MIREADE Kurban1, BALATI Maihemuti2,3,4, ISMAYILAnwar2，RUKEYA Sawut2,4, NIJAT Kasim2,4, SHENG YongCai2
（1．College of Resources and Environment, China agricultural University, Beijing 100193, China ；
2. College of Resources and Environmental Science, Xinjiang University, Urumqi 830046, China;
3. Key Laboratory of Xinjiang General Institutions of Higher Learning for Smart City and Environment Modeling, Xinjiang University, Urumqi 830046, China;
4. Key Laboratory of Oasis Ecology Xinjiang University, Urumqi 830046, China)
Abstract: The objectives of this study were to systematically investigate the pollution status of heavy metals in soil, identify possible pollution sources and determine the potential ecological risk of heavy metals in the Anningqu vegetable base in Urumqi. Twenty-six soil samples and seven water samples were collected from different sites in the Anningqu vegetable base, and their contents of six heavy metals (Hg、As、Cr、Cd、Pb and Zn) were determined. The obtained data were analyzed statistically by methods of geo-accumulation index, pollution load index and potential ecological risk assessment and the potential major pollution sources were determined by the principal component analysis method. The results indicated: 1) The mean concentration of Cd in soil samples was 2.69 times higher than its National Second-grade Standard, the mean concentrations of Hg, Cr and Zn were 5.74, 1.74 and 1.52 times, respectively, higher than their soil background values in Xinjiang, and the mean concentrations of As and Pb were lower than their corresponding background values; the average concentration of Cr in irrigation water samples was 4.51 times higher than its national irrigation water standard. (2) The average Igeo values of 6 heavy metals in soil followed a trend of Cd＞Hg＞Cr＞Zn＞As＞Pb, and indicated that the pollution status of Cd was moderate to heavy, the pollution status of Hg was moderate, the pollution status of Cr was slight and the pollution status of other three metals was none. The PLIzone value of the study area was 1.90, indicating a moderate pollution, in which Cd contributed 56% the most, Hg contributed 22% the second. The average RI value of soil was 673.1, indicated a serious potential ecological risk. (3) Pb, Cr and Zn contents in soil of the vegetable base were mainly controlled by human activities, and As and Cd contents in soil of the vegetable base were mainly affected by complex pollution sources. The pollution of Cd and Hg should be concerned in agricultural production processes since they are major elements of causing ecological risks.
Key Words: vegetable base; heavy metal; Irrigation water; ecological risk assessment
EARTH AND ENVIRONMENT Vol.47, No.4, Tot No.330, 2019, Page 485-494