Everyone is aware of the special relationship that man has with the coast; from the beginning of man- kind, humans have been attracted to the littoral zone for the construction of settlements and the use of its resources. Subsequently, humans have evolved, leaving an increasingly large footprint on this medium. Hence, there is a need to deepen our knowledge to protect against the threat that we ourselves pose. Coastal regression mainly due to the lack of sediment is a global problem. The environmental, economic and social interest makes the study of coastal regression a major problem in the institutions. This article places the study area in Denia (Alicante, Spain). In this population, for some time, there has been concern about the effect on the beaches of the sharp erosion of the coastline. The Marineta Cassiana beach has been chosen for this study because of its special location and the set of elements of the environment. Thus, with respect to the beach study, it is observed that the land beside it is a fully urbanized area, which has suffered due to the pressure of development in this area since 1956, limited as it is by background mountains. Therefore, this study encompasses different aspects of the regression of the coast. To this end, a study of the historical evolution of the beach since 1956 has been carried out. The hydrological modelling of river basins discharging to the beach and their changes due to the alteration of the landscape has been carried out, using dynamics and morphological characterization of the area and an analysis of the erosion of these basins. Also, the historical evolution of the surf on the beach, as well as changes in the morphology of the coast, which have influenced the marine climate, have been taken into account.
GIS, Posidonia oceanica, shoreline, urban development
 Misra, A. & Balaji, R., Decadal changes in the land use/land cover and shoreline along the coastal districts of southern Gujarat, India. Environmental Monitoring and Assessment, 187(7), p. 461, 2015. http://dx.doi.org/10.1007/s10661-015-4684-2
 Nicholls, R.J. & Small, C., Improved estimates of coastal population and exposure to hazards released. Eos, Transactions American Geophysical Union, 83(28), pp. 301– 305, 2002. http://dx.doi.org/10.1029/2002EO000216
 Nguyen, H.H., McAlpine, C., Pullar, D., Leisz, S.J. & Galina, G., Drivers of coastal shoreline change: case study of Hon Dat coast, Kien Giang, Vietnam. Environmental Management, 55(5), pp. 1093–1108, 2015. http://dx.doi.org/10.1007/s00267-015-0455-7
 Clark, J., Coastal Zone Management Handbook, CRC Press/Lewis Publishers: Boca Raton, Florida, USA, p. 720, 1996.
 Defeo, O., McLachlan, A., Schoeman, D.S., Schlacher, T.A., Dugan, J. & Jones, A., Threats to sandy beach ecosystems: a review. Estuarine, Coastal and Shelf Science, 81, pp. 1–12, 2009. http://dx.doi.org/10.1016/j.ecss.2008.09.022
 Schlacher, T.A., Dugan, J., Schoeman, D.S., Lastra, M., Jones, A., Scapini, F., McLachlan, A. & Defeo, M., Sandy beaches at the brink. Diversity and Distributions, 13, pp. 556–560, 2007. http://dx.doi.org/10.1111/j.1472-4642.2007.00363.x
 Aragonés, L., Pagán, J.I., López, M.P. & García-Barba, J., The impacts of Segura River (Spain) channelization on the coastal seabed. Science of the Total Environment, 543, pp. 493–504, 2016. http://dx.doi.org/10.1016/j.scitotenv.2015.11.058
 Aragonés, L., García-Barba, J., García-Bleda, E., López, I. & Serra, J.C., Beach nourishment impact on Posidonia oceanica: case study of poniente beach (Benidorm, Spain). Ocean Engineering, 107, pp. 1–12, 2015. http://dx.doi.org/10.1016/j.oceaneng.2015.07.005
 IGME. Instituto Geológico y Minero Español, available at http://info.igme.es/visorweb/
 Morote, Á.F. & Hernández, M., Urban sprawl and its effects on water demand: a case study of Alicante, Spain. Land Use Policy, 50, pp. 352–362, 2016. http://dx.doi.org/10.1016/j.landusepol.2015.06.032
 Salvadore, E., Bronders, J. & Batelaan, O., Hydrological modelling of urbanized catchments: a review and future directions. Journal of Hydrology, 529, pp. 62–81, 2015. http://dx.doi.org/10.1016/j.jhydrol.2015.06.028