Monitoramento e modelagem de processos hidrológicos como base para a gestão de recursos hídricos em região semiárida

Abstract

The water budget is essential in several areas of knowledge, such as agriculture, forestry and hydrology. Within the activities in rural environments, some practices are directly related to the water budget, such as irrigation management, human supply and animal welfare, among others. The understanding of the hydrological cycle assists the water resources planning and management, in environmental studies and hydraulic projects, in watersheds. At the current scenario, the challenges of environmental management in the face of the impacts of climate change have increased the need for technological advances and the results of scientific research more accessible and ready for use. Proper monitoring, analysis and management of natural resources (especially water) require the implementation of a joint multidisciplinary approach to create rational and applied policies for better management scenarios. The objective of the research was to investigate the hydrological dynamics of soil moisture, vegetation, climatological balance and climatic indexes in the sub-basin of the Ingazeira Dam, located in the semi-arid region of Pernambuco, calibrate the hydrological model and analyze the water balance and watershed of the Ipanema River with the SWAT model. Differences were found between the moisture content and the vegetation cover and a marked decrease in rainfall totals recorded in the basin from 2011 to 2017. Moreover, increasing temperatures and aridity index trends, resulting in a decrease in humidity and increased evapotranspiration have been observed in the basin area, presenting water deficiency for the region. Thus, it is verified that hydrological monitoring and surveying provided an order of magnitude of soil moisture and its correlations with hydro-climatic data, contributing to better management of water resources in the Ipanema-PE river basin. In spite of high limitations of experimental measurements in the Ipanema basin, the SWAT model presented an acceptable adjustment for monthly data, evidenced by a NASH of 0.85 and an R2 of 0.88 in the calibration. Although the values found for NASH and R2 are considered acceptable, it is expected that with the continuity of the field measurements, an improvement of the such management tool will be obtained and available.