Abstract:

The Hulunbuir Leymus chinensis Meadow Grassland is a grassland formation at the eastern end of the Central Asian Grassland Subregion in the Eurasian Grassland Region. It is one of the representative types of meadow grasslands, and its grassland ecosystem is undergoing dual pressures from human interference such as grazing and climate change, resulting in varying degrees of degradation. Based on the correlation between grazing disturbance intensity and grassland biomass, this paper selected the natural Leymus chinensis meadow inside and outside the fence in Hulunbeier area to carry out long-term observation on the composition of plant community in the field (enclosed in 2005), obtained the composition data of plant community in the meadow grassland (2009-2015), and studied the response of community coverage, community abundance, and community height to grazing intensity on this basis. Research has shown that enclosure significantly increases the aboveground biomass of grasslands, and the degree of improvement is positively correlated with the duration of enclosure; Meanwhile, moderate grazing interference will not cause a decrease in the abundance of grassland communities. Among them, the latter conclusion has enlightening significance for the grassland ecological compensation mechanism currently aimed at balancing grassland ecological protection and productivity improvement. Proper enclosure and grazing prohibition in severely degraded areas can help protect and build grasslands, partially reflecting the necessity of ecological compensation. At the same time, further analysis also indicates that there is still room for exploration in optimizing relevant policies. This study helps to deepen the understanding of grazing response and feedback mechanisms in grassland ecosystems, and can provide scientific basis for the protection and sustainable utilization of grassland ecosystems.

Key words: Hulun Buir, enclosed grassland, natural grassland, community biomass