IWRA Proceedings

AbstractINTRODUCTION Many phenomena that occur in Amazonia affect the environment of the region and, in some cases, the whole globe. Some examples are: the carbon sequestration accomplished by the forest; the energy fluxes between soil-vegetation-atmosphere, which affect the climate dynamic; and also the floodplain dynamics that influences the discharge in some points of the Amazon River and its tributaries. In those cases mentioned before, water plays a crucial role. On the other hand, Amazon basin suffers a number of human interventions that can affect its environment. For example, Brazilian government intends to build hydroelectric plants in Amazonia to transform the region in an important energy source for the country. In addition, the region is under process of deforestation and, in the future, can be affected by the global warming. As described before, hydrological cycle is related to several issues: environmental equilibrium, energy generation, water resources management, deforestation and climate change impact. These matters justify the need to understand the hydrological processes observed in the basin. The higher our knowledge about the hydrological cycle in Amazon the better our capacity to manage its water resources. OBJECTIVE The objective of this work is to analyze the major hydrological processes of the Amazon basin: canopy interception, evapotranspiration, soil moisture and flow generation. METHODS It’s possible to achieve this objective by using either mathematical models or field measurements. Mathematical models allow us to have a large scale view of the processes in contrast with field measurements which give a local view. In this work, we have used a large scale hydrological model called MGB- IPH, which is distributed by cells. Each cell is divided into blocks, patches, which are formed by the combination of land use, vegetation, and soil type. The study was accomplished at Madeira River Basin, which is 1,420,000 km2 large. Madeira River is the most important tributary of the Amazon River and lies in Brazil, Bolivia and Peru. RESULTS AND CONCLUSION The simulations with MGB-IPH showed a good agreement between recorded and simulated discharges. These results indicate that the hydrometeorological data and the model parameterization are suitable to represent the rainfall-runoff processes at the Madeira River basin. In addition, the hydrological processes estimated with the model were similar to the values measured by other researches in Amazonia. The model simulations helped to improve the knowledge about hydrological processes in the region. These results encourage the use of MGB-IPH model to evaluate the impact of deforestation and climate change over the hydrological processes. The hydrological simulations can also help the water resources management in the region.