The Influence of Temperature and Moisture to Soil Organic Carbon Mineralization in Typical Forest Types of the Cold Temperate Zone
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 cy-cling in typical forest types of the cold temperate zone under the background of climate warming.Soil samples were collect-ed 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 10.82-48.08mg·kg-1·h-1.The organic car-bon 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 cu-mulative 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 in-creasing 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 in-creasing temperature,leading to increased forest carbon emissions.
万方数据
维普
