Interannual Effects of Climate Factors on Community Characteristics of Different Vegetation Types in Ulanqab Steppe

With the gradual intensification of global climate change, the impact of climate factors such as temperature, precipitation, and wind speed on steppe communities is increasing. Exploring the effects of climate change on community characteristics of different vegetation types is of vital significance for studying steppe ecological processes, rational utilization and conservation of steppe resources, and the ecological restoration of degraded steppes. In this study, three climate factors, namely, annual average temperature, annual precipitation, and annual average wind speed, were investigated by using a plot survey method to analyze the interannual effects of different community characteristics of rhizome steppe, tussock steppe, shrubby/semi-shrubby steppe and forb steppe in Ulanqab grassland from 2010 to 2020. The following conclusions were drawn: (1) The annual average temperature, annual precipitation, and annual average wind speed exhibited a fluctuating increasing trend for the tussock and forb steppe; the annual mean temperature and annual mean precipitation of rhizome steppe and shrubby/semi-shrubby steppe showed a trend of increasing year by year, and the annual mean wind speed showed a trend of decreasing year by year. (2) The interannual changes of the 4 community characteristics of tussock steppe, rhizome steppe and forb steppe showed an overall trend of increasing year by year, while the interannual changes of the 4 community characteristics of shrubby/semi-shrubby steppe were not obvious. (3) Annual average temperature exerted the greatest influence on the characteristics of rhizome steppe and forb steppe communities, while it had no significant impact on the characteristics of shrubby/semi-shrubby steppe communities. Annual average wind speed had the most significant effect on the characteristics of the forb steppe community. Annual precipitation demonstrated a significant positive correlation with the characteristics of all four vegetation types, and its influence on the community characteristics of the Ulanqab Steppe region surpassed that of the annual average temperature and annual average wind speed, making it the primary climate factor impacting the community characteristics in this region.