Alpine Steppe Vegetation Communities Are More Sensitive to Plateau Pika Disturbance Than Alpine Meadows

Rui Hua^1*Peng Zhang²Liqing Wang²Miaomiao Huang³Limin Hua³Zhou Jainwei^1*

• ¹Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, Inner Mongolia Autonomous Region, China
• ²Monitoring and planning Institute of Inner Mongolia forestry and grassland administration, Hohhot, China
• ³Gansu Agricultural University, Lanzhou, Gansu Province, China

Small herbivores are important biological factors affecting plant productivity and species richness in the grassland ecosystem of the Tibetan Plateau. However, the response of different grassland types to the disturbance of the "endemic species" plateau pika (Ochotona curzoniae) remains unclear. In this study, two representative grassland types, alpine meadow and alpine steppe, were taken as research objects to compare the effects of pika disturbance on vegetation structure and function indicators, and to explore the disturbance response threshold of these ecosystems. The results showed that the alpine steppe was more sensitive to pika disturbance, and its biomass, vegetation height and coverage decreased significantly even at low disturbance levels. In contrast, alpine meadows showed greater resilience and maintained higher productivity and species diversity under moderate disturbance conditions. It is worth noting that the function index of alpine meadow peak is in a moderately disturbed state, while alpine steppe is rapidly transitioned to a degraded state. These differences highlight the different disturbance thresholds between the two grassland types. This study highlights the vulnerability of alpine grassland ecosystems to pika disturbance, and provides a strong scientific basis for designing effective grassland management and ecological restoration strategies.