Back to Search
Start Over
Flooding-related increases in CO2 and N2O emissions from a temperate coastal grassland ecosystem.
- Source :
- Biogeosciences; 2017, Vol. 14 Issue 10, p2611-2626, 16p, 2 Charts, 7 Graphs, 1 Map
- Publication Year :
- 2017
-
Abstract
- Given their increasing trend in Europe, an understanding of the role that flooding events play in carbon (C) and nitrogen (N) cycling and greenhouse gas (GHG) emissions will be important for improved assessments of local and regional GHG budgets. This study presents the results of an analysis of the CO<subscript>2</subscript> and N<subscript>2</subscript>O fluxes from a coastal grassland ecosystem affected by episodic flooding that was of either a relatively short (SFS) or long (LFS) duration. Compared to the SFS, the annual CO<subscript>2</subscript> and N<subscript>2</subscript>O emissions were 1.4 and 1.3 times higher at the LFS, respectively. Mean CO<subscript>2</subscript> emissions during the period of standing water were 144±18.18 and 111±9.51 mg CO<subscript>2</subscript>-Cm<superscript>-2 </superscript>h<superscript>-1</superscript>, respectively, for the LFS and SFS sites. During the growing season, when there was no standing water, the CO<subscript>2</subscript> emissions were significantly larger from the LFS (244±24.88 mgCO<subscript>2</subscript>-Cm<superscript>-2 </superscript>h<superscript>-1</superscript>/ than the SFS (183±14.90 mgCO<subscript>2</subscript>-Cm<superscript>-2 </superscript>h<superscript>-1</superscript>/. Fluxes of N<subscript>2</subscript>O ranged from -0.37 to 0.65 mgN2O-Nm<superscript>-2 </superscript>h<superscript>-1 </superscript>at the LFS and from -0.50 to 0.55 mgN2O-Nm<superscript>-2 </superscript>h<superscript>-1 </superscript>at the SFS, with the larger emissions associated with the presence of standing water at the LFS but during the growing season at the SFS. Overall, soil temperature and moisture were identified as the main drivers of the seasonal changes in CO<subscript>2</subscript> fluxes, but neither adequately explained the variations in N<subscript>2</subscript>O fluxes. Analysis of total C, N, microbial biomass and Q10 values indicated that the higher CO<subscript>2</subscript> emissions from the LFS were linked to the flooding-associated influx of nutrients and alterations in soil microbial populations. These results demonstrate that annual CO<subscript>2</subscript> and N<subscript>2</subscript>O emissions can be higher in longer-term flooded sites that receive significant amounts of nutrients, although this may depend on the restriction of diffusional limitations due to the presence of standing water to periods of the year when the potential for gaseous emissions are low. [ABSTRACT FROM AUTHOR]
- Subjects :
- FLOODS
CARBON dioxide
GREENHOUSE gases
ECOLOGY
GRASSLANDS
Subjects
Details
- Language :
- English
- ISSN :
- 17264170
- Volume :
- 14
- Issue :
- 10
- Database :
- Complementary Index
- Journal :
- Biogeosciences
- Publication Type :
- Academic Journal
- Accession number :
- 123379650
- Full Text :
- https://doi.org/10.5194/bg-14-2611-2017