Small Semi-Fossorial Herbivores Affect the Allocation of Above- and Below-Ground Plant Biomass in Alpine Meadows

Abstract

Small semi-fossorial herbivores can affect plant aboveground biomass (AGB) in grasslands and possibly alter the allocation of AGB and belowground biomass (BGB). In this study, plateau pika (Ochotona curzoniae) was used to investigate such effects at three alpine meadow sites on the Eastern Tibetan Plateau, where pairs of disturbed vs. undisturbed plots were randomly selected and sampled. We also explored the relationships between soil properties and BGB/AGB across the plots in the presence and absence of plateau pikas, respectively. We found that BGB and BGB/AGB were 11.40 and 8.20% lower in the presence of plateau pikas than in their absence, respectively. We also found that the BGB/AGB was positively related to soil moisture and soil total nitrogen (STN) in the absence of plateau pikas. In contrast, BGB/AGB was positively related to STN, soil organic carbon (SOC), soil carbon/nitrogen (C/N), and soil total phosphorus in the presence of plateau pikas. These factors indicated plateau pika disturbance increased AGB allocation. The relationship between AGB and BGB of alpine meadow plants to soil variables was also different between sites with and without plateau pika disturbance. In conclusion, small semi-fossorial herbivore disturbance is likely to alter grassland carbon stock and should be well controlled for sustainable conservation and management of alpine meadows on the Tibetan Plateau.

Trait‐based mechanistic approach highlights global patterns and losses of herbivore biomass functional diversity

“…Less attention has been devoted to lighter (‘small’) terrestrial herbivorous mammals (body mass <~5–10 kg), in spite of their important influence on ecosystem function and structure (Bomske & Ahlers, 2021; Dickman, 1999). Small herbivores can change soil properties including moisture, carbon and nitrogen content through bioturbation (e.g., burrowing and soil redistribution), consumption and excretion, which can alter above and below‐ground plant biomass and in greenhouse gas emissions (Wang, Pang, & Guo, 2022; Wang, Sun, et al., 2022). Overall, the sphere of influence of small mammals appears comparable to larger animals as it includes nutrients, carbon cycling and greenhouse gas fluxes (Poe et al., 2019; Wang, Pang, & Guo, 2022; Wang, Sun, et al., 2022).…”

Plateau pika burrowing and yak grazing jointly determine ecosystem greenhouse gas emissions of alpine meadow

“…In alpine meadows, clipping and burrowing behaviour of plateau pika decreased aboveground biomass and plant height (Zhang et al, 2020), but significantly increased plant diversity, soil organic carbon, and soil nutrients (Pang et al, 2020; Yu et al, 2017). The changes in plant and soil properties can further affect the coupling and linkages between above and belowground of ecosystems (Wang et al, 2022). In the central grasslands of North America, the strong influences of domestic cattle ( Bos taurus ) and prairie dogs ( Cynomys spp.)…”