The Coastal Lagoon Ciénaga Grande de Santa Marta, Colombia

Abstract

Located on the central Caribbean coast of Colombia, the lagoon complex of Ciénaga Grande de Santa Marta (CGSM) is part of the eastern delta of the Magdalena River, Colombia’s largest river. The delta and the CGSM rest on a coastal plain, which was formed by marine and fluvial sedimentary depositions during Holocene transgression and regression phases (10,000 b.p.), while the surrounding formations date back to the Cenozoic era. The lagoon complex (1,321 km²) comprises the Ciénaga Grande (450 km²), the Ciénaga de Pajarales (120 km²), several smaller lagoons, creeks, and channels (150 km²), and mangrove swamps. A narrow, continuous sandbar (Isla de Salamanca) borders the entire CGSM complex to the north. At the eastern end of Isla de Salamanca a 120-m-wide and 10-m-deep inlet (Boca de la Barra) connects the shallow (average depth 1.2 m) Ciénaga Grande lagoon to the Caribbean Sea (Fig. 2.1). The CGSM is a highly productive ecosystem but has suffered severe degradation in the last four decades. However, the system is likely to considerably recuperate if current restoration plans are successful.