The Mar Menor, a coastal lagoon located in the southeast of Spain, is one of the largest lagoons on the Mediterranean coastline. This singular area is subject to a wide range of uses, including large tourist resorts and intensive agriculture. The importance of the lagoon and its salt marshes in terms of biodiversity has been recognised in numerous international protection programmes. The distinctive environment of the lagoon has long been attractive for visitors. A surge in tourist activities has taken place in the area since the early 1960s, characterised by intense urban development along the lagoon’s perimeter to accommodate the growing seasonal population. This phenomenon has particularly affected La Manga, a sandy bar that is 20 km in length. La Manga acts as a barrier between the lagoon and the Mediterranean Sea, crossed by five more or less functional channels called ‘golas’. The urbanization process has changed the water flow system between the inside and seawater through the channels. The changes have affected coastal dynamics, the longitudinal profile of the coast and the lagoon’s ecosystem. The coastal lagoon is also highly threatened by other pollution variables derived from agricultural lands. The water derived from the Tajo-Segura transfer generated a profound land transformation of the adjacent agricultural areas, which changed from extensive dry crop farming to intensively irrigated crops, disturbing the lagoon dramatically. This paper analyses both land transformations around the coastal perimeter of the Mar Menor during the last 50 years and shows the environmental impact with its consequences on the ecosystem. Although numerous biological studies have been carried out in the Mar Menor, a better understanding of the consequences of land transformation in the perimeter of the lagoon is still necessary to understand the lagoon’s situation. The results of territorial management in the Mar Menor lagoon need to be addressed in order to develop successful strategies in the area to protect this valuable ecosystem and its services.
land transformation, coastal developmentalism, Mar Menor lagoon, La Manga, environmental impact, agriculture pollution
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