The South Indian Ocean - Biogeochemical studies on water masses, nutrient and stable isotope distribution, and particulate matter in an oligotrophic ocean region
,
Der Süd-Indische Ozean - Biogeochemische Studien zu Wassermassen, Nährstoff- und Isotopenverteilung und partikulärem Material in einer oligotrophen Meeresregion
Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky
Erscheinungsjahr:
2020
Medientyp:
Text
Schlagworte:
Indian Ocean subtropical gyre
Nutrients and stable isotopes
Water masses
Sinking particles and particulate organic matter
Sediment trap moorings
Surface sediments
550: Geowissenschaften
38.00: Geowissenschaften: Allgemeines
ddc:550:
Beschreibung:
This thesis presents biogeochemical element cycling processes in the less explored oligotrophic subtropical gyre of the South Indian Ocean. A detailed water mass analysis was conducted by using physical water column profiles that were basis to understand the complex distribution of nutrients and stable isotope signals in order to identify the sources and transformation processes in the nitrogen cycle. Furthermore, a five-year sediment trap experiment (2015-2019) was carried out in order to assess the particulate organic carbon (POC) export below the euphotic zone, further into the ocean interior, and its final accumulation in the deep-sea sediments. This constitutes to the organic carbon pump and is a central part of the global carbon cycle. Thus, these investigations contribute to the baseline knowledge on nitrogen and carbon cycle processes and its budgets in oligotrophic areas that are most likely expand under global warming and thus getting even more important on a global scale during the next decades.