Spatiotemporal variations of CO_(2) fluxes in a Cynodon-dominated riparian zone of the Three Gorges Reservoir(TGR),China  

作　　者：Wenli Zhang Jiquan Chen Ju Liu Fangqing Chen Quanfa Zhang Zutao Ouyang Changliang Shao Yi Fan Wennian Xu 

机构地区：[1]College of Biological and Pharmaceutical Sciences,China Three Gorges University,Yichang,Hubei 443002,China [2]Hubei International Scientific and Technological Cooperation Center of Ecological Conservation and Management in Three Gorges Area,China Three Gorges University,Yichang,443002,China [3]Center for Global Change and Earth Observations/Geography,Environment and Spatial Sciences,Michigan State University,East Lansing,MI 48823,USA [4]Key Laboratory of Aquatic Botany and Watershed Ecology,Wuhan Botanical Garden,the Chinese Academy of Sciences,Wuhan 430074,China

出　　处：《Journal of Plant Ecology》2018年第6期877-886,共10页植物生态学报（英文版）

基　　金：This research was a part of the project funded by the National Natural Science Foundation of China(NSFC)(NO.30900196 and NO.51278281)to Three Georges University;It was also funded by Natural Science Foundation of Hubei Province(2015CFC834);Provincial Department of Education Scientific research projects(Q20151209);the Key Laboratory of Aquatic Botany and Watershed Ecology at the Chinese Academy of Sciences,and Engineering Research Center of Eco-environment in Three Gorges Reservoir Region,Ministry of Education(KF2016-03).

摘　　要：Aims Riparian ecosystems play an important role in overall ecosystem function,including the global carbon cycle of terrestrial ecosystems,at both landscape and global scales.Yet few studies have reported in situ measurements of CO_(2) in riparian areas where flooding is a unique disturbance to carbon cycling.Methods At multiple locations across riparian zones(RZ)with different water submergences in Xiangxi Bay(XXB),we studied seasonal variations of CO_(2) exchange between this Cynodon-dominated community and the atmosphere for 2 years by using static chambers.Important Findings We found that the seasonal changes in CO_(2) fluxes were apparent and dependent on the biophysical environment.In the beginning of spring,low gross primary productivity(GPP)in lightly flooded zones(LFZ)resulted in a positive net ecosystem exchange(NEE),indicating a net CO_(2) source.With the increase in temperature,more species and vegetation abundance appeared,and the increased GPP turned the LFZ from a net CO_(2) source into a sink.This transi-tion seemed predominantly controlled by the physiological growth of vegetation.The mean NEEs,REs and the light-use efficiency(α)of the vegetation at HFZ and MFZ were significantly higher than those at LFZ and UFZ.Yet the coefficients of variation(CV)of NEE and RE at MFZ and HFZ were lower than those at LFZ and UFZ.Submergence promoted the emission and uptake of CO_(2) to the atmosphere.Elongated submergence reduced the number of spe-cies and lowered the spatial variability of the RZ,further lowering the variation of the CO_(2) exchange.

关 键 词：CO_(2)exchange RIPARIAN SUBMERGENCE spatial variability Q_(10) TGD 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]