DOI: 10.1029/2019GB006308
论文题名: Arctic River Dissolved and Biogenic Silicon Exports—Current Conditions and Future Changes With Warming
作者: Carey J.C. ; Gewirtzman J. ; Johnston S.E. ; Kurtz A. ; Tang J. ; Vieillard A.M. ; Spencer R.G.M.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2020
卷: 34, 期: 3 语种: 英语
英文关键词: active layer
; biogenic deposit
; biogenic material
; coastal water
; concentration (composition)
; dissolved matter
; flux measurement
; future prospect
; global warming
; latitudinal gradient
; permafrost
; phytoplankton
; silicon
; solute transport
; Alaska
; Arctic
; United States
; Bacillariophyta
学科: Arctic
; biogenic
; climate change
; dissolved silica
; permafrost
; rivers
; silica
中文摘要: Silicon (Si) exports from terrestrial to marine systems can dictate phytoplankton species composition in Arctic coastal waters. Diatoms are often the dominant autotroph in Arctic waters, making Si an important control on Arctic marine primary productivity. Yet even as Arctic regions are among the fastest warming on Earth, we lack baseline knowledge on the magnitudes and controls of Arctic river Si exports. To address uncertainties in current and future Si behavior, we used a combination of field data and modeling to quantify daily yields of dissolved Si (DSi) and biogenic Si (BSi) from a 400 km space-for-time latitudinal gradient of seven basins across the boreal-Arctic transition in Alaska (United States) over the course of 2 years (2015–2016). Mean annual DSi concentrations (33–149 μM) and yields (13–49 kmol km−2 year−1) were significantly and positively correlated with mean basin active layer depth, indicating that permafrost thaw will likely increase DSi fluxes to Arctic coastal waters. Conversely, BSi concentrations (7–16 μM) and yields (2.6–4.5 kmol km−2 year−1) were more uniform across the seven basins, indicating that warming may not substantially alter BSi loads to coastal systems in the near future. Our data also indicate that climatic warming will advance the timing of Si delivery to coastal waters in the spring, although the ratios of Si to nitrogen in Arctic river exports will likely remain steady. These results highlight the important role of basin hydrology, largely driven by permafrost extent, as a key driver of Si exchange at the land-sea interface in the Arctic. © 2020. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160057
Appears in Collections: 气候变化与战略
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作者单位: Division of Math and Science, Babson College, Wellesley, MA, United States; The Ecosystem Center, Marine Biological Laboratory, Woods Hole, MA, United States; Department of Earth and Environment, Boston University, Boston, MA, United States; Department of Biology, Boston University, Boston, MA, United States; Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, United States; Institute of Marine Science, University of Auckland, Auckland, New Zealand
Recommended Citation:
Carey J.C.,Gewirtzman J.,Johnston S.E.,et al. Arctic River Dissolved and Biogenic Silicon Exports—Current Conditions and Future Changes With Warming[J]. Global Biogeochemical Cycles,2020-01-01,34(3)