The relationship between cell carbon and cell volume in freshwater algal species used in zooplanktonic studies

Rocha, Odete; Duncan, A.

doi:10.1093/plankt/7.2.279

Cited by 238 publications

(149 citation statements)

References 7 publications

Supporting

Mentioning

140

Contrasting

Unclassified

Order By: Relevance

“…Phytoplankton biovolumes were estimated from measurements of 20-30 cells of each species using image analysis (inverted microscope Axio Observer A1, Zeiss; highresolution microscopy camera Axiocam HRc, Zeiss). Cell volume was calculated according to Carrillo et al (1995), and converted to phytoplankton carbon using the conversion factors reported by Rocha and Duncan (1985). Bacterial abundance (BA) was determined by the 4 ,6-diamidino-2-phenylindole (DAPI) direct-count method described by Porter and Feig (1980).…”

Section: Analysis Biological Variablesmentioning

confidence: 99%

Synergistic effects of UVR and simulated stratification on commensalistic phytoplankton–bacteria relationship in two optically contrasting oligotrophic Mediterranean lakes

et al. 2015

View full text Add to dashboard Cite

Abstract. An indirect effect of global warming is a reduction in the depth of the upper mixed layer (UML) causing organisms to be exposed to higher levels of ultraviolet (UVR, 280-400 nm) and photosynthetically active radiation (PAR, 400-700 nm). This can affect primary and bacterial production as well as the commensalistic phytoplankton-bacteria relationship. The combined effects of UVR and reduction in the depth of the UML were assessed on variables related to the metabolism of phytoplankton and bacteria, during in situ experiments performed with natural pico-and nanoplankton communities from two oligotrophic lakes with contrasting UVR transparency (high-UVR versus low-UVR waters) of southern Spain. The negative UVR effects on epilimnetic primary production (PP) and on heterotrophic bacterial production (HBP), intensified under increased stratification, were higher in the low-UVR than in the high-UVR lake, and stronger on the phytoplanktonic than on the heterotrophic bacterial communities. Under UVR and increased stratification, the commensalistic phytoplankton-bacteria relationship was strengthened in the high-UVR lake where excretion of organic carbon (EOC) rates exceeded the bacterial carbon demand (BCD; i.e., BCD : EOC(%) ratio < 100). This did not occur in the low-UVR lake (i.e., BCD : EOC(%) ratio > 100). The greater UVR damage to phytoplankton and bacteria and the weakening of their commensalistic interaction found in the low-UVR lake indicates that these ecosystems would be especially vulnerable to UVR and increased stratification as stressors related to global climate change. Thus, our findings may have important implications for the carbon cycle in oligotrophic lakes of the Mediterranean region.

show abstract

Section: Analysis Biological Variablesmentioning

confidence: 99%

Synergistic effects of UVR and simulated stratification on commensalistic phytoplankton–bacteria relationship in two optically contrasting oligotrophic Mediterranean lakes

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Calculation of cell volume was undertaken by mean cell size with the use of the most appropriate geometric form, which corresponds to the sphere formula (Hillebrand et al, 1999). TOC was calculated by C = 0.1204.V 1.051 (C = carbon content in pg.cell -1 ; V = cell volume) using regression according to Rocha and Duncan (1985).…”

Section: Growthmentioning

confidence: 99%

Effects of some parameters in upscale culture of Haematococcus pluvialis Flotow

2013

View full text Add to dashboard Cite

Growth rate and medium parameters between two bench scale volumes (13-L and 250-L) were compared. Experiments were maintained batch mode and culture parameters were periodically measured during a 13-day period. Culture growth during the cultivation of algae Haematococcus pluvialis was determined qualitatively by cell counting, optical density, dry weight, ash content, amount of chlorophyll-a, total organic carbon content and by direct measuring of medium nutrients and some abiotic aspects. Vegetative cell growth was higher when cultured in 13-L with 1.33 x 10 5 cells.mL -1 on the 12 th day than when cultured in 250-L. Significant difference (p < 0.05) in the biology and water culture of H. pluvialis, with the exception of dry weight, ash, nitrite and ammonia, was reported between the volumes. Data obtained in current study for the upscale culture maintenance of H. pluvialis in laboratory conditions shows that it should be undertaken in a 13-L volume due to a greater time span of cells in a vegetative state, greater cell density, lipids and chlorophyll-a contents. Light was of paramount importance on the direct performance of H. pluvialis on the algal biological conditions. Keywords: biological aspects, growth, nutritional content, microalgae. Efeito de alguns parâmetros no cultivo em larga escala de Haematococcus pluvialis Flotow ResumoForam avaliadas a taxa de crescimento e condições do meio de cultura em volumes de 13-L e 250-L em sistema estático, durante o período de 13 dias para a microalga Haematococcus pluvialis. Foi determinada qualitativamente a contagem de células, densidade, peso seco, teor de cinzas, clorofila-a, teor de carbono orgânico total e avaliação de nutrientes e fatores abióticos do meio de cultura. O crescimento foi mais elevado em volume de 13-L com 1,33 x 10 5 células.mL -1 no décimo segundo dia, do que em volume de 250-L. Em relação ao meio de cultivo e aspectos biológicos de H. pluvialis, foram observadas diferenças significativas (p < 0,05) entre os dois volumes com exceção do peso seco, cinzas, nitrito e amônia. Para cultivo em larga escale de H. pluvialis é recomendado nestas condições laboratoriais, o volume de 13-L devido ao maior tempo das células em estado vegetativo, maior densidade celular e elevados teores de lipídios e clorofila-a. A luz interferiu diretamente nas condições biológicas de H. pluvialis. Palavras-chave: aspectos biológicos, crescimento, conteúdo nutricional, microalga.

show abstract

“…Biovolume conversion factors were calculated using approximations to geometrical shapes (Straškrabová et al 1999, this issue). The specific carbon content was calculated from C = 0.1204V 1.051 using the regression after Rocha & Duncan (1985).…”

Section: Phytoplanktonmentioning

confidence: 99%

Seasonal dynamics and phytoplankton diversity in high mountain lakes (Jöri lakes, Swiss Alps)

Hinder¹,

Gabathuler²,

Steiner³

et al. 1999

J Limnol

View full text Add to dashboard Cite

show abstract

The relationship between cell carbon and cell volume in freshwater algal species used in zooplanktonic studies

Cited by 238 publications

References 7 publications

Synergistic effects of UVR and simulated stratification on commensalistic phytoplankton–bacteria relationship in two optically contrasting oligotrophic Mediterranean lakes

Synergistic effects of UVR and simulated stratification on commensalistic phytoplankton–bacteria relationship in two optically contrasting oligotrophic Mediterranean lakes

Effects of some parameters in upscale culture of Haematococcus pluvialis Flotow

Seasonal dynamics and phytoplankton diversity in high mountain lakes (Jöri lakes, Swiss Alps)

Contact Info

Product

Resources

About