关键词: 高寒草甸, 高原鼠兔, 草地退化, 鼠类防控, 灭鼠时间, 群落结构

Abstract: The effects of plateau pika on grassland ecosystems have received much attention,while the effects of multi-year pika eradication on its population size dynamics and plant community structure are less investigated. In this study,we eradicated the plateau pika within nine consecutive years and three times per year in alpine meadows seriously impacted by plateau pika in Henan County,Qinghai Province,to study the effects of multi-year pika eradication on the plateau pika population size and plant community structure. The results showed that plateau pika population density decreased rapidly in the first four years,while did not change obviously in the last five years. Plant community cover,height and above-ground biomass increased significantly with eradication time,and were negatively correlated with the plateau pika population density,which indicated that high density pika population size was detrimental to the maintenance of plant cover and aboveground biomass. The influnce of climatic factors on the above-ground biomass of plants was stronger than pika population size,and its influence on pika population size was also stronger than the time of eradication. Therefore,for alpine meadows with severe rodent infestation,rodent eradication synergizing with climatic factors influenced the size of plateau pika population and the structure and function of plant communities.

Key words: Alpine meadow, Plateau pika, Grassland degradation, Rodent eradication, Rodent eradication time, Community structure