A Sensitive Band to Optimize Winter Wheat Crop Residue Cover Estimation by Eliminating Moisture Effect

• Main Authors: Yamei Wang, Shuhe Zhao, Wenting Cai, Joon Heo, Fanchen Peng
• Format: Article
• Language: English
• Published: MDPI AG 2019-05-01
• Series: Sustainability
• Subjects: winter wheat; crop residue cover; cellulose absorption index (CAI); <i>R</i>₂₀₀₅
• Online Access: https://www.mdpi.com/2071-1050/11/11/3032

Crop residues can retain soil moisture and increase soil organic matter. Crop residue cover is also a hot issue in agricultural remote sensing. Crop residue cover can be estimated linearly with cellulose absorption index (CAI), while moisture of crop residues and soil would reduce the accuracy of crop residue cover estimation. Crop residue and soil were used as materials to carry out the laboratory experiment to reveal the impact of moisture on crop residue cover estimation and eliminate said impact. This paper discovered a sensitive band, <i>R</i>₂₀₀₅, which can invert water content of materials to eliminate moisture effect and improve estimation accuracy of crop residue cover. In terms of inverting water content, compared with two ratio water indices proposed in 2016 (<i>R</i>_1.6/<i>R</i>_1.5, <i>R</i>_1.6/<i>R</i>_2.0), using <i>R</i>₂₀₀₅ can increase R² from 0.828 to 0.935 and decline root-mean-square error (RMSE) from 0.12 to 0.07. At the point of results validation, R² is 0.958 and RMSE is 0.06, indicating <i>R</i>₂₀₀₅ has a high accuracy. Another advantage of <i>R</i>₂₀₀₅ is that it is more suitable to promote to actual production because of simple and efficient band calculation.