Articles | Volume 4, issue 1
Earth Syst. Sci. Data, 4, 149–165, 2012

Special issue: MAREDAT – Towards a world atlas of marine plankton functional...

Earth Syst. Sci. Data, 4, 149–165, 2012

  22 Nov 2012

22 Nov 2012

A global diatom database – abundance, biovolume and biomass in the world ocean

K. Leblanc1, J. Arístegui2, L. Armand3, P. Assmy4, B. Beker5, A. Bode6, E. Breton7,8,9, V. Cornet1, J. Gibson10, M.-P. Gosselin11, E. Kopczynska12, H. Marshall13, J. Peloquin14, S. Piontkovski15, A. J. Poulton16, B. Quéguiner1, R. Schiebel17, R. Shipe18, J. Stefels19, M. A. van Leeuwe19, M. Varela6, C. Widdicombe20, and M. Yallop21 K. Leblanc et al.
  • 1Aix-Marseille Université, Université du Sud Toulon-Var, CNRS/INSU, IRD, MIO, UM 110, 13288, Marseille, Cedex 09, France
  • 2Instituto de Oceanografía y Cambio Global, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas, Spain
  • 3Department of Biological Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
  • 4Norwegian Polar Institute, Fram Centre, Hjalmar Johansens gt. 14, 9296 Tromsø, Norway
  • 5Laboratoire des Sciences de l'Environnement Marin, UMR6539, CNRS, Institut Universitaire Européen de la Mer (IUEM), Place Nicolas Copernic, Technopôle Brest Iroise, 29280 Plouzané, France
  • 6Instituto Español de Oceanografía, Centro Oceanográfico de A Coruña Apdo. 130, 15080, A Coruña, Spain
  • 7Univ Lille Nord de France, 59000 Lille, France
  • 8ULCO, LOG, 62930 Wimereux, France
  • 9CNRS, UMR8187 LOG, 62930 Wimereux, France
  • 10Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tasmania 7001, Australia
  • 11The Freshwater Biological Association, The Ferry Landing, Far Sawrey, Ambleside, LA22 0LP, UK
  • 12Institute of Biochemistry and Biophysics, Department of Antarctic Biology, Polish Academy of Sciences, 02-141 Warszawa, Poland
  • 13Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
  • 14Inst. f. Biogeochemie u. Schadstoffdynamik, Universitätstrasse 16, 8092 Zürich, Switzerland
  • 15Department of Marine Sciences, Sultan Qaboos University, Sultanate of Oman
  • 16National Oceanography Centre, Waterfront Campus, Southampton, SO14 3ZH, UK
  • 17Laboratoire des Bio-Indicateurs Actuels et Fossiles (BIAF), UPRES EA 2644, Université d'Angers, 49045 Angers CEDEX 01, France
  • 18UCLA, Los Angeles, California 90095, USA
  • 19University of Groningen, Centre for Life Sciences Ecophysiology of Plants, P.O. Box 11103, 9700 CC Groningen, The Netherlands
  • 20Plymouth Marine Laboratory, Prospect Place, West Hoe, Plymouth, PL1 3DH, UK
  • 21School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK

Abstract. Phytoplankton identification and abundance data are now commonly feeding plankton distribution databases worldwide. This study is a first attempt to compile the largest possible body of data available from different databases as well as from individual published or unpublished datasets regarding diatom distribution in the world ocean. The data obtained originate from time series studies as well as spatial studies. This effort is supported by the Marine Ecosystem Model Inter-Comparison Project (MAREMIP), which aims at building consistent datasets for the main plankton functional types (PFTs) in order to help validate biogeochemical ocean models by using carbon (C) biomass derived from abundance data. In this study we collected over 293 000 individual geo-referenced data points with diatom abundances from bottle and net sampling. Sampling site distribution was not homogeneous, with 58% of data in the Atlantic, 20% in the Arctic, 12% in the Pacific, 8% in the Indian and 1% in the Southern Ocean. A total of 136 different genera and 607 different species were identified after spell checking and name correction. Only a small fraction of these data were also documented for biovolumes and an even smaller fraction was converted to C biomass. As it is virtually impossible to reconstruct everyone's method for biovolume calculation, which is usually not indicated in the datasets, we decided to undertake the effort to document, for every distinct species, the minimum and maximum cell dimensions, and to convert all the available abundance data into biovolumes and C biomass using a single standardized method. Statistical correction of the database was also adopted to exclude potential outliers and suspicious data points. The final database contains 90 648 data points with converted C biomass. Diatom C biomass calculated from cell sizes spans over eight orders of magnitude. The mean diatom biomass for individual locations, dates and depths is 141.19 μg C l−1, while the median value is 11.16 μg C l−1. Regarding biomass distribution, 19% of data are in the range 0–1 μg C l−1, 29% in the range 1–10 μg C l−1, 31% in the range 10–100 μg C l−1, 18% in the range 100–1000 μg C l−1, and only 3% > 1000 μg C l−1. Interestingly, less than 50 species contributed to > 90% of global biomass, among which centric species were dominant. Thus, placing significant efforts on cell size measurements, process studies and C quota calculations of these species should considerably improve biomass estimates in the upcoming years. A first-order estimate of the diatom biomass for the global ocean ranges from 444 to 582 Tg C, which converts to 3 to 4 Tmol Si and to an average Si biomass turnover rate of 0.15 to 0.19 d−1. Link to the dataset: doi:10.1594/PANGAEA.777384.