Plateau pika disturbances alter plant productivity and soil nutrients in alpine meadows of the Qinghai-Tibetan Plateau, China

Abstract

Plateau pika (Ochotona curzoniae) is an endemic mammal in the Qinghai-Tibetan Plateau, and its activities create extensive disturbances on vegetation and soil of alpine meadow. Field surveys at two sites were conducted to determine the effects of plateau pika disturbances on important soil factors and plant biomass of vegetated land, and their relationships of the same alpine meadow type. Our study showed that plateau pika disturbances significantly increased soil organic carbon, soil total nitrogen, graminoid biomass and the number of plant species, and significantly decreased soil moisture and forb biomass, although they had no significant impacts on soil total phosphorus, soil total potassium and total biomass on vegetated land. Our study further showed that soil organic carbon, soil total nitrogen, graminoid biomass and the number of plant species were much higher at intermediate disturbance intensities than those at low and high disturbance intensities in the disturbed areas, and soil moisture showed a decreasing trend with the increase of disturbance intensity. Plateau pika disturbances altered the contribution of some important soil nutrients and moisture to plant biomass, and had different impact on the best models between plant biomass (total biomass, graminoid biomass and forb biomass) and predominant soil factors. Our results demonstrated that the optimal disturbance intensities of plateau pika were beneficial to alpine meadow. These results highlighted the influence of the presence of plateau pika and its disturbance intensity on key soil nutrients and plant productivity on vegetated land of the same alpine meadow type, which will help us better understand the role of plateau pika in the alpine meadow ecosystem.

Global meta‐analysis of soil‐disturbing vertebrates reveals strong effects on ecosystem patterns and processes

“…It is now well established that overgrazing was the main cause of the degradation, and the degraded state provided favourable conditions for pikas and zokors (Zhang et al, ). There is mounting evidence that plateau pikas facilitate nutrient cycling and grass productivity through burrowing, although these effects are dependent on population density (Pang & Guo, ; Yu, Pang, Wang, Jin, & Shu, ). Given their important role in ecosystems, we would expect the loss of ecosystem engineers such as pikas to have substantial consequences for ecosystem functioning (Fleming, Anderson, Prendergast, Bretz, & Valentine, ).…”

Functional‐trait ecology of the plateau pika Ochotona curzoniae in the Qinghai–Tibetan Plateau ecosystem

“…The results of studies relating this biopedturbation (Whitford & Kay 1999) to the influence of plateau pikas on plant species richness have been mixed. Liu et al (2013) and Sun et al (2015) indicate that plant species richness decreases with increasing pika density, whereas Bagchi et al (2006), Hogan (2010), Liu et al (2012) and Pang and Guo (2017) found that plant species richness was higher inside pika colonies (areas with demonstrable biopedturbation) compared with undisturbed areas devoid of pikas. A primary reason for this discrepancy concerns the scale at which measurements were taken.…”

“…This uppermost soil horizon "may have a thickness of a few centimeters to a couple of decimeters and appears to consist mainly of felty remains of living and dead fine roots … The turfs are ex- Studies that take a landscape-scale approach, however, generally find that pikas increase plant species richness. Bagchi et al (2006), Hogan (2010), Liu et al (2012) and Pang and Guo (2017) established study areas with similar physiognomy on the alpine meadow, but contrasted disturbed (biopedturbation = active pika colony) sites versus sites where pikas were absent. The most robust of these studies ( Fig.…”

An evaluation of government‐recommended stocking systems for sustaining pastoral businesses and ecosystems of the Alpine Meadows of the Qinghai‐Tibetan Plateau

“…Here plant species richness has declined, unpalatable, and poisonous plants have increased as has “accelerated” soil erosion (Wang, Dong, et al., ; Wang, Lassoie, et al., ). Harris (), however, argues that “causes of degradation remain uncertain, often because hypotheses have been articulated too vaguely to test.” Causes for degradation are variously attributed; increased rainfall variability from climate change (Chen et al., ; Lehnert, Wesche, Trachte, Reudenbach, & Bendix, ), high localized herbivory, and soil disturbance from Plateau Pika ( Ochotona curzoniae ) and Plateau Zokor ( Myospalax baileyi ) (Harris, Wang, Smith, & Bedunah, ; Pang & Guo, ; Smith & Foggin, ), road building (Qiu, ) and increased domestic stock numbers (Hao, ; Qiu, ).…”

“…The degradation of the QTP grassland of the QTP, especially of the nonmeadow grasslands, rose from 24.5% in 1980 to 34.5% in 1990 (Li et al., ). It was commonly believed that the degradation predisposed an increase in Plateau Zokor and Pika populations (Kang, Han, Zhang, & Sun, ) but this has been challenged (Pang & Guo, ; Pech, Arthur, Zhang, & Lin, ).…”