科研之友
微信
新浪微博
Facebook
分享链接
摘要
We divided a 26-year period into six five-year-plan periods in this paper: the "Sixth Five Year Plan" (1985, 6th fyp), "Seventh Five Year Plan" (1986-1990, 7th fyp), "Eighth Five year plan" (1991-1995, 8th fyp), "Ninth Five Year Plan" (1996-2000, 9th fyp), "Tenth Five Year Plan" (2000-2005, 10th fyp) and "Eleventh Five Year Plan" (2006-2010, 11th fyp). Pollution index (PI) and Nemerow's synthetical pollution indexes (P) were used to assess the farmland soil quality. The highest content of Cd, Ni and Hg appeared in the 6th fyp; Cu, Pb, Cr in the 11th fyp; Zn in the 8th fyp; and As in the 7th fyp. The spatial-temporal distribution of the pollution indices for the heavy metals in the farmland soil revealed that Cd, Zn and Hg contributed the most pollution. The higher pollution areas were mainly in the Minhang, Pudong and Jiading districts, which are the closest districts to urban areas. Relatively clean areas were found in Jinshan, Fenxiang and Chongming district, the districts farthest from urban areas. Overall, the P values showed that the pollution trend of the whole Shanghai area was gradually controlled after the 8th fyp. The reduced use of fertilizers, decreased the discharge of industrial waste water, and increasing the disposal rate of waste water and solid waste relieved the impact of agricultural and industrial activities on the temporal variation of farmland soil quality. However, the urbanization process significantly influenced the spatial distribution of the farmland soil quality, especially in districts near urban areas.
- 出版日期2013
- 单位华东师范大学
