Abstract Anthropogenic activities have caused rapid warming globally, particularly in the alpine regions. The Tibetan Plateau is sensitive to global change and plays an important role in global carbon cycle due to its large area and high carbon density. Although a large number of field manipulative warming experiments have been conducted on the Tibetan Plateau, the general patterns of how warming affects ecosystem carbon (C) and nitrogen (N) cycles remain unclear. Here we conducted a meta-analysis from 65 publications to synthesize the responses of C and N cycles to warming in the alpine grassland ecosystems across the Tibetan Plateau. The results showed that warming significantly increased aboveground (mean 11.0%, 95% CI 1.6–21.4%) and belowground plant biomass (24.3%, 13.7–36.0%), soil dissolved organic C (13.6%, 5.4–22.5%), soil respiration (14.3%, 2.9–27.1%), ecosystem respiration (15.3%, 4.7–27.1%), and soil ammonium N (29.0%, 4.6–59.2%), but did not change soil total organic C (2.4%, −4.4 to 9.7%), soil total N (1.9%, −2.7 to 6.7%), microbial biomass C (5.5%, −4.1 to 16.2%) and microbial biomass N (4.7%, −7.4 to 18.4%). There were negative relationships between the response ratio of aboveground (P = 0.08, R2 = 0.05) and particularly belowground (P

中文翻译：

---

变暖对青藏高原高寒草地生态系统碳氮循环的影响：荟萃分析

摘要 人为活动导致全球迅速变暖，特别是在高寒地区。青藏高原面积大、碳密度高，对全球变化敏感，在全球碳循环中发挥着重要作用。尽管已经在青藏高原进行了大量的现场操纵变暖实验，但变暖如何影响生态系统碳（C）和氮（N）循环的一般模式仍不清楚。在这里，我们对 65 份出版物进行了荟萃分析，以综合 C 和 N 循环对青藏高原高寒草地生态系统变暖的响应。结果表明，变暖显着增加了地上（平均 11.0%，95% CI 1.6-21.4%）和地下植物生物量（24.3%，13.7-36.0%），土壤溶解有机碳（13.6%，5.4-22.5%），土壤呼吸 (14. 3%, 2.9–27.1%)、生态系统呼吸 (15.3%, 4.7–27.1%) 和土壤铵态氮 (29.0%, 4.6–59.2%)，但没有改变土壤总有机碳 (2.4%, -4.4 to 9.7%)、土壤总氮 (1.9%, -2.7 to 6.7%), 微生物生物量 C (5.5%, -4.1 to 16.2%) 和微生物生物量 N (4.7%, -7.4 to 18.4%)。地上（P = 0.08，R2 = 0.05）和地下（P