We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Carbon isotope evidence for recent climate-related enhancement of CO<sub>2</sub> assimilation and peat accumulation rates in Antarctica.
- Authors
Royles, Jessica; Ogée, Jérôme; Wingate, Lisa; Hodgson, Dominic A.; Convey, Peter; Griffiths, Howard
- Abstract
Signy Island, maritime Antarctic, lies within the region of the Southern Hemisphere that is currently experiencing the most rapid rates of environmental change. In this study, peat cores up to 2 m in depth from four moss banks on Signy Island were used to reconstruct changes in moss growth and climatic characteristics over the late Holocene. Measurements included radiocarbon dating (to determine peat accumulation rates) and stable carbon isotope composition of moss cellulose (to estimate photosynthetic limitation by CO2 supply and model CO2 assimilation rate). For at least one intensively 14C-dated Chorisodontium aciphyllum moss peat bank, the vertical accumulation rate of peat was 3.9 mm yr−1 over the last 30 years. Before the industrial revolution, rates of peat accumulation in all cores were much lower, at around 0.6-1 mm yr−1. Carbon-13 discrimination (Δ), corrected for background and anthropogenic source inputs, was used to develop a predictive model for CO2 assimilation. Between 1680 and 1900, there had been a gradual increase in Δ, and hence assimilation rate. Since 1800, assimilation has also been stimulated by the changes in atmospheric CO2 concentration, but a recent decline in Δ (over the past 50-100 years) can perhaps be attributed to documented changes in temperature and/or precipitation. The overall increase in CO2 assimilation rate (13C proxy) and enhanced C accumulation (14C proxy) are consistent with warmer and wetter conditions currently generating higher growth rates than at any time in the past three millennia, with the decline in Δ perhaps compensated by a longer growing season.
- Subjects
SIGNY Island (South Orkney Islands); SOUTHERN Hemisphere; ANTARCTICA; CARBON isotopes; GLOBAL environmental change; HOLOCENE Epoch; CELLULOSE
- Publication
Global Change Biology, 2012, Vol 18, Issue 10, p3112
- ISSN
1354-1013
- Publication type
Article
- DOI
10.1111/j.1365-2486.2012.02750.x