期刊
JOURNAL OF MARINE SYSTEMS
卷 70, 期 3-4, 页码 248-262出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.jmarsys.2006.07.008
关键词
phytoplankton motility; tidal mixing; shelf sea; phototaxis; thermocline; turbulence modelling; Lagrangian modelling
资金
- Natural Environment Research Council [NE/C516079/1, pol010006] Funding Source: researchfish
- NERC [pol010006] Funding Source: UKRI
We investigate a role for vertical migration in stratified coastal water, where the swimming speed is generally significantly less than the typical turbulent fluctuations in a tidally-mixed bottom layer. In our modelling approach we use a k-epsilon turbulence model to describe the physical forcing, a Lagrangian random walk model to describe the vertical displacement of individual cells in response to turbulence and due to cell motility, and a phytoplankton growth model to direct the swimming behaviour of the phytoplankton according to their light and nutrient requirements. The model results show how the cells form a stable subsurface chlorophyll maximum (SCM) at the base of the thermocline where episodic tidal turbulence causes erosion of part of the SCM biomass into the bottom mixed layer (BML). We then focus on the question of whether an ability to swim (weakly, compared to typical bottom layer turbulent intensities) provides any advantage by allowing return to the SCM. Our results show that tidal turbulence in the BML helps both motile and neutrally-buoyant cells by periodically pushing them into the base of the thermocline. Motile cells then have the advantage that they can swim further into the thermocline towards higher light which also reduces the likelihood of being remixed back into the BML. (C) 2007 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据