Natural vulnerability of water resources in the Formoso River basin, Northern Brazil

The natural vulnerability characterization provides fundamental support for identification of areas more susceptible from the hydrology point of view, assuring the maintenance of water resource features. In this context, this study aimed to characterize the natural vulnerability of water resources b...

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Bibliographic Details
Authors: Oliveira, Tamires Alves, Viola, Marcelo Ribeiro, Mello, Carlos Rogerio de, Giongo, Marcos, Coelho, Gilberto
Format: article
Status:Published version
Publication Date:2015
Country:Brasil
Institution:Universidade Federal de Lavras (UFLA)
Repository:Repositório Institucional da UFLA
Language:English
OAI Identifier:oai:repositorio.ufla.br:1/15330
Online Access:https://repositorio.ufla.br/handle/handle/1/15330
Access Level:Open access
Keyword:Watersheds – Formoso River, State of Tocantins, Brazil
Water resources – Contamination
Streamflow
Aquifers
Bacias hidrográficas – Rio Formoso, Tocantins
Recursos hídricos – Contaminação
Vazões naturais
Aquíferos
Description
Summary:The natural vulnerability characterization provides fundamental support for identification of areas more susceptible from the hydrology point of view, assuring the maintenance of water resource features. In this context, this study aimed to characterize the natural vulnerability of water resources based on long-term streamflows, base flow and aquifers’ susceptibility to contamination, for Formoso River basin, located in southwestern Tocantins. For that, subdivision by level 5 Ottobasins and discharge and precipitation data sets, both available from the “Brazilian National Water Agency”, and the geological map developed by “Tocantins State Bureau of Planning” (SEPLAN) were used. The final natural vulnerability of water resources presented degrees varying from low to very high. Areas with lower vulnerability were observed in the basin headwaters, mainly due to the greatest both long-term (SYqlt) and 90% of the exceedance (SY90%) specific discharges. “High” vulnerability were identified in most of the middle basin course while “Very High” vulnerability in the lower basin course given by lower SYqlt and SY90% and by the occurrence of the alluvial aquifers which present high natural susceptibility to contamination.