植物生态学报 ›› 2013, Vol. 37 ›› Issue (9): 803-810.DOI: 10.3724/SP.J.1258.2013.00084

• 研究论文 • 上一篇    下一篇

浙江天童常绿阔叶林演替过程中土壤碳库与植被碳归还的关系

孙宝伟1,2, 杨晓东1,2, 张志浩, 马文济1,2, 黄海侠1,2, 阎恩荣1,2,*()   

  1. 1华东师范大学环境科学系, 上海 200241
    2浙江天童森林生态系统国家野外科学观测研究站, 浙江宁波 315114
  • 收稿日期:2013-04-15 接受日期:2013-07-19 出版日期:2013-04-15 发布日期:2013-09-02
  • 通讯作者: 阎恩荣
  • 作者简介:*E-mail: eryan@des.ecnu.edu.cn
  • 基金资助:
    国家自然科学基金海外及港澳学者合作研究基金(31228004)

Relationships between soil carbon pool and vegetation carbon return through succession of evergreen broad-leaved forests in Tiantong region, Zhejiang Province, Eastern China

SUN Bao-Wei1,2, YANG Xiao-Dong1,2, ZHANG Zhi-Hao, MA Wen-Ji1,2, Ali ARSHAD1,2, HUANG Hai-Xia1,2, YAN En-Rong1,2,*()   

  1. 1Department of Environment Science, East China Normal University, Shanghai 200241, China
    2Tiantong National Forest Ecosystem Observation and Research Station, Ningbo, Zhejiang 315114, China
  • Received:2013-04-15 Accepted:2013-07-19 Online:2013-04-15 Published:2013-09-02
  • Contact: YAN En-Rong

摘要:

土壤碳固持量随森林演替显著提高, 对减缓全球变暖具有重要意义; 但是, 演替过程中土壤有机碳库与植被碳归还的关系尚无定论。该研究以浙江天童常绿阔叶林次生演替系列为对象, 通过测定前中后3个演替阶段土壤总有机碳(TOC)、可矿化碳(MC)、可溶性有机碳(DOC)和微生物量碳(MBC) 3种活性有机碳的含量与储量, 植被凋落物年凋落量、地表枯落物现存量和细根年归还量及其碳储量, 利用相关分析和多元逐步回归拟合, 分析土壤碳库与植被碳输入的关系。结果表明: (1)土壤TOC、MC、DOC和MBC含量随演替进行均显著增加(p < 0.05); (2)随演替进行, 土壤TOC储量显著增加( p < 0.05), 而MC、DOC和MBC储量并没有出现一致的变化趋势, 其排序为: 中期>后期>前期; (3)凋落物年凋落量及其碳储量随演替显著增加( p < 0.05), 细根年归还量及其碳储量随演替先增后降( p < 0.05), 而地表枯落物现存量与碳储量显著降低; (4) 3种活性有机碳中, MC储量对土壤总有机碳储量解释的贡献率为34.01% ( R2 = 0.388, p < 0.05); (5) TOC和活性碳库(MC、DOC、MBC)受到不同碳归还方式的影响, 但细根的影响最大(分别为28.2%、50.0%、73.4%和68.8%)。总之, 随天童常绿阔叶林演替发生, 土壤总有机碳和3种活性有机碳储量显著增加, 细根生物量和可矿化碳库储量增加是引起土壤碳固持量增加的主要原因。

关键词: 活性有机碳, 细根, 地表枯落物, 凋落物, 次生演替, 总有机碳

Abstract:

Aims Increasing sequestration of soil organic carbon with forest succession plays a significant role in reducing global warming. However, the relationship between structure of soil carbon pools and vegetation carbon inputs is still uncertain. Our objective was to examine how structure of the soil carbon pool changes with vegetation carbon return through litterfall, forest floor and fine roots during secondary succession in evergreen broad-leaved forests.
Methods The study site is located in Tiantong National Forest Park (29°52′ N, 121°39′ E), Zhejiang Province, in Eastern China. Three successional stages (i.e., early, middle and late stages) were selected to examine contents and stocks for carbon pools for each of total soil organic carbon (TOC), mineralization carbon (MC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC). The amounts of vegetation carbon return through each of the litterfall, forest floor and fine roots were determined. Then relationships between carbon pool stocks and amount of vegetation carbon return were determined by using both Pearson correlation and stepwise regression approaches.
Important findings Along the forest successional series, contents of TOC, MC, DOC and MBC increased significantly (p < 0.05). Stocks of TOC also increased through forest succession ( p < 0.05), but the other three active organic carbon stocks were highest in middle-, intermediate in late- and lowest in early-successional stages. The amounts of annual biomass and carbon stocks increased for litterfall, but decreased for forest floor, and fine roots annual returned mass and carbon stocks were highest in middle-, intermediate in late- and lowest in early-successional stages ( p < 0.05). Among three active organic carbon pools, MC explained 34.01% variation in TOC ( R2= 0.388, p < 0.05). With respect to vegetation carbon return, returned biomass of fine roots explained 28.2%, 50.0%, 73.4% and 68.8% of total variation for TOC, MC, DOC and MBC, respectively. In conclusion, stocks of TOC and three active organic carbon pools elevate gradually with secondary forest succession in the study area. During this process, the accumulation of fine roots and the enhancement of mineralization carbon pool are mainly responsible for soil carbon sequestration.

Key words: active organic carbon, fine root, forest floor, litterfall, secondary succession, total organic carbon