Water Quality of River Wetlands in the Sanjiang Nature Reserve

The Sanjiang Nature Reserve plays an important role in conservation of environmental and natural resources,such as ecosystem and wild lives.There are 2 international rivers in the region;they are the Heilongjiang River and the Wusulijiang River.The Nongjiang River,the Yalu River and the Bielahong River are the first grade tributaries that flow into the Heilongjiang River,and there are more than 30 second and third tributaries distributing in the area.To the wetland,water is just like blood in the body and constitutes an abundance and integrated ecosystem.So water is the most sensitive factor in the wetland ecosystem,controlling and maintaining the construction and function of the wetland.The study region is located in the Heilongjiang River basin.The object is the water of main rivers of the area No.1 and the area No.2 in the study region.There were 14 sampling sites were chosen in the study region.In spring,summer and autumn in 2005,water samples were collected in the sites of area No.1 and No.2 respectively,and the concentration and changes of the total phosphorus(TP),chemical oxygen demand(COD),NO3—N,NO2—N and NH4—N were examined in the water.The distribution characteristics and the affect factors that influenced the water quality of river wetlands in the study region were study.The results showed that,in area No.1 and area No.2,the distribution characteristics of the water environment quality in the rivers were similar,and the pollutants concentrations in water and the purifying functions of the river wetlands were both fluctuant with season change.TP concentrations of the water in the area No.1 were more than those in the area No.2.The maximum of TP concentrations occurred in the site No.1 in the Nongjianghe River of the area No.1 in autumn was 2.483 mg/L.The maximum of COD concentrations happened in the site No.7 of the area No.1 in summer was 82.7 mg/L.The purifying capabilities of river wetlands in the area No.2 on nitrous and phosphoric pollutants were different in various seasons.In spring,the concentrations of TP and NO3—N in the water of the 2 areas were rising,while COD declined.In summer,organic pollution was serious,the river wetlands in 2 areas both contributed to purify TP and NO3—N,but COD concentration in the water raised.In autumn,the purifying functions of river wetlands in 2 areas were declined but still reacted,while the wetlands was incapable to purify NO3—N and COD in the water.The NO3—N in the water experienced an obvious accumulation process.The purification capacity of river wetlands in the area No.2 was more than that in the area No.1.