【摘要】 明晰未来气候变化情景下不同类型生态系统生产功能面临的风险,对因地制宜地采取气候变化适应措施具有重要的现实意义。目前从阈值识别角度对生态系统风险进行评价的研究还较少。该研究提出一种基于阈值识别的气候变化下生态系统风险分析的方法。基于气候、土壤和植被数据,运用大气-植被相互作用模型对1961—2080年北方农牧交错带的生态系统净初级生产力进行模拟,根据气候变化对不同类型生态系统净初级生产力的影响定义了"危险的影响"和"不能接受的影响"两类阈值,并根据生态系统净初级生产力在气候变化下的减少趋势与两类阈值的对比关系进行风险等级的划分,进而对未来气候变化下北方农牧交错带不同类型生态系统生产功能面临的风险进行了评估。结果表明:气候变化将给北方农牧交错带生态系统生产功能带来风险,以低风险为主。风险分布与未来气候变化密切相关,主要集中在西北地区北部、内蒙古地区东北部和东北地区中南部。风险范围随增温幅度的增加而扩展,到远期风险面积达到165.72×10~4 km~2,占研究区总面积的44.78%。混交林、稀树草原与荒漠草原较为危险;高寒草甸与常绿针叶林是较为安全的生态系统。农牧交错带核心区风险程度高于边缘区,揭示了其核心区在未来气候变化下趋于脆弱的趋势。更多还原

【Abstract】 It is helpful for decision-making on adaptation of climate change to illustrate risks of net primary production for ecosystem from climate change. The thresholds identification method has been documented little in previous studies. From the data of climate, soil texture and vegetation, Atmosphere Vegetation Interaction Model version 2 was employed to simulate the net primary production of ecosystem during the period of 1961—2080. Based on the definition of thresholds, we presented a new assessment method to detect the climate change risk on ecosystems. According to the climate change impacts on the net primary production of ecosystems, the ‘dangerous impact’ and the ‘unacceptable impact’ were defined as the thresholds. Compared with the ‘dangerous impact’ and the ‘unacceptable impact’, NPP loss in each grid was used to evaluate the risk on the ecosystems in farming-pastoral ecotone in northern China. The results showed that, climate change will bring risk on primary production of ecosystem in the study area, and the low risk will dominate the region. The risk distribution is likely to correlated with climate change in future, risk areas are likely to be concentrated on northern part of Northwest China, northeast part of Inner Mongolia, central and southern part of Northeast China. The risk areas would expand with the increase of warming degree. To the long-term, about 165.72 Mha ecosystems will face the risk on primary production, accounting for 44.78% of the total area. Temperate mixed forest, wooded savanna and desert grassland are likely to be more vulnerable than other ecosystems, while the alpine meadow and evergreen coniferous forest will be relatively safe. Risks in the core region of the farming-pastoral ecotone will intense than these in the marginal region, indicating the dangerous trend under the climate change.更多还原