Purification effect of improved biological stabilization ponds on the polluted river in Lake Dianchi catchment

Abstract

对滇池流域大清河生物稳定塘系统中的水质净化效果进行了分析,同时对各塘中的浮游藻类种类组成、细胞密度和多样性进行了调查。结果表明,当污水流经预处理塘、好氧塘、水生植物塘、养殖塘的过程中,pH、DO、叶绿素a浓度呈逐渐上升趋势,TN、TP、NH₄⁺-N、BOD₅和COD浓度呈逐渐下降趋势,生物稳定塘系统对TN、TP、NH₄⁺-N、BOD₅和COD的去除率分别达29.29%,48.68%,33.68%,68.14%和71.25%。叶绿素a浓度和pH（r=0.955,P<0.05）、DO（r=0.992,P<0.01）显著正相关,而和TN（r=-0.936,P<0.05）、TP（r=-0.925,P<0.05）以及NH₄⁺-N（r=-0.927,P<0.05）等显著负相关。在塘系统中,共出现浮游藻类53种,藻类种类数和生物多样性呈增加趋势,总细胞密度呈下降趋势;塘系统中共出现6种藻类优势种,其中绿色微囊藻和惠氏微囊藻细胞密度呈现出逐渐下降的趋势,梅尼小环藻、啮蚀隐藻、美丽网球藻和球囊藻细胞密度呈现出逐渐上升的趋势。;Wastewater treatment effect, together with species composition, cell densities and diversity of phytoplankton, was inves-tigated in biological stabilization ponds of Daqing River. The results showed that pH, DO and chlorophyll-a concentration increasedgradually, and TN,TP, NH₄⁺-N, BOD₅ and COD decreased gradually when wastewater flew from the first pond to the last pond.The removal rates of TN, TP, NH₄⁺-N,BOD₅ and COD in biological stabilization ponds were 29. 29%, 48.68%, 33.68%,68.14% and 71.25%, respectively. Chlorophyll-a concentration was correlated significantly positively with pH(r=0. 955,P<0.05)and DO(r=0.992,P<0.01),but significantly negatively with'TN (r=-0.936, P<0.05),TP(r=-0.925,P<0.05)and NH₄⁺-N(r=-0.927,P<0.05).A total of 53 algal taxa including six dominant species were identified in biologicalstabilization ponds. Algal species and diversity increased gradually and total cell densities decreased gradually in the system ofponds. The cell density of Microcystis viridis and Microcystis wesenbergii decreased gradually, and that of Cyclotella meneghiniana,Cryptomoaas erosa, Dictyosphaeriam palchellura and Sphaerocystis schroeteri increased gradually.