Verification of the Effectiveness of BMP Techniques in a Long Time Period Using Trend Analysis

摘要

Best management practices (BMP) techniques which aim to preserve natural landscape features, reduce the impervious area, and mitigate non-point source pollution, have become popular in land development. This paper focuses on proving the effectiveness of BMP techniques via the water quality analysis. In this study an area, in South Florida, USA, was selected, which has 9 monitoring stations and a 30 years BMPs planting history. Water quality parameters are collected from 1980s to 2014, and the BMP facilities are deployed in the area from 1980s up to now. To catch the temporal variation characteristics of water quality measures, this study firstly compares two multivariable statistical water quality analysis methods--the exploratory factor analysis (EFA) water quality index (WQI) and the Canadian Council of Minister (CCME) water quality index (WQI). Comparison results show that EFA-WQI can accurately explain the trend and variation of long period water quality statistics. After this, the Mann-Kendall's test is used to detect water quality temporal change trends which indicate the impact of BMP techniques on the research areas. Analysis results show that the water quality index of most research area show a decrease trend over 30 years, and show some short-term decrease or increase trends during the 30 years. These phenomenon indicate that the application of BMP techniques has a long term benefit of gradually improve the environment.