基于RF和SGT算法的子区优先建模对绿洲尺度 土壤盐度预测精度的影响

王飞,杨胜天,魏阳,杨晓东,丁建丽

Influence of Sub-Region Priority Modeling Constructed by Random Forest and Stochastic Gradient Treeboost on the Accuracy of Soil Salinity Prediction in Oasis Scale

WANG Fei,YANG ShengTian,WEI Yang,YANG XiaoDong,DING JianLi

表1 基于Landsat OLI（30 m）和DEM（8个空间分辨率）衍生的环境变量

Table 1 Environmental covariates derived from a 30 m spatial resolution DEM and 30 m Landsat imagery

变量组 Environment variable group 指数 Index 波段及其衍生变量 Band & derivatives 全波段;缨帽变换（亮度（TC1）,绿度（TC2）,湿度（TC3）,主成分分析（前三个波段） Bands;Tasseled Cap (brightness,TC1;Greenness,TC2; Wetness,TC3 ), Principal Component Analysis(PC1,PC2,PC3) 植被指数 Vegetation indices 归一化植被指数;土壤调节植被指数;增强植被指数;广义植被指数;冠层响应盐度指数[3];比值植被指数;两波段增强植被指数[30];扩展的归一化植被指数[31];扩展的增强植被指数[31] Normalized Difference Vegetation Index, NDVI; Soil Adjusted Vegetation Index, SAVI; Enhanced Vegetation Index, EVI; Generalized Difference Vegetation Index, GDVI[5]; Canopy Response Salinity Index, CRSI[3]; Simple Ratio Vegetation Index, SR; Two-Band Enhanced Vegetation Index, EVI2[30]; Extended NDVI, ENDVI[31]; Extended EVI, EEVI[31] 土壤相关指数 Soil-related indices 盐度指数（Salinity Index, SIT）[1];盐度指数（Salinity Index, SI）[1];盐度指数（Salinity Index（SI1）[1];盐度指数（Salinity Index, SI2）[1];盐度指数（Salinity Index, SI3）[1];盐度指数（Salinity Index, SIA）[1];盐度指数（Salinity Index, SIB）;盐度比值指数（Salinity Ratio, SAIO）[32];黏土指数（Clay Index, CLEX）[4] ;石膏指数（Gypsum Index, GYEX）[4];亮度指数（Brightness Index, BREX）[4];碳酸盐指数（Carbonate Index, CAEX）[4];FSEN= (B5-B7）/(B5+B7）[33];颜色指数（Color Indices -色相Hue, 饱和度 Saturation, 色调Value）;归一化热感指数（Normalized Difference Infrared Index, NDII）[4];全球植被湿度指数（Global Vegetation Moisture Index, GVMI）[34];地表温度（Temperature） DEM衍生因子 Dem derivatives 河道相关：谷深（Valley Depth ,VD）;与河网的垂直距离（Vertical Distance To Channel Network ,VDCN）;水文学相关：坡长因子（LS-Factor, LSF）;地形指数指数（Topographic Wetness Index, TWI）;坡长（Slope Length, SL）;通视度（Sky View Factor, SVF）;地形位置指数（Topographic Position Index, TPI）;多尺度谷底平整度（Multiresolution Index Of Valley Bottom Flatness（MRVBF And MRRTF））,坡高（Slope Height, SH）,归一化高度（Normalized Height, NH）,标准化高度（Standardized Height, STH）,坡度中值位置Mid-Slope Position（MSP）,地表纹理（Terrain Surface Texture, TEX）,汇流累积量（Flow Accumulation, FA）;形态：截面曲率（Cross-Section Curvature, CSC）,纵向曲率（Longitudinal Curvature, LC）,相对坡度位置（Relative Slope Position, RSP）,流域坡度（Catchment Slope, CS）（SAGA Development Team, 2011）