Resources Science ›› 2019, Vol. 41 ›› Issue (2): 405-413.doi: 10.18402/resci.2019.02.18

• Orginal Article • Previous Articles    

Location-weighted landscape index of non-point source pollution in Songhuaba Reservoir watershed

Ruijia YUAN()   

  1. Institute of Land & Resources and Sustainable Development,Yunnan University of Finance and Economics, Kunming 650221, China
  • Received:2018-11-12 Revised:2018-12-15 Online:2019-02-25 Published:2019-02-25


To ensure the drinking water safety of Songhuaba Reservoir and to promote the prevention and control of water pollution in Dianchi watershed, this study took the non-point source pollution as the research object. Through analyzing the contribution of the different landscape in the formation of non-point source pollution in the watershed, the weights of each ‘source’ and ‘sink’ landscape were characterized by expert evaluation method. The relationship between landscape pattern and non-point source pollution was identified quantitatively from the whole watershed and the three spatial factors levels (slope degree, relative elevation, and distance) by the location-weighted landscape index. The results showed that: (1) All of the location-weighted landscape indexes are less than 0.50, demonstrating that the watershed is the ‘pollution-interception’ landscape pattern in the current, no matter from the whole watershed or from the spatial factor levels. It means that there is few non-point source pollution out from the watershed outlet now, in theory. (2) The result of LWLIslope degree>LWLIrelative elevation>LWLIdistance indicates that in this watershed, focusing on the protection of the ‘sink’ landscape on the high-altitude and steep slope zone could not only prevent the formation of new “pollution contribution” landscape pattern, but also could strengthen the existing landscape pattern of ‘pollution-interception’ in isolation circle. It could effectively block the outflow of soil and nutrients losing by the dry land. The dry land is the largest contributor to non-point source pollution load, is also the ‘source’ landscape with the largest area, and is located in the middle-high elevation and sloping fields in Songhuaba Reservoir watershed.

Key words: non-point source pollution, ‘source’ or ‘sink’ landscape pattern;, LWLI(location-weighted landscape index), Lorenz Curve theory, Songhuaba Reservoir watershed