Temporal and spatial evolution characteristics of water environment quality in Heze

The evolution of water environment is relatively complicated. The study of its characteristics is helpful to grasp the general direction of spatial and temporal evolution of water environment in Heze city, and to carry out water resources development and water environment protection more rationally. The comprehensive pollution index method for calculation, and the observed data are handled by Excel. In order to facilitate the analysis of the basin, Arcgis is utilized to map the watershed map. In addition, for the spatial evolution, surfer12 is used to analyze the spatial evolution characteristics the spatial evolution, and to draw the pictures of spatial evolution of chemical oxygen demand and water quality evolution. The study shows that: (1) In Heze, the quality of water environment has been improved year by year from 2006 to 2013. In 2014, the water environment has deteriorated. The content of volatile phenol has increased greatly, and the evolution trend of COD is close to the trend of the comprehensive pollution index. (2) In terms of Spatial state of water environment, the water quality of Zhuzhao New River and Wanfu River is poor, and Dongyu River water quality is better. Zhuzhao New River and Wanfu River water qualityis often worse than grade V or V, and Dongyu River water quality is mostly maintained in the grade Ⅳ. Through the analysis on the spatial revolution characteristics of water quality and chemical oxygen demand(COD),as a result, water quality is poor in the northern region,and the water quality in the southern region is better in Heze. Although the water quality has changed in recent years, the overall pattern is relatively stable.