Análise dos impactos sociais, ambientais e econômicos da carcinicultura no Brasil: um estudo da influência da atividade na qualidade dos recursos hídricos da região lagunar de Guaraíras, Rio Grande do Norte

Abstract

Anthropogenic influence as a factor of environmental degradation has been widely proven. Shrimp farming is a profitable activity that drives economic and regional development and can be implemented on different scales. However, there is a gap in the scientific literature regarding studies that investigate the pollution potential of shrimp farming in micro and small-scale operations, particularly in the context of the state of Rio Grande do Norte. Thus, this dissertation is composed of two chapters. The first chapter aims to identify and characterize the current knowledge about the economic, social, and environmental impacts of shrimp farming in Brazil. To achieve this, a bibliometric survey was conducted on the Scielo, Scopus, and Web of Science platforms, with the search criterion being works from the years (1993 to 2023) related to the proposed theme. A total of 56 articles related to this topic were analyzed, and the results indicated that the most frequent impacts were on mangrove vegetation, the presence of infectious myonecrosis virus (IMNV), white spot syndrome virus (WSSV), changes in water quality (nutrients and physical and chemical characteristics), wastewater (effluents), environmental changes, and invasive species, among others. This review found that the minimization of the analyzed impacts can be achieved through efficient management strategies aligned with the Sustainable Development Goals (SDGs) proposed by the United Nations (UN) and with the use of technology. In the second chapter, the research aimed to characterize the physical, chemical, microbiological, and phytoplankton quality patterns of the intake water used for pond supply and the effluent generated by micro and small-scale shrimp farming. The results showed that the water quality of shrimp farming in the Guaraíras Lagoon presented parameters within the classification of CONAMA Resolution No. 357/2005 and CONAMA Resolution No. 430/2011. However, after the shrimp production process, changes in physical and chemical parameters were identified, such as dissolved oxygen, pH, suspended solids, and settleable solids (p<0.05), but still within the considered reference values. Phytoplankton levels were related to both changes in physical and chemical parameters and the state's drought season, describing an increase in cyanobacteria, which may be related to nutrient levels available during this period. The predominant phytoplankton classes observed in this study were Bacillariophyceae (44%), followed by Mediophyceae (25%) and Cyanophyceae (17%). The composition of phytoplankton in the intake water showed a statistically significant difference during the dry season, with an average value higher than that observed during the rainy season (p < 0.001). Additionally, considering the species potentially producing cyanotoxins, they presented a concentration five times higher in the effluent compared to the intake water (p < 0.001). From a Brazilian environmental perspective, the results comply with current national legislation, showing that micro and small-scale shrimp farming had a low environmental impact. However, these findings also highlight the need for future studies aimed at monitoring cyanotoxins to deepen the understanding of potential environmental and health impacts of shrimp farming in the region.