Grazing is a primary utilization method of grasslands， and determining the appropriate grazing intensity is of crucial for grassland conservation and the sustainable development of animal husbandry. A controlled grazing experiment was conducted during the warm season of 2023 at the 77th Regiment Horse Farm in Zhaosu County， four treatments were set up： no grazing， light grazing （1 horse·hm^-2）， heavy grazing （4 horse·hm^-2）， and extreme grazing （6 horse·hm^-2）， and a randomized block design was adopted. The effects of grazing intensity on pasture carrying capacity were evaluated by monitoring plant community structure， diversity， standing biomass， forage nutritional quality， and by calculating digestible energy （DE） and the grading index 2001 （GI₂₀₀₁）.The results indicated that light grazing maintained relatively a high species diversity， while the no-grazing area exhibited the best forage nutritional quality. The biomass carrying capacity was the highest under heavy grazing [0.73 horse·hm^-2·（122d）^-1]， and the crude protein yield carrying capacity was relatively high under extreme grazing [0.99 horse·hm^-2·（122d）^-1]. However， these conditions were accompanied by the decline of sedges and a surge in forbs， representing an unsustainable short-term phenomenon. The PLS-PM （Partial Least Squares Path Modeling） model showed a direct negative effect of grazing intensity on GI₂₀₀₁ and DE. In conclusion， light grazing （1 horse·hm^-2） is the suitable intensity for the Zhaosu mountain meadow steppe， effectively balancing ecological conservation and the needs for continuous grazing of Yili horses.

Grazing intensity  /  Mountain meadow grassland  /  Forage nutritional quality  /  Forage digestible energy  /  Vegetation characteristics