2026-11-112026-11-112026-02-26GOMES, Dênis José Cardoso. Serviços ecossistêmicos na bacia hidrográfica do Rio Caeté: dinâmica hidroclimática, oferta e valorização sob cenários de mudança de uso do solo. Orientadora: Beltrão, Norma Ely Santos. 2026. 199 f. Tese (Doutorado em Ciências Ambientais) - Centro de Ciências Naturais e Tecnologia, Universidade do Estado do Pará, Belém, 2026.https://portaldaposgraduacao.uepa.br/handle/riuepa/448AbertoMudança climáticaDesmatamentoImpacto AmbientalProteção AmbientalClimate changeDeforestationEnvironmental impactEnvironmental protection.TeseCiências Agrárias::Recursos Florestais e Engenharia Florestal::Conservação da NaturezaCiências Agrárias::Recursos Florestais e Engenharia Florestal::Conservação da Natureza::Recuperação de Áreas DegradadasCiências AgráriasEnvironmental changes, driven primarily by natural and anthropogenic factors—namely, climatic extremes and the progression of deforestation—disrupt the functional patterns of environmental systems, including Ecosystem Services (ES). Analyzing alterations in ES within this context of intense environmental change at the watershed level provides insight into the extent to which ES linked to the hydrological cycle—such as water provision and various regulatory functions (climate, gas, hydrological, extreme event mitigation, and erosion control)—are being affected. The objective of this research was to analyze the impact of environmental changes on the provision of ES within the Caeté River Watershed (CRW). The climatic analysis utilized hydroclimatic data (climatic indices, precipitation, maximum air temperature, evapotranspiration, and streamflow). The Mann-Kendall and Pettitt tests were applied to detect signs of climate change and identify the specific year of onset. To assess ES, geospatial data—including altitude, slope, geomorphology, hydrography, road networks, and land use and land cover (LULC)—were acquired to project deforestation and ES in the CRW for the year 2040. Environmental modeling using the Dinamica EGO software was employed for these projections, while the classification of ES was based on the framework established by The Economics of Ecosystems and Biodiversity (TEEB), applied to LULC data from 1985, 2023, and 2040. The valuation of ecosystem services (ESV) was estimated using the benefit transfer method. Statistical calculations were performed in RStudio, and mapping was produced using QGIS 3.3 software. The North Tropical Atlantic sector shows the strongest relationship with the rainfall regime of the Caeté River Basin (BHC). Among the hydrometeorological variables, there is a strong correlation between precipitation and maximum air temperature, as well as between precipitation and the discharge of the Caeté River. No statistically significant trends were identified for the hydrometeorological variables; however, change points in the patterns of climate indices were detected in 1996 (for the North Tropical Atlantic) and 2014 (for the South Tropical Atlantic). The highest volumes of precipitation (2,618.5 mm) and evapotranspiration (1,628.8 mm) are concentrated in the southwestern region of the BHC, while the highest maximum air temperatures occur in the northeastern region. The BHC has experienced extensive deforestation, driven primarily by the expansion of pastureland, which covered approximately 48.3% of the basin by 2023. Oil palm plantations have expanded near the headwaters of the Caeté River—a highly sensitive zone—with alarming negative impacts on local hydrology. Urbanization has also advanced in the lower reaches of the Caeté River, contributing, to a lesser extent, to the loss of riparian vegetation. All these anthropogenic activities have resulted in significant deficits in the ESV of the BHC, amounting to losses of approximately 2 billion dollars; livestock farming, in particular, has diminished regulating ecosystem services (such as the regulation of gases, climate, water, extreme events, and erosion control). Agriculture threatens the ecosystem services (ES) related to water provision and regulation (including hydrological regulation, mitigation of extreme events, and erosion control). Projections for the year 2040 are entirely pessimistic. There have been no signs of significant hydroclimatic shifts. Deforestation has been the primary driver of the decline in ecosystem services within the BHC (Hydrographic Basin); consequently, containment measures—such as the implementation of agroforestry systems—are urgently needed as short-term responses.