Analysis of the Water Balance of the Mata Engenho Uchôa Wildlife Refuge Reserve - Metropolitana Sul

Abstract

The Southern Metropolitan Basin - 33, located in the Metropolitan Region of Recife, with 30.94 km², represents an important hydrological and ecological system, although it is under intense pressure due to accelerated urban growth. This context reflects problems such as environmental degradation, pollution of water bodies and increased social vulnerability. The basin has important ecosystems, such as mangrove and restinga areas, which are crucial for biodiversity and climate regulation. However, disorderly occupation and changes in land use have led to the significant loss of these habitats and increased the risks of floods and landslides, especially in vulnerable communities. The study focused on the 33 sub-basin, located in part of the Atlantic Forest of Pernambuco, and analyzed daily time series data between 1963 and 2023, provided by the SWAT (Soil Water Assessment Tool) model. Variables such as precipitation, soil water content, evapotranspiration (actual and potential) and groundwater discharge were evaluated. The results showed that approximately 47% of precipitation is lost through evapotranspiration, while 13.5% is percolated and 32% corresponds to surface flow. The average annual precipitation is 2,180 mm, with seasonal variations that significantly affect the region's water patterns. The historical periods analyzed indicate a reduction in extreme precipitation events since the 2000s, possibly related to climate change and sustainable management of the basins. Phenomena such as El Niño and La Niña play determining roles in water variability, while urbanization intensifies surface runoff and reduces infiltration, altering the hydrological cycle. Evapotranspiration also reflects the interaction between climate, vegetation and water availability, with annual patterns that highlight the impacts of climate events and changes in land use. The objective of this research was to analyze the hydrological dynamics of sub-basin 33 and identify the impacts of climate change and urbanization on the hydrological cycle, focusing on the water balance and the challenges of sustainable water resource management. The results highlight the need for integrated public policies that balance environmental conservation and urban development, promoting water security and quality of life for local communities.