Characterization and evolution of the sediments of a Mediterranean coastal lagoon located next to a former mining area

Coastal lagoons are ecosystems that are relatively enclosed water bodies under the influence of both the terrestrial and the marine environment, being vulnerable to human impacts. Human activities, such as mining extraction, are significant anthropogenic coastal stressors that can negatively affect ecosystems and communities. In light of the above, the objective of this research is to examine the influence of metal mining activities on the composition of sediments of a Mediterranean coastal lagoon, named Mar Menor. This paper presents a comprehensive characterization for grain size, mineralogy, geochemistry and organic matter of sediments of this coastal lagoon, investigating their variation along space and time. Sedimentation dynamics are ruling clearly the grain size predominant in each area of the Mar Menor coastal lagoon, determining the existence of entrainment, transport and sedimentation areas. For minerals, elements and organic matter, sedimentation dynamics are also determining their distribution. •The influence of a former metal mining area on a coastal lagoon, Mar Menor, was studied.•Grain size, mineralogy, geochemistry and organic matter of sediments were analysed.•Human activities are affecting sedimentation dynamics of the coastal lagoon.•The mining wastes have spread along the lagoon.•Some events have determined the evolution of sediments since XIV century.