title: Increase in carbon accumulation in a boreal peatland following a period of wetter climate and long-term decrease in nitrogen deposition.
abstract: Rates of peat growth and carbon (C) accumulation in a Sphagnum-dominated boreal peatland in south-east Norway were compared over two time periods each 17 yr long, that is, an earlier period from 1978 to 1995 and a recent period from 1995 to 2012. Our research was based on 109 peat cores. By using exactly the same study area and sampling protocols to obtain data for the two time periods, we were able to obtain a clear picture of the spatio-temporal patterns of peat accumulation. We show that peat growth and C accumulation were significantly higher in the recent than in the earlier time period. Interestingly, nitrogen (N) deposition was lower in the recent than in the earlier time period, while precipitation increased in the recent time period. Temperatures did not show any consistent trends over the time periods. Although our data do not allow assessment of the relative importance of declining N deposition vs increasing precipitation as drivers of peat accumulation, our results suggest that peatland C sequestration is not significantly inhibited by N pollution at current precipitation and N deposition levels.
authors: Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432, Ås, Norway.
authors: Simon
authors: S
authors: Utstøl-Klein
authors: Department of Botany, Natural History Museum, University of Oslo, PO Box 1172, Blindern, NO-0318, Oslo, Norway.
authors: Rune
authors: R
authors: Halvorsen
authors: Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432, Ås, Norway.
authors: Mikael
authors: M
authors: Ohlson
mesh_terms: D002244:Carbon / Q000378:metabolism*; D002980:Climate; D005843:Geography; D016014:Linear Models; D009584:Nitrogen / Q000378:metabolism*; D009664:Norway; D011891:Rain; D012987:Soil; D066188:Taiga; D013696:Temperature; D013997:Time Factors; D053833:Wetlands
chemical_list: D012987:Soil; D002244:Carbon; D009584:Nitrogen
keywords: Sphagnum; bog; hummock; ombrotrophic; peat growth; pine method