GEOHERITAGE: the significance of geosites in Pedro II, Piauí, Brazil

Abstract

The growing appreciation of geoscientific heritage has driven sustainable territorial development strategies, especially under the guidelines of Global Geoparks of the United Nations Educational, Scientific and Cultural Organization. In the state of Piauí, although geodiversity is recognized as rich, regional scientific production on the subject is still limited, as only a few studies on geodiversity, among those developed in Brazil, have been defended in the state. In this context, this study aimed to diagnose and inventory the geosites located in the urban area and immediate surroundings of Pedro II–PI, in addition to investigating the main environmental problems and the relevance of the geosites to the region's socioeconomics, contributing to the conservation of local geoscientific heritage. The research was based on bibliographic surveys, fieldwork, and the application of the systematic inventory proposed by Brilha (2005, 2016). The results allowed the characterization of four geosites: Muro da Entrada, associated with magmatism of the Central Atlantic Magmatic Province; Pirapora, marked by the occurrence of springs and Devonian trace fossils of the species Cosmorhaphe lobata; Mirante da Santa, characterized by columnar jointing; and Garimpo do Boi Morto, related to the hydrothermal genesis of opals. It was concluded, therefore, that although the geosites present high scientific, cultural, and socioeconomic value, anthropic pressure associated with inadequate waste disposal, domestic effluent discharge, and mineral exploration without mitigation compromises environmental integrity and local water resources. This scenario is aggravated by the limited institutional capacity of government agencies for inspection, resulting from the emptying of federal and state agencies since the 1990s, and by the absence of municipal revitalization projects. The urgent need for integrated geoconservation actions, territorial planning, and the strengthening of public policies to consolidate sustainable development in Pedro II is evident.