The fluxes and controlling factors of N_2O and CH_4 emissions from freshwater marsh in Northeast China  

作　　者：YU JunBao1,2, LIU JingShuang2, SUN ZhiGao1, SUN WeiDong3, WANG JinDa2, WANG GuoPing2 & CHEN XiaoBing1 1 Key Lab of Coastal Envionment Processed, Yantai Institute of Coastal Zone Research for Sustainable Development, Chinese Academy of Sciences, Yantai 264003, China 2 Key Lab of Wetland Ecology and Environment, Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012, China 3 Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 

出　　处：《Science China Earth Sciences》2010年第5期700-709,共10页中国科学（地球科学英文版）

基　　金：supported by Knowledge Innovation Project of the Chinese Academy of Sciences (Grant Nos. KZCX2-YW-223, KZCX2-YW-309);the CAS/SAFEA International Partnership Program for Creative Research Teams, National Natural Science Foundation of China(Grant No. 40873062);the 100 Talents Program of the Chinese Academy of Sciences and the Science and Technology Development Program Project of Shandong Province (Grant Nos. 2008GG20005006 and 2008GG3NS07005)

摘　　要：Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast China, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast China, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.

关 键 词：FREEZE-THAW region FRESHWATER MARSH methane nitrous oxide controlling factors 

分 类 号：P402[天文地球—大气物理学与大气环境]