大兴安岭多年冻土区典型森林秋季冻融期土壤活性碳变化特征  

Characteristics of Soil Active Carbon Changes During Autumn Freeze-thaw Period in Typical Forests in the Permafrost Region of the Great Daxing′an Mountains

作　　者：张富新 满秀玲[1,2] ZHANG Fuxin;MAN Xiuling(College of Forestry,Northeast Forestry University,Harbin 150040,China;Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学林学院,哈尔滨150040 [2]东北林业大学森林生态系统可持续经营教育部重点实验室,哈尔滨150040

出　　处：《森林工程》2024年第6期11-19,共9页Forest Engineering

基　　金：国家重点研发项目(2021YFD2200405)。

摘　　要：探究大兴安岭多年冻土区3种林型秋季冻融期土壤活性碳变化特征及其主要影响因素,为多年冻土区森林土壤碳汇管理提供帮助。以兴安落叶松林(LY)、樟子松林(ZZ)和白桦林(BH)为研究对象,于2022年10月10日至11月18日对不同土层(0~5、5~10、10~20 cm)土壤进行取样,测定其土壤活性碳组分(可溶性有机碳、微生物量碳、易氧化有机碳)质量分数,探究其动态特征及其影响因子。结果显示,10月10日至11月18日兴安落叶松林、白桦林和樟子松林土壤温度均随气温下降而降低,变化范围分别为-0.49~3.71、-2.10~2.39、-1.04~3.48℃。3种林型不同土层土壤可溶性有机碳(DOC)质量分数随着温度的降低呈先升高后降低的变化趋势,微生物量碳(MBC)质量分数先减少后增加,易氧化有机碳(ROC)质量分数则波动式变化,变化范围分别为78.75~214.32、101.06~988.40、1.52~13.94 g/kg,其中,白桦林土壤DOC和ROC质量分数显著高于兴安落叶松林和樟子松林,而土壤MBC质量分数在兴安落叶松林中最高。3种活性碳在不同林型内均呈“表聚效应”,且冻融期内土壤DOC质量分数增加,土壤MBC质量分数减少,但土壤ROC质量分数变幅不大。兴安落叶松林土壤活性碳组分质量分数变化主要受土壤水分和微生物量氮影响,铵态氮是影响白桦林3种土壤活性碳的主导因子,樟子松林3种土壤活性碳的主要影响因子是土壤pH。研究表明,冻融作用对大兴安岭多年冻土区典型森林土壤活性碳影响较大,增加了土壤DOC质量分数,降低了土壤MBC质量分数,对ROC质量分数的影响相对较小。To explore the changes and main influencing factors of soil active carbon during the autumn freeze-thaw period of three forest types in the permafrost region of the Great Daxing′an Mountains,and to provide assistance for forest soil carbon sink manage⁃ment in the permafrost region.Taking the Larix gmelinii forest(LY),Pinus sylvestris var.mongolica forest(ZZ)and Betula platy⁃phylla forest(BH)as the research objects,soil samples were taken from different soil layers(0-5,5-10,and 10-20 cm)to deter⁃mine the content of soil active carbon components(dissolved organic carbon,microbial biomass carbon,and readily oxidizable or⁃ganic carbon)from October 10th to November 18th,2022,and to explore their dynamic characteristics and influencing factors.Re⁃sults showed that,from October 10th to November 18th,the soil temperature in the Larix gmelinii forest,Betula platyphylla forest and Pinus sylvestris var.mongolica forest all decreased with decreasing temperature,with ranges of-0.49 to 3.71,-2.10 to 2.39,and-1.04 to 3.48℃,respectively.The content of dissolved organic carbon(DOC)in different soil layers of three forest types showed a trend of first increasing and then decreasing with the decrease of temperature,the content of microbial biomass carbon(MBC)first de⁃creased and then increased,while the content of readily oxidizable organic carbon(ROC)fluctuated,ranging from 78.75 to 214.32,101.06 to 988.40,and 1.52 to 13.94 g/kg,respectively.Among them,the soil DOC and ROC contents in the Betula platyphylla for⁃est were significantly higher than those in the Larix gmelinii forest and Pinus sylvestris var.mongolica forest,while the soil MBC con⁃tent was the highest in the Larix gmelinii forest.The three types of active carbon showed a‘surface aggregation effect’in different for⁃est types,and the soil DOC content increased and the soil MBC content decreased during the freeze-thaw period,but the soil ROC content did not change significantly.The changes in soil active carbon content in Larix gmelinii forest w

关 键 词：多年冻土区 秋季冻融期 可溶性有机碳 微生物量碳 易氧化有机碳 

分 类 号：S714.2[农业科学—林学]