基于GIS的山区人口压力测算模型——以四川省凉山州为例

Population Pressure Assessment Model of Mountainous Areas:A Case Study of Liangshan Yizu Autonomous Prefecture, Sichuan Province

从人口压力构成要素和山区实际情况出发,构建了山区人口压力测算模型。该模型包括城镇人口压力指数、农村人口压力指数和人口自然增长率3个构成要素,综合反映了山区人口数量压力特征。应用该模型对四川省凉山州的人口压力指数进行了测算,结果表明:①凉山州人口压力指数的平均值为4.95,属"一般"水平。人口压力"小"、"较小"、"一般"、"大"、"极大"的县市分别占的23.53%、11.76%、29.41%、29.41%和5.88%;②人口压力指数具有明显的空间集聚性,并受到地形条件的制约,凉山州东部、东北部的大、小凉山地区人口压力大,安宁河谷、凉山州南部低山、中山区和盐源盆地人口压力小;③人口压力指数与贫困发生率、生态脆弱度之间具有较高的相关性,说明人口压力大和生态环境脆弱性高是导致山区贫困的一个因素,应加强贫困山区社会经济与生态环境的协调性研究。

Population pressure is an important factor in the development of mountainous areas. In order to assess the population pressure of mountainous areas, a new population pressure assessment model was proposed in this paper. It consisted of three components, i.e., urban population pressure index, agricultural population pressure in- dex and natural population growth rate. Taking Liangshan Yizu Autonomous Prefecture of Sichuan Province of China as the study area, the urban population pressure index, agricultural population pressure index and popula- tion pressure index were computed by the model. We had three main conclusions. I） The mean value of popula- tion pressure index of the study area is 4.95, which is at a ＂normal＂ level of population pressure. The ＂small＂level, ＂smaller＂ level, ＂normal＂ level, ＂large＂ level and ＂very large＂ level respectively account for 23.53%, 11.76%, 29.41%, 29.41% and 5.88% of the total study area, respectively. 2） Topography is an important factor of population pressure of the study area, with the population pressure being higher in the eastern and northeastern parts, and the population pressure lower in the valley of Anning River, the south of the study area and the Yanyu- an basin. 3） The population pressure index is related with the incidence of poverty and the ecological frangibili- ty, so the result also proves that the high population pressure and ecological frangibility are important factors leading to the poverty in the mountainous areas.