Chapter

Lagunas costeras y estuarios

In book: La Biodiversidad en Veracruz un estudio de estado, Edition: 1A, Chapter: Lagunas costeras y estuarios, Editors: CONABIO, pp.297-313

ABSTRACT INTRODUCCIÓN El litoral mexicano abarca 11 592.77 km 2 , y se caracteriza por sus variados y ricos ecosistemas cos-teros como: bahías, ensenadas, lagunas costeras y estuarios que, por siglos, han representado un sus-tento importante para los mexicanos. En todo el país, existen entre 125 y 130 lagunas costeras que abarcan un área de 15 000 km 2 . Las lagunas coste-ras, se definen geomorfológicamente como depre-siones en la costa por debajo del promedio máximo de las mareas más altas, siempre protegidas de las fuerzas del mar por algún tipo de barrera que puede ser de tipo físico, principalmente de arena, y con comunicación con el mar de manera permanente o efímera; o barrera tipo hidrodinámica por la presen-cia de agua dulce y agua de mar (Lankford, 1977). Otro rasgo importante en la zona costera es la descarga de los ríos directa al mar a lo que se deno-mina como estuarios. Estos rasgos se definen hidro-dinámicamente como cuerpos de agua costeros, semicerrados con conexión libre al mar y dentro del cual el agua de mar se diluye significativamente con el agua dulce que proviene del drenaje terrestre (Pritchard, 1967). Tanto las lagunas costeras como los estuarios son ecosistemas que destacan por su importancia económica, ya que son áreas de pesca artesanal y medio de vida de miles de pescadores. Además su importancia radica en la función ecoló-gica de su alta productividad primaria que permite a estos ecosistemas ser un lugar de crianza, reproduc-ción y resguardo de muchos organismos acuáticos de valor comercial, permitiendo así, concentrar un gran espectro de la biodiversidad. Las costas enfrentan graves efectos negativos no sólo por las actividades que ahí se desarrollan, sino por su interacción con zonas continentales (figura 1). Destacan las descargas domesticas e industriales, escurrimientos superficiales, arrastre y contamina-ción del suelo, aumento en la implementación de caminos costeros y el consecuente incremento en el tráfico de vehículos, la extracción petrolera, los des-arrollos turísticos y sobre todo su fragilidad ante los impactos de los fenómenos hidrometeorológicos Lagunas costeras y estuarios

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