摘要
采用密闭培养法,研究了小叶章(Deyeuxia angustifolia)湿地土壤有机碳的矿化动态,探讨了温度和水分条件对有机碳矿化的影响。结果表明:湿地土壤有机碳在培养初期(0～2d)矿化速率较高,之后矿化速率逐渐降低;33d培养期间,表层(0～10cm)土壤的总矿化量为1.59～2.62mgC.g-1,为下层(10～100cm)的4～22倍;温度升高10℃使总矿化量分别增加60%～210%(75%WHC)和30%～200%(淹水);一级动力学方程能较好地描述湿地土壤有机碳矿化动态,其C0值随土壤深度呈指数递减变化,且C0和C0/SOC值均随温度的升高而升高;不同深度土壤Q10值分别变化为1.7～3.1(75%WHC)和1.2～3.0(淹水),且与土壤深度之间存在明显的二次抛物线相关;土壤深度、培养温度对湿地土壤有机碳矿化具有显著影响,而水分处理对有机碳矿化的影响不显著。
By the method of airtight incubation, this paper studied the dynamic changes of soil organic carbon （SOC） mineralization in Deyeuxia angustifolia wetland, and approached the effects of temperature and soil moisture on the mineralization rate of SOC. The results showed that the SOC mineralization rate was higher in the first 2 days of incubation, but decreased gradually then. Within the period of incubation （33 days）, the total amount of mineralized organic carbon in topsoil （0-10 cm） ranged from 1.59 mg C · g^-1 to 2.62 mg C · g^-1 , being 4-22 folds of that in subsoil （ 10-100 cm）. In two water treatments, i. e. , 75 % of water-holding capacity （WHC） and flooding, this value increased by 60%-210% and 30%-200% , respectively, when the temperature increased 10 degree. The dynamics of SOC mineralization preferably followed the firstorder kinetics, and the C0 value decreased exponentially with soil depth. Both the C0 value and the C0/SOC ratio were also increased with increasing temperature. The Q10 values ranged in 1.7 -3. 1 （treatment 75% of WHC） and 1.2-3.0 （treatment flooding）, and significantly polynomially related to soil depth, indicating that temperature and soil depth affected the SOC mineralization in wetland significantly, while soil moisture did not.
出处
《生态学杂志》
CAS
CSCD
北大核心
2008年第1期38-42,共5页
Chinese Journal of Ecology
基金
国家自然科学基金项目(20477029和90211003)
沈阳大学博士启动基金资助项目
关键词
有机碳矿化
温度
土壤水分
湿地土壤
organic carbon mineralization
temperature
soil moisture
wetland soil.
