Abstract:

Variation of  water quality in reservoir takes an important part in ecological security investigation and assessment of lakes and reservoirs, and also provides basis for ecological security monitoring and warning,ecological security assurance and development of the comprehensive treatment plan for lakes and reservoirs.Permanganate,ammonia nitrogen,and other parameters were chosen to be the main environmental factors,and the variation of water quality in Danjiangkou Reservoir was analyzed.The influencing factors including water quantity of the reservoir,input water from upstream and agricultural nonpoint source pollution as well as their relationship with the variation of water quality in Danjiangkou Reservoir were also explored.Besides,some suggestions were put forward about improving the water quality of the reservoir.In all,the water quality in Danjiangkou Reservoir has gradually become better and is changing in a positive trend through environmental protection and pollution control in recent years.The variation of water quality in Danjiangkou Reservoir is mainly related with nonpoint source pollution,and the monitoring system should be developed