Study On The Characteristics Of Residue Of Avermectin Analog Simulated Farmland For Water And Soil

This paper aims at studying for avermectin residue feature in water and soil in the form of rainfall through the farmland platform built by ourselves and determines avermectin in this platform whereabouts, analyzing its residue feature and transferring rule in plants, soil and water in the condition of nutural rainfall. This thesis applied insecticide avermectin pesticide to land planted cabbage in different rainfall patterns and different amounts of pesticide, doing research on its residue concentration, residual concentration variation and influencing factors in the water and soil, providing a theoretical basis and guidance for the pollution and prevention of avermectin in water and soil. In this paper, the whole experiment process was made by building simulations on independent farmland experimental platform.The following conclusions were drawn:(1) According to a constant amount of avermectin standard, three different rainfall conditions were investigated. The signs of residual avermectin was only detected under the condition of heavy rain in surface water. Under natural conditions, the pollution on surrounding farmland surface in moderate and light rainfall intensity water was smaller compared to the condition of heavy rain by using the standard amount of pesticide; In the middle ground water samples,the concentration of avermectin in the heavy rain water samples was lower than that in the middle rain water samples, decreasing more faster along with time.Experimental results indicate that; with the much more rainfalls in heavy rain, stronger impact on the avermectin compared with the middle rain and greater dilution effect, the concentration of avermectin in the middle ground water was lower, indicating that conditions of heavy rain caused less organic residue in the middle of groundwater compared to moderate rain according to the constant standard amount of avermectin.(2) On the condition of moderate rain, the amount of avermectin would cause organic pollution to the surface water when applying avermectin more than the 3/4 amount of standard, maybe washed by rainfalls into the surface water. While maintaining a constant rainfall, Avermectin residual pesticide concentrations in water with increasing amount of the increase, and the residual concentration in middle groundwater is greater than the surface water,but overall concentration in water samples is small.(3) Under the condition of three kinds of rainfall and three kinds of pesticides in the experiment period,Concentration of abamectin in surface water and middle water are low, and the bottom of the groundwater has been collected water samples were not detected in the remaining sign of abamectin.Description The experiment Avermectin pesticide sprayed into the soil and in the case of rain washed, does not into the bottom groundwater samples in this experiment, or the amount of Avermectin enter the body of water is too small beyond HPLC-UV detection after the limit and thus can not be detected;NOTE When using the new soil, increase the concentration of Avermectin cast has not yet reached the saturation limit soil adsorption capacity, resulting in a lot of rain can not be soil erosion or Avermectin down into the water.(4) Keep standard pesticide dosage, Abamectin in the concentration of the residues in soil mainly depends on the adsorption capacity of the soil, but the downward migration of abamectin in soil depends on the amount of the rainfall;Within the soil surface, is inversely proportional to the amount of the residual concentration of Avermectin and rainfall,in the soil surface to the middle range, Avermectin downward migration of proportional to;From this, it is found that rainfall is bigger, detected in the surface soil of Avermectin Residue concentration is low, rainfall is bigger, the distribution of Abamectin in soil down more, from the side reflect rainfall of Abamectin in soil residue removal effect.(5) Under the condition of constant moderate rain, concentration of abamectin residues in surface and middle soil increased with the applied dosage of abamectin, but the extent and amount of the increase is not proportional to the degree of increase, it may be followed by soil microbial decomposition of Avermectin and Avermectin action related to the presence of its own half-life.