19.4,and 17.7 days,and the degradation rate constant 0.0274,0.0357,0.0392,respectively,demonstrating that fenvalerate degradated the fastest in huangni soil and the slowest in qingzi soil. Degradation of fenvalerate in soils seemed to be attributed to activities of microbes,as the degradation rate was lower in sterilized soil. The most important factors affecting its degradation rate in soil are organic matter content and pH1 Environmental factors also affect fenvalerate degradation rate. The half-time of fenvalerate decreased with rising temperature and moisture,while its degradation rate did with higher initial application rate of the pesticide.