The grassland ecosystem accounts for 50.9% of the Qinghai-Tibet Plateau,which is a sensitive area of climate change and an ecologically fragile zone.It is an ideal place to study the response mechanism of grassland ecosystems to climate change.The sexual reproduction stage of plants is very sensitive to the small variation in environmental conditions.The response mechanism of alpine plant growth and reproduction strategies to global warming is still unrevealed.In order to explore reproduction strategies of alpine plants to adapt to global warming and guide the prediction of the trend of alpine vegetation communities,in this study,a simulated warming experiment was set up using the Open-Top Chambers(OTCs)- type device to explore the effect of warming on the sexual reproduction characteristics of apline representative plants: Kobresia humilis,Carex moorcroftii,and Elymus nutans.The results showed that:1)The numbers of reproductive shoots and the reproductive efficiency of Kobresia humilis significantly decreased(P<0.01); The effective spikelets length of Carex moorcroftii increased significantly(P<0.05),and the length of Elymus nutans spikelets increased significantly under the warming (P<0.01).2)Simulated warming caused a significant decrease in seed production capacity of Kobresia humilis (P<0.01)and Elymus nutans (P<0.05),and there was no significant difference in seed yield of Carex moorcroftii (P>0.05).3)The germination potential of three plants significantly decreased under the increase of temperature(P<0.05), but the germination rate did not change significantly(P>0.05).4)According to the heatmap analysis,under the influence of temperature increase,each index of Kobresiahumilishad highly negative responses to the warming effect.It is expected that the grassland with Kobresia humilis as the dominant vegetation would have the highest inhibitory degree of sexual reproduction under the effect of warming.In summary, under the climate warming,different plants showed different adaptation strategies.The sexual reproduction of Kobresia humilis was inhibited,and the response to warming was the most sensitive.