土壤温、湿度对长白山阔叶红松林不同土壤层呼吸速率的影响

Effects of Soil Temperature and Moisture on Soil Respiration in Different Soil Layers in Broad-leaved Korean Pine Forests in Changbai Mountain

在实验室条件下,研究土壤温度与湿度对长白山阔叶红松林不同深度土壤呼吸速率的影响。结果显示:枯枝落叶层、半分解层和壤土层的呼吸速率均随温度的升高呈指数增加趋势,而白浆土层与黄土层的呼吸速率先随温度的升高而增大;当温度超过15℃时,呼吸速率随温度升高而减小。枯枝落叶层、半分解层的呼吸速率随含水量的增加而呈线性增大;壤土层的呼吸速率随土壤含水量的增加呈先增大后减小的趋势,当土壤含水量约为36%时,土壤呼吸速率达到最大;白浆土层与黄土层的呼吸速率与土壤含水量没有明显的相关关系。浅层土壤对土壤温度和湿度的响应要比深层土壤敏感;各层土壤的呼吸速率贡献率会随着温度变化而发生改变,深层土壤呼吸速率在低温时期的贡献率要大于高温时期。

An experiment was conducted to study the effects of soil temperature and water content on soil respiration in different soil layers in broad-leaved Korean pine forests in Changbai Mountain under laboratory conditions.Results showed that the soil respiration in the litter layer,semi-decomposed litter layer and loam layer increased exponentially with increasing soil temperature,and the soil respiration in the albic soil layer and loess layer firstly increased with increasing soil temperature,and then decreased when soil temperature exceeded 15 degrees C.The soil respiration in the litter layer and semi-decomposed litter layer increased linearly with soil water content.The soil respiration rate for the loam layer firstly increased and then decreased with increasing soil water content,and it reached its maximum value when soil water content was approximate to 36%.However,there was no significant relationship between respiration rate and soil water content in the albic soil layer and loess layer.The response of soil respiration in the shallow layer to soil temperature and water content was more sensitive than that in the deep layer.The contribution rate of soil respiration rate in each soil layer changed with temperature,and the contribution of respiration rate in the deep layer at low temperatures was greater than that at high temperatures.