煤矿区土壤有机碳含量的遥感反演与分布特征

Remote Sensing Inversion and Distribution Characteristics of Soil Organic Carbon Content in Coal Mining Area

高光谱数据与多光谱影像结合能实现区域高精度、大面积的土壤有机碳含量反演。以山东省鲍店矿区表层0-20cm土壤有机碳含量为研究对象,采用波段平均法把高光谱的窄波段拟合成GF-1 WFV影像的宽波段,建立土壤有机碳含量的高光谱模型,进而通过比值订正法,将最优高光谱模型校正到多光谱模型并通过决策树分类获取土壤有机碳含量空间分布状况,结合土地利用现状分析土壤有机碳含量分布特征。结果表明:(1)通过波段拟合和比值订正获得的多光谱模型,检验决定系数为0.76,可以稳定实现矿区土壤有机碳含量的反演。(2)研究区土壤有机碳含量范围为0.71~38.15g/kg,均值为14.12g/kg,总体上处于中等水平;区域内土壤有机碳含量以11.60~17.40g/kg为主,其次是5.80~11.60g/kg,分别占据48%,29%。(3)采矿区和部分道路、居民点的有机碳含量偏高,耕地处于中等水平,林地和草地含量较低;塌陷地形成的水域周围有机碳含量明显偏低。

The combination of hyperspectral data and multi spectral image enables high-precision and largearea inversion of soil organic carbon content to be achieved.Taking the organic carbon content in 0-20 cm soil layer of Bao Dian mining area in Shandong Province as the study object,this study first applied the band averaging method to synthesize the hyperspectral narrow band into the wide band of GF-1 WFV,based on which the hyperspectral model of soil organic carbon content were established.Then the optimal hyperspectral model was corrected to the multispectral model through the ratio correction method,and the spatial distribution map of soil organic carbon content was obtained through decision tree classification.Finally,the distribution characteristics of soil organic carbon content were analyzed combined with the land use status map.The results showed：（1）The determination coefficient of the multi spectral model obtained by band fitting and ratio correction was 0.76,indicating that the soil organic carbon content could be retrieved steadily via the model.（2）The soil organic carbon content in the study area varied from 0.71 to 38.15 g/kg,with a mean value of 14.12 g/kg,which was at a medium level in general.The soil organic carbon content was mainly 11.60 ～ 17.40 g/kg,followed by 5.80 ～ 11.60 g/kg,occupying 48% and 29% respectively in the study area.（3）The soil organic carbon content of mining area,some roads and settlements was high.The soil organic carbon content of cultivated land was at medium level,and the content in woodland and grassland was relatively low.The content of organic carbon around the subsidence area was obviously lower than that in other land use types.