C-SAR/01, the successor of China’s Gaofen-3 Satellite, which launched on 23 November 2021, is the first synthetic aperture radar (SAR) satellite to be launched in China’s civil space infrastructure plan and has served as an invaluable data resource. Radiometric calibration and validation are prerequisites for the quantitative application of SAR data. In this study, the radiometric calibration experiments of C-SAR/01 data of the ultra-fine strip (UFS) and fine strip I (FSI) modes were conducted applying flexible automatic triangular trihedral corner reflectors deployed in Xilinhot SAR satellite calibration and validation site. Accordingly, the image quality and radiometric calibration accuracy were evaluated. The results show that the spatial resolution, peak sidelobe ratio, and integrated sidelobe ratio of UFS and FSI mode data of C-SAR/01 are better than those of the design indexes, and the calibration results from the integral method are more stable than those from the peak method. Furthermore, the standard deviation of the calibration constant for UFS mode data is 0.234 dB, with the relative and absolute calibration accuracies obtained as 0.233 and 0.532 dB, respectively, whereas the standard deviation calibration constant for FSI mode data is 0.198 dB, with its relative and absolute calibration accuracies evaluated as 0.199 and 0.333 dB, respectively.

Wind erosion is one of the most severe environmental problems in arid and semi-arid regions, posing a serious threat to ecological security and human settlements. Afforestation is widely acknowledged as a practical strategy for mitigating wind erosion. However, quantitative assessments of the relationship between forest restoration and wind erosion control remain limited, particularly over long temporal scales and at fine spatial resolutions. This study takes Duolun County, Inner Mongolia, as a representative case to examine the role of large-scale forest restoration in controlling wind erosion. Specifically, land use dynamics from 1985 to 2024 were mapped using a time series of Landsat imagery to identify forest expansion. Then, the Revised Wind Erosion Equation (RWEQ) was applied to simulate the spatiotemporal variations in wind erosion and sand fixation. Finally, a scenario-based framework contrasting forested and non-forested conditions was used to isolate and quantify the contribution of forest restoration to wind erosion control. Results showed that forest cover increased significantly from 3.95% to 36.19% over the past 40 years, with expansion primarily concentrated in the central desertified regions and the northern hilly areas. Sand fixation increased from $8.70\times {10}^5$ t to $8.20\times {10}^6$ t, with an average annual growth of $9.06\times {10}^4$ t/year. Spatially, growth rates were more pronounced in the central and northern regions than in the south. Ecological restoration programs contributed substantially to wind erosion control, with their attributable sand fixation increasing from near zero to $6.61\times {10}^5$ t, with an average annual rate of $8.21\times {10}^3$ t/year. These findings provide new insights into the role of large-scale forest restoration in enhancing sand fixation and mitigating wind erosion.