Comparison of greenhouse gas fluxes and nitrogen budgets from an ombotrophic bog in Scotland and a minerotrophic sedge fen in Finland

Abstract

Northern peatlands cover approximately 4% of the global land surface area. Those peatlands will be particularly vulnerable to environmental and climate change and therefore it is important to investigate their total greenhouse gas (GHG) budgets, to determine the feedback on the climate. Nitrogen (N) is known to influence the GHG budget in particular by affecting the methane (CH4) balance. At two peatland sites in Scotland and Finland GHG fluxes of carbon dioxide (CO2), methane and nitrous oxide (N2O) and nitrogen fluxes were measured as part of the European project ‘NitroEurope’. The Scottish site, Auchencorth Moss, was a GHG sink of −321, −490 and −321 g CO2 eq m−2 year−1 in 2006, 2007 and 2008, respectively, with CO2 as the dominating GHG. In contrast, the dominating GHG at the Finnish site, Lompolojänkkä, was CH4, resulting in the site being a net GHG source of +485 and +431 g CO2 eq m−2 year−1 in 2006 and 2007, respectively. Therefore, Auchencorth Moss had a negative global warming potential (GWP) whilst Lompolojänkkä had a positive GWP over the investigated time period. Initial results yielded a positive N budget for Lompolojänkkä of 7.1 kg N ha−1 year−1, meaning the site was gaining nitrogen, and a negative N budget for Auchencorth Moss of −2.4 kg N ha year−1, meaning the site was losing nitrogen.

Carbon balance of UK peatlands: current state of knowledge and future research challenges

“…Methane emissions from the land surface, measured using chambers in 2006-2008, are unusually low at Auchencorth Moss compared to other peatland sites (Dinsmore et al 2009b, Drewer et al 2010. This is likely to be because site conditions (low water table, absence of surface bogpool systems) do not encourage methane production.…”

“…The majority of the catchment is used for lowintensity sheep grazing with a small area of peat extraction in the southwest corner. The vegetation consists of a patchy mix of grasses and sedges covering a primarily Sphagnum base layer on a typical peatland hummock/ hollow microtopography; mean annual precipitation (2002)(2003)(2004)(2005)(2006)(2007)(2008) and temperature are 1155 mm and 10°C, respectively (Drewer et al 2010) The catchment drains through a series of natural tributaries and overgrown (>100 yr old) drainage ditches into the main stream, the Black Burn.…”

Sensitivity model study of regional mercury dispersion in the atmosphere

“…At the GB48 site the disagreement between the models and observations can be attributed to local effects, as suggested by Drewer et al (2010) in their study of greenhouse gas fluxes at the site. In fact this site is located in a peat bog, and the observed TGM values are very different from sites at similar latitudes such as DK01, Faerøerne, and IE31, Mace Head, where the annual average TGM concentrations were 1.56 and 1.49 ng m −3 , respectively, and the models are able to reproduce the observations.…”

Water soluble aerosols and gases at a UK background site – Part 1: Controls of PM<sub>2.5</sub> and PM<sub>10</sub> aerosol composition

“…Auchencorth Moss has been a long-term monitoring site for a number of trace gases including NH 3 , SO 2 and CO 2 (Famulari et al, 2010;Drewer et al, 2010;Flechard and Fowler, 1998). The site belongs to a number of UK national networks including the UK Defra Automatic urban and rural network (AURN), UK Acid gas and aerosol network (AGANet), UK National Ammonia Monitoring Network (NAMN), UK Precip-Net (bi-weekly bulk composition), UK PAH Network, UK Automatic Hydrocarbon Monitoring Network, UK Black Carbon Network and UK Toxic Organic MicroPollutants (TOMPS) network.…”