Resumen:
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Doñana Natural Park is a good global example of the sedimentary filling of a broad tidal estuary during the Mid-Late Holocene, after the last postglacial sea-level rise. The timing of this rise is not well defined yet in the Gulf of Cádiz, since the oldest evidence of coastal sedimentation, located at the right bank of the mouth of the old Guadalquivir Estuary, dates ack to ca. 5,000 ears ago. The first evolutionary stages of the embayment indicate an obvious marine influence, dominated by waves and storms from the SW. Since ca. 4,000 years ago, protection provided by the growing coastal spit barrier of Doñana favored the development of a sheltered marsh dominated by tides and fluvial currents. About 2,200 years ago, since the time Romans controlled the area, the estuary was dominated by marshlands with a wide lagoon at its mouth (Lacus Ligustinus), and the current landscape of Doñana started to form. The evolution of the last 2,000 years includes the quick and continuous growth of coastal barriers by longshore drift, the origin of the present-day marshland landscape and the development of dune fields migrating inland towards the wetlands.
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