Yanling County is the source of Mishui river,the surface water quality of the county city is evaluated and the trend of change is analyzed,to provide strong technical support for environmental management and river management.The results show that during the 13th Five Year Plan period in Yanling County,the main water quality indicators such as permanganate index,chemical oxygen demand,biochemical oxygen demand,ammonia nitrogen,and total phosphorus in the Taihe section showed a downward trend;the comprehensive water quality index shows a significant downward trend,indicating a significant improvement trend in the water quality of Taihe section over the past five years.The main water quality indicators of the Yangongtan section,such as permanganate index,chemical oxygen demand,ammonia nitrogen,and total phosphorus,all show a downward trend;the comprehensive water quality index shows an insignificant downward trend,indicating that the water quality of the Yangongtan section has shown an improvement trend over the past five years,but it is not significant.
NETL
NSTL
万方数据
