西双版纳热带雨林主要树种的树干径流碳通量  

Effects of Tree Species on Carbon Fluxes from Stemflow in Xishuangbanna Tropical Rainforests

作　　者：祝正 乔青 宋清海[2,3] 沙丽清 张一平[2,3] 巩合德 周文君[2,3] ZHU Zheng;QIAO Qing;SONG Qinghai;SHA Liqing;ZHANG Yiping;GONG Hede;ZHOU Wenjun(Southwest Forestry University,Kunming Yunnan 650224,P.R.China;Key Laboratory of Tropical Forest Ecology,Chinese Academy of Sciences,Mengla Yunnan 666303,P.R.China;University of Chinese Academy of Sciences,Beijing 100049,P.R.China)

机构地区：[1]西南林业大学,云南昆明650224 [2]中国科学院西双版纳热带植物园热带森林生态学重点实验室,云南勐腊666303 [3]中国科学院大学,北京100049

出　　处：《西部林业科学》2024年第4期129-136,共8页Journal of West China Forestry Science

基　　金：国家自然科学基金项目(32361143516,42073080);云南省中青年学术和技术带头人后备人才项目(202205AC160045);云南省第四批博士后定向培养项目资助。

摘　　要：为探明热带雨林树干径流在森林碳收支中的地位和不同树种对树干径流碳通量的影响,本研究在中国西南部的西双版纳热带季节雨林选择6个优势树种(绒毛番龙眼、大叶白颜树、梭果玉蕊、细罗伞、蚁花、窄序崖豆),对树干径流量、总碳(total carbon,TC)通量及组分〔有机碳(total organic carbon,TOC)、无机碳(total inorganic carbon,TIC),溶解态有机碳(dissolved organic carbon,DOC)、溶解态无机碳(dissolved inorganic carbon,DIC)、颗粒态有机碳(particulate organic carbon,POC)和颗粒态无机碳(particulate inorganic carbon,PIC)〕开展为期1年的研究,结合该生态系统水文过程和森林生态系统碳通量的研究结果,探究树干径流在热带森林生态系统碳循环中的地位。结果显示:各碳组分的最高浓度均在雾凉季,除了POC的最低浓度在干热季外,其他碳组分平均最低浓度均在雨季。各碳组分除颗粒态无机碳和颗粒态有机碳外,其他组分的浓度均随径流量增加而减小。这6个优势树种由于树冠结构,有无附生植物以及树皮形态等方面的不同导致其树干径流量和碳动态的种间差异。有机碳是树干径流输出的主要形式,占总碳的82.43%;其中溶解态有机碳的输出比例最高,相当于全碳的71.30%,随后为溶解态无机碳(13.25%)、颗粒态有机碳(11.13%)和颗粒态无机碳(4.32%)。虽然树干径流量仅占总降雨量的0.62%,但树干径流的输出的年总碳(TC)通量为14.8 kg C·hm^(-2)·a^(-1),相当于生态系统的碳通量的1.18%。研究结果表明,该地区的树干径流在水量和碳输出方面对热带季节雨林的碳贡献相对较小。In the tropical seasonal rainforest of Xishuangbanna in southwestern China,we conducted a year-long study on the dynamics of stemflow volume and individual carbon fractions of six dominant tree species(Pometia tomentosa,Gironniera subaequalis,Barringtonia pendula,Ardisia tenera,Mezzettiopsis creaghii,Millettia leptobotrya)in the area,combining with long-time observations to investigate the role of stemflow in the carbon cycle of tropical forest ecosystems.The highest concentrations of each carbon component were found in the fog cool season,and the lowest average concentrations of all carbon components were found in the rainy season,except for particulate organic carbon(POC)in the dry hot season.Except for particulate inorganic and organic carbon,all carbon fractions showed significant negative correlation with stemflow volume.The six dominant tree species showed interspecific differences in stemflow and carbon dynamics due to differences in canopy structure,the presence or absence of epiphytes and bark morphology,etc.Organic carbon was the main form of stemflow output,accounting for 82.43%of the total carbon(TC),while dissolved organic carbon(DOC),dissolved inorganic carbon(DIC),particulate organic carbon(POC)and particulate inorganic carbon(PIC)accounted for 71.30%,13.25%,11.13%and 4.32%of the total carbon(TC),respectively.The stemflow amounted to only 0.62%of the total rainfall,and the annual total carbon(TC)flux from the output of stemflow was 14.8 C hm^(-2)·a^(-1),with a ratio(TC︰NEE)to the carbon flux of the ecosystem(NEE)of about 1.18%.The result of this study indicates that stemflow in this area contributes relatively little carbon to this tropical seasonal rainforest in terms of water volume and carbon output.

关 键 词：溶解态有机碳 溶解态无机碳 颗粒态有机碳 颗粒态无机碳 树干径流 

分 类 号：S715[农业科学—林学]