DOI: 10.1002/2017JC013542
Scopus记录号: 2-s2.0-85041210704
论文题名: Nitrate Sources, Supply, and Phytoplankton Growth in the Great Australian Bight: An Eulerian-Lagrangian Modeling Approach
作者: Cetina-Heredia P. ; van Sebille E. ; Matear R.J. ; Roughan M.
刊名: Journal of Geophysical Research: Oceans
ISSN: 21699275
出版年: 2018
卷: 123, 期: 2 起始页码: 759
结束页码: 772
语种: 英语
英文关键词: chlorophyll
; Great Australian Bight
; Lagrangian
; nitrate fluxes
; nitrate sources
; phytoplankton growth
Scopus关键词: biogeochemistry
; chlorophyll
; concentration (composition)
; euphotic zone
; growth rate
; hydrodynamics
; mixed layer
; nitrate
; oceanic circulation
; phytoplankton
; primary production
; stratification
; Great Australian Bight
; Indian Ocean
英文摘要: The Great Australian Bight (GAB), a coastal sea bordered by the Pacific, Southern, and Indian Oceans, sustains one of the largest fisheries in Australia but the geographical origin of nutrients that maintain its productivity is not fully known. We use 12 years of modeled data from a coupled hydrodynamic and biogeochemical model and an Eulerian-Lagrangian approach to quantify nitrate supply to the GAB and the region between the GAB and the Subantarctic Australian Front (GAB-SAFn), identify phytoplankton growth within the GAB, and ascertain the source of nitrate that fuels it. We find that nitrate concentrations have a decorrelation timescale of ∼60 days; since most of the water from surrounding oceans takes longer than 60 days to reach the GAB, 23% and 75% of nitrate used by phytoplankton to grow are sourced within the GAB and from the GAB-SAFn, respectively. Thus, most of the nitrate is recycled locally. Although nitrate concentrations and fluxes into the GAB are greater below 100 m than above, 79% of the nitrate fueling phytoplankton growth is sourced from above 100 m. Our findings suggest that topographical uplift and stratification erosion are key mechanisms delivering nutrients from below the nutricline into the euphotic zone and triggering large phytoplankton growth. We find annual and semiannual periodicities in phytoplankton growth, peaking in the austral spring and autumn when the mixed layer deepens leading to a subsurface maximum of phytoplankton growth. This study highlights the importance of examining phytoplankton growth at depth and the utility of Lagrangian approaches. © 2017. 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/114618
Appears in Collections: 气候减缓与适应
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作者单位: Climate Change Research Centre, ARC Centre of Excellence for Climate System Science, UNSW Australia, Sydney, Australia; Department of Physics, Grantham Institute, Imperial College London, London, United Kingdom; Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands; CSIRO Marine Laboratories, CSIRO Marine and Atmospheric Research, Hobart, Australia; Regional and Coastal Oceanography Laboratory, School of Mathematics and Statistics, UNSW Australia, Sydney, Australia
Recommended Citation:
Cetina-Heredia P.,van Sebille E.,Matear R.J.,et al. Nitrate Sources, Supply, and Phytoplankton Growth in the Great Australian Bight: An Eulerian-Lagrangian Modeling Approach[J]. Journal of Geophysical Research: Oceans,2018-01-01,123(2)