Digital mapping of soil salinization based on Sentinel-1 and Sentinel-2 data combined with machine learning algorithms  

作　　者：Guolin Ma Jianli Ding Lijng Han Zipeng Zhang Si Ran 

机构地区：[1]Key Laboratory of Smart City and Environment Modelling of Higher Education Institute,Xinjiang University,Urumqi,800046,China [2]Key Laboratory of Oasis Ecology,Xinjiang University,Urumqi,830046,China

出　　处：《Regional Sustainability》2021年第2期177-188,共12页区域可持续发展（英文）

基　　金：This work was financially supported by the National Natural Science Foundation of China(41771470);the China Postdoctoral Science Foundation(2020M672776).

摘　　要：Soil salinization is one of the most important causes of land degradation and desertification,especially in arid and semi-arid areas.The dynamic monitoring of soil salinization is of great significance to land management,agricultural activities,water quality,and sustainable development.The remote sensing images taken by the synthetic aperture radar(SAR)Sentinel-1 and the multispectral satellite Sentinel-2 with high resolution and short revisit period have the potential to monitor the spatial distribution of soil attribute information on a large area;however,there are limited studies on the combination of Sentinel-1 and Sentinel-2 for digital mapping of soil salinization.Therefore,in this study,we used topography indices derived from digital elevation model(DEM),SAR indices generated by Sentinel-1,and vegetation indices generated by Sentinel-2 to map soil salinization in the Ogan-Kuqa River Oasis located in the central and northern Tarim Basin in Xinjiang of China,and evaluated the potential of multi-source sensors to predict soil salinity.Using the soil electrical conductivity(EC)values of 70 ground sampling sites as the target variable and the optimal environmental factors as the predictive variable,we constructed three soil salinity inversion models based on classification and regression tree(CART),random forest(RF),and extreme gradient boosting(XGBoost).Then,we evaluated the prediction ability of different models through the five-fold cross validation.The prediction accuracy of XGBoost model is better than those of CART and RF,and soil salinity predicted by the three models has similar spatial distribution characteristics.Compared with the combination of topography indices and vegetation indices,the addition of SAR indices effectively improves the prediction accuracy of the model.In general,the method of soil salinity prediction based on multi-source sensor combination is better than that based on a single sensor.In addition,SAR indices,vegetation indices,and topography indices are all effective variables for

关 键 词：SALINIZATION Digital soil mapping XGBoost Sentinel-1 Sentinel-2 Ogan-Kuqa River Oasis 

分 类 号：S15[农业科学—土壤学]