Temporal analysis of environmental quality of Ponta Negra beach (Natal-RN) related to coastal erosion: what has changed in 10years?

Abstract

Ponta Negra beach is one of the main tourist destinations in the state of Rio Grande do Norte (Brazil), which is used by many tourists. This study aimed to perform a temporal analysis of the environmental quality of the beach related to coastal erosion, considering environmental and anthropic parameters at two different times, 10years apart. The total length of the beach (3km) was subdivided into 10 sections of approximately 300m numbered 1-10, from south to north. Eight parameters were assessed based on an attribute scale ranging from the worst to the best possible quality (1-4) found in each section. The sum of the parameters was used to determine the final score. To determine the level of environmental quality, four conditions were considered (excellent, good, regular, and bad). Compared with the first sampling period, the results indicated that 50% of the beach showed reduction in environmental quality. The "excellent" condition, obtained in the first sampling period for two of the sections, was not repeated in the second period. Two situations were responsible for the decrease in beach quality over time: the erosive process that took place after 2012 and consequent reduction in vegetation cover and width of the beach environment. The current state of the beach and its gradual loss of quality over the years indicate an unpromising trend towards recovery. The methodology used in this study can be easily repeated in other locations with similar problems, generating data that can help in understanding local conditions.