The spatial distribution of different phytoplankton functional groups in a Mediterranean reservoir

Moreno-Ostos, Enrique; Cruz-Pizarro, L.; Basanta, Ana; George, D. G.

doi:10.1007/s10452-007-9087-1

Cited by 41 publications

(33 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our findings identified marked spatial variations during the development of the bloom, which was characterized by higher cell abundances in the middle and downstream parts of the reservoir. As in other studies (for example Hotto et al, 2007;Moreno-Ostos et al, 2008), this heterogeneous spatial distribution of Microcystis biomass might have been generated by greater cyanobacterial growth in areas where conditions for growth were better, or by displacement of the population by currents or winds, leading to an accumulation of a high cyanobacterial biomass in some areas. Some findings from the ITS genotyping suggested that both these processes were probably involved in the heterogeneous distribution of Microcystis biomass in the Grangent reservoir.…”

Section: Discussionmentioning

confidence: 61%

Spatiotemporal changes in the genetic diversity of a bloom-forming Microcystis aeruginosa (cyanobacteria) population

Briand¹,

et al. 2008

View full text Add to dashboard Cite

The variations in microcystin concentrations during cyanobacterial blooms in freshwater ecosystems appear to depend on numerous factors, which have still not been fully identified. To contribute to clarify the situation, we have developed a spatial sampling approach to determine the dynamics and genetic diversity of a bloom-forming population of Microcystis aeruginosa in a large French reservoir, and the variations in the proportions of microcystin-producing genotypes. We demonstrated that marked changes occurred in the internal transcribed spacer (ITS) genotype composition of the M. aeruginosa population during the development of the bloom. These changes led progressively to the selection of one dominant ITS genotype throughout the entire reservoir when the cell number reached its maximum. At the same time, we identified a decrease in the proportion of the mcyB þ genotype, and a significant negative correlation between this proportion and that of the dominant ITS genotype during the bloom. Thus, it appeared that favorable conditions for Microcystis cell growth led to the selection, within the Microcystis population, of a nonmicrocystin-producing genotype, whereas potentially microcystin-producing genotypes were dominant in this population before and after the bloom, when environmental conditions were less favorable for growth.

show abstract

Section: Discussionmentioning

confidence: 61%

Spatiotemporal changes in the genetic diversity of a bloom-forming Microcystis aeruginosa (cyanobacteria) population

Briand¹,

et al. 2008

View full text Add to dashboard Cite

show abstract

“…It has long been known that the spatial distribution of phytoplankton species is driven by interactions between physical and biological processes (Fietz et al, 2005;Hillmer et al, 2008) and that wind has an important role in these physical processes (George and Heaney, 1978;Schernewski et al, 2005;Moreno-Ostos et al, 2008;Alexander and Imberger, 2009;Pobel et al, in press). However, all existing knowledge was mainly based on the study of phytoplankton communities living in the well-mixed epilimnetic layer, the spatial distribution of which is affected by direct forcing by the wind.…”

Section: Discussionmentioning

confidence: 99%

Impact of internal waves on the spatial distribution of Planktothrix rubescens (cyanobacteria) in an alpine lake

et al. 2010

View full text Add to dashboard Cite

The vertical and horizontal distribution of the cyanobacterium, Planktothrix rubescens, was studied in a deep alpine lake (Lac du Bourget) in a 2-year monitoring program with 11 sampling points, and a 24-h survey at one sampling station. This species is known to proliferate in the metalimnic layer of numerous deep mesotrophic lakes in temperate areas, and also to produce hepatotoxins. When looking at the distribution of P. rubescens at the scale of the entire lake, we found large variations (up to 10 m) in the depth of the biomass peak in the water column. These variations were closely correlated to isotherm displacements. We also found significant variations in the distribution of the cyanobacterial biomass in the northern and southern parts of the lake. We used a physical modeling approach to demonstrate that two internal wave modes can explain these variations. Internal waves are generated by wind events, but can still be detected several days after the end of these events. Finally, our 24-h survey at one sampling point demonstrated that the V1H1 sinusoidal motion could evolve into nonlinear fronts. All these findings show that internal waves have a major impact on the distribution of P. rubescens proliferating in the metalimnic layer of a deep lake, and that this process could influence the growth of this species by a direct impact on light availability.

show abstract

“…Planktonic organisms are generally non-randomly distributed over a wide range of spatial scales and typically aggregate in complex three-dimensional structures which can be small-scale patches as well as systematic gradients (GEORGE and EDWARDS, 1976;GEORGE and HEANEY, 1978;REYNOLDS, 1993;GEORGE, 1993;MORENO-OSTOS et al, 2008a). Whilst phytoplankton spatial distribution patterns can be influenced by many physical, chemical and biological factors (GEORGE, 1993), the mesoscale distribution of phytoplankton is often 246 E. MORENO-OSTOS et al …”

Section: Introductionmentioning

confidence: 98%

“…Whilst phytoplankton spatial distribution patterns can be influenced by many physical, chemical and biological factors (GEORGE, 1993), the mesoscale distribution of phytoplankton is often a product of complex interactions between the hydrodynamics of the lake and the buoyant/sinking properties of phytoplankton (REYNOLDS, 2006;MORENO-OSTOS et al, 2008a;MORENO-OSTOS et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Spatial Heterogeneity of Cyanobacteria and Diatoms in a Thermally Stratified Canyon‐Shaped Reservoir

Moreno‐Ostos

Cruz-Pizarro

Basanta³

et al. 2009

International Review of Hydrobiology

Self Cite

View full text Add to dashboard Cite

Moreno-Ostos, E., Cruz-Pizarro, L., Basanta, A., George, D. G. (2009). Spatial Heterogeneity of Cyanobacteria and Diatoms in a Thermally Stratified Canyon-Shaped Reservoir. International Review of Hydrobiology, 94(3), 245-257.Phytoplankton communities in lakes and reservoirs are seldom homogeneously distributed but usually aggregate in patches and gradients. In this study we have combined the use of in vivo spectrofluorometry and acoustic Doppler current profiling to investigate the effect of water movements on the spatial distribution of cyanobacteria and diatoms in a thermally stratified reservoir in SW Spain. The distinctive canyon-shaped morphometry of the reservoir (El Gergal) favoured the development of a 'conveyor belt' pattern of circulation aligned with the long axis of the reservoir. Under non-regulated conditions, the spatial distribution of phytoplankton was almost entirely dependent on the interactions between advective transport and the buoyancy properties of the different functional groups of phytoplankton. The positively-buoyant cyanobacteria accumulated near the surface and were then transported downwind by the surface drift currents. In contrast, the negatively-buoyant diatoms sank in the water column and were transported upwind by the sub-surface return currents. When deep water was abstracted from the reservoir, these distribution patterns were modified. The results are discussed in relation to the problem of acquiring representative water samples from the reservoir and the application of a simple empirical model to optimize the location of the station used for routine cyanobacteria sampling on the reservoir.Peer reviewe

show abstract

The spatial distribution of different phytoplankton functional groups in a Mediterranean reservoir

Cited by 41 publications

References 38 publications

Spatiotemporal changes in the genetic diversity of a bloom-forming Microcystis aeruginosa (cyanobacteria) population

Spatiotemporal changes in the genetic diversity of a bloom-forming Microcystis aeruginosa (cyanobacteria) population

Impact of internal waves on the spatial distribution of Planktothrix rubescens (cyanobacteria) in an alpine lake

Spatial Heterogeneity of Cyanobacteria and Diatoms in a Thermally Stratified Canyon‐Shaped Reservoir

Contact Info

Product

Resources

About