Abstract: [Objective] To better understand how dominant plants' leaf nutrient content and stoichiometric characteristics respond to varying grazing intensities in the desert steppe. [Method] On the grazing sample plots of Stipa breviflora desert steppe in Inner Mongolia, four treatments with varied grazing intensities were set up: control （CK）, light grazing （LG）, moderate grazing （MG）, and heavy grazing （HG）, with stocking rates of 0, 0.91, 1.82, and 2.71 sheep/hm² respectively. In the year of 2020, under varying grazing intensities, the concentrations of C, N, and P in leaves of domoinant plants Stipa breviflora, Cleistogenes songorica, Convolvulus ammannii and Artemisia frigida were measured, and their stoichiometric properties were calculated.[Result] Compare with CK group, heavy grazing significantly （P<0.05） decreased the leaf C concentration of Stipa breviflora and Convolvulus ammannii. Grazing had no significant （P>0.05） effect on the leaf N content of all four dominant plants tested. Moderate grazing significantly （P<0.05） increased the P concentration in the leaves of Stipa breviflora and Convolvulus ammannii, while significantly （P<0.05） decreased the P concentration of Artemisia frigida. Heave grazing significantly （P<0.05） decreased the C∶N of Convolvulus ammannii, the C∶P of Stipa breviflora, Convolvulus ammannii and Artemisia frigida as well as the N∶P of Stipa breviflora. [Conclusion] Grazing alters plants' nutrient utilization. Different plants have different adaptation strategies to the same habitat. Grazing reduces the C fixation capacity of dominant plants in desert steppe. Long-term moderate grazing promotes the absorption of N and P by dominating plants in desert steppe.

Key words: desert steppe, dominant plants, stocking rates, ecological stoichiometry