Chin J Plant Ecol ›› 2009, Vol. 33 ›› Issue (2): 283-290.DOI: 10.3773/j.issn.1005-264x.2009.02.005

• Research Articles • Previous Articles     Next Articles

CARBON STOCK AND ITS ALLOCATION IN FIVE FOREST ECOSYSTEMS IN THE SUBALPINE CONIFEROUS FOREST ZONE OF WESTERN SICHUAN PROVINCE, SOUTHWEST CHINA

XIAN Jun-Ren1,2, ZHANG Yuan-Bin3, WANG Kai-Yun4, HU Ting-Xing2,*(), YANG Hua2   

  1. 1College of Resources and Environment, Sichuan Agricultural University, Ya’an, Sichuan 625014, China
    2College of Forestry and Horticulture, Sichuan Agricultural University, Ya’an, Sichuan 625014, China
    3Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
    4Shanghai Key Laboratory of Urbanization Processes and Ecological Restoration, East China Normal University, Shanghai 200062, China
  • Received:2008-03-03 Accepted:2008-04-18 Online:2009-03-03 Published:2009-03-31
  • Contact: HU Ting-Xing

Abstract:

Aims Forest ecosystems are important carbon pools of the global terrestrial ecosystem and play a key role in sequestrating and reserving greenhouse gases. Our objectives were to quantify the carbon stock of different forest ecosystems in the subalpine coniferous forest in western Sichuan Province (SCFS) and identify short-term carbon sequestration potential.

Methods We investigated the forests of Wanglang National Natural Reserve, located in Pingwu County, Sichuan Province. Five similar altitude and slope ecosystems dominated byBetula platyphylla(BF), Betula spp. and Abies faxoniana(MF),Abies faxoniana (FF), Picea purpurea(SF) and Sabina saltuaria(CF) were selected to quantify ecosystem carbon stock and its allocation. We sampled eight replicate plots in each ecosystem. All plants in each plot were surveyed and sorted into three groups: tree layer (DBH ≥5 cm), understory ( DBH <5 cm), and herb layer. We surveyed the carbon stock of the tree layer using standard tree sampling methods, in which biomass and carbon stock of three newly up-rooted trees were measured. Carbon stock of understory, herb, ground cover (including litter, lichens and coarse woody debris <2 cm diameter) and soil was measured by destructive sampling.

Important findings Soil organism carbon (SOC) decreased significantly with increased soil depth (p<0.01). Carbon stock contributions of ground cover were similar (3%-4% of the total). The tree layer had the largest plant carbon pool, and root carbon reached 13%-19% of plant carbon. The main carbon stock was in plants in SF and FF and in soil in MF, BF and CF. Ecosystem carbon stock was SF (729.92±43.49) > FF (618.86±53.97) > MF (353.88±21.76) > BF (247.79±17.15) > CF (244.52±18.70) 103 kgC·hm-2, and the difference was significant (p<0.05). Plant recent carbon stock potentials were 2.97, 3.80, 5.15, 3.33 and 4.84 103 kgC·hm-2·a-1, respectively. Therefore, the SCFS could play a key role in CO2sequestration. This provides insight into forest carbon sequestration capacity and, hence, into understanding global carbon balance.

Key words: carbon stock, carbon sequestration capacity, forest ecosystem, subalpine