CHANGES IN LAND USE AND OCCUPATION AND ALTERATIONS IN THE HYDROLOGICAL REGIME IN A WATERSHED IN SOUTHERN AMAZONIA

Abstract

The importance of studying the relationship between changes in land use and land cover and hydrometeorological dynamics is fundamental for evaluating water management and water availability, and this was the objective of the present study in the Celeste River basin between 2013 and 2023. Using data from MapBiomas and hydrometeorological series, territorial transformations and their effects on streamflow were evaluated through water balance assessments and trend analyses. The results showed that, despite the expansion of agricultural areas and the reduction of pastures and native vegetation, no significant changes in land use were observed. The observed streamflow series (Qm) presented variations throughout the study period, with greater water availability until 2018 and a decline in subsequent years, while the Mann-Kendall test indicated a significant weak negative trend (p = 0.05). The comparison between observed streamflow and streamflow estimated by the water balance (Qcalc = P – ETR) revealed discrepancies, suggesting that processes not captured by the simplified model should be reassessed, such as the analysis of a longer data series or the inclusion of information regarding water resource use. These findings reinforce that the integration of hydrometeorological and land-use information is fundamental for water resources management.