高寒草地土壤温室气体排放对放牧的响应研究进展

Response of soil greenhouse gases emissions to grazing in alpine grasslands: a review

摘要:

高寒草地生态系统具有独特的地理环境和气候特征，对放牧干扰十分敏感，在全球温室气体通量中贡献突出，研究高寒草地放牧对土壤温室气体排放的影响机制具有重要意义。本文总结高寒草地温室气体源/汇特征、不同放牧方式对土壤微环境和微生物群落结构的影响，发现高寒草地主要是CO₂源、CH₄汇、N₂O源。放牧通过家畜选择性采食、践踏和排泄物返还等多重机制作用于地上植物、土壤结构、温度、湿度和养分，进而影响地下微生物及温室气体通量。本文旨在为高寒草地生态系统健康发展和管理及缓解全球气候变化提供科学依据，并对未来研究方向进行展望。

Abstract:

Due to the unique geographical environment and climate characteristics, the alpine grassland ecosystem is sensitive to grazing perturbation, contributing greatly to global greenhouse gases (GHGs) emissions. Therefore, it is significant to decipher the effect of grazing on GHGs emissions in alpine grassland. This study summarized the switch of GHGs sources or sinks and the response of soil microenvironment and microbial community structure under different grazing methods in alpine grassland. It is concluded that alpine grassland is the major CO₂ source, CH₄ sink, and N₂O source. Besides, grazing directly affects the aboveground plant, soil structure, temperature, humidity, and nutrient contents through selective feeding, trampling, and excreta returning of livestock, and then indirectly affects soil microorganisms and GHGs fluxes. This review provides a novel perspective for the healthy development and management of the alpine grassland ecosystem, the mitigation of global climate change in the alpine grassland.