Suitability evaluation and spatial capacity analysis for complex topography construction land area in southwest China: a case study of Tongzi county in Guizhou province

In the background of a new round reform and western development strategy, making suitability evaluation of construction land complex topography area in southwest China scientifically and accurately has an important guiding significance on the construction of local urban and rural development. We selected economic factor of construction, safety factor of construction, factor of the present situation of land use and ecological protection factor in Tongzi county as evaluation indexes, and ascertained the weight of each elastic indicator using the analytic hierarchy process method. By the support of GIS and RS technology, we combined the single-factor qualitative classification with the multi-factor weighted overlay analysis to make comprehensive suitability evaluation of construction land on the whole study area. And five different types of construction land were divided, namely, ‘excellent’, ‘very good’, ‘good’, ‘moderate’ and ‘poor’. The result shows that the area of ‘excellent’ construction land is 30.47 km2(0.95%), 101.46 km2(3.16%) of ‘very good’, 550.34 km2(17.16%) of ‘good’, and 664.69 km2(20.72%) and 1 860.65 km2(58.01%) of ‘moderate’ and ‘poor’, respectively. The land space bearing capacity is a population of 791 600, and the remaining population capacity is 170 900 persons.