Linking density of plateau pika to vegetation characteristics and soil attributes in response to different grazing regimes

With changes in climate conditions and land use, the increase in the density of plateau pika (Ochotona curzoniae) challenges the sustainable management of alpine rangelands on the Qinghai-Tibet Plateau. Plateau pikas can affect grassland vegetation and soil properties. However, there is a lack of knowledge about the associations between plateau pika, vegetation, and soil in response to different grazing regimes (e.g. single-household vs. multi-household pastures). In this study, we worked at three sites in the alpine rangelands on the eastern Qinghai-Tibet Plateau to compare the density of plateau pika burrows, vegetation characteristics, soil properties, and their associations with single-household versus multi-household pastures. Compared to those of single-household pastures, the multi-household pastures were characterized by lower density of plateau pika burrows and less soil nutrients but taller vegetation. There were nonsignificant differences in vegetation cover, plant species richness, soil organic matter, soil pH, and humidity between single-household and multi-household pastures (P > 0.05). In single- and multi-household pastures and overall sites, the density of plateau pika burrows significantly negatively correlated with the vegetation height and plant species richness (P < 0.05), but positively correlated with soil pH and available nitrogen. In sum, multi-household grazing potentially depresses the outbreak of plateau pika by increasing vegetation height and plant diversity.