化学农药在茶树上多种降解因子定量关系的研究

作者采用实验室模拟与田间试验相结合的方法,研究了光照、温度、水分和茶树生长等主要环境因子对氯氰菊酯、马拉硫磷在茶树上降解的影响及定量关系。结果表明,同种环境因子对不同类型农药在茶树上降解作用的差异很大。茶树新梢的生长稀释对田间残留期长的氯氰菊酯的降解起主导作用,可占田间总降解的60％;而挥发和热分解对残留期较短、蒸气压较高的马拉硫磷的降解起主导作用,在复季可占田间降解的50％。光解和水解对这两种农药在茶树上的降解也起着一定作用。此外,降雨、风和生物代谢等也不同程度地影响农药在茶树上的降解。

STUDIES ON THE QUANTITATIVE EVALUATION OF ENVIRONMENTAL FACTORS IN THE DEGRADATION OF PESTICIDE ON TEA PLANT

The role and quantitative evaluation of sunlight,temperature,rain-fall,growth dilution,and other main environmental factors in relationto the degradation of cypermethrin and malathion have been investigatedwith laboratory simulation combined with field experiment.Resultsshowed that the same environmental factor plays a highly variable rolein the degradation of different types of pesticide on tea plant,and thegrowth dilution and volatilization play the dominant role on the degrada-tion of cypermethrin and malathion respectively.Growth dilution takesup nearly 60% of the total field degradation of cypermethrin under fieldconditions,and volatilization does about 50% of the degradation of ma-lathion in summer condition.The quantitative evaluation of indivadualfactor in the total degradation of different pesticides on tea plant wascaculated and discussed.