Production Of Chinese Grassland Classification Map Based On Integrated Orderly Classification System And AMMRR Interpolation Method

Under the guidance of IOCSG, interpolation methods of Analytic Method based on Multiple Regression and Residues (AMMRR), Inverse Distance Weighted (IDW), Ordinary Kriging (OK) and Co-Kriging (CK), in conjunction with DEM and meteorological data as main data source consisting annual accumulative temperature (>0℃Σθ) and annual precipitation (r) of 2 796 stations located on China, were applied into experimentation of spatial interpolation. Following, the interpolation precision were validated and the effects were compared. Grassland classes and humidity (K) in China were classified in details via spatial overlay analysis (algebraic operation and logical operation) on GIS platform and the modifiedΣθand r raster layers interpolated by AMMRR method, which with the highest interpolation precision and best interpolation effect. The results found in this study were as following:(1) For bothΣθand r, Std. Deviation and Std. Error Mean caused by AMMRR method were obviously smaller than other three interpolation methods. Meanwhile, the correlation of AMMRR method was distinctly higher than other three interpolation methods. In order to ensure simulative results is close to reality and reduce regression error, regression equations between meteorological elements and longitude, latitude, elevation were constructed to perform residual raster, which was used to modify regression raster.Simulative results showed thatΣθ, r and K generally present the increasing trend from northwest to southeast exception of Tibetan Plateau. The interpolation effect could embody the horizontal and vertical zonality rule ofΣθand r in largest research area and complicated topography, which was better than other three interpolation methods.(2) According to IOCSG, Chinese vegetation can be classified into 41 classes exception ofⅦA7. Frigid perhumid rain tundra,alpine meadow (ⅠF36) with the largest area of 1.15×106km2 and ratio out of 10% mainly distributes in the regions with elevation above 3 000m in Gansu Province, Qinghai Province and Tibet Autonomous Region. Followd by Warm temperate-extrarid warm temperate zonal desert (ⅣA4) and Cool temperate-arid temperate zonal semidesert (ⅢB10), which mainly distributed in Xinjiang Province-Hexi Corridor of Gansu Province-Inner Mongolia. The grassland classes with area ratio more than 5% also included Cold temperate perhumid taiga forest (ⅡF37), Warm-perhumid deciduous-evergreen broad leaved forest (ⅤF40), Sub-tropical perhumid evergreen broad leaved forest (ⅥF41), Cool temperate-humid forest steppe, deciduous broad leaved forest (ⅢE31) and Cool temperate perhumid mixed coniferous broad leaved forest (ⅢF38).(3) According to classification map of Chinese grassland, There distributed Frigid-extrarid frigid desert,alpine desert (ⅠA1) and Cold temperate-extrarid montane desert (ⅡA2) in arid and semi-arid regions of northwest China. But, Frigid-humid tundra, alpine meadow(ⅠE29), Cold temperatehumid montane meadow (ⅡE30) and Frigid perhumid rain tundra,alpine meadow (ⅠF36) in cool temperature zone regions in northeast China, and Tropical-humid seasonal rain forest (ⅦE35), Sub-tropical perhumid evergreen broad leaved forest (ⅥF41) and Tropical-perhumid rain forest (ⅦF42).In coastal southeast China, there distributedⅦF42-ⅥF41-ⅤF40-ⅣF39 with increasing latitude and decreasing temperature from south to north; In northeast China, there distributedⅢF38-ⅢE31-ⅢD24-ⅢC17 with far away ocean and decresing K from east to west; From Shandong Province, Hebei Province and Hexi Corridor, there distributedⅣE32-ⅣD25-ⅣC18- ⅣB11-ⅣA4 with decreasing r. This was highly agreement with searching map of IOCSG categories, and fully embodied the horizontal and vertical zonality rule of grassland classes. There are 14 grassland classes with area ratio between 1% and 5%, and 19 with area ratio short of 1%. The spatial distribution of 41 grassland classes in China is generally agreement with its distribution rules on IOCSG searching map. In northwestern China, there mainly distribute Frigid-extrarid frigid desert,alpine desert (ⅠA1) and Cold temperate-extrarid montane desert (ⅡA2). But, there mainly distribute Frigid perhumid rain tundra,alpine meadow (ⅠF36) on the east and Tropical-perhumid rain forest (ⅦF42) on the south, which fully reflect the horizontal and vertical zonality rule of grassland classes.In short, the classification results of Chinese grassland classes based on improved interpolation method could reflect the horizontal and vertical zonality rule of grassland classes in largest research area and complicated topography and complement the visual expression technique of IOCSG. It also could illustrate the scientificity of IOCSG and had import theoretical value and practical significance for grassland classification and management.