基于高光谱遥感的新疆北疆地区土壤砂粒含量反演研究

Soil sand content retrieving of bare soil in north Xinjiang based on hyper-spectral remote sensing

土壤砂粒含量是表征土壤质量的重要指标,探索建立基于高光谱遥感的区域土壤砂粒含量反演方法对区域土壤质量监测具有重要意义。通过野外采集的高光谱数据与MODIS影像相结合,遴选出土壤砂粒含量的敏感波段与反演方程,进行干旱区裸地土壤砂粒含量遥感反演研究。结果表明:430 nm为土壤砂粒含量的敏感波段,原始光谱经变换后的数值与土壤砂粒含量的相关系数在430 nm处达到最大值0.76;基于MODIS第3波段中心波长460 nm处的土壤原始光谱的反演精度最高,达到89.30%,与实际情况吻合较好,表明MODIS第3波段可以应用于干旱区裸地土壤砂粒含量的遥感反演。

Soil sand content is an import indicator that can reflect soil quality,and it is very meaningful to build the method that uses hyperspectral remote sensing to retrieve soil sand content at regional scale.In this paper,taking the north Xinjiang as the research region,the best band with the fine correlation coefficient and the best simulation method was found based on combining field hyperspectral data and MODIS images,and transferring the original soil reflectance spectrum into several forms.Some good results were gotten by retrieving the sand content of bare soil in north Xinjiang.The results show that 430 nm is the best band to retrieve soil sand content;the soil spectrum data transferred by logarithm＇s reciprocal could reach the maximum value at 430 nm,and the correlation coefficient was 0.76.MODIS band 3 could be used to retrieve soil sand content at regional scale;the one-dimension three-order regression model using the original spectrum data at 460 nm as independent variable could get the highest accuracy when retrieving soil sand content,and the accuracy could reach 89.30%.According to the retrieving result from bare soil by using the model built above,the soil sand content of bare soil was relative higher,and it could match the actual conditions well.