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标题：Enhancement of glacial solute fluxes in the proglacial zone of a polythermal glacier
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作者：J. L Wadham ; R. J. Cooper ; M. Tranter 等
期刊名称：Journal of Glaciology
印刷版ISSN：0022-1430
电子版ISSN：1727-5652
出版年度：2001
卷号：47
期号：158
页码：378-386
DOI：10.3189/172756501781832188
出版社：Cambridge University Press
摘要：Annual proglacial solute fluxes and chemical weathering rates at a polythermal high-Arctic glacier are presented. Bulk meltwater chemistry and discharge were monitored continuously at gauging stations located at the eastern and western margins of the glacier terminus and at “the Outlet”, 2.5 km downstream where meltwaters discharge into the fjord. Fluxes of non-snowpack HCO 3− , SO 42− , Ca 2 and Mg 2 increase by 30–47% between the glacier terminus and the Outlet, indicating that meltwaters are able to access and chemically weather efflorescent sulphates, carbonates and sulphides in the proglacial zone. Smaller increases in the fluxes of non-snowpack-derived Na , K and Si indicate that proglacial chemical weathering of silicates is less significant. En3hanced solute fluxes in the proglacial zone are mainly due to the chemical weathering of active-layer sediments. The P CO 2 of active-layer ground-waters is above atmospheric pressure. This implies that solute acquisition in the active layer involves no drawdown of CO 2 . The annual proglacial chemical weathering rate in 1999 is calculated to be 2600 meqΣ m −2 . This exceeds the chemical weathering rate for the glaciated part of the catchment (790 meqΣ m −2 ) by a factor of 3.3. Hence, the proglacial zone at Finster-walderbreen is identified as an area of high geochemical reactivity and a source of CO 2 .