[Influence of landscape characteristics on non-point source pollutant output in Taihu upper-river basin].
Based on the observed data in monitored drainage areas and GIS spatial analysis tools, watershed basic database of Taihu upper-river basin was built. Using the methods of multiple stepwise regression and redundancy analysis, the influence of landscape characteristics on non-point source pollutant output at the outlets of watersheds and their relative influence intensity were analyzed. The dominant landscape characteristics influencing non-point source pollutant output in Taihu upper-river basin and sub-watersheds were also illustrated. The results show that there are strong correlations between non-point source pollution and landscape characteristics, in which land use makes the most remarkable effect, followed by soil characteristics and average slope and watershed area in turn. Residential land proportion, farmland proportion and average terrain slope with higher importance and significance level, are the dominant landscape characteristics variables affecting non-point source pollutant output of watersheds. 59.5% of water quality information and 98.6% of relation information between landscape characteristics and water quality can be explained by these three variables. Furthermore, the contribution rates of these three landscape characteristics to non-point source pollutant output in each sub-watershed are different.
Li
Yan
Y
Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China. yanli@niglas.ac.cn
Li
Heng-Peng
HP
D002681:China; D004784:Environmental Monitoring; D005618:Fresh Water / Q000032:analysis*; D012044:Regression Analysis; D012989:Soil Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D012989:Soil Pollutants; D014874:Water Pollutants, Chemical