Ancient harbour basins, lagoons and coastal lake sediments buried beneath the Mediterranean delta plains can be considered as long-term archives of anthropogenic impacts. The benefits of a micropalaeontological approach in studying archaeological sites located in marginal marine environments are that the archaeologically biased picture can be strongly enriched by detailed palaeolandscapes information.

In marginal marine environments, ostracods are known to be excellent indicators because: (1) many species have a well-known tolerance to salinity variations; (2) the analysis of population structure provides good indications about the autochthony of the assemblage; and (3) they react to even subtle environmental changes, both natural and anthropogenically forced, in terms of densities, distribution of selected species and phenotypic traits.

Examples of ostracod studies will focus on three site typologies: buried landlocked harbours, fluvial harbours and coastal lagoons/lakes. In those studies, the use of different but complementary approaches (archaeology v. micropalaeontology) allowed the reconstruction of diachronic landscapes, linking the natural evolution of coastal and alluvial plains to regional population and settlement dynamics.