Abstract: The northwest of Liaoning Province is a critical area in the battle against desertification in the Horqin Sandy Land. Assessing the wind reduction and sand fixation services is significant for regional ecological security and food security as well as the protection of black soil. In this study, we quantitatively evaluated the temporal and spatial variations of the services of wind reduction and sand fixation in the northwest of Liaoning from 2000 to 2020 based on the Revised Wind Erosion Equation (RWEQ) model and explored its driving factors. The results showed that: (1) From 2000 to 2020, the total amount of sand fixation increased from 13.09×10¹⁰ kg to 14.02×10¹⁰ kg, and the retention rate of sand fixation rose from 78.0% to 82.9%. Highvalue areas of sand fixation were mainly concentrated in the northwest of the study area, with a significant improvement in regional wind reduction and sand fixation capacity over the 20 years. (2) The retention rate of wind reduction and sand fixation across different land use types followed a pattern: woodland > grassland > cropland > other land > construction land > water bodies. Moreover, the wind reduction and sand fixation capacities of each ecosystem were improved during the past 20 years. Combined with land use change analysis, the expansion of woodland areas and the stable and positive development trend of ecosystems were the primary driving forces for the improvement of regional wind reduction and sand fixation capacity. (3) Wind speed was the main driving factor causing changes in the wind reduction and sand fixation service function in the northwest of Liaoning, whereas precipitation had a moderate impact. Over the past 20 years, an increase in vegetation coverage indicated good regional vegetation restoration, which was a key factor in enhancing wind reduction and sand fixation in the sandy control areas of northwestern Liaoning.

Key words: northwestern Liaoning Province, wind reduction and sand fixation, retention rate of wind reduction and sand fixation services, driving factor