Centros urbanos, ciclo hidrológico e a pesca artesanal na área de influência da Hidrelétrica de Belo Monte, Rio Xingu, Amazônia Oriental

Abstract

Artisanal fisheries in the Amazon constitute a socioecological system that is fundamental to food security, economic subsistence, and the cultural identity of riverine populations. However, this system has been profoundly reconfigured by increasing anthropogenic pressures, particularly urban expansion and hydrological regulation associated with large hydropower projects. We investigated how these two processes act in transforming artisanal fisheries along the Xingu River, in eastern Amazonia, under the influence of the Belo Monte Hydroelectric Power Plant. Urban influence was quantified through a Human Intensity Index that combines distance to urban centers and population size, while hydrological effects were assessed based on variation in annual discharge under a regulated regime. Fishing data were obtained from landing records collected in localities along the Xingu River, totaling 78,964 sampled landings between 2012 and 2022. The analyses integrated mixed models and multivariate approaches to examine responses in catch per unit effort, diversity, species composition, and fishing methods.The results indicate that increasing human intensity is associated with changes in fishing strategies, including greater use of motorized boats, reduced species diversity, and declining productivity in more selective fishing methods. Catch composition becomes progressively homogenized in areas under stronger urban influence. The effects of discharge on fisheries are selective and non-linear, being concentrated on catch per unit effort and species composition. The results indicate that the discharge values currently practiced under the operational regime of the Belo Monte Hydroelectric Power Plant are insufficient to continuously sustain fisheries productivity in the Xingu River, as positive responses only emerge at more adequate and persistently maintained levels of discharge, whereas isolated or short-duration hydrological events do not produce consistent ecological effects. Urbanization and hydrological regulation are leading to a reorganization of fisheries in the Xingu River, intensifying the ecological and socioeconomic vulnerability of riverine communities.