Desempenho do LISEM para a modelagem hidrológica em bacia hidrográfica com diferentes fontes de informações

Abstract

The need to carry out risk management in areas subject to extreme rainfall events, combined with the lack of hydrological data, implies the need to seek alternative methods for predicting the impacts generated by such events. One of the alternatives is the LImburg Soil Model Erosion (LISEM) hydrological model. In this work, LISEM was applied to monitored precipitation events, which occurred in a basin with approximately 0.70Km², located in Canguçu/RS. The objective was to evaluate the model's performance in estimating ESD hydrographs originating from extreme rainfall events, through changes in the level of detail of the input parameters, in a small monitored watershed, located near the source of the Pelotas stream. A detailed topographic survey of the area was carried out, which enabled the application of a digital elevation model with high spatial resolution. Remote sensing techniques and soil sampling were also used to obtain the model's input parameters. The results showed that, for the basin under study, the LISEM performance using more detailed soil and cover data was not superior to that using the parameters suggested by the model manual. The topographic detailing of the watercourse showed, for this basin, an improvement in the ESD results, in the spatial resolutions of 10m and 30m.