Christian Depraetere is a research fellow at the Institut de Recherche pour le Développement (IRD) and worked for several decades in Africa, the Indian Ocean, the Caribbean and the Mediterranean. Its research topics focus on one side with the impact of Climate change (CC) on water resources and on the other side, on geohistorical processes within insular regions.

In the wake of Joël Bonnemaison's "îléité" and Grant McCall's nissology, he proposes a regional and global approach of dispersion, diffusion and migration phenomena within island and archipelagic contexts, thus defining "nomothetic" nissology. Within the general scope of Island Studies, the aim is to contribute to a generic geohistorical approaches of various insular and archipelagic patterns throughout the world. The systematic use of comparative methods seeks to highlight similarities rather than singularities at various scales of time and space to decipher the entanglement between the evolution human societies and environmental dynamics in specific fragmented patterns like islands and archipelagoes.

At global scale, he contributed to the implementation of the Global Island Database (Base de données Insulaires Mondiale BIM) for the purpose of defining a reference data set available for all scientists working on various issues related to islands. On the methodological aspect, his contribution deals with geostatistical analysis of island spaces and definition of "islandscapes" (landscape+seascape). Following Godfrey Baldacchino's envision of "A world of islands", he suggested the concept of "The world archipelago" considering all the emerged lands as a functional entity during the successive stages of globalization. More recently, his researches are more related to specific thematic (Neolithic archaeology, historical thalassocraties, CC and tourism) in the islands of the Mediterranean and Baltic seas.