Journal of Geographical Sciences ›› 2008, Vol. 18 ›› Issue (3): 353-362.doi: 10.1007/s11442-008-0353-5

• Climate and Environmental Change • Previous Articles     Next Articles

Heavy metal pollution of soils and vegetables in the midstream and downstream of the Xiangjiang River, Hunan Province

WANG Lixia1,3, GUO Zhaohui2, XIAO Xiyuan1,2, CHEN Tongbin1, LIAO Xiaoyong1, SONG Jie2, WU Bin1,3   

  1. 1. Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China|
    2. Institute of Environmental Engineering, School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China
    3. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2008-03-20 Revised:2008-05-10 Online:2008-09-25 Published:2010-09-18
  • Supported by:

    National Natural Science Foundation of China, No.20507022

Abstract:

A total of 219 agricultural soil and 48 vegetable samples were collected from the midstream and downstream of the Xiangjiang River (the Hengyang–Changsha section) in Hunan Province. The accumulation characteristics, spatial distribution and potential risk of heavy metals in the agricultural soils and vegetables were depicted. There are higher accu-mulations of heavy metals such as As, Cd, Cu, Ni, Pb and Zn in agricultural soils, and the contents of Cd (2.44 mg kg-1), Pb (65.00 mg kg-1) and Zn (144.13 mg kg-1) are 7.97, 3.69 and 1.63 times the corresponding background contents in soils of Hunan Province, respectively. 13.2% of As, 68.5% of Cd, 2.7% of Cu, 2.7% of Ni, 8.7% of Pb and 15.1% of Zn in soil sam-ples from the investigated sites exceeded the maximum allowable heavy metal contents in the China Environmental Quality Standard for Soils (GB15618-1995, Grade II). The pollution characteristics of multi-metals in soils are mainly due to Cd. The contents of As, Cd, Cu, Pb and Zn in vegetable soils are significantly higher than the contents in paddy soils. 95.8%, 68.8%, 10.4% and 95.8% of vegetable samples exceeded the Maximum Levels of Contami-nants in Foods (GB2762-2005) for As, Cd, Ni and Pb concentrations, respectively. There are significantly positive correlations between the concentrations of Cd, Pb and Zn in vegetables and the concentrations in the corresponding vegetable soils (p<0.01). It is very necessary to focus on the potential risk of heavy metals for food safety and human health in agricultural soils and vegetables in the midstream and downstream of the Xiangjiang River, Hunan Province of China.

Key words: Xiangjiang River, agricultural soil, vegetable, heavy metal, pollution