The organic layer (OL) on the floor of three subalpine forests, dominated by spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF) and birch (Betula platyphylla Sukaczev) (BF) trees, respectively, was divided into a fresh litter layer (LL), semi-decomposed litter layer (FL) and decomposed litter layer (HL), and organic carbon (OC) stock, microbial biomass carbon (Cmic) and nitrogen (Nmic) and the activities of invertase, catalase, dehydrogenase and polyphenol oxidase were measured simultaneously in the OL and mineral soil (MS) in order to obtain an understanding of the status of the OC pool and biochemical properties at the interface between the soil and vegetation. The OC stock was 29.38 Mg hm-2±1.28 Mg hm-2 in the OL in SF, 22.7 Mg hm-2±1.12 Mg hm-2 in FF and 8.63 Mg hm-2±0.95 Mg hm-2 in BF, accounting for 62.2, 53.5 and 36.6% of the total OC stock, respectively. 92.8, 99.6 and 78.7% of the total OC in the SF, FF and BF forests were stored in the OL and humus layer, respectively. Regardless of the stand type, HL had the highest bacterial number, Cmic, Nmic and catalase activity, and FL had the highest numbers of fungal and actinomycetes and the highest activities of invertase, dehydrogenase and polyphenol oxidase. The vertical distribution patterns for microbial number, microbial biomass and enzyme activity imply that the OL is one of the most active interfaces between the soil and the vegetation.%为了解土壤和植被界面的有机碳库和生化特性,分别将以云杉(Picea purpurea Masters) (SF)、冷杉(Abies faxoniana Rehder & E.H.Wilson) (FF)和白桦(Betula platyphylla Sukaczev) (BF)为优势树种的3个亚高山森林地表有机层(OL)分成新鲜凋落物层(LL)、半分解层(FL)和分解层(HL),并同步测定了有机层和矿质土壤层(MS)的有机碳(OC)储量、微生物生物量碳(Cmic)、微生物生物量氮(Nmic)及转化酶、过氧化氢酶、脱氢酶和多酚氧化酶活性.云杉林、冷杉林和白桦林土壤有机层的有机碳储量分别为29.38 Mg hm-2±1.28 Mg hm-2、22.7 Mg hm-2±1.12 Mg hm-2和8.63 Mg hm-2±0.95 Mg hm-2,分别为总有机碳储量的62.2%、53.5%和36.6%.云杉林、冷杉林和白桦林土壤有机层和腐殖质层分别储存了92.8%、99.6%和78.7%的有机碳.所有林型中,HL具有最高的细菌数量、Cmic和 Nmic及过氧化氢酶活性,FL具有最高的真菌、放线菌数量及转化酶、脱氢酶和多酚氧化酶活性.微生物数量、微生物生物量和酶活性的垂直分布格局意味着OL是土壤和植被之间最活跃的生态界面之一.
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