The Universität Hamburg is part of the environmental studies in the INDEX (Indian Ocean Exploration) program, which was established by the BGR (Federal Institute for Geosciences and Natural Resources), Hanover. The INDEX license area is located in the oligotrophic subtropical gyre of the South Indian Ocean. Sinking particulate matter samples were collected by sediment trap mooring 04-04 to measure vertical particle flux quantitatively and qualitatively. Mooring 04-04 was deployed with three sediment traps at different depths during cruise PE446 (RV Pelagia) and recovered during cruise SO271 (RV Sonne).