Spatial and temporal variation characteristics of water quality and its influencing factors in Pihe River
To comprehensively reveal water quality pollution and the spatiotemporal variation characteristics of the Pihe River Basin in recent years,the water quality index(WQI)method was adopted to evaluate the river water quality based on monitoring data of pH,dissolved oxygen(DO),chemical oxygen demand(COD),5-day biochemical oxygen demand(BOD5),ammonia nitrogen(NH3-N),total nitrogen(TN),and total phosphorus(TP)from the mainstream of the Pihe River from2018 to2022.Additionally,correlation analysis was considered to identify key water quality indicators influencing water quality.The results were as follows:① The mainstream of the Pihe River has generally favorable water quality,with WQI averaging at(75.94±7.47),ranking in the"good"range.However,during non-flood seasons,the concentration of NH3-N ranged from 0.020～1.480 mg/L,signifying a relatively high load.②The spatial distribution of water quality ranked as follows:Hengpaitou>Dadiangang>Yaogangzui>Xin'an Ferry.③At the time level,the water quality of mainstream during the flood season(June to September)was markedly superior to that during the non-flood season(January to May and October to December).④ The correlation analysis showed that the water was mainly polluted by NH3-N,TN,and COD in the study area.In the Hengpaitou-Yaogangzui section and Xin'an Ferry-Dadiangang section with arable land as a major land use type,the water was mainly affected by COD,TN,and NH3-N generated from fertilizer application and livestock farming.In the Yaogangzui-Xin'an Ferry section,the water quality was severely impacted by the direct discharge of urban domestic sewage and effluent from sewage treatment plants,causing serious NH3-N pollution.During the flood season,water pollution gradually alleviates as concentrated rainfalls happen.From the per-spective of protecting the ecological environment of the Pihe River,this study proposed to boost the self-purification capacity of the watershed,strengthen the prevention of agricultural non-point source pollution,and improve the intercepting and treating sew-age systems.
water qualityWQIvariation trendinfluencing factorsPihe River
国家科技期刊平台
NSTL
万方数据
