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.
人类活动强度多用于衡量人类对自然生态的影响程度,具有明显的空间差异性。本研究以云南省拉市海流域为例,采用SPOT遥感影像对土地利用数据进行更新,通过对不同土地类型赋权得到格网化的土地利用强度综合指数,并将其作为基础人类活动强度。同时,又纳入了当地的骑马和划船两项主要旅游活动,基于马场位置和马匹数量以及船只数量,采用地理信息系统的核密度分析方法进行空间定量化,并在100 m×100 m空间尺度上与基础人类活动强度进行叠加,得到更为精确的综合人类活动强度,并对其空间差异进行分析。结果表明: 格网化和核密度分析在提高空间分析精度的同时,将空间上的叠加和扩散效应体现出来;在拉市海流域综合人类活动强度图中,水域的入海口处强度值最高,海中心强度值最低,整体强度呈现从四周向中间逐渐减弱的趋势,陆域的居民点为强度最高区域,农业用地聚集区强度值处于中间水平,海拔较高的林区人类活动强度较低;拉市海水域综合人类活动强度值变化最明显,与基础人类活动强度差异较大。云贵高原湿地景区当地特色旅游活动较多,但并未改变其土地利用类型,因而对其进行人类活动强度量化时,需将其另外考虑在内。.
Keywords: geographic information system; gridding; human activity intensity; kernel density analysis; spatial quantification.