摘要
以2007年23时相MODIS增强型植被指数为数据源,利用决策树分类方法对海河流域生态系统进行了分类,分析了生态系统空间分布格局及其与地形因子的关系。结果表明:利用MODIS植被指数时间序列数据进行的生态系统分类,精度达到85.6%,Kappa系数为0.82。农田、城市和湿地生态系统分别占流域总面积的53.8%、1.0%和1.3%,主要分布在海拔<200m的平原;森林生态系统占22.5%,主要分布在500～1000m的低山;草地生态系统占21.4%,主要分布在1000m以上的区域。农田、城市和湿地生态系统主要分布在坡度<2°的地区,森林和草地生态系统主要分布在5°～15°的地区。随着坡度增加,农田、湿地和城市生态系统所占比例减小,森林生态系统所占比例增加,草地生态系统所占比例则先增加后减小。
Based on the multiple-temporal MODIS EVI data in 2007, and by using decision tree classifier, the ecosystems in Haihe River Basin were classified, and their spatial pattern as well as its relationship to topography was analyzed. The classification based on the MODIS EVI data had an overall accuracy of 85.6% and a Kappa coefficient of 0. 82. Different ecosystems distrib- uted at different elevations. Cropland, urban, and wetland ecosystems mainly distributed on the plains below 200 m, occupying 53.8% , 1.0% , and 1.3% of the total area, respectively, forest ecosystem mainly located on the low mountains between 500 m and 1000 m, accounting for 22.5%, while grassland ecosystem mainly distributed at the elevations above 1000 m, accounting for 21.4%. Different ecosystems showed different distribution trend to slope. Cropland, urban, and wetland ecosystems mainly distributed on the slopes 〈 2°, while forest and grassland ecosystems were mainly on the slopes between 5° and 15 °. With increasing slope, the percentages of cropland, wetland, and urban ecosystems decreased, that of forest ecosystem increased, while grassland ecosystem had a decreased percentage after an increasing to a peak.
出处
《生态学杂志》
CAS
CSCD
北大核心
2009年第6期1149-1154,共6页
Chinese Journal of Ecology
基金
国家重点基础研究发展计划资助项目(2006CB403402)
国家自然科学基金创新群体项目(40621061)
