Obras de Urbanização e os Impactos Ambientais sobre a Macrofauna Bentônica: Estudo de Caso em uma Praia do Litoral Cearense

Abstract

ABSTRACT: Coastal areas constantly suffer from degradation processes and environmental losses due to the constant irregular presence of the intertidal zones. These regions have a diverse and adapted biota that contribute significantly to the increase in animal biomass. Accordingly, the objective of this study was to monitor the benthic macrofauna of the intertidal strip of Praia de Arpoeiras, Acaraú - CE, in Brazil, during urbanization works (Aug 2017 to Sep 2018). Thirty samples were collected monthly, totaling 420 samples for macrofauna analysis. For the analysis of textural class and organic matter content, three samples were collected per month. The topographic profile of the beach and abiotic data were also evaluated. A total of 3050 organisms were identified, distributed in the Classes Bivalvia, Gastropoda and Scaphopoda. Arpoeiras Beach showed fluctuations in the topographic profile during the period studied. Significant differences were observed in richness, abundance, diversity indices and composition of the benthic macrofauna throughout the sampling period. The ecological indices showed that at the beginning of the works (Aug to Oct 2017), the diversity was high when compared to the following months. The analyses also showed that the richness and abundance of the macrofauna were not strongly correlated with the abiotic factors studied, organic matter content and textural class, leading to the conclusion that the works were the main factor that interfered with the distribution of the macrofauna. The data presented in this study may serve as input for the elaboration of mitigating measures for the conservation of biodiversity and the maintenance of coastal areas.   Keywords: Bioindicator. Diversity. Malacofauna. Topographic profile.