短期增温及氮沉降对青藏高原高寒草甸土壤呼吸的影响

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中图分类号：S812.2 文献标识码：A 文章编号：1007-0435（2025）05-1445-1：

Abstract： Global climate warming and nitrogen deposition willchange the carbon exchange between grassland ecosystem and atmosphere. However，the response of soil respiration rate and its components to warming and nitrogendeposition in alpine meadows on the Qinghai-Tibet Plateau is unclear. Therefore，this study conducted different levels of warming[ W0 （did not increase temperature）， W1 （air temperature increased by 0.47∘C ，soil temperature increased by 0.61∘C ）， W2 （air temperature increased by 0.92∘C ，soil temperature increased by 1.09∘C ）， W3 （air temperature increased by 1.44∘C ，soil temperature increased by 1.95∘C and nitrogen deposition ！ N16 （ ， experiments in the alpine meadow of the Qinghai-Tibet Plateau.The effects of biotic and abiotic factors on soil respiration and its components under warming and nitrogen deposition were clarified. The results showed that compared with W0 ，soil respiration and its components increased significantly under W3 treatment. Soil temperature and soil N/P ratio under shortterm warming and nitrogen deposition were the key factors affecting soil respiration and soil heterotrophic respiration.Soil autotrophic respiration is afected by soil ammonium nitrogen，soil temperature，soil nitrate nitrogen and plant Shannon-Wiener index. Combined with the above results，warming and nitrogen deposition will change soil physical and chemical properties and plant community characteristics，and then affectthe soil respiration rate and its components of alpine meadow ecosystem.

Key Words：Nitrogen deposition; Warming;Soil respiration rate;Soil heterotrophic respiration;Soil autotrophic respiration;Biological factors;Abiotic factors

土壤呼吸作为陆地生态系统与大气之间最大的碳通量之一，其所释放的二氧化碳量大约是人为化石燃料燃烧排放量的10倍，占年大气二氧化碳年总输人的 20%～40%（1] 。（剩余22560字）