The University of Southampton
University of Southampton Institutional Repository

Phytoplankton acclimation to changing light intensity in a turbulent mixed layer: A Lagrangian modelling study

Phytoplankton acclimation to changing light intensity in a turbulent mixed layer: A Lagrangian modelling study
Phytoplankton acclimation to changing light intensity in a turbulent mixed layer: A Lagrangian modelling study
A new individual-based plankton model is used to test the hypothesis that the timescale of photoacclimation of phytoplankton within the surface mixing layer of the ocean is slow relative to mixing, in which case the chlorophyll to carbon (Chl:C) ratio of individual cells shows little adjustment in response to changes in light environment driven by vertical displacement. Rates of photoacclimation are shown to be a strongly non-linear function of light intensity that depends on the balance of intrinsic chlorophyll synthesis at low irradiance versus increasing growth rate at high irradiance. Predicted photoacclimation was negligible for cells experiencing rates of turbulent mixing typical of the open ocean surface boundary layer (10−3 to 10-1 m2 s-1), in which case Chl:C is set by mean light intensity. The model was extended to incorporate a simple ecosystem of nutrient, phytoplankton, zooplankton and detritus and, using two-layer slab physics, used to study photoacclimation in a more realistic setting, the seasonal cycle of plankton dynamics at Ocean Weather Station India in the North Atlantic (59 °N, 20 °W). Results were remarkably similar when compared with an equivalent ecosystem model that used an Eulerian representation of phytoplankton, reinforcing our conclusion that mixing rates within the surface mixed layer of the ocean are typically too fast to permit photoacclimation by phytoplankton to ambient light.
Carbon to chlorophyll, Individual-based model, Lagrangian model, Marine ecosystem, Photoacclimation, Primary production
0304-3800
Tomkins, Melissa
ef72651d-dfd9-45d4-984f-3439f9fae456
Martin, Adrian P.
9d0d480d-9b3c-44c2-aafe-bb980ed98a6d
Nurser, A.j. George
2493ef9a-21e9-4d8b-9c32-08677e7e145a
Anderson, Thomas R.
dfed062f-e747-48d3-b59e-2f5e57a8571d
Tomkins, Melissa
ef72651d-dfd9-45d4-984f-3439f9fae456
Martin, Adrian P.
9d0d480d-9b3c-44c2-aafe-bb980ed98a6d
Nurser, A.j. George
2493ef9a-21e9-4d8b-9c32-08677e7e145a
Anderson, Thomas R.
dfed062f-e747-48d3-b59e-2f5e57a8571d

Tomkins, Melissa, Martin, Adrian P., Nurser, A.j. George and Anderson, Thomas R. (2020) Phytoplankton acclimation to changing light intensity in a turbulent mixed layer: A Lagrangian modelling study. Ecological Modelling, 417, [108917]. (doi:10.1016/j.ecolmodel.2019.108917).

Record type: Article

Abstract

A new individual-based plankton model is used to test the hypothesis that the timescale of photoacclimation of phytoplankton within the surface mixing layer of the ocean is slow relative to mixing, in which case the chlorophyll to carbon (Chl:C) ratio of individual cells shows little adjustment in response to changes in light environment driven by vertical displacement. Rates of photoacclimation are shown to be a strongly non-linear function of light intensity that depends on the balance of intrinsic chlorophyll synthesis at low irradiance versus increasing growth rate at high irradiance. Predicted photoacclimation was negligible for cells experiencing rates of turbulent mixing typical of the open ocean surface boundary layer (10−3 to 10-1 m2 s-1), in which case Chl:C is set by mean light intensity. The model was extended to incorporate a simple ecosystem of nutrient, phytoplankton, zooplankton and detritus and, using two-layer slab physics, used to study photoacclimation in a more realistic setting, the seasonal cycle of plankton dynamics at Ocean Weather Station India in the North Atlantic (59 °N, 20 °W). Results were remarkably similar when compared with an equivalent ecosystem model that used an Eulerian representation of phytoplankton, reinforcing our conclusion that mixing rates within the surface mixed layer of the ocean are typically too fast to permit photoacclimation by phytoplankton to ambient light.

Text
1-s2.0-S0304380019304259-main - Version of Record
Available under License Creative Commons Attribution.
Download (2MB)

More information

Accepted/In Press date: 11 December 2019
e-pub ahead of print date: 7 January 2020
Published date: 1 February 2020
Keywords: Carbon to chlorophyll, Individual-based model, Lagrangian model, Marine ecosystem, Photoacclimation, Primary production

Identifiers

Local EPrints ID: 437826
URI: http://eprints.soton.ac.uk/id/eprint/437826
ISSN: 0304-3800
PURE UUID: c3fbf967-1da1-4516-b7e7-bbbcc76358ed

Catalogue record

Date deposited: 19 Feb 2020 17:32
Last modified: 16 Mar 2024 06:29

Export record

Altmetrics

Contributors

Author: Melissa Tomkins
Author: Adrian P. Martin
Author: A.j. George Nurser
Author: Thomas R. Anderson

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×