IOW Logo

EVAR:
The Benguela Upwelling System under climate change - Effects of variability in physical forcing on carbon and oxygen budgets

Duration:
01.01.2019 - 31.12.2022
Project manager:
Prof. Dr. Heide Schulz-Vogt
Funding:
BMBF - Bundesministerium für Bildung und Forschung
Researchfocus:
Focus 2: Basin-scale ecosystem dynamics
Partners:
GEOMAR - Helmholtz Zentrum für Ozeanforschung Kiel
Marum - Zentrum für Marine Umweltwissenschaften der Universität Bremen

Time series recording physical forcing in high resolution have shown that the Benguela Upwelling System (BUS) is characterized by a pronounced variability in upwelling intensity resulting in equally high variations in oxygen supply and primary production. Even though some earlier studies addressed microbially driven processes either in the water column or in the sediments of the BUS, the effect of these fluctuations on the overall activity and rates of microorganisms has not yet been studied. Furthermore, frequent occurrence of exceptionally high sulfide concentrations in sediments, occasional accumulation of sulfide in bottom waters, and sporadic eruptions of sulfide all show that the system is far from being at steady state. As both oxygen supply and the occurrence of sulfide are critical parameters, which directly affect all forms of life, these fluctuations will have an important impact on the overall budget of carbon and consequences for the emission of greenhouse gases. In areas of extremely high primary production the feed back from the sediment, including the activity of macrobenthic organisms and bacterial phosphorus cycling, has to be considered in order to estimate the overall budgets via regional ecosystem models. Together with our regional partners we aim to address the effect of variations in upwelling intensity on environmental conditions and budgets through a comprehensive, multidisciplinary approach.

Publikationen

  • Hoffman, L. and M. L. Zettler (2024). Neoleptonidae (Bivalvia) from Namibia. Iberus 42: 165-173
  • Hoffman, L. and M. L. Zettler (2024). Galeommatoidea (Bivalvia) from Namibia (Part 2). Iberus 42: 155-164
  • Bick, A. and M. L. Zettler (2024). Description of three new species of Amphitritides Augener, 1922 (Terebellida, Annelida) from the coast of Namibia (South West Africa). Zootaxa 5446: 42-64, doi: 10.11646/zootaxa.5446.1.2
  • Brandt, P., M. H. Bordbar, P. Coelho, R. A. I. Koungue, M. Körner, T. Lamont, J. F. Lübbecke, V. Mohrholz, A. Prigent, M. Roch, M. Schmidt, A. K. van der Plas and J. Veitch (2024). Physical drivers of southwest African coastal upwelling and its response to climate variability and change. In: Sustainability of Southern African Ecosystems under Global Change: Science for Management and Policy Interventions. Ed. by G. P. von Maltitz, G. F. Midgley, J. Veitch, C. Brümmer, R. P. Rötter, F. A. Viehberg and M. Veste. Cham: Springer International Publishing: 221-257, 978-3-031-10948-5, doi: 10.1007/978-3-031-10948-5_9
  • Zettler, M. L., R. Bastrop and J. K. Lowry (2023). Ten thousand kilometres away and still the same species? The mystery of identity of Scopelocheirus sp. (Amphipoda: Scopelocheiridae) from the South Atlantic. Rec. Aust. Mus. 75: 609-622, doi: 10.3853/j.2201-4349.75.2023.1896
  • Bordbar, M. H., V. Mohrholz and M. Schmidt (2023). Low confidence in multi-decadal trends of wind-driven upwelling across the Benguela Upwelling System. Earth Syst. Dynam. 14: 1065-1080, doi: 10.5194/esd-14-1065-2023
  • Kossack, M., F. Scholz, C. H. Anderson, P. Vosteen, C.-C. Su, V. Mohrholz and M. Zabel (2023). Sedimentary molybdenum and uranium cycling under seasonally contrasting redox conditions on the Namibian Shelf. Geochim. Cosmochim. Acta 358: 174-191, doi: 10.1016/j.gca.2023.08.014
  • Amorim, K. and M. L. Zettler (2023). Gradients and instability: Macrozoobenthic communities in the Benguela Upwelling System off Namibia. Estuar. Coast. Shelf Sci. 291: 108421, doi: 10.1016/j.ecss.2023.108421
  • Zettler, M. L. and L. Hoffmann (2023). Condylocardiidae (Bivalvia) from Namibia. Basteria 87: 2-10
  • Zettler, M. L. and L. Hoffmann (2022). Nucula (Nuculidae, Bivalvia) from upper bathyal depths off Namibia. Iberus 40: 291-299
  • Amorim, K., N. Loick-Wilde, B. Yuen, J. T. Osvatic, J. Wäge-Recchioni, B. Hausmann, J. M. Petersen, J. Fabian, D. Wodarg and M. L. Zettler (2022). Chemoautotrophy, symbiosis and sedimented diatoms support high biomass of benthic molluscs in the Namibian shelf. Sci. Rep. 12: 9731, doi: 10.1038/s41598-022-13571-w
  • Zettler, M. L. and L. Hoffmann (2021). Nuculana cornidei Altimira, 1974 (Bivalvia: Nuculanidae) from Namibia. Miscellanea Malacologica 9: 5-9
  • Zettler, M. L. and L. Hoffmann (2021). A wide distribution of Waisiuconcha haeckeli (Bivalvia: Vesicomyidae) in the eastern Atlantic Ocean. Miscellanea Malacologica 9: 1-3
  • Zettler, M. L. and A. Alf (2021). A new Polititapes Chiamenti, 1900 (Bivalvia: Veneridae) from Namibia. Arch. Molluskenkd. 150: 1-4, doi: 10.1127/arch.moll/150/001-004
  • Zettler, M. L. and L. Hoffmann (2021). New species in Galeommatoidea (Bivalvia) from Namibia ; Nuevas especies de Galeommatoidea (Bivalvia) de Namibia. Iberus 39: 195-208, doi: 10.5281/zenodo.5039262
  • Zettler, M. L. (2021). An example for transatlantic hitchhiking by macrozoobenthic organisms with a research vessel. Helgoland Mar. Res. 75, 1: 4, doi: 10.1186/s10152-021-00549-w
  • Arévalo-Martínez, D. L., T. Steinhoff, P. Brandt, A. Körtzinger, T. Lamont, G. Rehder and H. W. Bange (2019). N2O Emissions from the northern Benguela Upwelling System. Geophys. Res. Lett. 46: 3317-3326, doi: 10.1029/2018gl081648