The impact of plateau pikas (Ochotona curzoniae) on alpine grassland vegetation and soil is not uniform within the home range of pika families

Background: Plateau pika (Ochotona curzoniae) is a small lagomorph mammal, common in alpine meadows. Previous studies show that pika activity is not uniform within a home range of a pika family. However, whether such small-scale differences in pika activities induce spatial patterns of soil and vegetation parameters is unclear. Aims: Our aim was to examine if the impact of pikas on the vegetation and soil was uniform within a pika family’s home range. Methods: Vegetation and soil were sampled in eight individual pika family’s home ranges and control areas. We divided each pika home range into three areas that differed in pika activity, the highest activity being in the central of the home range, declining further away from the central. Results: Vegetation cover, vegetation height, above-ground biomass the abundance of graminoids, root biomass, soil moisture, NO3-N, soil organic carbon, the soil pH,soil bulk density and NH4-N showed a clear pattern that correlated with pika activity levels. However, other soil nutrients showed no clear patterns. Conclusion: Because individual pika families do notuse their home ranges uniformly, their spatial pattern of activity intensity within a home range induce a spatial patchiness in boththe vegetation and the soil.