As an important part of soil organic carbon pool, both forest soil organic carbon and its factors aresignificant for coping with climate change, were chosen in this study In this study, each 12 sampling points of two typical forest types (evergreen broad-leaved forest and Cunninghamia lanceolata plantation) in Jinggangshan National Natural Reserve were selected to compare vertical distribution characteristics of soil organic carbon density of these two kinds of forests, as well as to analyze their correlations with the annual average temperature and annual average rainfall. Results showed that the average density of soil organic carbon at 25.65±3.27 kg·m-2 in 0～100 cm level of the evergreen broad-leaved forest was higher than that of the Cunninghamia lanceolata plantation forest at 20.37±3.37 kg·m-2. The average density of soil organic carbon of both the evergreen broad-leaved forest and the Cunninghamia lanceolata plantation forest was significantly decreased with the increase of the soil depth. Statistics analysis clearlyshowed that the average density of soil organic carbon of both the evergreen broad-leaved forest and the Cunninghamia lanceolata plantation was significant with the change of the annual average temperature. The average density of soil organic carbon of the evergreen broad-leaved forest appeared a significant increase trend (P＜0.05) with the increase of the annual average temperature. Although the average density of soil organic carbon of the Cunninghamia lanceolata plantations firstly decreased, then increased, and finally decreased with the increase of the annual average temperature, their correlation was significant (P<0.05). At the same time, the change of the average density of soil organic carbon of evergreen broad-leaved forest and Cunninghamia lanceolata plantations was also significant with the change in annual average rainfall. The average density of soil organic carbon of the evergreen broad-leaved forest in 0 - 100 cm level appeared a significant decrease trend (P＜0.05) with the increase of the annual average rainfall. However, that of the Cunninghamia lanceolata plantations appeared a very significant decrease trend (p<0.005) with the increase of the annual aeverage rainfall, e.g., firstly increased, then decreased, and finally increased.. In addition, there was significantly negative correlation (P<0.0001) between the content of forest soil organic carbon and soil bulk density.%森林土壤有机碳是土壤有机碳库的重要组成部分,研究森林土壤有机碳及其影响因素对于应对气候变化具有非常重要意义.以井冈山自然保护区两种典型森林类型(常绿阔叶林和人工杉木林)为研究对象,各选取12个样地,对比分析了两种森林土壤有机碳密度的垂直分布特征以及与年均温、年降雨量之间的相关性.结果表明:①常绿阔叶林0～100 cm层平均土壤有机碳密度为(25.65±3.27) kg.m2,大于人工杉木林0～100 cm层平均土壤有机碳密度为(20.37±3.37) kg·m-2;②常绿阔叶林和人工杉木林土壤有机碳密度均随土壤深度的增加显著减少；③常绿阔叶林与人工杉木林土壤有机碳密度随年均温的变化趋势差异较明显,常绿阔叶林0～100 cm层土壤有机碳密度随年均温的上升呈显著增加趋势(P＜0.05),而人工杉木林随年均温的上升先减小后增加再减小,且变化趋势显著(P＜0.05)；④常绿阔叶林与人工杉木林土壤有机碳密度随年降雨量的变化趋势差异亦明显,常绿阔叶林0～100 cm层土壤有机碳密度随年降雨量的增加呈显著减小趋势(P＜0.05),而人工杉木林随年降雨量的增加先增加后减少再增加,且变化趋势极显著(P＜0.005)；⑤森林土壤有机碳质量分数与土壤容重呈极显著负相关(P＜0.000 1).
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