Title: Coastline morphodynamics and defences in Mazatlán, Mexico
Authors: Temitope D. Timothy Oyedotun; Arturo Ruiz-Luna; Alma Guadalupe Navarro-Hernández
Addresses: Centro de Investigación en Alimentación y Desarrollo, A.C., Av. Sábalo-Cerritos, P.O. Box 711, Mazatlán, 82100, Sinaloa, México; Department of Geography, Faculty of Earth and Environmental Sciences (FEES), University of Guyana, Leslie Cummins Building, Turkeyen Campus, Greater Georgetown, P.O. Box 101110, Guyana ' Centro de Investigación en Alimentación y Desarrollo, A.C., Av. Sábalo-Cerritos, P.O. Box 711, Mazatlán, 82100, Sinaloa, México ' Centro de Investigación en Alimentación y Desarrollo, A.C., Av. Sábalo-Cerritos, P.O. Box 711, Mazatlán, 82100, Sinaloa, México
Abstract: The coastline of Mazatlán City has retreated within the contemporary (2012-2016) timeline. Changes were analysed from Landsat (7 and 8) images of 2012-2016, and GPS field surveys of 2016. The pattern of yearly shoreline retreat showed a northern region of high annual shoreline retreats (>1 m yr−1) and a southern region of very low retreat (<1 m yr−1). Any assumption of overall erosion must be made with caution since there have been periods of accretion along the beach, even when the analysis of shoreline change suggests an overall dominance of erosion; also, the rates of erosion differed among the three analysed sections/sedimentary cells. Such mechanisms are the natural processes by which the coastline adjusts to the changing forces in the coastal zone. However, the coastal defence structures compromise this natural sedimentary system and its associated coastal dynamics through the elimination or reduction of sediment supply. There is a need for interdisciplinary monitoring and management of this coastal zone and of this type of coastal areas in tropical regions of the world, not only for tourism purposes and protection of the properties on the land but also for shoreline preservation.
Keywords: shoreline changes; coastal defences; morphodynamics; coastal processes; Mazatlán; shoreline preservation.
Interdisciplinary Environmental Review, 2018 Vol.19 No.2, pp.168 - 183
Received: 27 Jun 2017
Accepted: 16 Mar 2018
Published online: 24 Jul 2018 *