Dinamismo, complejidad y especificidad de los litorales estuarinos: análisis de la dinámica litoral en Punta Atalaya, Buenos Aires, Argentina

Abstract

Littorals are complex and dynamic spaces, as a result of the interaction between natural dynamics and social assessments over time. This interaction triggers multiple processes, which lend specificity to their coasts. Intertidal environments called marshes are developed in estuarine littorals, which have been intensely modified in large urban metropolises. These environments dynamics have been extensively studied in the northern hemisphere, but scarce research has been performed in the southern hemisphere. In the present work a multitemporal study of a recent developed marsh is done in the coast of Punta Atalaya (district of Magdalena, Buenos Aires, Argentina), located along the intermediate sector of the Argentine coast of the Río de la Plata estuary, using the coastline as an indicator, considering it as the outer limit of this environment. The study was based on its identification in aerial photographs and high-resolution satellite images during the 1929-2016 period. Using specialized software for the multi-temporal change analysis, field work and general and specific bibliography review, an explanatory approximation of the littoral dynamics of this territory was performed. It was determined that the coast of Punta Atalaya presents an accretional tendency during the last century, although changes in the temporal and spatial micro scale are detected throughout the period, responding to accretional and erosive dynamics that derive from the interaction of biological, sedimentary, meteorological and social processes. Each process can trigger multiple responses and have differential impacts in time and space. In this sense, the concepts of balance used in the classic coastal sedimentary balance investigations are questioned.The study area does not have a protected area category, so its environmental assessment in this sense must consider dynamical processes.