Estudo da paisagem acústica submarina na região do Arraial do Cabo, Rio de Janeiro, Brasil

Abstract

The underwater soundscape is seen as an element of the ecosystem. The fundamental principle of soundscape ecology lies on the fact that sound is a part of nature and provides valuable information on the environment in which it is produced. The sounds gener ated by the species living in a particular habitat create a specific environment, a local soundscape. However, the noise created by human activities is considered an environmental pollutant with the potential of affecting marine ecosystems. In this study, acoustic measurements were taken with the goal of profiling the local soundscape and identifying patterns of biological and anthropogenic sounds in the region of Arraial do Cabo, Rio de Janeiro, Brazil. Results show the existence of a pattern for sounds of biological origin. This pattern shows influence from tide conditions and periods of sunlight. The biophonic pattern maintained some characteristics. For instance, levels of mean power peak at dusk and dawn as well as their decrease during daytime, it did not have significant temporal variations. Besides, sounds of anthropogenic origin interfered greatly in this soundscape pattern. The interferences happened during late - night hours and daytime. These timeframes are related to fishing activities at the dock and to the presence of tourism boats, typical in this region. Therefore, the acoustic measurements taken (power, entropy , and maximum frequency) have proven effective in helping to quantify the acoustic impact on the natural soundscape. These results enabl ed a holistic vision of the biological behavior and of the impacts caused by human activities on the environment.