Analysis of Evolution of Water Quality and Quantity in Yichang River Basin
The evolution rules of precipitation,runoff and water quality indexes in Yichang River Basin can pro-vide data support for water resources development and utilization,water environment protection and water ecolo-gy improvement.The linear trend regression test is used to study the change trend,and the ordered cluster analy-sis is used to analyze the mutation.The space-time changes of water quality index is analyzed and the water quali-ty is evaluated.Based on Pearson correlation analysis and double cumulative curve method,the causes of water quality changes in Yichang River Basin were studied.The results showed that the trend of precipitation,runoff,dissolved oxygen,permanganate index,ammonia nitrogen and fecal coliform was not obvious.In general,the water quality of the downstream section is better than that of the upstream section.From the perspective of sea-sonal changes,the water quality in winter is mostly qualified and better.From the perspective of annual changes,water quality changes fluctuate;the effect of runoff on dissolved oxygen and ammonia nitrogen was greater than that of precipitation and water temperature.The effect of water temperature on permanganate index and fecal coliform was greater than that of precipitation and runoff.The change of water quality indicators is affected by natural factors and human activities.
water quality and quantity changelinear trend regression testordered cluster analysisPearson corre-lation analysis
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NSTL
万方数据
