宁夏土地利用结构信息熵时空变化分析

Analysis on temporal-spatial changes of information entropy of land-use structure in Ningxia

研究土地利用结构时空变化对区域的空间布局和规划以及土地利用的优化配置有着重要的意义.用信息熵理论,计算宁夏2000—2010年土地利用结构信息熵时间和空间变化,并分别从自然因素、政策因素和社会经济因素进行了分析,应用灰色关联分析模型,揭示了社会经济因素中的各类因素与土地利用结构信息熵的关联度.结果表明,从整体来看,耕地、牧草地、其他土地所占比例下降,工矿用地、交通用地、林地所占比例上升;信息熵呈现波动性上升的变化,在空间上,高熵值区分布在宁夏北部,低熵值区分布在宁夏中南部.各类影响因素中,水资源条件的优劣对土地利用信息熵影响较大;政策因素方面,由于受退耕还林和生态移民工程的影响,宁夏各类土地利用类型转化明显,变化剧烈,熵值出现变动;社会经济因素中的总人口、第三产业比例和城市化水平是强关联因素,对宁夏的土地利用结构起着重要的作用,说明城镇化和服务业的人口转移效果对土地利用的影响明显.

Based on the information entropy theory, temporal-spatial changes of land-use structure information entropy were studied with data from 2000 to 2010 of Ningxia. The influence factors were analyzed from three aspects, such as natural factors, policy factors and social economic factors. The correlation between land use structure and the social economic factors were revealed by applying Grey Correlation Model. Results show that the proportion of cultivated land, grassland decreased, the proportion of industrial land and mining land, forest land, traffic land increased; and the change of information entropy raised wavily, high entropy value area distributed in northern Ningxia , low entropy distributed in central and southern Ningxia. Conditions of water resource had great influences on land use information entropy in natural factors; and on the hands of policy factors, for the effects of returning farmland to forest and ecological immigrant project, various land use types transformed obviously in Ningxia, which made the entropy change. The total population, the proportion of the tertiary industry and the level of urbanization were strong correlation factors, which played important roles in the land use structure of Ningxia, and the oooulation of urbanization and service industry transfer imoacted land use ~eatlv.