川西亚高山云杉人工林恢复过程中土壤有机碳矿化研究

Soil Organic Carbon Mineralization of Subalpine Spruce Plantation in Western Sichuan Province

研究了川西亚高山云杉(Picea asperata Mast.)人工林不同阶段(22、47、65年)及原始林表层(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、20～30cm)有机碳64天累积释放的CO2-C显著大于原始林。两室模型模拟土壤有机碳矿化过程得出土壤活性有机碳(AC)含量及其占总有机碳含量的比例均大于原始林,表明原始林转化为云杉人工林后,土壤有机碳稳定性降低。此外,本文分析了凋落物、微生物、土壤理化性质等因素对云杉人工林土壤有机碳矿化的可能影响。

Organic carbon mineralization of topsoil（0-30cm） of spruce（Picea asperata Mast.） plantations at different succession stages（22-,47-and 65-year old） and primary spruce forest in subalpine areas in western Sichuan Province were determined,and data were analyzed and regressed by two-compartment model.The results showed that all of the cumulative emissions of CO2-C from different soil layers（0-10 cm,10-20 cm and 20-30 cm） in all plantations were higher than those in soils of primary forest in the 64-day incubation.Soil active carbon（AC） pool of plantation was higher than that of primary forest,and the ratio of soil AC to TOC in plantations was also higher than that of primary forest.This result indicated that the stability of soil organic carbon decreased with the transformation of primary forests to plantations.Additionally,possible impacts of quality and quantity of forest litter,soil microorganisms,and soil physical and chemical parameters on soil organic carbon mineralization in subalpine spruce were also discussed in this paper.