~(14)C-氟乐灵在土壤中的迁移和降解

在实验室条件下,用放射性同位素示踪技术研究了~(14)C-氟乐灵(Trifluralin)在土壤中的吸附、迁移和降解。结果表明:氟乐灵在土壤中的吸附性很强,在不同土壤中的吸附率为73.89％～90.66％。土壤有机质含重对吸附有重要影响。氟乐灵在有机质丰富、粘粒含量较高的草甸黑土中淋溶很低,而在砂土中淋溶较高,易向下迁移。在厌氧条件的土壤中,氟乐灵降解较快,30天在土壤提取态中有60.2％～64.2％降解,610天有90.0％～94.7％降解,主要降解产物为R_f值等于0.06,0.15和0.42的化合物。

MOBILITY AND DEGRADATION OF ~(14)C-TRIFLURALIN IN SOIL

Under laboratory condition,the adsorption,mobility and degradation of 14C-trifluralin in soil were studied by using radioactive isotopic tracer.The results show that the adsorption of triflu-ralin in soil is quite strong.The rates of adsorption in soil are 73.89%~90.,66%.The adsorption is significantly affected by the organic matter content of soil.It leaches rather low in Grassy-marshland black soil containing plentiful organic matter and higher clay content,but quite higher in sand,and is more easily to move down.Under anaerobic condition,degradation of trifluralin in soil is faster.It is degradateds by 60.2%~60.4% in soil extractive state within 30 days,and by 90.0%~94.7% with in 60 days.Its main metabolites are the compounds with Rf 0.06,0.15 and 0.42 respectively.