Alterações no regime de vazão e precipitação em trecho da Bacia do Rio Araçuaí, Minas Gerais: caminhamos para a escassez hídrica?

Abstract

The analysis of historical series of precipitation and flow allows obtaining information on trends of increase or decrease over time of these variables. From the relationship between these two variables, it is possible to make projections of situations of scarcity water resources in watersheds. The objective of this work was to evaluate the occurrence of temporal trends of precipitation and flow between 1995 and 2011 in the upper Aracuai River Basin-MG, as well as to analyze the relationship between the flow and precipitation regimes. e relationship between monthly flow and rainfall was characterized using a linear model. Time trend tests (Mann-Kendall) were applied to the time series of precipitation (P) and flow (Q). e results showed a strong correlation (r = 0.8) between monthly flow and precipitation, both showing a tendency to decrease over the period evaluated. The interannual variability and trend analysis of the Q/P coefficient indicate that the intensity of flow reduction is greater than that of precipitation, indicating that land use and occupation may also be affecting the reduction in flow in the region. The results can contribute to the planning of the use of water resources in the region.