Abstract. The activity of small mammalian herbivores influences grassland ecosystem services in arid and semi-arid regions. Plateau pika (Ochotona curzoniae) was considered to be a focal organism to investigate the effect of small mammalian herbivores on meadow ecosystem services in alpine regions. In this study, a home-range scale was used to measure the forage available to livestock, water conservation, carbon sequestration and soil nutrient maintenance (total nitrogen, phosphorus and potassium) in the topsoil layer, and a quadrat scale was used to assess the biodiversity conservation of alpine meadows. This study showed that the forage available to livestock and water conservation was 19 % and 16 % lower in the presence of plateau pikas than in their absence, and biodiversity conservation, carbon sequestration, soil nitrogen and phosphorus maintenance was 15 %, 29 %, 10 % and 8.9 % higher in the presence of plateau pikas than in their absence. In contrast, it had no impact on soil potassium maintenance of meadow ecosystems in alpine regions. The forage available to livestock, biodiversity conservation and soil nutrient maintenance of meadow ecosystems in alpine regions had maximum values as the disturbance intensity of plateau pikas increased; the water conservation tended to decrease linearly with the increasing disturbance intensity of plateau pikas. These results present a pattern of plateau pikas influencing the ecosystem services of meadow ecosystems in alpine regions, enriching our understanding of the small mammalian herbivores in relation to grassland ecosystem service.

No abstract

Herbivore disturbance can affect the grassland ecosystem services though creating extensive disturbances vegetation and soil. This study focused on plateau pika (Ochotona curzoniae) disturbance to investigate the effect of disturbance by small burrowing herbivores on ecosystem services of alpine grasslands though five sites. In this study, the palatable plant biomass, plant species richness, soil water storage, soil organic carbon, total nitrogen, phosphorus and potassium stocks were used to estimate the forage availability, biodiversity conservation, water conservation, carbon sequestration and soil nutrient maintenance. This study showed that plateau pika disturbance was related to higher plant species richness and soil organic carbon stock, associated with lower palatable plant biomass and soil water storage, and had no effect on total potassium stock, whereas the responses of soil total nitrogen and phosphorus stocks to plateau pika disturbance were different among sites. The palatable plant biomass, plant species richness, soil organic carbon, total nitrogen and phosphorus stocks showed downward parabolas, whereas the soil water storage showed a decreasing trend with increasing plateau pika disturbance intensity. These results indicated that the role of plateau pikas is dependent not only on the management target of alpine grasslands but also on the plateau pika disturbance intensity.