DOI: 10.1016/j.palaeo.2013.09.009
论文题名: Recent increase in peatland carbon accumulation in a thermokarst lake basin in Southwestern Alaska
作者: Klein E.S. ; Yu Z. ; Booth R.K.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2013
卷: 392 起始页码: 186
结束页码: 195
语种: 英语
英文关键词: Paleoecology
; Paleohydrology
; Peatland carbon accumulation
; Southwestern Alaska
; Testate amoebae
; Thermokarst basin
英文摘要: Drained thermokarst lake basins cover large areas of northern high latitude lowlands. However, the importance of peat accumulated in these drained basins to carbon (C) cycling is poorly understood. Results are presented here from a permafrost sediment core aimed at investigating site history, lake drainage, apparent carbon accumulation, and paleohydrology in a thermokarst basin on the Yukon Kuskokwim Delta in southwestern Alaska. The results show that a thermokarst lake existed for about 2300years before it drained and a peatland established in the early 1600s. Average apparent C accumulation rate (CAR) was 12gC/m2/yr over the 2300years before lake drainage, but increased to 120gC/m2/yr following peatland initiation. After transitioning to a Sphagnum-dominated peatland at ~1700AD, CAR reduced gradually before more than doubling from the mid-1970s to the early 1980s. This abrupt increase in CAR was possibly in response to a Pacific climate regime shift in the late 1970s, a transition characterized by a nearly 1.5°C increase in regional average annual temperature. Even after considering the differential decay of recent peat, there was an increase in C accumulation after 1977. Reconstructed water-table depths from subfossil testate amoebae show little change throughout the past three centuries, but there was a pronounced shift in testate amoeba composition after the 1977 temperature change (e.g., absence of Phryganella acropodia type and increase in Hyalosphenia elegans). If the results from peatlands in other drained thermokarst lake basins are consistent with the results from this study, then the C accumulated in these vegetated drained basins under current warming might help offset some of the C released from thawing permafrost and thermokarst features in northern regions. © 2013 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69534
Appears in Collections: 过去全球变化的重建
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作者单位: Department of Earth and Environmental Sciences, Lehigh University, 1 West Packer Avenue, Bethlehem, PA 18015, United States; Environment and Natural Resource Institute, University of Alaska Anchorage, Anchorage, AK 99508, United States
Recommended Citation:
Klein E.S.,Yu Z.,Booth R.K.. Recent increase in peatland carbon accumulation in a thermokarst lake basin in Southwestern Alaska[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2013-01-01,392