Title: The disturbance and disturbance intensity of small and semi-fossorial herbivores alter the belowground bud density of graminoids in alpine meadows

Authors: Qian Wang, Cheng Yu, Xiao Pan Pang, Shao Hong Jin, Jing Zhang, Zheng Gang Guo*

Journal: Ecological Engineering

Impact Factor:IF₂₀₁₆=2.914 (环境科学与生态学三区)

Abstract: Do semi-fossorial herbivores influence thetrajectory of plant community succession by altering belowground bud density in alpine meadows? Field surveys were carried out to investigate the effect of disturbance and disturbanceintensity of the plateau pika (Ochotona curzoniae) on the belowground bud density in alpine meadows at two sites. The linear mixed model (LMM) test and linear model (LM) test were used to analyze the relative effect of plateau pikadisturbance on bud density and to clarify the response of belowground bud density to disturbance intensity. Our results showed that disturbance bythe plateau pikaincreased belowground bud density of graminoids andplants from the grass and sedge families, includingKobresia pygmaea and Elymusnutans, but had no effect on forbs bud density. The bud density of graminoids, grassand sedge plants, and K. pygmaea and E.nutansshowed a downward parabolic trend in response to increaseddisturbance intensity of the plateau pika, implying thattherewas an optimal level of disturbance intensity thatmaximized belowground bud density of graminoids. These results suggest that disturbance bythe plateau pika has different effects on belowground bud densities of graminoids versus forbs.Additionally, disturbance by plateau pika up to the optimal intensity may improve grazing quality of alpine meadow in the long termthrough increasing graminoid bud density, resulting ina higher proportion of graminoids in pasture, while higher levels of disturbance by plateau pika may deteriorate alpine meadows through a reduction ingraminoid bud density.

链接: https://doi.org/10.1016/j.ecoleng.2018.01.003