植物生态学报 ›› 2011, Vol. 35 ›› Issue (11): 1182-1191.DOI: 10.3724/SP.J.1258.2011.01182

• 研究论文 • 上一篇    下一篇

干旱区琵琶柴群落细根周转对土壤有机碳循环的贡献

裴智琴1,2, 周勇1,2, 郑元润1, 肖春旺1,*()   

  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
  • 收稿日期:2011-04-18 接受日期:2011-07-18 出版日期:2011-04-18 发布日期:2011-11-07
  • 通讯作者: 肖春旺
  • 作者简介:*(E-mail:cwxiao@ibcas.ac.cn)

Contribution of fine root turnover to the soil organic carbon cycling in a Reaumuria soon- goricacommunity in an arid ecosystem of Xinjiang Uygur Autonomous Region, China

PEI Zhi-Qin1,2, ZHOU Yong1,2, ZHENG Yuan-Run1, XIAO Chun-Wang1,*()   

  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
  • Received:2011-04-18 Accepted:2011-07-18 Online:2011-04-18 Published:2011-11-07
  • Contact: XIAO Chun-Wang

摘要:

尽管干旱区生态系统的脆弱性受到了广泛的关注, 但目前关于干旱区植物细根有机碳与土壤碳循环关系的研究还比较少见。在2010年整个生长季节内, 采用土钻法和内生长法, 对新疆干旱区的琵琶柴(Reaumuria soongorica)群落土壤特性、细根的生物量月动态、生产量和周转进行了研究。结果表明: 琵琶柴群落表层土壤含水量最低, 土壤含水量表现出从浅层到深层逐渐增加的趋势; 而表层土壤的有机碳含量最高, 随着土壤深度的加深, 有机碳含量逐渐降低。细根生物量的月平均值为54.51 g·m-2, 群落细根生产量在82.76-136.21 g·m-2·a-1之间, 琵琶柴群落的细根周转率为2.08 times·a-1, 通过细根死亡进入土壤中的有机碳为17 g·m-2·a-1。这些结果表明: 由于灌丛细根高的周转速率, 细根是干旱区土壤有机碳输入的重要部分。

关键词: 干旱区生态系统, 细根, 琵琶柴群落, 土壤有机碳, 土壤水分

Abstract:

Aims Our objective was to investigate the soil organic carbon stock, fine root turnover and its contribution to soil carbon cycling of Reaumuria soongorica community in an arid ecosystem in Xinjiang Uygur Autonomous Region, China.
Methods We selected a R. soongorica community, a typical local community, in natural areas around the Ecological Station of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences. We investigated the distribution and dynamics of soil organic carbon, monthly fine root dynamics, production and turnover rate throughout the 2010 growing season by means of sequential coring and ingrowth core. We calculated the soil organic carbon pool, fine roots carbon stocks and contribution of fine roots.
Important findings Soil water content increased with depth, but soil organic carbon decreased. The mean fine root mass in the community was 54.51 g·m-2, and annual fine root production was estimated to be 82.76-136.21 g·m-2·a-1. Fine root turnover rate in the community was 2.08 times·a-1, and annual inputs from fine root mortality to belowground soil organic carbon was 17 g·m-2·a-1. These results demonstrate that due to the high turnover rate of shrub fine root in the arid region, shrub fine root carbon is a crucial portion of soil organic carbon inputs.

Key words: arid ecosystem, fine root, Reaumuria soongorica community, soil organic carbon, soil water