Description
The monitoring at the SOMLIT-Astan station (north of Roscoff - France, Western English Channel) was designed to study long term changes in phytoplankton communities in a global change context (diversity, phenology). Phytoplankton communities are monitored twice a month according to the SOMLIT monitoring program (Service d'Observation en Milieu Littoral : http://somlit.epoc.u-bordeaux1.fr/fr/), national network performing measurements of hydrological parameters. SOMLIT-Astan phytoplankton monitoring contains :1/ Microphytoplankton - Species abundances (according to Utermöhl method microphytoplankton abundances - number of cells per liter) ; 2/ Microphytoplankton - Species semi-quantitative occurrences (20µm net haul, occurrence code : "1" present, "2" numerous, "3"dominant) ; 3/ Fonctionnal groups abundances (Flowcytometry - number of cells per milliliter) : pico-, nano-phytoplankton, heterotrophic and autotrophic bacteria. The datasets that are provided include only occurrence data determined through methods 1 and 2. Flow cytometry is thus not included.
Data Records
The data in this sampling event resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 884 records.
2 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.
This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.
Versions
The table below shows only published versions of the resource that are publicly accessible.
How to cite
Researchers should cite this work as follows:
Rigaut-Jalabert F, Simon N, Hoebeke M (2019): Long-term monitoring of the phytoplankton at the SOMLIT-Astan Station in the Western English Channel from 2000 to present. v1. Dataset/Samplingevent. https://doi.org/10.21411/7g10-dr41
Rights
Researchers should respect the following rights statement:
This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC 4.0) License.
GBIF Registration
This resource has not been registered with GBIF
Keywords
Phytoplankton; Biodiversity; Samplingevent
Contacts
- Metadata Provider ●
- Originator ●
- Point Of Contact
http://orcid.org/0000-0002-5311-658X
- Originator
- Originator
Geographic Coverage
SOMLIT-Astan - http://marineregions.org/mrgid/5372
| Bounding Coordinates | South West [48.778, -3.983], North East [48.778, -3.983] |
|---|
Taxonomic Coverage
Phytoplankton identifications and quantifications are made under inverted light microscope (at maximum magnification x400). Flowcytometry allowed to determine and quantifiy functionnal groups of pico-, nano-phytoplankton, heterotrophic and autotrophic bacteria.
| Kingdom | Bacteria |
|---|---|
| Phylum | Cyanobacteria, Cryptophyta, Haptophyta, Myzozoa, Ochrophyta, Chlorophyta, Rhodophyta, Euglenophyta |
Temporal Coverage
| Formation Period | 2000 to present |
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Sampling Methods
Different types of phytoplankton samples are collected at each sampling date. For qualitative analysis, under microscope (species semi-quantitative occurrences), net samples are collected using a 20µm nylon mesh cone towed during 3 minutes in subsurface. For quantitative analysis, under microscope and with a flow cytometeter (species and fonctionnal groups abundances), seawater samples are collected at 1m depth using a 5 liters Niskin bottle. For flow cytometry an additionnal sample is collected at -60m depth.
| Study Extent | From 2000, samples at SOMLIT-Astan station (60m depth, 48°46’18’’N-3° 58’ 6’’W) have been collected twice a month during the highest neap tide, along with samples collected in the frame of the SOMLIT monitoring program (Service d’Observation du Milieu Littoral, http://somlit.epoc.u-bordeaux1.fr/fr/) |
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Method step description:
- Microphytoplankton - Species abundances Seawater samples are collected at 1m depth using a 5 liters Niskin bottle. From 2000 to 2015, one hundred to 250 mL subsamples are were fixed with acid Logol's solution iodine according to Sournia (1978) back to the lab and stored in dark conditions at room temperature until analysis. From 2016, 250mL subsamples are fixed immediately after sampling with acid Lugol's solution iodine and stored at 4°C until analysis. For analysis, a sub-sample of lugol preserved water was gently poured into a 50 mL composite settling chamber (HYDRO-BIOS, Kiel), according to the standard Utermöhl settlement method described in Sournia (1978). Quantitative analyses based on the examination of lugol preserved samples were performed between 15 days and up to 1 year after sampling. Cell counts for either the whole chamber, or half a chamber, were obtained after sedimentation, under an inverted light microscope at 400x magnification. Samples from 2000 to May 2003, June 2003 to August 2008, and September 2008 onwards were examined with an Olympus CK2, an Olympus IX71, and a Leica DMI 3000, respectively. This latter microscope was equipped with a SPOT Insight digital camera 2 Mpx (Diagnostics Instruments, Sterling Heights, MI). Abundance is expressed for each taxa in number of cells per liter Reference citation to method - Guilloux L., Rigaut-Jalabert F., Jouenne F., Ristori S., Viprey M., Not F., Vaulot, D & Simon, N. 2013. An annotated checklist of Marine Phytoplankton taxa at the SOMLIT : Astan time series off Roscoff (Western Channel, France) : data collected from 2000 to 2010. Cah.Biol.Mar. 54. -Edler L. & Elbrächter M. 2010. The Utermöhl method for quantitative phytoplankton analysis. In: Karlson B, C Cusack & E Bresnan (eds). Microscopic and molecular methods for quantitative phytoplankton analysis, pp. 13-20. UNESCO Publishing, Paris. - NF EN 15204 (2006-12-01). Qualité de l’eau – Norme guide pour le dénombrement du phytoplancton par microscopie inversée (méthode Utermöhl). AFNOR. 39p. - Sournia A. 1978. Phytoplankton manual. Monographs on Oceanographic Methodology, 6: 337.
- Microphytoplankton - Species semi-quantitative occurrences For qualitative analyses, net samples were collected using a simple 20 μm nylon mesh cone (24 cm opening diameter, 80 cm long) towed during 3 minutes in subsurface. A fraction of the net sample was preserved with formalin acidified with acetic acid (formalin (40%HCHO): glacial acetic acid; 1:1, v/v). For net samples, taxa lists were established after examination of a few drops of live or fixed samples Under light microscopes. Three different microscopes were used: an Olympus BH2 (samples from 2000 to July 2001), an Olympus BX51 (samples from August 2001 onwards) equipped with a SPOT RT-slider digital camera (Diagnostics Instruments, Sterling Heights, MI) and an inverted microscope Leica DMI 3000. All taxa are listed and occurrence is expressed according to : 1- present / 2- numerous / 3- dominant Reference to citation method - Guilloux L., Rigaut-Jalabert F., Jouenne F., Ristori S., Viprey M., Not F., Vaulot, D & Simon, N. 2013. An annotated checklist of Marine Phytoplankton taxa at the SOMLIT : Astan time series off Roscoff (Western Channel, France) : data collected from 2000 to 2010. Cah.Biol.Mar. 54. - Sournia A. 1978. Phytoplankton manual. Monographs on Oceanographic Methodology, 6: 337.
- Pico-, nano-phytoplankton, hetero- and autotrophic bacteria - Fonctionnal Groups abundances Seawater samples are collected at -1m and -60m at SOMLIT-Astan Station using a 5 liters Niskin bottle. From 2000 to june 2015, samples are fixed back to the lab. 1485µl subsamples are fixed in cryotubes containing 15µl of Glutaraldehyde 25% (0.25% final concentration). After 15 minutes of fixation at room temperature, tubes are flash frozen in liquid nitrogen and stored at -80°C until FCM analysis. From july 2015, samples are fixed onboard. Cryotubes containing 15µl of a mix of Glutaraldehyde 25% (0.25% final concentration) and Poloxamer 10% (0.01% final concentration) are prepared in the lab and transported in a labtop cooler. The cooler keeps the Glutaraldehyde drops frozen in cryotubes, avoiding manipulator’s exposition when opening. Immediately after subsampling directly from the Niskin bottle (silicone tube, flask), cryotubes are filled with 1485µl seawater. Fixation time at ambient temperature and dark is respected (minimum 15 minutes, and then tubes are stored in the labtop cooler for gentle frozen (-20°C). Back to the lab, samples are stored in a -80°C freezer until analysis. Abundances are expressed in number of cells per milliliter for each functionnal group. Fluorescence intensity are associated to the counts : red autofluorescence for chlorophyll, orange for phycoerythrine and green for heterotroph cells tagged with Sybr Green. Reference to citation method - Troussellier M, Courties C, Zettelmaier S. 1995. Flow cytometric analysis of coastal lagoon bacterioplankton and picophytoplankton: Fixation and storage effects. Est Coast Shelf Sci 40:621-633. - Marie D., Brussaard C., Partensky F. and Vaulot D. Flow cytometric analysis of phytoplankton, bacteria and viruses. 1999. In: Current Protocols in Cytometry. John Wiley & Sons, Inc. 11.11.1-11.11.15. - Marie, D., Rigaut-Jalabert, F. and Vaulot, D. (2014), An improved protocol for flow cytometry analysis of phytoplankton cultures and natural samples. Cytometry, 85: 962–968. doi: 10.1002/cyto.a.22517.
Bibliographic Citations
- Guilloux L., Rigaut-Jalabert F., Jouenne F., Ristori S., Viprey M., Not F., Vaulot, D & Simon, N. 2013. An annotated checklist of Marine Phytoplankton taxa at the SOMLIT : Astan time series off Roscoff (Western Channel, France) : data collected from 2000 to 2010. Cah.Biol.Mar. 54.
Additional Metadata
The dataset only includes occurrences for which an APHIA ID was referenced in the original dataset in the RESOMAR PELAGOS database (http://abims.sb-roscoff.fr/pelagos).