First-order estimate of the planktic foraminifer biomass in the modern ocean

Abstract

Abstract. Planktic foraminifera are heterotrophic mesozooplankton of global marine abundance. The position of planktic foraminifers in the marine food web is different compared to other protozoans and ranges above the base of heterotrophic consumers. Being secondary producers with an omnivorous diet, which ranges from algae to small metazoans, planktic foraminifers are not limited to a single food source, and are assumed to occur at a balanced abundance displaying the overall marine biological productivity at a regional scale. With a new non-destructive protocol developed from the bicinchoninic acid (BCA) method and nano-photospectrometry, we have analysed the protein-biomass, along with test size and weight, of 754 individual planktic foraminifers from 21 different species and morphotypes. From additional CHN analysis, it can be assumed that proteinbiomass equals carbon-biomass. Accordingly, the average individual planktic foraminifer protein-and carbonbiomass amounts to 0.845 µg. Samples include symbiont bearing and symbiont-barren species from the sea surface down to 2500 m water depth. Conversion factors between individual biomass and assemblage-biomass are calculated for test sizes between 72 and 845 µm (minimum test diameter). Assemblage-biomass data presented here include 1128 sites and water depth intervals. The regional coverage of data includes the North Atlantic, Arabian Sea, Red Sea, and Caribbean as well as literature data from the eastern and western North Pacific, and covers a wide range of oligotrophic to eutrophic waters over six orders of magnitude of plankticforaminifer assemblage-biomass (PFAB). A first order estimate of the average global planktic foraminifer biomass production (> 125 µm) ranges from 8.2-32.7 Tg C yr −1 (i.e. 0.008-0.033 Gt C yr −1 ), and might be more than three times as high including neanic and juvenile individuals adding up to 25-100 Tg C yr −1 . However, this is a first estimate of regional PFAB extrapolated to the global scale, and future estimates based on larger data sets might considerably deviate from the one presented here. This paper is supported by, and a contribution to the Marine Ecosystem Data project (MAREDAT).

Large Contribution of Pteropods to Shallow CaCO3 Export

“…We compiled data on the CaCO 3 :POC ratio in pteropods as 0.52 ± 0.24 mol/mol ( n = 5 only). The CaCO 3 :POC ratio in coccolithophores was taken as 0.10 ± 0.05 mol/mol ( n = 127, Heinle, ), and in foraminifers as 0.49 ± 0.50 mol/mol ( n = 549, Schiebel & Movellan, ). We could not find data on gross growth efficiency and the fraction of grazing that is egested as DOC and POC for pteropods or foraminifers.…”

MAREDAT: towards a world atlas of MARine Ecosystem DATa

“…There are six papers relating to autotrophic groups: picophytoplankton (Buitenhuis et al, 2012a), diazotrophs (Luo et al, 2012), coccolithophores , Phaeocystis , diatoms (Leblanc et al, 2012), and HPLC-based phytoplankton pigments . There are six papers relating to heterotrophic groups: picoheterotrophs (Bacteria and Archaea, Buitenhuis et al, 2012b), microzooplankton (here, we briefly reiterate and correct the microzooplankton biomass database that was recently published by Buitenhuis et al, 2010), planktic foraminifers (Schiebel and Movellan, 2012), mesozooplankton (Moriarty et al, 2013), pteropods (Bednaršek et al, 2012), and macrozooplankton (Moriarty et al, 2013). By this collaborative effort we are able to provide global databases for 9 out of the 10 PFTs that were proposed by Le Quéré et al (2005).…”

“…In addition to the 9 PFTs mentioned above, we include data on two groups of zooplankton calcifiers, the calcite producing planktic foraminifers (Schiebel and Movellan, 2012) and the pteropods (Bednaršek et al, 2012), which include both shelled aragonite-producing species and naked species. These data should be valuable in complementing research into phytoplankton calcifiers, i.e.…”

MAREDAT: towards a World Ocean Atlas of MARine Ecosystem DATa

“…This MARine Ecosystem biomass DATa (MAREDAT) special issue in Earth System Science Data is the result, with 11 papers on 11 PFTs and 1 paper describing a database of phytoplankton pigments (http://www.earth-syst-sci-data.net/ special issue7.html). There are six papers relating to heterotrophic groups: picoheterotrophs (Bacteria and Archaea, Buitenhuis et al, 2012b), microzooplankton (here, we briefly reiterate and cor- 15 rect the microzooplankton biomass database that was recently published by Buitenhuis et al, 2010), planktic foraminifers (Schiebel and Movellan, 2012), mesozooplankton (Moriarty and O'Brien, 2012), pteropods (Bednaršek et al, 2012), and macrozooplankton (Moriarty et al, 2012). There are six papers relating to heterotrophic groups: picoheterotrophs (Bacteria and Archaea, Buitenhuis et al, 2012b), microzooplankton (here, we briefly reiterate and cor- 15 rect the microzooplankton biomass database that was recently published by Buitenhuis et al, 2010), planktic foraminifers (Schiebel and Movellan, 2012), mesozooplankton (Moriarty and O'Brien, 2012), pteropods (Bednaršek et al, 2012), and macrozooplankton (Moriarty et al, 2012).…”

“…In addition to the 9 PFTs mentioned above, we include data on two groups of zoo- 15 plankton calcifiers, the calcite producing planktic foraminifers (Schiebel and Movellan, 2012) and the pteropods (Bednaršek et al, 2012), which include both shelled aragonite producing species and naked species. These data should be valuable in complementing research into phytoplankton calcifiers, i.e.…”