Beach nourishment impact on Posidonia oceanica: Case study of Poniente Beach (Benidorm, Spain)

• Potential environmental impacts of beach nourishment on Posidonia oceanica meadow.
• Study of the historical evolution of Poniente Beach descriptive variables (1956–2012).
• Relation between Posidonia oceanica burial and beach regression.
• Suggestion of beach nourishment system to reduce costs and environmental impacts.
• Prediction of Poniente Beach future situation.

The importance of nourishment processes on the beaches of Mediterranean Sea has been increasing since the end of the 20th century due to its socio-economical awareness (tourismboost) and environmental implications (possible impact on Posidonia oceanica meadows and important processes of dredging and earth movements). However, in many cases, and especially in eastern Spain, relevant actions have been made which had caused that, after 20 years, the beaches in which these works were carried out will be in a similar situation with the original one.The present study analyzed the Poniente Beach (Benidorm, Spain), a beach where the nourishment works of 1991 have caused the disappearance of the Posidonia oceanica meadows and a regression process that will lead to the disappearance of the beach in a few years.To this end, data from bathymetry, georeferenced orthophotos, grain size analysis and swell study have been obtained and analyzed, understanding the importance of the works done to be consistent with the environment in which they were developed, and providing a work process which can ensure the existence of the nourished beach starting from the maintenance of Posidonia oceanica meadows.