基于农业用地和地形约束的陇南山区适宜人口规模估算

陇南山区地形复杂，耕地不足，经济贫困，人口对资源环境的压力较大。研究适度人口容量对于地震灾后重建、缓解贫困以及保护长江上游的生态安全具有重要意义。以人均粮食和经济水平两个指标来估算温饱、宽裕和小康3个水平上的人口承载量，测度人口和农业资源的关系。并基于地形复杂度计算劳动用工及可抚养人口。结果表明：目前陇南10县(区)的人口在温饱生活水平下尚有超载。以小康生活为标准，适宜人口规模约为135万。经营现有的农耕地和林地需要100.81万劳动力，可抚养人口191.54万人，加上城镇人口总人口为 231.03万。这个人口规模实现温饱有余而宽裕不足，难达小康目标。“人口 农业用地 劳动力”之间形成了一个怪圈，决定了陇南山区农村实现小康目标的艰巨性和复杂性。为此，陇南山区的灾后重建和区域可持续发展需要创新思路，多方并举.

ESTIMATION OF OPTIMUM POPULATION SCALE BASED ON FARM LAND AND TERRAIN CONSTRAINTS IN THE MOUNTAINOUS REGION OF SOUTHERN GANSU PROVINCE 

Due to terrain complexity and deficiency of the arable land,local population has produced a heavy pressure to resources and environment in the mountainous region of southern Gansu.Peasants live in poverty.It is provided with important signification to study on the optimum human population size for reconstruction after the earthquake disaster,poverty alleviation and protection of the ecological security of the upper Yangtze River.Based on two indexes,per capita grain and economic level, this paper estimated local human carrying capacity on three levels,the subsistence life, the relative ample life and the well off life, and measured the relationship between population and agricultural resources.Meanwhile,on the basis of terrain complexity,we estimated the labor number and the population size that they could support.The result shows that total population size is overloaded even at the subsistence level in this region.Taking well off life as a standard,the optimum population size is 135 million,which is about a half of the existing population.Labor forces of 1.008 1 million are needed to make use of present arable land and forestland for production activities,and the population that they can support is 1.915 4 million.The total population will be 2.310 3 million when the population in towns is included.This population size is a level low enough to realize subsistence life,but too high for relative ample life and even more difficult to realize well off life. The strange circle existing among “population—farmland—labor force” has determined arduousness and complexity to realize the target of well off life in the mountainous region.Therefore,innovation thoughts and multiple measurements are needed for reconstruction after the earthquake disaster and regional sustainable development in this region.