Research On Water Quantity And Quality Changes In Shaying River Under The Control Of Multiple Sluices

There are many dams in the Huai River,water pollution incidents have also occurred in last century,most of them are related to the Shaying River.Shaying River is the largest tributary of the Huai River,with the development of economy,water resources are facing severe challenges:the exploitation and utilization of water resources is high,but efficiency of water using is low.Especially in the water shortage areas where ecological and environmental water is squeezed.The dries up of the river still exists;years of harnessing in the Huai river has got some good effect,but it is still serious.From an interannual aspect,the concentration of ammonia nitrogen(NH3-N and permanganate index(CODMn)in important sections decreased and the degree of dispersion during the year weakened in 2009-2013;NH3-N and CODMn began to decrease after the beginning of the flood season(June to September)and could reach Class III in Environmental Quality Standards for Surface Water,the valuese of NH3-N varied greatly through the year,concentrations in non-flood season were much higher than that in flood season,the distribution of CODMn was more even during the year.This is mainly related to application of nitrogen fertilizer and sewage from cultivated lands in crop growth season in spring,autumn,and winter.It is also related to the degradation of river stream in dry season,the operation of the dam would also affect the stream self-purification.The plenty of water flow in the main flood season in Shaying River,the flow in the dry season before the flood was less than that in other periods.Flows were highly consistent from upstream to downstream,which is mainly because of the sluices oprations.The results of Huai River method on the ecological flow analysis at provincial boundary of the Shaying River showed that largest satisfaction degree of the enviromental flow from June to September,while the habitat method had a low satisfactionfor it required the comparable largest ecological flow from Aprjl to May.The difference between the two methods is that the habitat method considers the fish spawning needs in April and May.In most of the cases from 2009 to 2013,the ecological water of the river could be satisfied,the shortage could be happen when the amount of available water is low and the water requirement is high.Baiguishan Reservoir has a great significance to ensure the improvement of water quality,water quality,and ecological environment in the river.The results of water resources analysis showed that the interannual variation of precipitation is large,precipitation also has a seasonal change,and the inflow is uneven.The inflow is able to meet the demand and it can release ecological water in most years except continuous dry years.The released discharge from the reservoir greatly improves the water quality and quality of the Shaying River,which increases the improvements with the increase of discharge flow.Industrial water consumption is related to industrial output,industrial structure,and recycling.The domestic water useage is related to the population,industrial,and living water consumption,which would increase but not significant in the future.Agricultural water consumption is related to grain yield,acreage,and precipitation,which will not have a significant increase or decrease trend in the future.The actual operating water level of the reservoir from 2002 to 2014 showed that the water resources utilization is inadequate.The water shortage would happen in dry years.The key to reservoir dispatch is the balance of water storage and release.A minimum water-abandoning model is established based on above discussion,the reservoirs should maintain the minimum ecological flow before the limited storage capacity is reached,and the abandoned water is released after the limited storage capacity is reached.The ecological water use at downstream and the water stroraged in the reservior can be garenteed by meas of joint opration of sluices,which will finally improve the water evironment in Shaying River and support the water quanlity-quantity-ecosystem regulation for Huai River.