Improving ground cover monitoring for wind erosion assessment using MODIS BRDF parameters

摘要

AbstractMeasuring and monitoring controls on wind erosion can facilitate detection and prediction of soil degradation important for food security. Ground cover is widely recognised as an important factor for controlling soil erosion by wind and water. Consequently, maintaining ground cover (e.g., vegetation, crop canopy, crop residue) is a recommended management practice which is widely adopted by farmers and land owners. Wind erosion is a lateral or horizontal process and the amount of ground cover needed to maintain lateral cover (Lc=nbh/Swherenroughness elements occupy ground areaSand havebandhmean breadth and height, respectively) is not well-established. Soil may be removed from beneath or between crop and natural vegetation canopies depending on the width, height and distribution of cover types relative to wind direction and strength. Monitoring by repeated measurement or estimation of ground cover provides information to develop an understanding of its spatial and temporal variation. Fractional cover (fc) retrieved from optical satellite remote sensing (e.g., Moderate Resolution Imaging Spectroradiometer; MODIS) provides a consistent and repeatable measure of ground cover when viewed from above. Therefore,fcprovides an areal assessment of components of ground cover. Fractional cover is consequently not the most appro