title: The role of stream water carbon dynamics and export in the carbon balance of a tropical seasonal rainforest, southwest China.
abstract: A two-year study (2009 ~ 2010) was carried out to investigate the dynamics of different carbon (C) forms, and the role of stream export in the C balance of a 23.4-ha headwater catchment in a tropical seasonal rainforest at Xishuangbanna (XSBN), southwest China. The seasonal volumetric weighted mean (VWM) concentrations of total inorganic C (TIC) and dissolved inorganic C (DIC) were higher, and particulate inorganic C (PIC) and organic C (POC) were lower, in the dry season than the rainy season, while the VWM concentrations of total organic C (TOC) and dissolved organic C (DOC) were similar between seasons. With increased monthly stream discharge and stream water temperature (SWT), only TIC and DIC concentrations decreased significantly. The most important C form in stream export was DIC, accounting for 51.8% of the total C (TC) export; DOC, POC, and PIC accounted for 21.8%, 14.9%, and 11.5% of the TC export, respectively. Dynamics of C flux were closely related to stream discharge, with the greatest export during the rainy season. C export in the headwater stream was 47.1 kg C ha(-1) yr(-1), about 2.85% of the annual net ecosystem exchange. This finding indicates that stream export represented a minor contribution to the C balance in this tropical seasonal rainforest.
authors: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, China.
authors: Wen-Jun
authors: WJ
authors: Zhou
authors: Yi-Ping
authors: YP
authors: Zhang
authors: Douglas A
authors: DA
authors: Schaefer
authors: Li-Qing
authors: LQ
authors: Sha
authors: Yun
authors: Y
authors: Deng
authors: Xiao-Bao
authors: XB
authors: Deng
authors: Kai-Jie
authors: KJ
authors: Dai
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002681:China; D017753:Ecosystem; D009584:Nitrogen / Q000737:chemistry; D011891:Rain; D045483:Rivers; D012621:Seasons; D013696:Temperature; D014197:Trees / Q000502:physiology*; D014329:Tropical Climate; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D002244:Carbon; D009584:Nitrogen