Carbon accumulation in a permafrost polygon peatland: steady long-term rates in spite of shifts between dry and wet conditions

CORC > 成都山地灾害与环境研究所 > 中国科学院水利部成都山地灾害与环境研究所 > 山地表生过程与生态调控重点实验室

	Carbon accumulation in a permafrost polygon peatland: steady long-term rates in spite of shifts between dry and wet conditions
	Gao, Yang1,2 ; Couwenberg, John 2
刊名	GLOBAL CHANGE BIOLOGY
	2015-02-01
卷号	21 期号:2 页码:803-815
关键词	carbon accumulation dwarf shrubs ice-wedge polygon NE Siberia palaeo-temperature tundra vegetation development
ISSN号	1354-1013
通讯作者	Couwenberg, John
英文摘要	Ice-wedge polygon peatlands contain a substantial part of the carbon stored in permafrost soils. However, little is known about their long-term carbon accumulation rates (CAR) in relation to shifts in vegetation and climate. We collected four peat profiles from one single polygon in NE Yakutia and cut them into contiguous 0.5cm slices. Pollen density interpolation between AMS C-14 dated levels provided the time span contained in each of the sample slices, which - in combination with the volumetric carbon content - allowed for the reconstruction of CAR over decadal and centennial timescales. Vegetation representing dry palaeo-ridges and wet depressions was reconstructed with detailed micro- and macrofossil analysis. We found repeated shifts between wet and dry conditions during the past millennium. Dry ridges with associated permafrost growth originated during phases of (relatively) warm summer temperature and collapsed during relatively cold phases, illustrating the important role of vegetation and peat as intermediaries between ambient air temperature and the permafrost. The average long-term CAR across the four profiles was 10.6 +/- 5.5g Cm(-2)yr(-1). Time-weighted mean CAR did not differ significantly between wet depression and dry ridge/hummock phases (10.6 +/- 5.2g Cm(-2)yr(-1) and 10.3 +/- 5.7g Cm(-2)yr(-1), respectively). Although we observed increased CAR in relation to warm shifts, we also found changes in the opposite direction and the highest CAR actually occurred during the Little Ice Age. In fact, CAR rather seems to be governed by strong internal feedback mechanisms and has roughly remained stable on centennial time scales. The absence of significant differences in CAR between dry ridge and wet depression phases suggests that recent warming and associated expansion of shrubs will not affect long-term rates of carbon burial in ice-wedge polygon peatlands.
WOS标题词	Science & Technology ; Life Sciences & Biomedicine
类目[WOS]	Biodiversity Conservation ; Ecology ; Environmental Sciences
研究领域[WOS]	Biodiversity & Conservation ; Environmental Sciences & Ecology
关键词[WOS]	ACTIVE LAYER ; SIBERIAN TUNDRA ; SHRUB EXPANSION ; CLIMATE ; THAW ; ECOSYSTEMS ; VEGETATION ; CALIBRATION ; INCREASES ; RESPONSES
收录类别	SCI
语种	英语
WOS记录号	WOS:000348652400025
内容类型	期刊论文
源URL	[http://ir.imde.ac.cn/handle/131551/9589]
专题	成都山地灾害与环境研究所_山地表生过程与生态调控重点实验室
作者单位	1.Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu, Sichuan, Peoples R China 2.Ernst Moritz Arndt Univ Greifswald, Inst Bot & Landscape Ecol, Greifswald, Germany
推荐引用方式 GB/T 7714	Gao, Yang,Couwenberg, John. Carbon accumulation in a permafrost polygon peatland: steady long-term rates in spite of shifts between dry and wet conditions[J]. GLOBAL CHANGE BIOLOGY,2015,21(2):803-815.
APA	Gao, Yang,&Couwenberg, John.(2015).Carbon accumulation in a permafrost polygon peatland: steady long-term rates in spite of shifts between dry and wet conditions.GLOBAL CHANGE BIOLOGY,21(2),803-815.
MLA	Gao, Yang,et al."Carbon accumulation in a permafrost polygon peatland: steady long-term rates in spite of shifts between dry and wet conditions".GLOBAL CHANGE BIOLOGY 21.2(2015):803-815.