Blar i forfatter "Bernhard, Joan M."

Viser treff 1-3 av 3

    • Ammonium and Sulfate Assimilation Is Widespread in Benthic Foraminifera 

      LeKieffre, Charlotte; Jauffrais, Thierry; Bernhard, Joan M.; Filipsson, Helena L.; Schmidt, Christiane; Roberge, Helene; Maire, Olivier; Panieri, Giuliana; Geslin, Emmanuelle; Meibom, Anders (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-20)
      Nitrogen and sulfur are key elements in the biogeochemical cycles of marine ecosystems to which benthic foraminifera contribute significantly. Yet, cell-specific assimilation of ammonium, nitrate and sulfate by these protists is poorly characterized and understood across their wide range of species-specific trophic strategies. For example, detailed knowledge about ammonium and sulfate assimilation ...

    • Deposit-feeding of Nonionellina labradorica (foraminifera) from an Arctic methane seep site and possible association with a methanotroph 

      Schmidt, Christiane; Geslin, Emmanuelle; Bernhard, Joan M.; LeKieffre, Charlotte; Svenning, Mette Marianne; Roberge, Helene; Schweizer, Magali; Panieri, Giuliana (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-30)
      Several foraminifera are deposit feeders that consume organic detritus (dead particulate organic material with entrained bacteria). However, the role of such foraminifera in the benthic food web remains understudied. Foraminifera feeding on methanotrophic bacteria, which are 13C-depleted, may cause negative cytoplasmic and/or calcitic δ13C values. To test whether the foraminiferal diet includes ...

    • Keystone Arctic paleoceanographic proxy association with putative methanotrophic bacteria 

      Bernhard, Joan M.; Panieri, Giuliana (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-13)
      Foraminifera in sediments exposed to gas-hydrate dissociation are not expected to have cellular adaptations that facilitate inhabitation of chemosynthesis-based ecosystems because, to date, there are no known endemic seep foraminifera. To establish if foraminifera inhabit sediments impacted by gas-hydrate dissociation, we examined the cellular ultrastructure of <i>Melonis barleeanus</i> (Williamson, ...