Gijon sampling BioMarKs

Transcription

1 Gijon sampling BioMarKs 14 September 2010 Centro Oceanográfico de Gijón-Xixón, Instituto Español de Oceanografía Institut de Ciències del Mar, CSIC, Barcelona, Catalonia, Spain Research Vessel B/O José Rioja Instituto Español de Oceanografía, Laboratorio de Santander Captain: Francisco Javier Cabieces Sampling team ICM, Barcelona: Irene Forn, Massimo Pernice, and Ramon Massana Centro Oceanográfico de Gijón/Xixón: Fernando Piñón, Laura Díaz-Pérez, Iñaki Huskin Thanks to people in Gijón/Xixón Mikel Latasa, Xelu Morán and Rafael Quirós (hosting scientists) Ignacio Reguera (CTD processing) Javier Cristobo (Director)

2 Sampling station GPS position: ' N; ' W Located in front de city of Gijón-Xixón, 12 km offshore, with 110 m bottom This is the second station (S-2) of the "Radial de Xixón", a monitoring station done monthly since 2001 Some recent references from this site: Calvo-Díaz, A. and X.A.G. Morán Seasonal dynamics of picoplankton in shelf waters of the southern Bay of Biscay. Aquat. Microb. Ecol. 42: Calvo-Díaz, A., X.A.G. Morán and L.A. Suárez Seasonality of picophytoplankton chlorophyll a and biomass in the central Cantabrian Sea, southern Bay of Biscay. J. Mar. Syst. 72: Morán, X.A.G Annual cycle of picophytoplankton photosynthesis and growth rates in a temperate coastal ecosystem: a major contribution to carbon fluxes. Aquat. Microb. Ecol. 49: Morán, X.A.G., A. Calvo-Díaz and H.W. Ducklow Total and phytoplankton mediated bottom-up control of bacterioplankton change with temperature in NE Atlantic shelf waters. Aquat. Microbiol. Ecol. 58:

3 1. Realized schedule plan Monday 13 September Load the car at the ICM (Barcelona) with all equipment and drive to Xixón (915 km; 10 hours trip) Tuesday 14 September Arriving Centro Oceanográfico de Xixón. Irene starts to prepare the labs Leave Centro Oceanográfico de Xixón (Massimo, Ramon) Leave Xixón harbor with B/O José Rioja Sample station S-2 - CTD vertical profile: Temperature, salinity, fluorescence and oxygen - Sample at depth 30 m closing all bottles of the rosette (12 x 2L) - Deploy a second CTD for more water at 30 m - Sample at surface by deploying Van Dorn bottles (2x15L). Four times Plankton tow at surface. The net broke before arriving to the ship Arriving to the Xixón harbor Start filtrations and fixations in the lab End all filtrations and fixations Labeling samples Working: GJ_task_fraction_replicate; Final (back at the ICM): GJ.1 to GJ.106 Wednesday 15 September Cleaning bottles and filtration ramps. Pack all material Drive back to Barcelona 2. Meteorological weather Xixón has had a very good summer this year (the best that many people remembers), and the weather for the sampling week was supposed to be rather good. However, the forecast for Tuesday 14 were not totally optimistic, since NE wind was supposed to start at the middle of the day. Finally, the day of sampling was very nice, with blue sky (see picture) and warm temperatures, but also quite windy. However, the rough sea and the ship movement did not prevent a successful sampling.

4 3. Physico-chemical characterization of the water column CTD profiles: Fluorescence, Temperature, Salinity, and Oxygen The water column showed a marked thermal stratification, with temperatures of 20.2 C at the surface, a sharp thermocline from 20 C (20 m) to 14 C (40m), and a bottom water column around 12 C. Salinity was rather constant around There was a sharp fluorescence peak around m, with chlorophyll a values up to 7 µg L -1. Slightly above the fluorescence peak there was an oxygen peak that increased water column background values of 5 ml L -1 to 6 ml L -1. The oxygen peak is likely caused by primary production at the DCM. It must be noted that oxygen and fluorescence measures may not be perfectly calibrated on the CTD. 4. Sampling at sea and properties of the actual depth sampled Surface seawater was sampled with Van Dorn bottles at a depth around 1 m. Actual values from this depth were obtained from the CTD cast (first 2 meters). Samples collected at sea were: 1 bottle (10 L) of whole seawater 1 bottle (50 L) of seawater prefiltered by 2000 µm 2 bottles (50 L + 30 L) of seawater prefiltered by 20 µm

5 DCM was sampled by closing all bottles of the rosette (12 bottles of ~2 L). DCM depth was chosen after inspecting the downcast CTD profile: 30 meters. In reality, the actual depth of closing the bottles was 27 m. This was clearly above the real DCM, as the fluorescence values indicate. Samples collected at sea were: 1 bottle (5 L) of whole seawater 1 bottle (50 L) prefiltered by 20 µm Here are the actual characteristics of the seawater sampled Surface DCM Temperature ( C) Salinity ( ) Fluorescence (µg L -1 ) Oxygen (ml L -1 ) Samples collected Samples collected are kept labeled from GJ.1 to GJ.106. The complete list of samples can be found in the excel file (Samples_GJ_BioMarKs.xls). Here we provide an overview of the samples collected Molecular Plankton samples (24 samples in total) - Metagenomics. Only surface. 25 L were filtered on 142 mm PC filters using the IP pump. Duplicates from the fractions µm, 20-3 µm, µm, µm. Some tubes included 2 filters ( and 3-0.2). 8 samples. - PCR genomics. Surface and DCM. 5 L were filtered on 47 mm PC filters using the LS pump. Four replicates of the fractions 20-3 µm and µm. All tubes included 2 filters. 16 samples. Chemistry (12 samples in total) - Nutrients: Surface and DCM. Two replicates of 100 ml total seawater (4 samples) - Pigments. Surface and DCM. Different volumes were filtered onto GF/F filters: 1L <20 µm; 2L < 3µm. Two replicates (8 samples) Flow cytometry (6 samples in total) - Surface and DCM. Whole seawater. Triplicates (6 samples) Microscopy (24 samples in total) - Inverted Microscopy. Surface and DCM using whole seawater. Quantitative fixation with 4 fixatives: lugol, formol, lugol-glutaraldehyde and acidic lugol (for ciliates). 500 ml and 1L for ciliates. Duplicates in surface and 1 bottle at the DCM (12 samples) - Epifluorescence Microscopy. Surface and DCM. Seawater prefiltered through 2000 µm and filtered onto 0.2 (5 ml), 0.6 (20 ml) and 2 µm (80 ml) black PC filters. Duplicates (12 samples)

6 Filters for FISH (40 samples in total) - FISH picoeukaryotes. Surface and DCM. 100 ml of formaldehyde fixed seawater representing the fraction µm. 10 replicates (20 samples) - FISH nanoplankton. Surface and DCM. 200 ml of formaldehyde fixed seawater representing the fraction 3-20 µm. 5 replicates (10 samples) - FISH prokaryotes. Surface and DCM. 5 ml of formaldehyde fixed seawater representing the fraction µm. 5 replicates (10 samples) 6. Preliminary results of microscopy No inspection has been done with inverted microscopy; electron microscopy samples were not collected. A report of observed taxa was not possible during the sampling week. Epifluorescence counts for the 2 depths have been already done. Samples were clean (typical of offshore waters) and relatively rich in from the picoplankton and nanoplankton organisms. Following are the numbers for bacteria, picocyanobacteria, phototrophic flagellates (in size classes), diatoms and Cryptophytes and heterotrophic flagellates (in size classes). Numbers are in cells ml -1. Bacterial numbers are rather high for a marine sample. Synechococcus numbers are typical of this region at this time, with higher numbers at DCM Phototrophic flagellates are rather abundant and similar at both depths. They are dominated by 3 µm cells (a few true picoeukaryotes of 2 µm). There were a few diatoms (should be counted by inverted microscopy) and a few cryptophytes Heterotrophic flagellates are also rather abundant for a marine sample. Forms of 2 and 3 µm co-dominate.

7 Here is a composite of a few epifluorescence pictures of several protists in the Gijon samples. Starting from upper-left picture, there is a large phototrophic dinoflagellate, two large heterotrophic flagellates (between 5 and 10 µm), a typical heterotrophic nanoflagellate (3 µm), a phototrophic flagellate with 2 chloroplasts (haptophyte-like) and a very small heterotrophic flagellate (2 µm). Other conspicuous forms observed by epifluorescence include choanoflagellates (that account for 5% of HF cells at surface in the size class 2-5 µm), dinoflagellates (that account for 30-40% of HF cells at both depths in the size class >5 µm), Mallomonas (a Synurophyte) and some ciliates.

8 Finally, we point out the observation of a strange organism that was very abundant at the surface sample (and not seen at DCM). Its abundance was 5610 cells ml -1, and it was 2-3 µm in diameter. It was round and regularly covered by bright small dots. Many times it appeared as a single cell, but sometimes formed chains. Some pictures of this wear picoeukaryote are given next (it could belong to the parmales?) 7. Closing remarks Naming of samples Samples have been named consecutively, from GJ.1 to GJ.106. There is an excel file with all the details: "Samples_GJ_BioMarKs.xls" Samples destiny - Roscoff Molecular samples (DNA, RNA) Flow cytometry Pigments for HPLC - Oslo Inorganic nutrients - Barcelona (we will keep) Standard FISH Epifluorescence preparations Microscopy bottles (pending to be know where to go)