Effect of plateau pika presence on the ecosystem services of alpine meadows

Abstract. The activity of small mammalian herbivores influences grassland ecosystem services in arid and semi-arid regions. This study took plateau pika (Ochotona curzoniae) as example animal to investigate the effect of small mammalian herbivores on meadow ecosystem services in alpine regions. In this study, a home-range scale was used measure the forage availability, water conservation, carbon sequestration and soil nutrient maintenance services (total nitrogen, phosphorus, and potassium) of topsoil layer; and a quadrat scale was used to assess the biodiversity conservation service of alpine meadows. This study showed that plateau pika presence led to lower forage availability and water conservation services, and led to higher biodiversity conservation, carbon sequestration, soil nitrogen and phosphorus maintenance services of meadow ecosystem, whereas it had no impact on soil potassium maintenance service of meadow ecosystem in alpine regions. This study further found that the forage availability, biodiversity conservation, and soil nutrient maintenance services of meadow ecosystem in alpine regions firstly increased, and later decreased as the disturbance intensity of plateau pikas increased, whereas the water conservation service tended to decrease with the increasing disturbance intensity of plateau pikas. These results not only present a possible pattern of plateau pikas influencing the ecosystem services of meadow ecosystem in alpine regions, and consummate the small mammalian herbivores in relation to grassland ecosystem services.