[Spatial distribution of human activity intensity in Yunnan-Guizhou Plateau Wetland scenic area: A case study of Lashihai watershed in Yunnan Province, China].

Human activity intensity is mostly used to quantify the degree of human influence on natural systems, with obvious spatial variability. With Lashihai watershed in Yunnan Province as an example, we used SPOT remote sensing images to update land use data, and obtained a comprehensive index of land use intensity after gridding by assigning weights to different land types, which was considered as the basic human activity intensity. The local tourism activities (horseback riding and boating) were also included. The horseback riding and boating were spatially quantified according to the location of horse farms and the abundance of horses and boats which were superimposed with the basic human activity intensity on the spatial scale of 100 m×100 m to obtain a more accurate comprehensive human activity intensity and to analyze the spatial variations. The results showed that the gridding and the kernel density analysis improved the accuracy of spatial analysis and reflected the spatial superposition and diffusion effects. In the comprehensive human activity intensity map of Lashihai watershed, the highest intensity value of water area was at the mouth of the sea, the lowest intensity value was at the center of the sea, and the overall trend of intensity gradually decreased from the surrounding to the middle. The land settlement had the highest intensity, the intensity value of the agricultural land gathering area was at the middle level, and the intensity of human activities in the forestry area of higher altitude was lower. The comprehensive human activity intensity in the water area of the Lashihai watershed varied most obviously, and differed greatly from the basic human activity intensity. Although there were many local characteristic tourism activities in Yunnan-Guizhou Plateau Wetland scenic area, but their land use types did not change. We need to take them into account when quantifying the intensity of human activities.