Zhang Hua-Jun, Chen Xiu-Kang, Han Bo-Ping, Luo Yong, Yang Hao-Wen, Zeng Yan, Chen Jing-An
Institute of Hydrobiology, Jinan University, Guangzhou 510632, China.
Huan Jing Ke Xue. 2012 Apr;33(4):1167-75.
Core sediments were collected from the riverine, transition and lacustrine zones of Hedi Reservoir in southern China to investigate the spatial distributions of nutrients and heavy metals and assess the potential ecological risk of heavy metals. The total nitrogen (TN) contents of the sediments at three sampling sites are between 2.314-2.427 mg x g(-1), while total phosphorus (TP) contents range from 0.591 mg x g(-1) to 0.760 mg x g(-1), TN contents of the surface sediments increase from the riverine zone to the lacustrine zone, but the TP content in the transition zone is higher than that in the other two sites (riverine zone and lacustrine zone). The mean contents of heavy metals are: 31.094, 46.85, 75.615, 385.739, 0.624 and 0.171 mg x kg(-1) respectively, except Cr, the contents of heavy metals in sediment of lacustrine zone are higher than the sediment of transition zone. In all core sediments, the contents of nutrients and heavy metals decrease from the surface to the bottom of core sediments. Inorganic phosphorus (IP) is the dominant fraction of phosphorus in the sediment and the NaOH-P is the main forms of inorganic phosphorus. The potential ecological risk assessed by using of the highest environmental background values before industrialization as the reference indicates that each single heavy metal only causes slightly pollution, but two heavy metals (Cd and Hg) cause heavy pollution based on the soil environmental background values of Guangdong province. In spite of the slight difference between two kinds of risk assessment, all demonstrated that Cd and Hg resulted in more serious pollution than the other metals and these two metals contributed most to the RI values.
在中国南方鹤地水库的河流、过渡和湖泊区域采集了岩芯沉积物，以研究养分和重金属的空间分布，并评估重金属的潜在生态风险。三个采样点沉积物中的总氮（TN）含量在2.314 - 2.427 mg x g(-1)之间，而总磷（TP）含量在0.591 mg x g(-1)至0.760 mg x g(-1)之间，表层沉积物的TN含量从河流区域向湖泊区域增加，但过渡区域的TP含量高于其他两个区域（河流区域和湖泊区域）。重金属的平均含量分别为：31.094、46.85、75.615、385.739、0.624和0.171 mg x kg(-1)，除铬外，湖泊区域沉积物中重金属的含量高于过渡区域的沉积物。在所有岩芯沉积物中，养分和重金属的含量从岩芯沉积物的表层到底层逐渐降低。无机磷（IP）是沉积物中磷的主要组分，而NaOH-P是无机磷的主要形态。以工业化前的最高环境背景值为参考进行的潜在生态风险评估表明，单一重金属仅造成轻微污染，但基于广东省土壤环境背景值，两种重金属（镉和汞）造成重度污染。尽管两种风险评估之间存在细微差异，但均表明镉和汞造成的污染比其他金属更严重，这两种金属对风险指数（RI）值的贡献最大。
