Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 5 3 2008 10.5194/bg-5-669-2008 http://www.biogeosciences.net/5/669/2008/ http://www.biogeosciences.net/5/669/2008/bg-5-669-2008.html http://www.biogeosciences.net/5/669/2008/bg-5-669-2008.pdf 669 678 2008-05-06 Availability of phosphate for phytoplankton and bacteria and of glucose for bacteria at different pCO2 levels in a mesocosm study T. Tanaka T. F. Thingstad T. Løvdal H.-P. Grossart A. Larsen M. Allgaier M. Meyerhöfer K. G. Schulz J. Wohlers E. Zöllner U. Riebesell Marine Microbiology Research Group (MMRG), Department of Biology, University of Bergen, Bergen, Norway Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB-Neuglobsow), Department of Limnology of Stratified Lakes, Alte Fischerhuette 2, D-16775 Stechlin, Germany Leibniz Institute of Marine Sciences (IFM-GEOMAR), Düsternbrooker Weg 20, 24105 Kiel, Germany present address: Faculty of Science and Technology, Department of Mathematics and Natural Sciences, University of Stavanger, N-4036 Stavanger, Norway Availability of phosphate for phytoplankton and bacteria and of glucose for bacteria at different pCO2 levels were studied in a mesocosm experiment (PeECE III). Using nutrient-depleted SW Norwegian fjord waters, three different levels of pCO2 (350 μatm: 1×CO2; 700 μatm: 2×CO2; 1050 μatm: 3×CO2) were set up, and nitrate and phosphate were added at the start of the experiment in order to induce a phytoplankton bloom. Despite similar responses of total particulate P concentration and phosphate turnover time at the three different pCO2 levels, the size distribution of particulate P and 33PO4 uptake suggested that phosphate transferred to the >10 μm fraction was greater in the 3×CO2 mesocosm during the first 6–10 days when phosphate concentration was high. During the period of phosphate depletion (after Day 12), specific phosphate affinity and specific alkaline phosphatase activity (APA) suggested a P-deficiency (i.e. suboptimal phosphate supply) rather than a P-limitation for the phytoplankton and bacterial community at the three different pCO2 levels. Specific phosphate affinity and specific APA tended to be higher in the 3×CO2 than in the 2×CO2 and 1×CO2 mesocosms during the phosphate depletion period, although no statistical differences were found. Glucose turnover time was correlated significantly and negatively with bacterial abundance and production but not with the bulk DOC concentration. This suggests that even though constituting a small fraction of the bulk DOC, glucose was an important component of labile DOC for bacteria. Specific glucose affinity of bacteria behaved similarly at the three different pCO2 levels with measured specific glucose affinities being consistently much lower than the theoretical maximum predicted from the diffusion-limited model. This suggests that bacterial growth was not severely limited by the glucose availability. Hence, it seems that the lower availability of inorganic nutrients after the phytoplankton bloom reduced the bacterial capacity to consume labile DOC in the upper mixed layer of the stratified mesocosms. Allgaier, M., Riebesell, U., and Grossart, H.-P.: Microbial response to enrichment in $p$CO2 and subsequent changes in phytoplankton and nutrient dynamics, Biogeosciences Discuss., 5, 317–359, 2008. Ammerman, J. W., and Azam, F.: Bacterial 5'-nucleotidase in aquatic ecosystems: a novel mechanism of phosphorus regeneration, Science, 227, 1338–1340, 1985. Barlow, R. G., Cummings, D. G., and Gibb, S. W.: Improved resolution of mono- and divinyl chlorophylls a and b and zeaxanthin and lutein in phytoplankton extracts using reverse phase C-8 HPLC, Mar. Ecol. Prog. Ser., 161, 303–307, 1997. Bellerby, R. G. J., Schulz, K. G., Riebesell, U., Neill, C., Nondal, G., Johannessen, T., and Brown, K. R.: Marine ecosystem community carbon and nutrient uptake stoichiometry under varing ocean acidification during the PeECE III experiment, Biogeosciences Discuss., 4, 4631–4652, 2007. Berman, T.: Phosphatase release of inorganic phosphorus in Lake Kinneret, Nature, 224, 1231–1232, 1969. Button, D. K.: The physical base of marine bacterial ecology, Microb. Ecol., 28, 273–285, 1994. Caldeira, K. and Wickett, M. E.: Anthropogenic carbon and ocean pH, Nature, 425, 365, 2003. Cembella, A. D., Anita, N. J., and Harrison, P. J.: The utilization of inorganic and organic phosphorus compounds as nutrients by eucaryotic microalgae: a multidiciplinary perspective: part 1, CRC Crit. Rev. Microbiol., 10, 317–391, 1984. Delille, B., Harlay, J., Zondervan, I., Jacquet, S., Chou, L., Wollast, R., Bellerby, R. G. J., Frankignoulle, M., Borges, A. V., Riebesell, U., and Gattuso, J. P.: Response of primary production and calcification to changes of $p$CO2 during experimental blooms of the coccolithophorid \textitEmiliania huxleyi, Global Biogeochem. Cycles, 19, GB2023, doi:10.1029/2004GB002318, 2005. Egge, J. K., Thingstad, T. F., Engel, A., Bellerby, R. G. J., and Riebesell, U.: Primary production during nutrient-induced blooms at elevated CO2 concentrations, Biogeosciences Discuss., 4, 4385–4410, 2007. Engel, A., Delille, B., Jacquet, S., Riebesell, U., Rochelle-Newall, E., Terbrüggen, A., and Zondervan, I.: Transparent exopolymer particles and dissolved organic carbon production by \textitEmiliania huxleyi exposed to different CO2 concentrations: a mesocosm experiment, Aquat. Microb. Ecol., 34, 93–104, 2004. Engel, A., Zondervan, I., Aerts, K., Beaufort, L., Benthien, A., Chou, L., Delille, B., Gattuso, J.-P., Harlay, J., Heemann, C., Hoffmann, L., Jacquet, S., Nejstgaard, J., Pizay, M.-D., Rochelle-Newall, E., Schneider, U., Terbrueggen, A., and Riebesell, U.: Testing the direct effect of CO2 concentration on a bloom of the coccolithophorid \textitEmiliania huxleyi in mesocosm experiments, Limnol. Oceanogr., 50, 493–507, 2005. Fagerbakke, K. M., Heldal, M., and Norland, S.: Content of carbon, nitrogen, oxygen, sulfur and phosphorus in native aquatic and cultured bacteria, Aquat. Microb. Ecol., 10, 15–27, 1996. Fitzgerald, G. P. and Nelson, T. G.: Extractive and enzymatic analyses for limiting or surplus phosphorus in algae, J. Phycol., 2, 32–37, 1966. Geider, R. J. and La Roche, J.: Redfield revisited: variability of C:N:P in marine microalgae and its biochemical basis, Eur. J. Phycol., 37, 1–17, 2002. Grossart, H.-P., Allgaier, M., Passow, U., and Riebesell, U.: Testing the effect of CO2 concentration on the dynamics of marine heterotrophic bacterioplankton, Limnol. Oceanogr., 51, 1–11, 2006a. Grossart, H. P., Czub, G., and Simon, M.: Algae-bacteria interactions and their effects on aggregation and organic matter flux in the sea, Environ. Microbiol., 8, 1074–1084, 2006b. Hansen, H. P., and Koroleff, F.: Determination of nutrients. in: Methods of seawater analysis, edited by: Grasshoff, K., Kremling, K., and Ehrhardt, M., 3rd edition, Wiley VCH, Weinheim, Germany, 159–228, 1999. Havskum, H., Thingstad, T. F., Scharek, R., Peters, F., Berdalet, E., Sala, M. M., Alcaraz, M., Bangsholt, J. C., Zweifel, U. L., Hagström, Å., Perez, M., and Dolan, J. R.: Silicate and labile DOC interfere in structuring the microbial food web via algal-bacterial competition for mineral nutrients: Results of a mesocosm experiment, Limnol. Oceanogr., 48, 129–140, 2003. Hobbie, J. E. and Crawford, C. C.: Respiration corrections for bacterial uptake of dissolved organic compounds in natural waters, Limnol. Oceanogr., 14, 528–532, 1969. Hoppe, H.-G.: Phosphatase activity in the sea, Hydrobiol., 493, 187–200, 2003. Jansson, M., Olsson, H., and Pettersson, K.: Phosphatases; origin, characteristics and function in lakes, Hydrobiol., 170, 157–175, 1988. Koch, A. L.: The adaptive responses of \textitEscherichia coli to a feast and famine existence, edited by: Rose, A. H. and Wilkinson, J. F., Adv. Microb. Physiol. Vol 6. Academic Press Inc., London, UK, 147–217, 1971. Koroleff, F.: Determination of phosphorus. in: Methods of seawater analysis, edited by: Grasshoff, K., Ehrhardt, M., and Kremling, K., Second, revised and extended edition. Verlag Chemie, Weinheim, Germany, 1983. Larsen, J. B., Larsen, A., Thyrhaug, R., Bratbak, G., and Sandaa, R.-A.: Response of marine viral populations to a nutrient induced phytoplankton bloom at different $p$CO2 levels, Biogeosciences, 5, 523–533, 2008. Lee, S. and Fuhrman, J. A.: Relationships between biovolume and biomass of naturally derived marine bacterioplankton, Appl. Environ. Microbiol., 53, 1298–1303, 1987. Leonardos, N. and Geider, R. J.: Elevated atmospheric carbon dioxide increases organic carbon fixation by \textitEmiliania huxleyi (Haptophyta), under nutrient-limited high-light conditions, J. Phycol., 41, 1196–1203, 2005. Marie, D., Partensky, F., Vaulot, D., and Brussaard, C.: Enumeration of phytoplankton, bacteria, and viruses in marine samples. in, Current Protocols in Cytometry, Vol 11. John Wiley & Sons, Inc., 1–15, 1999. Martínez-Martínez, J., Norland, S., Thingstad, T. F., Schroeder, D. C., Bratbak, G., Wilson, W. H., and Larsen, A.: Variability in microbial population dynamics between similarly perturbed mesocosms, J. Plankton Res., 28, 783–791, 2006. Murphy, J. and Riley, J. P.: A modified single solution method for the determination of phosphate in natural waters, Analytica Chemica Acta, 27, 31–36, 1962. Myklestad, S. and Sakshaug, E.: Alkaline phosphatase activity of \textitSkeletonema costatum populations in the Trondheimsfjord, J. Plankton Res., 5, 557–563, 1983. Paulino, A. I., Egge, J. K., and Larsen, A.: Effects of increased atmospheric CO2 on small and intermediate sized osmotrophs during a nutrient induced phytoplankton bloom, Biogeosciences Discuss., 4, 4173–4195, 2007. Perry, M. J.: Alkaline phosphatase activity in subtropical central north Pacific waters using a sensitive fluorometric method, Mar. Biol., 15, 113–119, 1972. Qian, J., and Mopper, K.: Automated high-performance, high-temperature combustion total organic carbon analyzer, Anal. Chem., 68, 3090–3097, 1996. Redfield, A. C., Ketchum, B. H., and Richards, F. A.: The influence of organisms on the composition of sea water, edited by: Hill, M. N., The sea. Vol. 2. Interscience, New York, USA, 1963. Rhee, G.-Y.: A continuous culture study of phosphate uptake, growth rate and polyphosphate in \textitScenedesmus sp., J. Phycol., 9, 495–506, 1973. Riebesell, U.: Effects of CO2 enrichment on marine phytoplankton, J. Oceanogr., 60, 719–729, 2004. Riebesell, U., Schulz, K. G., Bellerby, R. G. J., Fritsche, P., Meyerhöfer, M., Neill, C., Nondal, G., Oschlies, A., Wohlers, J., and Zöllner, E.: Enhanced biological carbon consumption in a high CO2 ocean, Nature, 450, 545–548, 2007. Rochelle-Newall, E., Delille, B., Frankignoulle, M., Gattuso, J. P., Jacquet, S., Riebesell, U., Terbruggen, A., and Zondervan, I.: Chromophoric dissolved organic matter in experimental mesocosms maintained under different $p$CO2 levels, Mar. Ecol. Prog. Ser., 272, 25–31, 2004. Schulz, K. G., Riebesell, U., Bellerby, R. G. J., Biswas, H., Meyerhöfer, M., Müller, M. N., Egge, J. K., Nejstgaard, J. C., Neill, C., Wohlers, J., and Zöllner, E.: Build-up and decline of organic matter during PeECE III, Biogeosciences Discuss., 4, 4539–4570, 2007. Sciandra, A., Harlay, J., Lefevre, D., Lemee, R., Rimmelin, P., Denis, M., and Gattuso, J. P.: Response of coccolithophorid \textitEmiliania huxleyi to elevated partial pressure of CO2 under nitrogen limitation, Mar. Ecol. Prog. Ser., 261, 111–122, 2003. Simon, M., and Azam, F.: Protein content and protein synthesis rates of planktonic marine bacteria, Mar. Ecol. Prog. Ser., 51, 201–213, 1989. Sinha, V., Williams, J., Meyerhofer, M., Riebesell, U., Paulino, A. I., and Larsen, A.: Air-sea fluxes of methanol, acetone, acetaldehyde, isoprene and DMS from a Norwegian fjord following a phytoplankton bloom in a mesocosm experiment, Atmos. Chem. Phys., 7, 739–755, 2007. Sterner, R. W. and Elser, J. J.: Ecological stoichiometry, Princeton University Press, Princeton, 2002. Tanaka, T., Henriksen, P., Lignell, R., Olli, K., Seppälä, J., Tamminen, T., and Thingstad, T. F.: Specific affinity for phosphate uptake and specific alkaline phosphatase activity as diagnostic tools for detecting P-limited phytoplankton and bacteria, Estuaries and Coasts, 29, 1226–1241, 2006. Thingstad, T. F. and Rassoulzadegan, F.: Conceptual models for the biogeochemical role of the photic zone microbial food web, with particular reference to the Mediterranean Sea, Prog. Oceanogr., 44, 271–286, 1999. Thingstad, T. F., Skjoldal, E. F., and Bohne, R. A.: Phosphorus cycling and algal-bacterial competition in Sandsfjord, western Norway, Mar. Ecol. Prog. Ser., 99, 239–259, 1993. Thingstad, T. F., Øvreås, L., Egge, J. K., Løvdal, T., and Heldal, M.: Use of non-limiting substrates to increase size; a generic strategy to simultaneously optimize uptake and minimize predation in pelagic osmotrophs?, Ecol. Lett., 8, 675–682, 2005. Toggweiler, J. R.: Carbon overconsumption, Nature, 363, 210–211, 1993. Tortell, P. D., DiTullio, G. R., Sigman, D. M., and Morel, F. M. M.: CO2 effects on taxonomic composition and nutrient utilization in an Equatorial Pacific phytoplankton assemblage, Marine Ecology-Progress Series, 236, 37–43, 2002. Wolf-Gladrow, D., Riebesell, U., Burkhardt, S., and Bijma, J.: Direct effect of CO2 concentration on growth and isotopic composition of marine plankton, Tellus, 51B, 461–476, 1999. Zondervan, I., Zeebe, R. E., Rost, B., and Riebesell, U.: Decreasing marine biogenic calcification: A negative feedback on rising atmospheric pCO2, Global Biogeochem. Cycles, 15, 507–516, 2001.