College of Chemistry Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
Xinjiang Key Laboratory of Oasis Ecology, College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China; Ecological Postdoctoral Research Station, Xinjiang University, Urumqi 830046, China.
Ecotoxicol Environ Saf. 2016 Apr;126:94-101. doi: 10.1016/j.ecoenv.2015.12.025. Epub 2015 Dec 28.
The current study focused on the Bortala River - a typical inland river located in an oasis of arid area in northwestern China. The sediment and soil samples were collected from the river and drainage basin. Results showed that: (1) the particle size of the sand fraction of the sediments was 78-697 µm, accounting for 78.82% of the total samples; the average concentrations of eight heavy metals fell within the concentration ranges recommended by the Secondary National Standard of China, while the maximum concentrations of Pb, Cd, and Hg exceeded these standards; (2) results from multivariate statistical analysis indicated that Cu, Ni, As, and Zn originated primarily from natural geological background, while Cd, Pb, Hg and Cr in the sediments originated from human activities; (3) results of the enrichment factor analysis and the geo-accumulation index evaluation showed that Cd, Hg, and Pb were present in the surface sediments of the river at low or partial serious pollution levels, while Zn, Cr, As, Ni, and Cu existed at zero or low pollution levels; (4) calculation of the potential ecological hazards index showed that among the eight tested heavy metals, Cd, Pb, Hg, and Cr were the main potential ecological risk factors, with relative contributions of 25.43%, 22.23%, 21.16%, and 14.87%, respectively; (5) the spatial distribution of the enrichment factors (EF(S)), the Geo-accumulation index (I(geo)), and the potential ecological risk coefficient (E(r)(i)) for eight heavy metals showed that there was a greater accumulation of heavy metals Pb, Cd, and Hg in the sediments of the central and eastern parts of the river. Results of this research can be a reference for the heavy metals pollution prevention, the harmony development of the ecology protection and the economy development of the oases of inland river basin of arid regions of China, Central Asia and also other parts of the world.
本研究以中国西北地区干旱区绿洲内的典型内陆河流——博尔塔拉河为研究对象，采集了该河流及其流域的沉积物和土壤样品。结果表明：（1）沉积物砂粒部分的粒径为 78-697 µm，占总样品的 78.82%；八种重金属的平均浓度均处于中国《土壤环境质量 农用地土壤污染风险管控标准（试行）》二级标准范围内，而 Pb、Cd 和 Hg 的最大浓度超过了该标准；（2）多元统计分析结果表明，Cu、Ni、As 和 Zn 主要来源于自然地质背景，而沉积物中的 Cd、Pb、Hg 和 Cr 则来源于人类活动；（3）富集因子分析和地积累指数评价结果表明，Cd、Hg 和 Pb 存在于河流表层沉积物中，处于低或局部严重污染水平，而 Zn、Cr、As、Ni 和 Cu 则处于零或低污染水平；（4）潜在生态危害指数的计算表明，在所测的八种重金属中，Cd、Pb、Hg 和 Cr 是主要的潜在生态风险因子，相对贡献率分别为 25.43%、22.23%、21.16%和 14.87%；（5）八种重金属的富集因子（EF(S)）、地积累指数（I(geo)）和潜在生态风险系数（E(r)(i)）的空间分布表明，河流中部和东部的沉积物中 Pb、Cd 和 Hg 的积累程度更高。本研究结果可为中国干旱区内陆河流域、中亚及世界其他地区的重金属污染防治、生态保护与经济发展的和谐提供参考。
