Phytoplankton monitoring by high performance flow cytometry: A successful approach?

Abstract

Background: Regular phytoplankton monitoring in Dutch coastal waters is performed as an indicator of the ecological state of these waters. The monitoring program is focused on temporal and spatial changes of species composition and abundance. Flow cytometry has been introduced to provide additional information, to improve ecosystem understanding, and to increase the efficiency of analysis and reportage. Methods: Phytoplankton community abundance and composition were routinely determined by flow cytometry and microscopy at six locations in the North Sea over three annual cycles between 2000 and 2003. Supplementary measurements were also made for fluorescence (chlorophyll-a and other pigments) and, in combination with flow cytometric and microscopic data, were used to determine phytoplankton abundance and composition as a function of their size distribution. Real-time imaging of species was also used to identify species on the basis of their flow cytometric optical characteristics. Results: Flow cytometric analysis took 15 min on average. Analysis including data processing, and Web site reportage took less than 1 h. Phytoplankton concentrations (cells/ml), biomass (fluorescence/ml), and concentration of phycoerythrin-or phycocyanin-containing cells (cells/

Impact of Roundup on the marine microbial community, as shown by an in situ microcosm experiment

“…Beside genetic fingerprinting techniques, flow cytometry can also provide information about natural microbial community populations, and their abundances (Hofstraat et al, 1994;Jonker et al, 1995;Marie et al, 1999;Rutten et al, 2005). Toxicity assessment using flow cytometry was reported in studies involving either phytoplankton cultures (Cid et al, 1995(Cid et al, , 1996Lage et al, 2001;Stauber et al, 2005;Yu et al, 2007) or natural photosynthetic communities (de la Broise and Palenik, 2007).…”

Effects of elevated CO2 on phytoplankton community biomass and species composition during a spring Phaeocystis spp. bloom in the western English Channel

“…The FlowCam image capture was not used to enumerate Phaeocystis spp. colonies since the samples were preserved with lugol's iodine which is known to cause colony disaggregation (Rutten et al, 2005) which can cause an underestimation in group biomass. Flow cytometric analysis causes cleavage of cell aggregations through the sheer force of sheath fluid (Dubelaar and van der Reijden, 1995), and thus provides more accurate enumeration of single cells disaggregated from colonies.…”

High-resolution analysis of a North Sea phytoplankton community structure based on in situ flow cytometry observations and potential implication for remote sensing

“…This deep level of phytoplankton diversity resolution requirement is not needed in biogeochemical processes studies in which functionality is preferred to taxonomy (Le Quéré et al, 2005). In this context, most of the optical clusters could be described at the plankton functional type level because of some singular similarities combining abundance, size, pigments and structure proxies obtained from optical SFC variables (Chisholm et al, 1988;Veldhuis and Kraay, 2000;Rutten et al, 2005;Zubkov and Burkill, 2006). The Cytobuoy instrument used in this study was developed to identify phytoplankton cells from picophytoplankton up to large microphytoplankton with complex shapes, even those forming chains.…”

“…This technology has recently been adapted for the analysis of almost all the phytoplankton size classes and focuses on the resolution of phytoplankton community structure dynamics (Dubelaar et al, 1999;Olson et al, 2003;Sosik et al, 2003;Thyssen et al, 2008a, b). In parallel, algorithms applied to remote sensing data have been developed which are dedicated to characterizing phytoplankton groups, PFTs or size classes (Sathyendranath et al, 2004;Ciotti et al, 2006;Nair et al, 2008;Aiken et al, 2008;Kostadinov et al, 2009;Uitz et al, 2010;Moisan et al, 2012). One of these algorithms, PHYSAT, has provided a description of the dominant phytoplankton functional types (Le Quéré et al, 2005) for open waters on a global scale, leading to various studies concerning the PFT variability (Alvain et al, 2005(Alvain et al, , 2013Masotti et al, 2011;Demarcq et al, 2011;Navarro et al, 2014).…”