青藏高原川西云杉林生物量对气候变化的响应

Responses of Chuanxi spruce forest biomass to climate change on the Tibetan Plateau

近几十年来,剧烈的气候变化已严重影响到青藏高原森林生态系统的结构和功能,青藏高原逐渐成为研究森林对气候变化响应的热点地区。本研究以分布于青藏高原地区的川西云杉(Picea likiangensis var.rubescens)为例,应用森林生态系统过程模型,设置4种气候变化预案,模拟不同气候变化情景下不同海拔和不同林分年龄阶段的川西云杉林生物量动态变化,通过比较不同气候变化情景下生物量的变化率来量化川西云杉林生物量对气候变化响应的强烈程度。结果表明:气候变暖会促进川西云杉林生物量增加,且生物量增幅与气候变暖的程度呈正相关(P<0.05);随着海拔升高,川西云杉林生物量对气候变化的响应程度增强;从短期和中期来看,川西云杉幼龄林生物量表现出对气候变化的响应强烈,但从长期来看,川西云杉中龄林生物量对气候变化的响应强烈。

Drastic climate change over past decades has seriously affected the structure and function of forest ecosystems,making Tibetan Plateau one of the hotspots for exploring the response of forest to climate change.In this study,we used a forest ecosystem process model and set up four simulation scenarios to simulate the dynamics of Chuanxi spruce(Picea likiangensis var.rubescens)forest biomass at different elevations and different stand ages under various climate change scenarios.The variation rates of biomass among different climate change scenarios were used to quantify the response intensity of Chuanxi spruce forest biomass to climate change.The results showed that future climate warming would increase Chuanxi spruce forest biomass and that the increment in biomass was positively correlated with the magnitude of climate warming(P<0.05).With the increases of elevation,the response of biomass to climate change showed an increasing trend.In the short-and mid-term,the biomass of young forests showed the stronger response to climate change;but in the long-term,the biomass of middle-aged forests showed the stronger response to climate change.