西藏拉萨河流域巴嘎雪湿地水化学特征

以西藏拉萨河流域主要天然湿地之一的巴嘎雪湿地作为研究对象,对该湿地水体的pH值、水温、溶解氧(DO)、色度、浊度和15种金属元素的含量进行了分析检测.结果表明,巴嘎雪湿地水的pH、DO平均值分别为7.68、7.01mg/L;湿地水中15种金属元素含量均较低,汞、锡两种金属元素未能检出,其他13种金属元素的含量顺序为:Fe >Cr> V>Ni> Mn> As> Sb> Mo> Pb> Zn> Cu >Co> Cd,并均达到了国家《地表水环境质量标准》(GB3838-2002)Ⅰ类水质标准.通过比较湿地进水和出水水质的发现,巴嘎雪湿地对色度、浊度和部分金属元素的去除效果显著.对色度、浊度的去除率分别达到了51.73%、94.8%,对不同金属元素的去除效果不同,Cu、Pb、Zn、Mo、As、V的去除率分别为64.2%、36.9%、40.7%,28.2%、31.9%、67%.

Study on aquatic chemistry characteristics of Bagaxue wetland in Lhasa river basin,Tibet

Bagaxue wetland is one of an important natural wetland in the Lhasa River basin. We investigated the colority, turbidity, pH, temperature, dissolved oxygen (DO), and 15metal elements in water samples from Bagaxue wetland in the present study. The pH and DO value of water samples collected from Bagaxue wetland were 7.68and 7.01mg/L, respectively. The concentrations of metals were relatively low, Hg and Sn were not detected in all samples. The concentrations of rest 13metal elements followed the order of Fe >Cr >V >Ni >Mn >As >Sb >Mo> Pb >Zn >Cu >Co >Cd. The concentrations of metals in all water samples were under the criterion suggested by GB 3838-2002(The quality I of environmental quality standards for surface water). Compared with the influent of the water of wetland, the colority and turbidity were significantly decreased in effluent water of the wetland. The removal rates of colority and turbidity reached 51.73%、94.8%, respectively. Moreover, the removal rates of individual metal elements were different, the removal rates of V, Cu, Zn, Pb, As, and Mo were 67%, 64.2%, 40.7%, 36.9%, 31.9% and 28.2%, respectively.