气候变化领域集成服务门户(CCPortal): Mercury in Active-Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution

CCPortal

DOI	10.1029/2017GB005840
	Mercury in Active-Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution
	Olson C.; Jiskra M.; Biester H.; Chow J.; Obrist D.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	1058
结束页码	1073
卷号	32 期号:7
英文摘要	Tundra soils serve as major sources of mercury (Hg) input to the Arctic Ocean via river runoff and coastal erosion; yet little information is available on tundra soil Hg concentrations, pool sizes, origins, and dynamics. We present a detailed investigation of Hg in the active layer (upper ~100 cm subject to seasonal thaw) of tundra soils across 11 sites in Alaska. Soil Hg concentrations in organic horizons (151 ± 7 μg/kg) were in the upper range of temperate soil organic horizons, and concentrations in mineral horizons (98 ± 6 μg/kg) were much higher than in temperate soils. Soil Hg concentrations declined from inland to coastal sites, in contrast to a hypothesized northward increase expected because of proximity to coastal atmospheric mercury depletion events. Principle component analyses and elemental ratios results show that exogenic sources dominated over geogenic sources—in A-horizons (66 ± 4%) and mineral B-horizons (51 ± 1%). 14C age-dating suggested recent origins of Hg in surface soils but showed that mineral soils (more than 7,300 years old) must have accumulated atmospheric inputs across millennia leading to high soil concentrations and pools. We estimated a total Northern Hemisphere active-layer tundra soil Hg pool of 184 Gg (range of 136 to 274 Gg), suggesting a globally important Hg storage pool. Tundra soils are subject to seasonal thaw and freeze dynamics, thereby providing large inputs to rivers, lakes, and the Arctic Ocean. Understanding processes that mobilize Hg from tundra soils will be critical to understanding future Arctic wildlife and human Hg exposures. ©2018. American Geophysical Union. All Rights Reserved.
英文关键词	Alaska; Arctic; mercury; pollution; soils; tundra
语种	英语
scopus关键词	active layer; concentration (composition); mercury (element); Northern Hemisphere; pollutant source; soil horizon; soil pollution; spatial distribution; temperate environment; tundra soil; Alaska; Arctic; Arctic Ocean; United States
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129810
作者单位	Desert Research Institute, Reno, NV, United States; Geosciences Environment Toulouse, CNRS, Toulouse, France; Environmental Geochemistry, Technische Universität Braunschweig, Braunschweig, Germany; Department of Environmental, Earth and Atmospheric Sciences, University of Massachusetts, Lowell, MA, United States
推荐引用方式 GB/T 7714	Olson C.,Jiskra M.,Biester H.,et al. Mercury in Active-Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution[J],2018,32(7).
APA	Olson C.,Jiskra M.,Biester H.,Chow J.,&Obrist D..(2018).Mercury in Active-Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution.Global Biogeochemical Cycles,32(7).
MLA	Olson C.,et al."Mercury in Active-Layer Tundra Soils of Alaska: Concentrations, Pools, Origins, and Spatial Distribution".Global Biogeochemical Cycles 32.7(2018).