Resumen de The Holocene Paleoenvironmental reconstruction of the Ria Formosa Lagoon system (SW Iberia Peninsula): foraminifera based study
Laura Pereira, Ana Gomes, T. Boski, Carlos Sousa Mendes, Dorota Szalaj, Simon Connor
The fossil foraminifera assemblages of the Ria Formosa Lagoon has been studied in two sediment cores collected in the system. Four distinct assemblages were identified along the analyzed cores, each one of them characteristic of a different Foraminiferal Indicator of Marine Influence (FIMI). The variation of FIMI indicates the presence marine environment between ca. 9500- 3000 cal. yr. B.P. as a result of the postglacial sea-level rise. From 3000 cal. yr. B.P. until present, occurred an ecological shift to a most confined salt-marsh environment, probably as a result of progressive enclosing of the lagoons behind the barrier islands and silting of this semi enclosed body. The referred shift is inferred mainly from the increase in the abundance of the salt-marsh species Jadammina macrescens and Trochammina inflata and the decrease of the low intertidal species Ammonia tepida and Haynesina germanica that provoked an alteration in the FIMI.
