基于GIS的抚仙湖流域土地利用时空变化研究

高原湖泊是流域内生产生活的重要水源地,维系着当地经济社会的发展,对于调节气候和美化环境起着不可替代的重要作用。由于城镇化的推进和旅游产业的发展,湖泊流域空间格局发生变化,高原湖泊环境污染加剧。以云南省抚仙湖流域为研究对象,运用GIS空间分析技术和数理统计方法,基于2005～2015年3期遥感影像从土地利用幅度变化、土地利用转移类型和土地利用动态度3个方面分析了流域10 a来土地利用时空变化特征。结果表明:①抚仙湖流域土地利用类型以湖泊水面、有林地、旱地、水田和草地为主,水田、有林地和建设用地面积增长,旱地、草地和灌木林地面积减少,园地、湖泊水面和未利用地面积先增后减,水库坑塘先减后增;②土地利用转换类型以农用地向建设用地转移、耕地内部转移和耕地向林地转移3类为主;③不同时期不同地类不同区域的土地利用动态度存在较大差异,2010～2015年与2005～2010年相比,变化更为剧烈,其他建设用地动态度最高,湖泊水面动态度最低,动态度较高的区域分布于湖泊北岸以及西岸中部,而流域北部边缘、西部边缘的动态度较低。研究成果可为该流域生态环境的保护和土地资源的可持续利用提供理论参考。

Spatial-temporal change of land use in Fuxian Lake Basin based on GIS from 2005 to 2015

Plateau lakes are important water sources for production and living conditions, maintaining the development of local economy and society, which play an irreplaceable role in regulating climate and beautifying the environment. Due to the promotion of urbanization and the development of tourism industry, the spatial pattern of lake basins has changed, and the pollution of plateau lakes has intensified. In this paper, Fuxian Lake Basin was taken as the research object. Based on the three remote sensing images from 2005 to 2015, GIS spatial analysis technology and mathematical statistics method, the temporal and spatial change characteristics of land use in the past 10 years were analyzed from three aspects: land conversion amplitude, conversion type and dynamic degree. The results showed that: (1) the lake water, forest lands, dry land, paddy field and grassland were the main land use types in Fuxian Lake Basin, the area of paddy field, forest, construction land increased, the dry land, grassland and shrub land decreased. The garden plot, lake water, and the unused land increased at first and then decreased, the pits and ponds of the reservoir decreased at first and then increased; (2) The land conversion types were mainly the transfer from agricultural land to construction land, the internal transfer of cultivated land, and the transfer from cultivated land to forest land; (3) From 2005 to 2015, there was a big difference in land use dynamics between different periods, land types and regions. During 2010-2015, the change was more severe than the previous five years. The other construction land had the highest dynamic degree, and the lake water surface had the lowest dynamic degree. The regions with higher dynamic degree were distributed in the northern shore of the lake and the central part of the western bank, while the dynamic degree on the northern and western margins of the basin were lower. The research results can provide theoretical reference for the ecological environment protection and the sustainable utilization of land resources in this basin.