关键词: 荒漠草原, 土壤风蚀, 放牧强度, RWEQ模型

Abstract: Wind erosion is one of the major ecological and environmental problems in the arid and semi-arid steppe areas of northern China， which not only affects the stability of steppe ecosystems， but also exacerbates the problems of land degradation and desertification， and is a key factor affecting agricultural production and ecological security in the region. In this study， different grazing gradients were selected to investigate the relationship between grazing intensity and wind-sand flux and wind-erosion influencing factors， and to optimize the predictive ability of wind-erosion model. This experiment was carried out in a desert steppe grazing trial site through 4 treatments of control （CK）， light grazing （LG）， moderate grazing （MG） and heavy grazing （HG）， by the randomized block design with three replications. Based on the observations of wind and sand fluxes and wind erosion influence factor indicators of different grazing gradients in 2021-2022， some empirical parameters in the RWEQ model were calibrated and the calculation method of critical sand initiation wind speed was optimized. The results showed that the optimized RWEQ had a good fit between the predicted and measured wind-sand fluxes under different grazing intensities in 2022 with d=0.67， and R² of 0.9365， P<0.01， and the correlation between the predicted and measured wind-sand fluxes was good. The predicted results of the optimized RWEQ in the experimental area of different grazing intensities in desert steppe have a greater reference value for formulating reasonable grazing intensities， planning grazing time， guiding vegetation restoration， and assessing the impacts of grazing on ecosystem health.

Key words: Desert steppe, soil wind erosion, grazing intensity, RWEQ model