【作者】 姜发艳； 孙辉； 林波； 刘庆；

【Author】 JIANG Fayan~1,SUN Hui~1,LIN Bo~2,Liu Qing~2 (1.Department of Environmental Science and Engineering,Sichuan University,Chengdu,610065; 2.Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu,610041)

【机构】 中国科学院成都生物研究所； 四川大学建筑与环境学院；

【摘要】 人工林越来越成为全球至关重要的森林生态系统,但关于人工造林对土壤有机碳库及土壤有机碳矿化影响的研究,不同研究各不相同。本文采用室内培养法研究了川西亚高山不同恢复阶段（22、47、65年）云杉（Picea asperata Mast.）人工林及原始云杉林表层（0～30cm）土壤有机碳的矿化,并用两室模型对实验数据进行了回归。结果表明,不同恢复阶段云杉人工林各层土壤（0～10、10～20、20～30 cm）有机碳64天累积释放的CO₂-C在3.26和5.43 g kg^-1soil之间,大于原始林的2.21～2.42 g kg^-1soil。两室模型将土壤有机碳分为易矿化有机碳（Ca）和难矿化有机碳（Cs）。其中,云杉人工林各层土壤Ca大小为1.54～3.67 gkg^-1soil,大于原始林的0.77～1.04 g kg^-1soil。云杉人工林土壤Ca含量占总有机碳含量的比例（5%～15%）也大于原始林（1%～4%）,这表明原始林转化为云杉人工林后,土壤有机碳稳定性降低。土壤Ca和Cs的矿化速率常数(分别为0.0288～0.1283 g kg^-1d^-1&0.4648～3.3262×10^-3 g kg^-1d^-1)均随着人工林林龄增加而增加,但Ca矿化速率常数（Ka）小于原始林(0.1379～0.1500 g kg^-1d^-1),Cs矿化率常数（Ks）大于原始林(0.5354～0.8283×10^-3g kg^-1d^-1)。另外,本文对云杉人工林恢复过程中凋落物、微生物、土壤理化性质等可能影响土壤有机碳矿化的因素进行了分析。更多还原

【Abstract】 The significance and importance of planted forests has been recognized internationally. However,influence of reforestation on soil organic carbon sink and carbon dynamics has not been well understood.The dynamics of soil organic carbon of topsoil(0-30cm) in different age stand (22-,47-,65-year old) of planted spruce(Picea asperata Mast.) forests and primary spruce forest in subalpine areas in the western Sichuan Province were determined using laboratory incubation and data were regressed through double exponential model.Results show that the cumulative emission of CO2-C from different age classes of planted forest soil(0-10cm,10-20cm,20-30cm) are ranging from 3.26 to 5.43g kg-lsoil,larger than that in primary forest(2.21-2.42g kg-1soil) during the 64 days of soil incubation.Soil organic carbon can be divided into active carbon pool(Ca) and slow carbon pool(Cs) by regressed with a double exponential model in which topsoil Ca of planted forests(2-3g kg-1soil) are higher than that of primary forest(0.77-1.04g kg-1soil),and the proportions of topsoil Ca to TOC of planted forests(5%-15%) are also higher than that of primary forest(1%-4%).This indicates that the stability of soil organic carbon is weakened while primary forest was turned into planted forests.Mineralize rate constants of Ca and Cs(0.0288-0.1283g kg-1d-1and 0.4648-3.3262×10-3g kg-1d-1,respectively) of planted forest also increased with age. Mineralize rate constants of Cs of planted forests are higher than that of primary forest (0.5354-0.8283×10-3g kg-1d-1).However,mineralize rate constants of Ca seem to be lower than that of primary forest(0.1379-0.1500g kg-1d-1).In addition,we discussed factors like litter, microorganisms and soil quality that may influence soil carbon mineralization of spruce forest succession.更多还原