This repository contains raw data from flow cytometry, diagnostic pigments, and macro- and micro-nutrient measurements collected in the Caribbean Sea and the Atlantic Ocean, around Basse-Terre Island. Concentrations of macro- and micro-nutrients and anions are also provided for six rivers sampled from upstream to downstream in southern Basse-Terre. Additionally, data on particulate organic carbon and diagnostic pigments obtained during sediment incubation experiments are included. All data were collected during two field campaigns conducted in Guadeloupe (French West Indies) in June 2023 and January 2024.