摘要 地表水水质评价对掌握区域水环境优劣具有重要意义。利用云南省昭通市境内22个水质监测站点2011~2016年水质监测数据,在对各站点历年水质进行评价的基础上,采用Mann-Kendall趋势检验法对水质变化趋势进行分析。结果表明:(1)昭通市总体水质较好,符合地表水Ⅰ~Ⅲ类水质标准的河长占总河长的90.8%。(2)从时间分布看,非汛期水质略好于汛期。(3)水质变化趋势上看,91.07%的站点无显著趋势,3.57%的站点部分监测指标有显著上升趋势,5.36%的站点部分监测指标有显著下降趋势;存在显著变化趋势的水质分析项目主要为氨氮与总磷,各站的高锰酸盐指数与五日生化需氧量变化趋势均不显著。(4)虽然昭通市各站点地表水水质在2011~2016年间变化趋势不显著,但有些项目指标仍呈现出一定的上升趋势,这说明全市地表水水质有变差的趋势,须采取水资源保护措施,改善地表水水质。 The evaluation of surface water quality is of great significance to grasp the state quo of regional water environment.In this paper,on the basis of evaluating the water quality of each site over the years,water quality data from 22 water quality monitoring stations in Zhaotong City,Yunnan Province from 2011 to 2016 was used to analyze water quality trends by Mann-Kendall trend test.The results showed that:(1)the general water quality of Zhaotong was good,90.8%of total river length met the water quality standards of class I to III.(2)In terms of temporal distribution,water quality in non-flood season was slightly better than that in flood season.(3)In terms of trend variation,91.07%of the stations showed no significant trend,some indexes obtained from 3.57%stations had a significant upward trend,some indexes obtained from 5.36%stations showed a significant decline trend.The main water quality analysis items that had significant trend were ammonia nitrogen and total phosphorus.The trend of permanganate index and 5-day biochemical oxygen demand at all stations was not significant.(4)Although the surface water quality of the stations in Zhaotong City did not change significantly between 2011 and 2016,the indexes still showed a certain upward trend.This means that the surface water quality had a trend of deterioration.Water conservation measures are needed to improve the surface water quality.
机构地区 昭通市水利水电勘测设计研究院
出处 《水利水电快报》 2021年第4期75-78,82,共5页 Express Water Resources & Hydropower Information
关键词 水质评价 地表水 水质监测 MANN-KENDALL 昭通市 water quality evaluation surface water water quality monitoring Mann-Kendall Zhaotong City
