The Degradation Trends of Phenoxyacetic Acid Herbicides in Soils
土壤中苯氧羧酸类除草剂的降解动态

The degradation trends of MCPA,2,4 D and nitrofen in soils under the simulated conditions in the laboratory was performed.They were incubated in three kinds of soils with different contents of organic matter.Their contents in soils were determined at a period of time.It was discovered that their contents were diminished gradually with the time.Without thinking of the effect of different microbe in soils,the stability of three pesticides seems to have a relation with the contents of organic matter and the value of pH.Herbicides degraded more quickly in the soils with higher contents of organic matter than those with lower contents of organic matter.The half life value of MCPA,2,4 D and nitrofen in black soil was 28.6d,27.3d,71.5d and in red soil 223.6d,31.4d and 97.6d respectively.Phenixyacetic acid herbicides are more stable in the acid soils.