摘要
在实验室模拟条件下初步研究了农药单甲脒从本身纯物质及土壤表面的挥发行为．实验表明，挥发通量的对数与温度的倒数呈线性关系；单甲脒从有机质含量低的土壤中挥发较其从有机质含量较高的土壤中挥发要快；在一定范围内，土壤中单甲脒的挥发通量随着土壤中农药的浓度增加、温度的上升和风速的增加而增加；土壤水分的增加最初促进单甲脒挥发，继续增加则可能使挥发减慢．
The volatilization of N′—(2,4 dimethylphenyl)—N—methyl_formamidine (DMA) from the surface of DMA pure substance and soil were initially measured in laboratory. The result shown that at the air flow of 3.33m/min, the vapor flux of DMA from the surface of pure DMA was 2.59,6.67 and 18.13 mg/(m 2·h), at 30,35 and 40℃,respectively. There was a linear relationship between the reciprocal of the temperature and the logarithm of the value for DMA vapor flux from the surface of DMA pure substance. Factors influencing the volatilization of DMA from soil were also investigated. Under the same condition, the volatilization of DMA from soil with low organic matter was generally greater than that from soil with high organic matter. In a limited extent, the vapor flux of DMA increased with the increase of DMA concentration in soils, the temperature or the air flow rate. The increase of water content in soil was able to raise the DMA volatilization at first, however, more water probably reduce the volatilization of DMA. Without water evaporation from soil at 25℃, total amount of DMA vaporized from sand loam soil during the first four days was measured as 0.28mg, which is 5.6% of all used pesticide.
出处
《环境科学学报》
CAS
CSCD
北大核心
1999年第2期194-199,共6页
Acta Scientiae Circumstantiae
基金
国家自然科学基金
关键词
单甲脒
农药
土壤
挥发
残留物质
N′—(2,4—dimethylphenyl)—N—methylformidine, pesticide, soil, volatiolization.
