The University of Southampton
University of Southampton Institutional Repository

Modelling spatial distributions of Ceratium hirundnella and Mycrocystis in a small productive British lake

Modelling spatial distributions of Ceratium hirundnella and Mycrocystis in a small productive British lake
Modelling spatial distributions of Ceratium hirundnella and Mycrocystis in a small productive British lake
The short-term relationships between the spatial distributions of phytoplankton and the environmental conditions of Esthwaite Water, a small eutrophic lake in the English Lake District, UK, were examined using a hydrodynamic model. Spatial distributions of phytoplankton were simulated on two occasions the first, when the population was dominated by dinoflagellates; and the second, when the population was dominated by cyanobacteria.Vertical motility of the dinoflagellate Ceratium hirundinellaand buoyancy of the cyanobacteria Microcystis ssprm.were estimated as functions of irradiance. Water velocity fields were estimated through solving the 3-D Navier–Stokes equations on a finite-volume, unstructured non-orthogonal grid. Simulated circulation patterns of water and phytoplankton were similar to those obtained through field observations. Near-surface drift currents were initiated by wind stress, which then generated return currents along the seasonal thermocline. Aggregations of motile Ceratiumthat existed near the thermocline were pushed upwind by the deep return currents and accumulated at upwelling areas. In contrast, near-surface aggregations of Microcystiswere pushed downwind by the surface currents and accumulated at downwelling areas. Horizontal and vertical phytoplankton distributions resulted from the interaction between the vertical motility of the phytoplankton (dependent upon the light environment) and the velocity vectors at the depths at which the phytoplankton accumulated (dependent upon wind stress and morphometry). Modelling showed that phytoplankton motility and buoyancy greatly affect phytoplankton spatial distributions.
Esthwaite Water, dinoflagellates, cyanobacteria, spatial distributions, modelling
0018-8158
217-227
Hedger, R.
68efed4b-56cf-42a5-8033-02e854a4c9d1
Olsen, N.R.B.
c8099a1c-54b0-4571-9aea-c54afe87987d
George, D.
88cb4ac1-482d-4e6d-b642-cf321d5414a1
Malthus, T.J.
42dec45a-9314-4147-9cf6-029322bc1563
Atkinson, P.M.
aaaa51e4-a713-424f-92b0-0568b198f425
Hedger, R.
68efed4b-56cf-42a5-8033-02e854a4c9d1
Olsen, N.R.B.
c8099a1c-54b0-4571-9aea-c54afe87987d
George, D.
88cb4ac1-482d-4e6d-b642-cf321d5414a1
Malthus, T.J.
42dec45a-9314-4147-9cf6-029322bc1563
Atkinson, P.M.
aaaa51e4-a713-424f-92b0-0568b198f425

Hedger, R., Olsen, N.R.B., George, D., Malthus, T.J. and Atkinson, P.M. (2005) Modelling spatial distributions of Ceratium hirundnella and Mycrocystis in a small productive British lake. Hydrobiologia, 528 (1-3), 217-227. (doi:10.1007/s10750-004-2349-1).

Record type: Article

Abstract

The short-term relationships between the spatial distributions of phytoplankton and the environmental conditions of Esthwaite Water, a small eutrophic lake in the English Lake District, UK, were examined using a hydrodynamic model. Spatial distributions of phytoplankton were simulated on two occasions the first, when the population was dominated by dinoflagellates; and the second, when the population was dominated by cyanobacteria.Vertical motility of the dinoflagellate Ceratium hirundinellaand buoyancy of the cyanobacteria Microcystis ssprm.were estimated as functions of irradiance. Water velocity fields were estimated through solving the 3-D Navier–Stokes equations on a finite-volume, unstructured non-orthogonal grid. Simulated circulation patterns of water and phytoplankton were similar to those obtained through field observations. Near-surface drift currents were initiated by wind stress, which then generated return currents along the seasonal thermocline. Aggregations of motile Ceratiumthat existed near the thermocline were pushed upwind by the deep return currents and accumulated at upwelling areas. In contrast, near-surface aggregations of Microcystiswere pushed downwind by the surface currents and accumulated at downwelling areas. Horizontal and vertical phytoplankton distributions resulted from the interaction between the vertical motility of the phytoplankton (dependent upon the light environment) and the velocity vectors at the depths at which the phytoplankton accumulated (dependent upon wind stress and morphometry). Modelling showed that phytoplankton motility and buoyancy greatly affect phytoplankton spatial distributions.

Text
Hedger_et_al_Hyd_2004.pdf - Other
Restricted to Registered users only
Download (256kB)

More information

Published date: 2005
Keywords: Esthwaite Water, dinoflagellates, cyanobacteria, spatial distributions, modelling

Identifiers

Local EPrints ID: 15772
URI: http://eprints.soton.ac.uk/id/eprint/15772
ISSN: 0018-8158
PURE UUID: cdcd8ede-22bf-41ad-bfd3-9a09b81d874a

Catalogue record

Date deposited: 01 Jun 2005
Last modified: 15 Mar 2024 05:43

Export record

Altmetrics

Contributors

Author: R. Hedger
Author: N.R.B. Olsen
Author: D. George
Author: T.J. Malthus
Author: P.M. Atkinson

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.

×