Quantification of the Impact of Land Use and Land Cover Changes upon Nitride Cycling Values in Karst Ecosystem: A Case Study in Northwest, Guangxi, China
Through the techniques of remote sensing (RS) and geographic information system (GIS),we analyzed the spatial distribution of NCV for the typical karst region in Northwest Guangxi,China in 1985,1990,2000 and 2005,using Landsat TM images,weather data and geographical data.Results showed that:NCV decreased firstly and then increased,but the NCV of 2005 was less than that of 1985.NCV were 33.08million Yuan,21.26 million Yuan,30.04 million Yuan and 31.33 million Yuan in 1985,1990,2000 and 2005respectively.Woodland and shrub were the two largest contributors to total NCV.The total ratios of them were 77.18％,76.15％,79.86％ and 74.50％ in the four years.While NCV of residential and barren rock were low,and the total ratios of them were only 0.60％,0.47％,0.47％ and 0.77％.NCV declined from west to east,from mountain to peak-cluster depressionareas,and increased in typical karst areas,but distinctly decreased in non-karst areas.Our study indicates that ecosystem conditions are improving because of the application of rocky desertification control policies,such as ecological migration and returning farmland to forest.
karst northwest Guangxi, China nitride cycling value land use and land cover
ZHANG Mingyang WANG Kelin CHEN Hongsong ZHANG Chua hua LIU Huiyu
Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agricul College of Geography Science, Nanjing Normal University,Nanjing 210024
国内会议
北京
英文
302-309
2009-10-20（万方平台首次上网日期，不代表论文的发表时间）