Application of multivariate statistical analysis to evaluate the effects of natural treatment system on water quality improvement

摘要

In recent years,many natural treatment systems in Taiwan have been built for the purposes of wastewater treatment,river water purification,and ecology conservation.To evaluate the effectiveness of natural treatment systems on water purification,frequent water quality monitoring is needed.In this study,the multivariate statistical analysis was applied to evaluate the contaminant removal efficiency at a constructed wetland,and the time series method was then used to predict the trend of the indicative pollutant concentration in the wetland.In this study,a constructed wetland locates in the Kaoping River Basin was used as the study site.The statistical software SPSS was used to perform the multivariate statistical analysis to evaluate water quality characteristics and effectiveness of water purification.Results from this study show that the removal efficiencies were 98％ for the Total Coliforms (TC),55％ for Biochemical Oxygen Demand (BOD),53％ for Chemical Oxygen Demand (COD),55％ for ammonia nitrogen (NH3-N),and 39％ for Total Nitrogen (TN).Results from the factor analysis show that 17 waterquality items of the study site could obtain four to six principal components,including nitrate nutrition factor,phosphorus nutrition factor,eutrophication factor,organic factor,and environmental background factor,the major influencing components were nutrition factor and eutrophication factor.