摘要
以西安护城河的东南角为分水岭,将其按流向分为A支(向西转向北)与B支(向北转向西).对15个采样点水体的物理指标、CODcr、NH3-N、TP、重金属等指标进行了测定分析.结果表明,A支由A1～A6,颜色由无色到深绿,味道由无味到臭,电导率值变化范围为286 ～1 139 μS/cm,CODcr变化范围37.57 ～ 770 mg/L,NH3-N变化范围0.38 ～ 4.54 mg/L,TP变化范围0.165 ～0.884 mg/L,且随着护城河河水的流向,理化参数有较规律的变化,说明了A支可能主要受到河床底泥、藻类植物、水面漂浮物等内源污染;B支由B1 ～ B6,理化参数变化无明显规律,但在B8处,CODCr、NH3-N、TP均达到整个护城河的最大值,说明B支可能除受到内源污染外,还受到城市雨水径流与部分市政污水等外源污染.依据地表水环境质量标准(GB 3838-2002),A1～ A2段属地表水V类水体水质标准,其他段属于劣Ⅴ类水体水质.此外,对Cu、Pb、Zn、As、Hg、Cd、Cr、Ni等元素的监测结果显示西安护城河上覆水受到重金属的污染相对较小.
Abstract
According to the flow of Xi' an moat, it is divided into two branches. There are 15 sampling points set along the two branches. Physical index of the 15 sampling points including C0DCr,NH3-N,TP, heavy metals and other indicators were measured and analyzed. The results showed that along the tributary A from sampling points Al to A6,the water color from colorless to dark green,the flavor from the tasteless to smelly, the conductivity varies from 286 μS/cm to 1 139 μS/cm, CODCr ranges from 37. 57～ 770 mg/L,NH3-N changes in the range of 0. 38～4. 54 mg/L, TP values between 0. 165 mg/L and 0. 884 mg/L. And with the river flow, these index compared to a regular variation, it indicates that Group A may be mainly affected by endogenous pollutants such as the riverbed sediment, algae and floating ma-terials. While along the B branch from sampling points Bl to B6,these parameters have no obvious varia-tion trend. But in the sampling point B8,indicators like C0DCr,NH3-N and TP have reached the maximum values of the 15 sampling points. It shows that the B branch may be polluted not only by endogenous pol-lutants , but also by exogenous pollutants including urban runoff and some municipal wastewater. The con-clusion is that from Al to A2, the surface water is classified Class V water quality based on GB 3838-2002. The other segment of the moat river surface water is classified Bad Class V water quality. In addi-tion , Cu, Pb, Zn, As, Hg, Cd, Cr, Ni and other elements of the monitoring results shows that the overlying water in Xi' an moat subject to heavy metal pollution is relatively light.
基金项目
陕西省自然科学基础研究计划(2012JM5006)
NETL
NSTL
维普
万方数据