Land Population Carrying Capacity In The Karst Region

The karst region has a fragile ecological environment and a large rocky desertification area, which causes people’s poverty and the contradiction between human and land. In order to solve the above problems, predicting land production potential and land population carrying capacity scientifically is indispensable. This study took Baise city, Guangxi as an example and aimed to estimate land production potential and land population carrying capacity of Baise using the method of "agricultural ecological zone" and suitable method for the prediction of land production potential in karst area. Then the countermeasures of rational utilization of land resources were put forward. The results were outlined as follows:1. Rice had the highest in light temperature, climate and land production potential among the major crops in Baise, followed by maize, soybean and sweet potato. The land production potential of rice was the highest in Tiandong, whose volume was10304.8Kg/hm2, the rest regions were between7000-9000Kg/hm2. The land production potential of maize was between6000-9000Kg/hm2, the land production potential of soybean was between2000-4000Kg/hm2, and the land production potential of sweet potato was the lowest among the major crops in Baise, the lowest region was Lingyun at798.3Kg/hm2.2. Land bearing capacity of Baise was relatively low. The overloaded counties were: Tiandong, Pingguo, Debao, Lingyun, Longlin, Youjiang and Napo, among them, the land bearing ratio in Youjiang and Napo was close to or reached2.0, being seriously overloaded. Land bearing capacity in Xilin will be in good condition in2015and2020, and then goes full in2025. Land bearing capacity in Tianyang, Tianlin, Jingxi and Leye will be full in2015,2020and2025. 3. Taking Nanning as a comparison, the relative resources bearing capacity was calculated. The change of relative land resource bearing capacity agreed with the change of arable land, indicating that arable land had a direct impact on relative land resource bearing capacity. The dynamic variation of relative land resource bearing capacity was consistent with the comprehensive bearing capacity of relative resources, showing that the comprehensive bearing capacity in Baise was mainly limited by land resources.According to land production potential and land population carrying capacity in Baise, we should adjust the industrial structure and increase the proportion of breeding industry and tourist industry. It will not only promote the rational utilization of land resources, but also solve the contradiction between people and land, and increase farmers’ income.