易地扶贫搬迁项目区土地利用合理性评价

合理利用土地资源是实施易地扶贫搬迁项目的内在要求。为探明扶贫搬迁项目区土地利用合理性及其制约因素,进一步给项目区土地资源利用指明方向。该文以中国西部山区典型贫困县——云南寻甸县的3个典型易地扶贫搬迁项目为实例,分析了搬迁项目区土地利用特征及原因,并对项目区土地利用合理性进行了评价研究。结果表明:1)在脆弱的自然地理环境及有限的项目投入资金成本等因素的限制之下,安置区(迁入区)用地以建设占用耕地为主,占用其他地类(林地和荒草地)为辅,新增建设用地比例较大。且占地地块坡度较陡,6°～25°地块是主要安置区域,少数安置区地形坡度大于25°。2)短期内,受到区域物资供应短缺、产业发展困难及传统文化思想和生活习俗等因素的制约,迁出区宅基地复垦、陡坡耕地退耕还林存在明显滞后现象。3)3个典型项目区土地利用合理度值均在0.50以上,其中,打磨箐搬迁项目为0.530 9,处于"低度不合理"等级;迤郎库搬迁项目和上龙潭箐搬迁项目分别为0.605 3和0.642 6,均处于"低度合理"等级。安置区地形坡度(I1)、迁出区宅基地复垦率(I6)与迁出区陡坡耕地退耕率(I7)是项目区土地利用合理性的共同制约因素。安置区离散度(I3)与安置区建设所占地类(I9)对项目区土地利用合理性产生不同程度的影响。4)安置区地形坡度(I1)、迁出区宅基地复垦率(I6)、迁出区陡坡耕地退耕率(I7)及安置区建设所占地类(I9)4个评价指标亦是全县易地扶贫搬迁项目区土地利用合理性的主要影响指标。

Evaluation on rationality of land use at poverty alleviation relocation project area

It was an inherent requirement for rational utilization of land resources to the implementation of Poverty Alleviation Reallocation. In this paper, we analyzed characteristics, causes and rationality of land use at three poverty alleviation reallocation project area in Xundian which is a typical mountainous poverty county in Yunnan province located at southwest of China, with help of field surveying(random sampling for door to door questionnaire survey), GIS technology (coordinate conversion, geometric Correction, pattern vectorizaton and spatial overlay analysis, etc.) and other technical methods, so as to finding out rationality and constraints of land use and define directions for rational utilization of land resource for those project areas. Results showed that limited by the fragile physical environment and low input, resettlement area increased a large number of new construction land which mainly transferred from cultivated land and the other transferred from forest land and grassland in poor mountainous area. Those new added construction lands mainly located at slope area among 6° to 25°, few construction land even located in the areas above 25°. The results also showed that it was significantly lagged for land reclamation from homestead and reforestation from steep slope cropland at the out-migration area restricted by shortage of necessities, challenges of existing industries, traditional cultural habits and life styles. In addition, reasonability indexes were above 0.50 for the three studied project areas. Shanglongtanqing and Yilangku had reached low-rationality level with 0.642 6 and 0.605 3, respectively, Damoqing had the low-irrationality level with 0.530 9. The common factors which affected land use rationality included slope at the resettlement area (I1), reclamation rate from homestead (I6) and reforestation rate from steep slope cropland (I7) at the out-migration area. The other factors such as resettlement area dispersion (I3) and land-use type transferred into new added construction land at the resettlement area (I9) had some extent influences on land use rationality. Moreover, our results showed that the main impact factors which influenced land use rationality for the whole Xundian county included slope of resettlement area (I1), reclamation rate from homestead at out-migration area (I6), reforestation from steep slope cropland at out-migration area (I7), and land-use type transferred into new added construction land at the resettlement area(I9). It was necessary to implementing the policy strictly, taking full account of both regional land resources and environmental conditions, planning spatial layout for project land properly for the further poverty alleviation reallocation project. Measures should be implemented such as reclamation from homestead and reforestation from steep slope cropland at out-migration area without delay, and improve living environment practical at poor mountain areas.