【摘要】 通过室内模拟试验，分析寒温带典型森林土壤有机碳矿化随温度和水分的变化特征，揭示土壤有机碳矿化影响机制，以期深入探讨气候变暖背景下，温度和水分对寒温带典型森林类型土壤碳循环的影响。采集白桦林和兴安落叶松林0<h≤10 cm和10 cm<h≤20 cm土层土壤（h）,设计3个温度梯度（10、15、20℃）和3个水分梯度（30%、45%和60%）进行土壤碳矿化室内培养试验。结果表明：（1）两种林型0<h≤20 cm土层土壤有机碳矿化速率均呈明显的单峰曲线变化趋势，峰值出现在培养后的4～6 d,白桦林土壤有机碳矿化速率峰值波动在13.38～77.47 mg·kg^-1·h^-1,兴安落叶松林峰值波动在10.82～48.08 mg·kg^-1·h^-1,白桦林土壤有机碳矿化速率高于兴安落叶松林，随培养时间延长矿化速率迅速降低，并趋于平缓；（2）两种林型土壤矿化速率和累积矿化量与温度和水分呈显著正相关。白桦林土壤有机碳矿化速率和累积矿化量在不同土层均高于兴安落叶松林，0<h≤10 cm土层，白桦林在20℃培养时，3个水分梯度下的累积矿化量分别是兴安落叶松林的1.27、1.01、1.19倍，10 cm<h≤20 cm土层分别是1.24、1.40、1.26倍；（3）两种林型土壤在温度从10℃升高到20℃时，温度敏感性(Q₁₀)随水分增加而增加，且10 cm<h≤20 cm土层Q₁₀值高于0<h≤10 cm土层。寒温带典型森林类型土壤有机碳矿化受温度和水分的显著影响，土壤有机碳矿化速率随温度升高而加快，并伴随着森林碳排放量的增加。更多还原

【Abstract】 Through indoor simulation experiments, we analyzed the characteristics of soil organic carbon mineralization in typical forest types of the cold temperate zone with changes in temperature and moisture, to reveal the influencing mechanisms of soil organic carbon mineralization. The aim was to further explore the effects of temperature and moisture on soil carbon cycling in typical forest types of the cold temperate zone under the background of climate warming. Soil samples were collected from the 0<h≤10 cm and 10 cm<h≤20 cm layers of Betula platyphylla and Larix gmelinii forests. We designed three temperature gradients（10, 15, and 20 ℃） and three moisture gradients（30%, 45%, and 60% water content） for indoor soil carbon mineralization incubation experiments. The results showed that:（1） The organic carbon mineralization rates of soils in both forest types at the 0<h≤20 cm layer exhibited a significant unimodal trend, with peaks occurring at 4-6 days of incubation. The peak values of organic carbon mineralization rates in B. platyphylla forests fluctuated between 13.38-77.47 mg·kg^-1·h^-1, while in L. gmelinii forests they fluctuated between 10.82-48.08 mg·kg^-1·h^-1. The organic carbon mineralization rate in B. platyphylla forests was higher than in L. gmelinii forests, and decreased rapidly with extended incubation time, eventually leveling off.（2） The mineralization rates and cumulative mineralization amounts of soils in both forest types were positively correlated with temperature and moisture. The organic carbon mineralization rate and cumulative mineralization amount in B. platyphylla forests were higher than in L. gmelinii forests across different soil layers. In the 0<h≤10 cm layer, the cumulative mineralization amounts in B. platyphylla forests at 20 ℃ incubation were 1.27, 1.01, and 1.19 times those of L. gmelinii forests at the three moisture gradients, respectively, while in the 10 cm<h≤20 cm layer, they were 1.24, 1.40, and 1.26 times higher.（3） The Q₁₀ values of soil in both forest types increased with increasing moisture when temperatures rose from 10 ℃ to 20 ℃, with the Q₁₀ values in the 10 cm<h≤20 cm layer being higher than in the 0<h≤10 cm layer. Soil organic carbon mineralization in typical forest types of the cold temperate zone is significantly influenced by temperature and moisture, with soil organic carbon mineralization rates accelerating with increasing temperature, leading to increased forest carbon emissions.更多还原