Salinization of marshes in Argentina: natural vs. anthropogenic factors.

CAROL, ELEONORA; ALVAREZ MARÍA DEL PILAR; IDASZKIN, YANINA LORENA; SANTUCHI, LUCIA

Integrating Ecosystems in Coastal Engineering Practice. Water Perspectives in Emerging Countries.

Cuvillier Verlag

Año: 2017; p. 138 - 149

In the littoral zone of Argentina, marsh environments under arid, semi-arid and humid conditions are numerous. In this work, salt marshes located in Río de la Plata Estuary, Bahía Blanca Estuary, San Antonio Bay, and San Jorge Gulf were studied aiming at understanding the processes that determine the occurrence of evaporates in salt marshes, and analyzing the importance of naturaland anthropogenic factors. QuickBird and Google Earth images were used to identify the geomorphologic, anthropogenic and hydrological characteristics, and selected samples were examined under a binocular magnifying glass, through X-ray diffraction (XRD) and scanning electron microscopy (SEM). The four studied marshes are located along a latitudinal gradient on the Argentina Atlantic coast, where the climatic conditions are wet in the northern sector and arid in the marshes of the southern sector. The tidal conditions change from north to south as microtidal in Ajó marsh, meso-tidal in Bahía Blanca, and macro-tidal in San Antonio and Fracasso marshes. In each area, contrasting climatic conditions, tidal and anthropogenic influence and hydrological characterization were studied both the anthropogenic and the natural factors condition the soils marshes salinization. Although it is expected that a greater amount of salts occur in arid marshes soils, it was observed that salt development in altered marshes with humidclimates are more important. This shows the high negative influence that an anthropogenic modification can have over sensitive ecosystems as the marshes.