气候变化领域集成服务门户(CCPortal): Microbial processes in the weathering crust aquifer of a temperate glacier

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DOI	10.5194/tc-12-3653-2018
	Microbial processes in the weathering crust aquifer of a temperate glacier
	Christner B.C.; Lavender H.F.; Davis C.L.; Oliver E.E.; Neuhaus S.U.; Myers K.F.; Hagedorn B.; Tulaczyk S.M.; Doran P.T.; Stone W.C.
发表日期	2018
ISSN	19940416
卷号	12 期号:11
英文摘要	Incident solar radiation absorbed within the ablation zone of glaciers generates a shallow perched aquifer and seasonal icebound microbial habitat. During the melt seasons of 2014 and 2015, borehole investigations were used to examine the physical, geochemical, and microbiological properties in the near-surface ice and aquifer of the temperate Matanuska Glacier (south-central Alaska). Based on temperature, solar forcing, and ice optical properties, the dissipation of shortwave radiation promoted internal melting and the formation of a weathering crust with a maximum depth of ∼2 m. Boreholes into the weathering crust provided access to water percolating through the porous ice. The water had low ion concentrations (4-12 μS cm-1), was aerobic (12 mgO2 L-1), contained 200 to 8300 cellsmL-1, and harbored growing populations with estimated in situ generation times of 11 to 14 days. During the melt season, the upper 2m of ice experienced at least 3% of the surface photosynthetically active radiation flux and possessed a fractional water content as high as 10 %. Photosynthetic subsistence of biogeochemical reactions in the weathering crust ecosystem was supported by ex situ metabolic experiments and the presence of phototrophic taxa (cyanobacteria, golden and green algae) in the aquifer samples. Meltwater durations of ∼ 7.5 months coupled with the growth estimates imply biomass may increase by 4 orders of magnitude each year. Our results provide insight into how seasonal dynamics affect habitability of near-surface ice and microbial processes in a portion of the glacial biome poised to expand in extent with increasing global temperature and ablation season duration. © 2018 Author(s).
学科领域	ablation; aquifer; biogeochemistry; biome; concentration (composition); dissipation; glacier; meltwater; microbial activity; percolation; photosynthetically active radiation; seasonal variation; solar radiation; weathering; Alaska; Matanuska Glacier; United States; Chlorophyta; Cyanobacteria
语种	英语
scopus关键词	ablation; aquifer; biogeochemistry; biome; concentration (composition); dissipation; glacier; meltwater; microbial activity; percolation; photosynthetically active radiation; seasonal variation; solar radiation; weathering; Alaska; Matanuska Glacier; United States; Chlorophyta; Cyanobacteria
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119027
作者单位	Department of Microbiology and Cell Science, University of Florida, Biodiversity Institute, Gainesville, FL 32611, United States; Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States; Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, United States; Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803, United States; Sustainable Earth Research LLC, Anchorage, AK 99508, United States; Stone Aerospace, Del Valle, TX 78617, United States; Department of Biology, San Diego State University, San Diego, CA 92182, United States
推荐引用方式 GB/T 7714	Christner B.C.,Lavender H.F.,Davis C.L.,et al. Microbial processes in the weathering crust aquifer of a temperate glacier[J],2018,12(11).
APA	Christner B.C..,Lavender H.F..,Davis C.L..,Oliver E.E..,Neuhaus S.U..,...&Stone W.C..(2018).Microbial processes in the weathering crust aquifer of a temperate glacier.Cryosphere,12(11).
MLA	Christner B.C.,et al."Microbial processes in the weathering crust aquifer of a temperate glacier".Cryosphere 12.11(2018).