Detailed Geomorphological Mapping in Coastal Areas: The case of Whale Coast Region (Bahia - Brazil)
ISBN 978-85-88783-11-9
Authors
1Souza, S.; 2Mato Góes, L.; 3Célia de Oliveira, R.
1UNICAMP Email: siriussouza@ige.unicamp.br
2UNICAMP Email: lilianemg@ige.unicamp.br
3UNICAMP Email: reginacoliveira@ige.unicamp.br
Abstract
The planning and management of natural resources nowadays are a necessity to avoid compromising of natural resources and the potentialization or unleashing of morphogenetic processes. In coastal environments the situation becomes alarming, given the fact that these environments have a geology and geomorphology whose nature and evolution favors the intense performance of complex and dynamic processes (Alves; Silva;Sources, 2011). For this planning is possible it is necessary a survey of the physical-natural substrate of the area being managed. Considering that the relief is a component of this substrate, organized forms, which provide sustenance for spatial arrangements of human production (Ross, 2006), a survey and analysis of the characteristics of the relief has relevance to the planning and management environment. In this context, the mapping of the features of relief is an important feature because it allows identifying the spatial framework in which these features are structured and evolve. Griffits and Abraham (2008) state that the geomorphological maps are particularly important for studies planning and environmental planning, as they allow to understand the spatial distribution of past and current processes that are responsible for today's relief forms. Thus, with the study area, the Whale Coast Region (Dominguez 2008) located on the southern part of the state of Bahia - Brazil between latitudes 17 ° 28'52.23 "S and 18 ° 20'4.26" S and meridians 39 ° 11'41.93 "and 40 ° 29'27.03" W of Greenwich, with a total approximate area of 6893.78 square kilometers, the general objective of this work was from the methodological proposal of Tricart (1965) conduct a geomorphological mapping on a detail scale, from the realization of digital stereoscopic aerial photographs on a scale 1: 25,000, and discuss the application of Detailed Geomorpholog-ical Mapping in coastal areas in order to contribute to making the implicit planning and environmental planning of this area. The results of this study indicate the prevalence (84.37%) of Coastal Tablelands Relief characterized by flat interfluves carved with steep walls and flat bottom, supported by the sediments of Barrier Formation. Secondarily, we identified areas of accumulation (15,42%), segmented into plains ( river plain, marine plain and fluvial marineplains) and terraces (river terraces, lacustrine fluvial terraces and marine terraces). Both the plains as the terraces are initiated from the break in the slope imposed by the coastal table-lands, have low slope gradient and consist of topographically flat and downs terrains , interspersed by nume-rous river channels or curved sharply tidal channels , which demonstrates the effective protection of these estuaries to wave action. Finally the realization of complex geomorphological dynamics of the Whale Coast Region - Bahia evidenced by the presence of numerous features and areas of recent deposition should contribute and / or justify the conservation and maintenance of important Brazilian coastal environments associated with the study area such as the Abrolhos Marine National Park, the Extractive Reserve Cassurubá, the Timbebas Reef, the Red Crown Reef, the Viçosa Reef (Andrade, 1994; Leão, 1999; Dominguez, 2008; Dias, 2010; Souza, 2013).