中文摘要：

采用对比分析方法，研究了红松阔叶混交林不同演替阶段（形成阶段、发展阶段、稳定阶段和顶级群落）、不同土层各形态土壤活性有机碳变化。结果表明：土壤溶解性有机碳（DOC）、微生物量碳（MBC）和易氧化态碳（EOC）含量均随着演替的进展呈上升趋势。土壤溶解性有机碳、微生物量碳、易氧化态碳含量均随着土层深度加深而递减。其中，不同演替阶段易氧化态碳占总有机碳比率随剖面加深有规律地下降，而土壤水溶性有机碳占总有机碳比率随剖面从上到下均表明出上升趋势。A层土壤水溶性碳和微生物量碳占总有机碳比率最大，C层易氧化态碳占总有机碳比率明显高于A层和B层。土壤有机碳总量与各活性有机碳之间以及各类活性有机碳碳与土壤养分之间的相关性均达到显著水平或极显著水平。

英文摘要：

Soils in different depths under different stages （formation stage, development stage, stabilization phase and top Community） of Korean pine and broadleaf forest were selected and soil samples were analyzed for different fractions of carbon and soil nutrients using the method of contrast and statistical analysis. The results showed that contents of soil dissolved organic carbon（ DOC ）, microbial biomass carbon （MBC）and easily oxidized carbon（ EOC ）all increased with the increase of age, and mainly reached balance when they reached maturity. And the contents of all these fractions of carbon decreased with the increase of depth. DOC% and MBC% of soil in A layer were much more than B layer and C layer, and EOC% of soil in C layer was much more than A layer and B layer. The proportion that EOC took the total organic carbon decreased gradually with increase of soil depth, while DOC increased obviously with increase of soil depth. Correlations between soil total organic carbon and different active organic carbons and correlations between active soil organic carbons and soil nutrients all reached significant level.