中国生态农业学报 2009年1月 第17卷 第1期 Chinese Journal of Eco-Agriculture, Jan. 2009, 17(1): 41 47

DOI: 10.3724/SP.J.1011.2009.00041

不同森林植被下土壤活性有机碳含量及其季节变化

张 剑1,2,3 汪思龙1,2** 王清奎1,2 刘燕新1,2,3

(1. 中国科学院沈阳应用生态研究所 沈阳 110016; 2. 湖南会同森林生态系统国家野外科学观测研究站 会同 418307;

3. 中国科学院研究生院 北京 100049)

*

摘 要 通过对湖南省会同县地区不同季节地带性常绿阔叶林、杉木纯林、火力楠纯林以及杉木火力楠混交林土壤各活性有机碳的含量测定, 分析了森林植被对土壤活性碳库及其季节变化的影响。结果表明, 常绿阔叶林转变为人工林后, 土壤活性有机碳含量明显降低; 与杉木纯林相比, 火力楠与杉木混交可提高土壤活性有机碳含量, 但只有土壤水溶性有机碳含量显著提高;各林地土壤活性有机碳具有明显的季节变化, 一年中土壤水溶性有机碳含量的大小始终为常绿阔叶林＞杉木火力楠混交林＞火力楠纯林＞杉木纯林, 土壤微生物量碳、热水浸提有机碳和碳水化合物则表现为常绿阔叶林＞火力楠纯林＞杉木火力楠混交林＞杉木纯林。与杉木纯林相比, 杉木火力楠混交林可提高林地质量, 但不同林地活性有机碳的季节变化规律表现不尽一致, 表明土壤活性有机碳的季节差异不仅与温度、降雨等气候因素有关, 还受到植被类型的影响。 关键词 杉木人工林 火力楠人工林 人工混交林 地带性常绿阔叶林 土壤活性有机碳 季节变化 中图分类号: S714.2 文献标识码: A 文章编号: 1671-3990(2009)01-0041-07

Content and seasonal change in soil labile organic carbon under

different forest covers

ZHANG Jian1,2,3, WANG Si-Long1,2, WANG Qing-Kui1,2, LIU Yan-Xin1,2,3

(1. Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; 2. Huitong National Research Station for

Forest Ecosystem, Huitong 418307, China; 3. Graduate University of Chinese Academy of Sciences, Beijing 100049, China)

Abstract Based on the concentrations of soil labile organic carbon (SLOC) pools under native evergreen broad-leaved forest (NBF), and three plantations of pure Cunninghamia lanceolata , pure Michelia macclurei and their mixed forest in different seasons, the effect of forest types on the content and seasonal changes of SLOC was analyzed for Huitong County of Hunan Province. The results show that SLOC content decreases after native evergreen broad-leaved forest are substituted by planted forest. Compared with C. lanceolata plantation, C. lanceolata and M. macclurei mixed forest (MCM) increases SLOC content. However, the difference is statistically insignificant except for water-soluble organic carbon (WSOC). Substantial seasonal fluctuations in SLOC under forests are observed. Throughout the year, WSOC decreases in the following order of NBF > MCM > pure M. macclurei plantation (PM) > pure C. lanceolata plantation (PCF). For soil microbial biomass carbon (MBC), hot-water extractable C (HWC) and hot-water ex-tractable carbohydrate-C (HWcC) is in the following order of NBF > PM > MCM > PCF. Compared with PCF, MCM increases soil quality. However, seasonal trends of SLOC under different forest covers are not completely consistent, suggesting that seasonal fluc-tuations in SLOC are influenced not only by climatic factors like temperature and precipitation, but also by vegetation type. Key words Cunninghamia lanceolata plantation, Michelia macclurei plantation, Planted mixed forest, Native evergreen broad-leaved forest, Soil labile organic carbon, Seasonal change (Received Feb. 1, 2008; accepted May 8, 2008)

土壤有机碳(Soil organic carbon, SOC)是土壤-

植物生态系统的重要组成部分, 对土壤物理、化学

* 国家自然基金项目(30470303)、中国科学院知识创新工程重要方向项目(KZCX2-YW-405)和中国科学院知识创新工程青年人才领域前 沿项目(07SBS116S3)资助

** 通讯作者: 汪思龙(1964~), 男, 博士, 研究员, 主要研究方向为森林生态学。E-mail: slwang@ 张剑(1981~), 男, 在读博士, 主要研究方向为森林生态与土壤生态恢复。E-mail: rczhjxmw@. -