Abstract

Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C) and greenhouse gas (GHG) exchanges is still limited. The aim of this study was to investigate the impact of contrasting mean water table levels (WTLs) on the annual C and GHG balances of restoration treatments with high (Res(H)) and low (Res(L)) WTL relative to an unrestored bare peat (BP) site. Measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in Res(H) relative to Res(L). Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in Res(L) compared to Res(H). However, the means of the measured net ecosystem CO2 exchanges (NEE) were not significantly different between Res(H) and Res(L). Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, Res(H), Res(L) and BP were C sources of 111, 103 and 268 g Cm-2 yr(-1) and had positive GHG balances of 4.1, 3.8 and 10.2 tCO(2) eq ha(-1) yr(-1), respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments 3 years following restoration. However, the C and GHG balances in Res(H) and Res(L) were considerably lower than in BP due to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative climate impacts of abandoned peat extraction areas.

Published in

Biogeosciences
2016, Volume: 13, number: 9, pages: 2637-2651
Publisher: COPERNICUS GESELLSCHAFT MBH

SLU Authors

• Peichl, Matthias

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Forest Science


Publication identifier

DOI: https://doi.org/10.5194/bg-13-2637-2016

Permanent link to this page (URI)

https://res.slu.se/id/publ/77897