Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China.
Institute of Qinling Mountains, Northwest University, Xi'an, 710127, China.
Int J Environ Res Public Health. 2020 Feb 7;17(3):1070. doi: 10.3390/ijerph17031070.
The sediment pollution caused by different metals has attracted a great deal of attention because of the toxicity, persistence, and bio-accumulation. This study focuses on heavy metals in the hyporheic sediment of the Weihe River, China. Contamination levels of metals were examined by using "geo-accumulation index, enrichment factor, and contamination factor" while ecological risk of metals were determined by "potential ecological risk and risk index." The pollutant accumulation of metals ranked as follows: "manganese (Mn) > chromium (Cr) > zinc (Zn) >copper (Cu) > nickel (Ni) > arsenic (As) > lead (Pb)". The geo-accumulation index identified arsenic as class 1 (uncontaminated to moderate contamination), whereas Cu, Cr, Ni, Zn, Pb, and Mn were classified as class 0 (uncontaminated). According to the enrichment factor, arsenic originated through anthropogenic activities and Cr, Ni, Cu, Zn, and Pb were mainly controlled by natural sources. The contamination factor elucidated that sediments were moderately polluted by (As, Cr, Cu, Zn, Mn, and Pb), whereas Ni slightly contaminated the sediments of the Weihe River. All metals posed a low ecological risk in the study area. The risk index revealed that contribution of arsenic (53.43 %) was higher than half of the total risk.
由于重金属的毒性、持久性和生物累积性，不同金属造成的底泥污染引起了广泛关注。本研究聚焦于中国渭河河底的底泥重金属。通过“地质累积指数、富集因子和污染因子”来检测金属的污染程度，通过“潜在生态风险和风险指数”来确定金属的生态风险。金属污染物的累积程度如下：“锰（Mn）>铬（Cr）>锌（Zn）>铜（Cu）>镍（Ni）>砷（As）>铅（Pb）”。地质累积指数将砷确定为 1 级（无污染到中度污染），而 Cu、Cr、Ni、Zn、Pb 和 Mn 被归类为 0 级（无污染）。根据富集因子，砷来源于人为活动，Cr、Ni、Cu、Zn、Pb 主要受自然来源控制。污染因子表明（As、Cr、Cu、Zn、Mn 和 Pb）对沉积物造成中度污染，而 Ni 则略微污染了渭河沉积物。研究区域内所有金属的生态风险均较低。风险指数显示，砷（53.43%）的贡献高于总风险的一半。
