Vulnerabilidade e conservação do patrimônio edificado em Natividade e Porto Nacional

Abstract

This study analyzed the vulnerability of the built heritage in the historic centers of Natividade and Porto Nacional, in the state of Tocantins, based on the interaction among climate change, the material characteristics of traditional construction systems, changes in craft-based knowledge, and public response capacity. The objective was to examine how material and construction characteristics, exposure to climatic and environmental agents, and the weakening of traditional knowledge affect the conservation of the heritage sites under study. The research was applied in nature, exploratory, descriptive, and analytical in character, interdisciplinary in approach, and combined qualitative and quantitative methods. The procedures included bibliographic and documentary review, analysis of heritage designation processes, technical visits, direct observation, photographic records, characterization of construction systems, and physical and mechanical tests on adobe blocks and ceramic roof tiles. The social dimension was investigated through semi-structured interviews with residents, master builders and craftspeople, as well as qualified professionals, guided by Oral History and interpreted through Content Analysis. CMIP6 climate projections were also examined for maximum temperature, precipitation, wind speed, and radiation under the SSP1-2.6, SSP3-7.0, and SSP5-8.5 scenarios. The results showed that the adobe samples were predominantly sandy, had low plasticity, and displayed heterogeneous mechanical behavior. The ceramic roof tiles showed low geometric uniformity and variations in water absorption, impermeability, and flexural strength. The interviews demonstrated that heritage supports memory, identity, belonging, everyday use, and income generation. However, its conservation is hindered by maintenance costs, conflicts between regulatory protection and property owners’ autonomy, insufficient technical and financial assistance, and the weakening of intergenerational transmission of traditional knowledge. The qualitative assessment identified, in both municipalities, very high priority for risks related to water and inadequate drainage, physical and structural instability, incompatible interventions, and fire. Roof failures, biodeterioration, and harmful human actions received higher priority in Porto Nacional, while environmental stress remained high in both municipalities. Vulnerability results from the interaction among climate, materiality, use, maintenance, construction knowledge, and response capacity, requiring preventive conservation, climate adaptation, technical assistance, local training, and stronger public policies.