Journal of Ecology and Rural Environment ›› 2019, Vol. 35 ›› Issue (11): 1445-1452.doi: 10.19741/j.issn.1673-4831.2018.0693

Previous Articles     Next Articles

Accumulation Characteristics and Evaluation of Heavy Metals in Suburban Farmland Soils of Tianjin

ZHANG You-wen1,2, HAN Jian-hua3, TU Qi2, YANG Yong-an4, XU Yan2, SHI Rong-guang2   

  1. 1. School of Land and Environment, Shenyang Agricultural University, Shenyang 110866, China;
    2. Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, China;
    3. Tianjin Agricultural Environmental Protection Management Station, Tianjin 300061, China;
    4. Tianjin Maize Elite Seed Farm, Tianjin 301508, China
  • Received:2018-10-30 Published:2019-11-19

Abstract: In order to obtain the pollution status of heavy metals in suburban farmland soils of Tianjin City, five heavy metal elements including As, Pb, Cd, Cr and Ni in 327 farmland soil samples from four suburban areas of Dongli, Xiqing, Jinnan and Beichen Districts were collected and analyzed. Results show that the average concentrations of As, Pb, Cd, Cr and Ni in soils were 10.01, 33.71, 0.32, 56.95 and 33.50 mg·kg-1, respectively, which were higher than their soil environmental background values of Tianjin except for Cr. Among the five heavy metals, Pb, Cd and As exceeded the "Soil Environmental Quality Risk Control Standard for Soil Contamination of Agricultural Land (GB 15618-2018)" with the exceeding rates of 3.06%, 14.07% and 0.31%, respectively. It suggested that contamination by Cd occurred in some of the farmland soils in Tianjin suburbs, and a small amount of farmland soils were contaminated by Pb and As, while the risk of soil contamination by other heavy metals was low. Evaluation of pollution degree of heavy metals in farmland soils by both single factor pollution index method and Nemerow comprehensive pollution index method show that the contamination of Cd in Tianjin suburban soils was at the alerting level. High Cd concentrations were mainly distributed in Dongli District, and in orchard soils. Other heavy metals were at safe levels. Overall, except for Cd, the risk of heavy metals pollution in surburban farmland soils of Tianjin City was low.

Key words: Tianjin suburb, farmland soil, heavy metal, accumulation characteristics

CLC Number: