Zhuang Yanhua, Hong Song, Zhan F Benjamin, Zhang Liang
Key Laboratory of Environment and Disaster Monitoring and Evaluation of Hubei, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan, 430077, China.
School of Resource and Environmental Science, Wuhan University, Wuhan, 430079, China.
Environ Monit Assess. 2015 Nov;187(11):718. doi: 10.1007/s10661-015-4946-z. Epub 2015 Oct 29.
The influence factor analysis for non-point source (NPS) pollution is very important to taking effective water pollution control measures. In this study, the self-organizing map (SOM) and linear model analysis were used to analyze the relationships between total phosphorus (TP) loads and influencing factors, both qualitatively and quantitatively. The land-use type, topography, and vegetation coverage were the main factors influencing the export of TP loads in Tangxun watershed. Slope and normalized difference vegetation index (NDVI) were chosen as characteristic indices of topography and vegetation coverage, respectively. For the whole watershed, the high TP loads were mainly distributed in areas with high slope and low vegetation coverage for a specific land-use type. For different land types, the slope significantly influenced the export of TP loads in waste/bare land and forest/green land while NDVI influenced the export of TP loads in forest/green land and farmland. In terms of multi-factor analysis, the comprehensive influence of slope and NDVI on TP loads showed as waste/bare land>forest/green land>farmland>rural/urban construction land.
非点源（NPS）污染的影响因素分析对于采取有效的水污染控制措施非常重要。在本研究中，采用自组织映射（SOM）和线性模型分析方法，从定性和定量两个方面分析总磷（TP）负荷与影响因素之间的关系。土地利用类型、地形和植被覆盖是影响汤逊流域TP负荷输出的主要因素。分别选取坡度和归一化植被指数（NDVI）作为地形和植被覆盖的特征指标。对于整个流域，在特定土地利用类型下，高TP负荷主要分布在坡度大、植被覆盖低的区域。对于不同土地类型，坡度对荒地/裸地和林地/绿地中TP负荷的输出有显著影响，而NDVI对林地/绿地和农田中TP负荷的输出有影响。在多因素分析方面，坡度和NDVI对TP负荷的综合影响表现为荒地/裸地>林地/绿地>农田>农村/城市建设用地。
