Remotely sensed estimation of maize residue cover in typical agricultural regions of Songnen Plain

Crop residue cover is one of the most important components in conservation tillage, and plays a significant role in reducing soil erosion, improving crop water use efficiency and holding soil fertility.This study used partial least squares regression (PLSR) method, tillage indices and texture features to estimate maize residue cover (MRC) in the study area based on the Landsat-8 OLI image.The normalized difference tillage index (NDTI) and simple tillage index (STI) were significantly correlated with MRC.The regression between NDTI, STI and MRC was stronger than those tillage indices.The coefficient of determination (R²) was 0.86.There was no significant correlation between texture features and MRC in this study.The correlation between Band5_mean and MRC(R²=0.384) was better than other texture features.The accuracy of MRC estimation using combination method was higher (R²=0.907, RMSE=6.21) than that using tillage indices (R²=0.86, RMSE=5.77)and texture features (R²=0.153, RMSE=10.36) respectively.The results indicated that the combination method would be used to invert MRC.