Caracterização do ambiente praial de Pirangi do Norte (Parnamirim-RN), com ênfase na análise granulométrica do sedimento

Abstract

The coastal zone is one of the most complex environments in nature, with high hydrodynamic. Tourist beaches are heavily used for recreation and users are increasingly demanding regarding the quality of resources and the available infrastructure. Pirangi do Norte beach (Parnamirim - RN), is located near to Pirangi river (23km far from Natal). The study aimed to characterize the Pirangi beach with emphasis on particle size analysis of the sediment. Sampling took place from November 2015 to April 2016. A total of 120 sediment samples were collected at 10 sites perpendicular to the coast, and classified according to the particle size range of Wentworth (1922). Measuring of the beach it was held in the same locations in two periods of tide (2.7 and -0.1). It was also carried out the beach characterization in 10 stretches of approximately 200m each, where twelve parameters were assessed. Each of parameters was assessed based on an attribute scale ranging from the worst (1) to the best (3) quality. The results showed that the sediment grain size distribution from Pirangi beach ranged mainly from fine to medium sand. The beach has an average width of over 100m at low tide, and has no evidence of coastal erosion. Regarding the evaluated parameters, the best conditions occur in the extreme south and north. The main problems observed on the beach are the lack of vegetation, pollution from solid waste and sewage and high commercial activity in some places, especially in the central stretches of beach. This work may be useful for the environmental planning of the Pirangi beach.