气候变化领域集成服务门户(CCPortal): Effects of changing permafrost conditions on hydrological processes and fluvial fluxes

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DOI	10.1016/j.earscirev.2019.02.018
	Effects of changing permafrost conditions on hydrological processes and fluvial fluxes
	Lafrenière M.J.; Lamoureux S.F.
发表日期	2019
ISSN	00128252
起始页码	212
结束页码	223
卷号	191
英文摘要	This paper reviews the impacts of permafrost change on hydrological and related hydrochemical, particulate and organic fluxes in small Arctic catchments. While the emphasis is directed at High Arctic systems, literature and recent developments from other Arctic regions are also included. Hydrological change, particularly a shift from nival (snowmelt) dominance to increasing pluvial (rainfall) runoff contributions has important consequences for the timing and magnitude of hydrological fluxes. A key distinction is made between thermal perturbation, where changing melt season thaw conditions result in deep thaw with minimal geomorphic or surface hydrological effects, in contrast to physical perturbation, where permafrost change results in some form of thermokarst or physical disturbance such as mass movement or enhanced erosion. The latter disturbances are commonly expressed as localized thermo erosional gullies, active layer detachments and retrogressive thaw slumps. Results from recent research emphasise the importance of hydrological connectivity in terms of the downstream effect of a particular permafrost perturbation. Well-connected systems, either at the surface as channelized flows, or in the subsurface, through new or altered active layer flow pathways, result in substantial changes in downstream fluvial fluxes. Surface hydrological connectivity of localized permafrost disturbances increases transport of suspended sediment and particulate organic matter, the latter of which is often old and comparatively labile. Exposed ice in retrogressive thaw slumps sustains discharge during the melt season, further increasing fluxes. Thermal perturbation holds a substantially greater potential downstream impact due to widespread mobilization of solutes and dissolved organic carbon and nitrogen, and several studies point to rapid microbial alteration of carbon and inorganic nitrogen transformation in the shallow subsurface. Collectively, these results point to altered runoff, sediment transport and hydrochemical fluxes with spatial and hydrological controls. © 2019 Elsevier B.V.
关键词	Active layer detachments Climate change Dissolved organic matter Hydrochemical fluxes Particulate fluxes Permafrost hydrology
英文关键词	active layer; climate change; dissolved organic matter; fluvial deposit; hydrology; permafrost; sediment transport; suspended sediment; thermokarst
语种	英语
来源期刊	Earth Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203470
作者单位	Department of Geography and Planning, Queen's University, Kingston, ON K7L 3N6, Canada
推荐引用方式 GB/T 7714	Lafrenière M.J.,Lamoureux S.F.. Effects of changing permafrost conditions on hydrological processes and fluvial fluxes[J],2019,191.
APA	Lafrenière M.J.,&Lamoureux S.F..(2019).Effects of changing permafrost conditions on hydrological processes and fluvial fluxes.Earth Science Reviews,191.
MLA	Lafrenière M.J.,et al."Effects of changing permafrost conditions on hydrological processes and fluvial fluxes".Earth Science Reviews 191(2019).