Study on the Distribution Accumulation and Critical Level of Lead in Soil and Rice Along Road Sides
公路边土壤和水稻中铅的分布、累积及临界含量

he soil and rice samples were collected simultaneously at the sites of 5,10,50,100 and 200 meters away from road,respectively. The analysis results of samples collected along two roads demonstrated that the pollution of lead from automobile exhaust gas was within a range of about 50m along the roads. The soil characteristics had a significant effect on the distribution and accumulation of lead in soil and rice. The accumulation amount of lead in light loam was less than that in heavy loam,but the lead content of brown rice was more than that in heavy one. Correlation between the lead content of soil and that of brown rice bud been shown in light loam. Based on it,the critical level of soil along road side had been discussed. The predicted value was 58mg/kg,much less than that of pot experiments and the area irrigated with waste water.