彭山岷江大桥国控监测断面水质类别变化分析

彭山岷江大桥国控断面，位于岷江干流，2010年、2011年和2012年，其水质类别分别为IV类、劣V类和劣V类，主要污染物为氨氮和总磷。本文依据其上游府河中黄龙溪断面和南河中董坝子断面水质的例行监测数据来综合分析岷江大桥水质类别变化情况。分别从评价方法、浓度、流量和通量等几方面加以阐述，结果表明，2010—2012年度，岷江大桥氨氮浓度主要受黄龙溪断面水质的影响，岷江大桥总磷的变化受到黄龙溪和董坝子水质的共同作用。

Analysis on the Water Quality Variation of the State-controlled Sections of Pengshan Minjiang River Bridge

The state-controlled sections of Pengshan Minjiang River Bridge locates at the main stream of Minjiang River. The average water quality of these sections were in the control of Standard Grade IV, worse than Standard Grade V and worse than Standard Grade V in 2010, 2011 and 2012 respectively. The key pollutants were ammonia nitrogen and total phosphorus. Based on the routine water quality monitoring data of these sections, this paper analyzed the water quality variation of Minjiang River Bridge sections synthetically, which was elaborated from the aspects of assmssment method, concentration and flux. The results showed that in 2010 - 2012, the concentration of ammonia nitrogen was mainly affected by the water quality of Huanglongxi section, and the total phosphorus variationwas affected by the water quality of both Huanglongxi section and Dongbazi section.