El registro sedimentario antropoceno de las marismas cantábricasrespuesta al cambio climático en curso

Abstract

The study of natural and regenerated salt marshes can provide key information about the future coastal evolution, particularly under the current climatic scenario of global warming and accelerated sea-level rise. A foraminifera-based transfer function has been developed and applied to a core obtained in a natural salt marsh, which allowed us to reconstruct a relative sea-level rise rate of 2 mm yr-1 during the 20th century. This reconstruction has been dated using the 137Cs and 210Pb sedimentary accumulation rates and has been compared to the Brest tide gauge data, which show a similar trend. On the other hand, the study of a recently regenerated salt marsh has shown high sedimentation rates (14 mm yr-1) during this regeneration process. This rapid regeneration process (less than 10 years) is of great interest for environmental management of coastal zones particularly where extensive reclaimed land exist that could be easily restored as an adaptation measure under the current scenario of accelerating sea-level rise, since these environments accrete sediment very fast until they reach equilibrium with the tidal frame.