中文摘要：

为把握森林土壤温度及土壤异养呼吸对气候变暖的响应,利用1986—2013年哀牢山亚热带常绿阔叶林土壤温度观测数据模拟土壤温度未来上升2℃需要的时间,采用2011—2013年人工控制土壤增温试验中切根处理（NR）与切根增温处理（SW）的观测数据,结合WNMM模型及SRES情景下A2与B2未来气候数据模拟哀牢山森林土壤异养呼吸对气候变暖的响应。结果表明：5 cm土壤温度增加速率为0.224℃·10 a^-1,自然增温2℃需要90 a;NR与SW处理下土壤Q（10）值分别为5.17和4.50,根据Q（10）值进行计算,NR处理在土温升高2℃后土壤异养呼吸较SW处理实测值升高14.6%;经过校正、验证后WNMM模型可以模拟土壤水分（P〈0.001）与土壤温度的变化（P〈0.001）;A2、B2情景下,NR处理土壤异养呼吸较SW处理分别升高10.2%和9.8%;A2情景下土壤异养呼吸较B2情景下土壤异养呼吸,在NR、SW处理下分别升高7.0%和6.6%。本研究中数学模拟会高估土壤异养呼吸,表明野外的实测试验是不可替代的评估土壤异养呼吸对气候变暖响应的方法。

英文摘要：

To improve our understanding of the responses of soil temperature and soil heterotrophic respiration to global warming in forest ecosystem, we simulated the change trend of soil temperature of subtropical evergreen broadleaved forest in Ailao Mountains using the observed soil temperature data from 1986 to 2013, and computed the time required for a 2 ℃ increase in soil temperature. We conducted a soil warming experiment in a subtropical evergreen broadleaved forest in Ailao Mountains. We compared field observations from trenching （NR） and trenching with soil warming （SW） from 2011 to 2013 with simulation results obtained from the WNMM model using future climate data under SRES A2 and B2 scenarios. We found that the soil temperature at 5 cm depth was significantly increased by 0.224 ℃·10 a-1 in the last 30 years, and thus it would spend 90 years to increase 2 ℃. The apparent respiration temperature sensitivity index （Q10） was 5.17 and 4.50 under the NR and SW treatments, respectively. Based on the Q10 value, under a 2 ℃ increase in soil temperature, soil heterotrophic respiration under the NR treatment was 14.6% higher than that of the SW treatment. The WNMM model was able to simulate soil water content （P〈0.001） and soil temperature （P〈0.001） after calibration and validation. By the end of 2100, soil heterotrophic respiration under the NR treatment would be 10.2% and 9.8% higher than that under the SW treatment under SRES A2 and B2 scenarios, respectively, and the soil heterotrophic respiration under the NR and SW treatments would be 7.0% and 6.6% higher under the SRES A2 scenario than under the SRES B2 scenario, respectively. These results indicated that field experiments on soil warming were important for understanding the responses of soil heterotrophic respiration to global warming, and should not be replaced by model simulation in that the latter will overestimate soil heterotrophic respiration.