青藏高原高寒草甸不同海拔梯度上增温和优势植物物种去除对生态系统碳通量的影响

生长季的GEP值比ER高, 表明这两个生态系统在生长季表现为碳汇。在低海拔地区, 增温对生态系统C通量没有显著的作用, 原因可能是增温导致的水分限制。在较湿润的高海拔地区, 生态系统C通量对增温产生积极的响应, GEP的相对增加量高于ER, 导致NEE增加。优势植物物种的去除对两个海拔的生态系统C通量均没有显著的作用。增温和优势物种去除对生态系统C通量也没有显著的交互作用。本研究结果将加深我们对青藏高原高寒草甸生态系统碳通量对气候变化和人类活动综合响应的理解。致谢 感谢中国科学院西北高原生物研究所在野外研究期间给予的支持。感谢北京大学城市与环境学院博士研究生徐炜以及硕士研究生张立旭和张智起在野外实验中给予的帮助。

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