Open AccessInter-Annual Variability of Area-Scaled Gaseous Carbon Emissions from Wetland Soils in the Liaohe Delta, China
Author(s) -
Siyuan Ye,
Ken W. Krauss,
Hans Brix,
Wei Mu,
Lena Olsson,
Xueyang Yu,
Xueying Ma,
Jin Wang,
Hongming Yuan,
Guangming Zhao,
Xigui Ding,
Rebecca F. Moss
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0160612
Subject(s) - wetland , phragmites , environmental science , greenhouse gas , biogeochemical cycle , delta , soil water , carbon sequestration , soil carbon , methane , carbon dioxide , salinity , carbon cycle , hydrology (agriculture) , environmental chemistry , ecology , ecosystem , soil science , chemistry , geology , geotechnical engineering , engineering , biology , aerospace engineering
Global management of wetlands to suppress greenhouse gas (GHG) emissions, facilitate carbon (C) sequestration, and reduce atmospheric CO 2 concentrations while simultaneously promoting agricultural gains is paramount. However, studies that relate variability in CO 2 and CH 4 emissions at large spatial scales are limited. We investigated three-year emissions of soil CO 2 and CH 4 from the primary wetland types of the Liaohe Delta, China, by focusing on a total wetland area of 3287 km 2 . One percent is Suaeda salsa , 24% is Phragmites australis , and 75% is rice. While S . salsa wetlands are under somewhat natural tidal influence, P . australis and rice are managed hydrologically for paper and food, respectively. Total C emissions from CO 2 and CH 4 from these wetland soils were 2.9 Tg C/year, ranging from 2.5 to 3.3 Tg C/year depending on the year assessed. Primary emissions were from CO 2 (~98%). Photosynthetic uptake of CO 2 would mitigate most of the soil CO 2 emissions, but CH 4 emissions would persist. Overall, CH 4 fluxes were high when soil temperatures were >18°C and pore water salinity <18 PSU. CH 4 emissions from rice habitat alone in the Liaohe Delta represent 0.2% of CH 4 carbon emissions globally from rice. With such a large area and interannual sensitivity in soil GHG fluxes, management practices in the Delta and similar wetlands around the world have the potential not only to influence local C budgeting, but also to influence global biogeochemical cycling.