关键词: GIS, 关中-天水经济区, 地形起伏度, 人口分布

Abstract:

With the degeneration of environment and acceleration of urbanization, human environment has attracted great attention worldwide. As one of the key factors, the relief degree of land surface is an important indicator for natural evaluation, and it also has high accuracy and practical application in small scale residential environmental evaluation. Based on lattice digital elevation model of scale 1∶25 0000 in Guangzhong-Tianshui economic region, using the window analysis and spatial analysis model of ARCGIS software, this article extracts the relief degree of land surface and population distribution in Guanzhong-Tianshui economic region. From the characteristics of proportion, spatial distribution and height, it also systematically analyzes the discipline of the relief degree of land surface and its relationship with the distribution of population in Guanzhong-Tianshui economic region. The study has shown that: 1) The relief degree of land surface in Guanzhong-Tianshui economic region is dominated by middle and low value, and its topographic area is less than 2.4 occupying 96.66% of the total area, and the average proportion occupying 32.4% of the whole area. The higher is the relief degree of land surface, the lower is the proportion of plains, and vice versa; 2) The relief degree of land surface in Guanzhong-Tianshui economic region presents such spatial patterns that the south and north are higher and the middle is lower, and there is the maximum value in Taibai Country in Baoji City and the minimum value in Guanzhong plains. The variation is not apparent on the longitude, and the degree of latitude increases after the first drop no matter from South to North or from North to South;3)As the altitude increased, the degree presents a rising trend but has not much change; 4) The relief degree of land surface has a strong impact on the regional distribution, nearly 90% residents in Guanzhong-Tianshui economic region lived in the area where less than 1.5 degree, the curved fitting of population density and topographic is very high; 5)The relational area of topographic and population distribution have significant difference, the topographic has obvious relation with population distribution, but the relationship of the topographic is smaller in four countries in Shangluo and Tianshui cities. To sum up, the relief degree of land surface can better reflect the topographic feature and reveal its regularities of space in Guanzhong-Tianshui economic region. Empirical research shows that, as one of the key factors, the relief degree of land surface is an important indicator for natural evaluation; it also has high accuracy and practical application in small scale residential environmental evaluation. In summary, the RDLS model established in this paper can not only reflect the natural environment suitability for human settlements in Guanzhong-Tianshui economic region, but also can illustrate the spatial distribution rules of it very well.

Key words: GIS, Guanzhong-Tianshui economic region, the relief degree of land surface (RDLS), population spatial distribution