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Understanding the hydrologic regime, and monitoring runoff at the micro-basin scale is critical for understanding water availability, and for managing water resources in strategic biomes such as the cerrado. The objective of this research is to evaluate morphometric characteristics and the hydrologic regime and determine their relationships with soil characteristics and typical land-use in the cerrado biome. To reach this objective morphometric characterization, runoff and precipitation monitoring, and determination of the water retention curve were conducted in three micro-basins in the municipality of Campo Verde, Mato Grosso. These micro-basins each have a different, but regionally typical land-use and were selected strategically to represent this area of cerrado: agriculture, pasture and native vegetation. The results obtained allow for the analysis of the hydrologic regime throughout the period measured. Micro-basins with native vegetation and pasture, with greater altimetric range and more sandy soils, show greater erosion. Despite this, the micro-basin with pasture cover showed greater regulation of runoff. The micro-basin with agriculture showed less regularization of water flux due to the physical characteristics of the local soils. O conhecimento e monitoramento da vazão, assim como o entendimento do regime hidrológico a nível de microbacias tem sido relevante para se determinar a disponibilidade hídrica, assim como promover o gerenciamento dos recursos hídricos em biomas considerados estratégicos como o cerrado. Este trabalho foi desenvolvido com o objetivo de avaliar as características morfométricas e o regime hidrológico e sua relação com as características do solo bem como do seu uso em três microbacias no bioma cerrado. Para alcançar o objetivo proposto, fez-se a caracterização morfométrica, o monitoramento da vazão e da precipitação diária e elaboração da curva de permanência de três microbacias hidrográficas localizadas no município de Campo Verde-MT contemplando os seguintes usos: agricultura, pastagem e vegetação nativa. Essas bacias foram selecionadas estrategicamente por serem representativas dos principais sistemas de uso do solo na região de cerrado. Os resultados obtidos permitem ponderar que há diferença no regime hidrológico das microbacias hidrográficas ao longo do período analisado. As microbacias com vegetação nativa e com pastagem, por terem maior amplitude altimétrica, além de apresentarem solos de textura arenosa, são mais propensas à erosão hídrica. A microbacia com pastagem apresentou maior regularidade na vazão e, a microbacia com agricultura uma menor regularização do fluxo hidrológico em função das características físicas dos solos que compõe a microbacia.

The impacts of human activities on watersheds can change the quality and possible uses of water resources. In this context, we evaluated the flows of dissolved organic carbon (DOC) and nitrate (NO3) in the surface waters of two micro-watersheds with different anthropic impacts. Water samples were collected from two micro-watersheds with different land uses (regenerated savanna and an agricultural site) from January 2014 to April 2015. In the rainy season, the samples were collected every 15 days, while in the dry season, samples were collected every 30 days. An automatic sampler in the stream collected the composed samples. Water flow was monitored with a sensor that measured the hydraulic load on the sill of the triangular spillway installed in each micro-watershed. The DOC and NO3 contents were analyze via UV-Vis spectrophotometry. The flow was estimated based on the DOC and NO3 flows and concentrations. The DOC concentrations were higher in the Cerrado micro-watershed; however, there was no difference in NO3 concentrations. In both watersheds, there was a significant increase in the concentrations of DOC and NO3 on rainy days, with was more pronounced in the agricultural watershed. The DOC and NO3 flows were higher in the micro-watershed with Cerrado vegetation on days with rain; while on days without rain, there was no difference. : The impacts of human activities on watersheds can alter the quality and possible uses of water resources. In this context, the objective of this study was to evaluate the flows of dissolved organic carbon (DOC) and nitrate (NO3) in the surface waters of two mini-watersheds with different anthropic impacts. Water samples were collected in two mini-watersheds with different soil use (regenerated savanna and an agricultural area) from January 2014 to April 2015. In the rainy season, the samples were collected every 15 days and in the dry period every month. The composite samples were collected by an automatic sampler in the stream. The water flow monitoring was performed with a sensor that measured the hydraulic load on the sill of the triangular spillway installed in each of the mini watershed. The DOC and NO3 contents were analyzed in a UV-Vis spectrophotometer. The flow was estimated with the values of flow and concentrations of DOC and NO3. COD concentrations are higher in the cerrado mini watershed, but there was no difference in NO3 concentrations. In both watersheds there is a significant increase in the concentration of DOC and NO3 on rainy days, with this increase being greater in the agricultural watershed. COD and NO3 flows are higher in the mini-watershed with cerrado vegetation in the presence of rainfall, but there was no difference in the absence of rainfall.