植物生态学报 ›› 2011, Vol. 35 ›› Issue (7): 722-730.DOI: 10.3724/SP.J.1258.2011.00722

• 研究论文 • 上一篇    下一篇

神农架海拔梯度上4种典型森林的土壤呼吸组分及其对温度的敏感性

罗璐1,2,3, 申国珍1,3, 谢宗强1,3,*(), 周利光4   

  1. 1中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
    2中国科学院研究生院, 北京 100049
    3湖北神农架森林生态系统国家野外科学观测研究站, 湖北兴山 443700
    4内蒙古大学生命科学学院, 呼和浩特 010021
  • 发布日期:2011-08-18
  • 通讯作者: 谢宗强
  • 作者简介:* E-mail: Xie@ibcas.ac.cn

Components of soil respiration and its temperature sensitivity in four types of forests along an elevational gradient in Shennongjia, China

LUO Lu1,2,3, SHEN Guo-Zhen1,3, XIE Zong-Qiang1,3,*(), ZHOU Li-Guang4   

  1. 1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2Graduate University of Chinese Academy of Sciences, Beijing 100049, China
    3National Field Station for Forest Ecosystem in Shennongjia, Hubei, Xingshan, Hubei 443700, China
    4College of Life Sciences, Inner Mongolia University, Hohhot 010021, China
  • Published:2011-08-18
  • Contact: XIE Zong-Qiang

摘要:

量化森林土壤呼吸及其组分对温度的响应对准确评估未来气候变化背景下陆地生态系统的碳平衡极其重要。该文通过对神农架海拔梯度上常绿阔叶林、常绿落叶阔叶混交林、落叶阔叶林以及亚高山针叶林4种典型森林土壤呼吸的研究发现: 4种森林类型的年平均土壤呼吸速率和年平均异养呼吸速率分别为1.63、1.79、1.74、1.35 μmol CO2·m-2·s-1和1.13、1.12、1.12、0.80 μmol CO2·m-2·s-1。该地区的土壤呼吸及其组分呈现出明显的季节动态, 夏季最高, 冬季最低。4种森林类型中, 阔叶林的土壤呼吸显著高于针叶林, 但阔叶林之间的土壤呼吸差异不显著。土壤温度是影响土壤呼吸及其组分的主要因素, 二者呈显著的指数关系; 土壤含水量与土壤呼吸之间没有显著的相关关系。4种典型森林土壤呼吸的Q10值分别为2.38、2.68、2.99和4.24, 随海拔的升高土壤呼吸对温度的敏感性增强, Q10值随海拔的升高而增加。

关键词: 自养呼吸, 异养呼吸, Q10值, 土壤含水量, 土壤温度

Abstract:

Aims Quantifying forest soil respiration (Rs), its components of heterotrophic respiration (RH) and autotrophic respiration (RA), and their responses to temperature are vital to accurately evaluate response of the terrestrial carbon balance to future climate change. Our specific objectives were to (1) compare patterns of soil respiration of four types of forests, (2) evaluate relationships among soil respiration and temperature and water content and (3) find the regulation of Q10 value in relation to elevation.
Methods Four types of forests along an elevational gradient at Shennongjia were investigated. The trenching plot approach was used to partition soil respiration into autotrophic respiration and heterotrophic respiration. Rates of soil respiration were measured twice a month from July 2009 to June 2010. Soil temperature and soil water content were measured at the same time.
Important findings Annual soil respiration of the four types of forests was 1.63, 1.79, 1.74 and 1.35 μmol CO2·m-2·s-1, and annual heterotrophic respiration was 1.13, 1.12, 1.12, 0.80 μmol CO2·m-2·s-1. Soil respiration and its components displayed obvious seasonal dynamics, with maximum values in summer and minimum values in winter. The soil respiration flux of broad-leaved forest was significantly higher than that of coniferous forests, but there was no obvious differentiation between broad-leaved forests. Soil temperature was the main factor that affected soil respiration and its components, and there were significant exponential relationships between them. There was no significant relationship between soil water content and soil respiration flux, except in broad-leaved forest with a mild inhibition phenomenon. Q10 values of four types of forests were 2.38, 2.68, 2.99 and 4.24. Soil respiration was more sensitive to temperature along the elevation gradient, while Q10 value increased with elevation increase.

Key words: autotrophic respiration (RA), heterotrophic respiration (RH), Q10 value, soil water content, soil temperature