Diagnóstico do uso e ocupação do solo da microbacia hidrográfica do riacho Itararé zona sudeste de Teresina

Abstract

The present study focuses on the environmental issues involved in the use and occupation of the soil, located in a watershed of the municipality of Teresina, capital of the State of Piauí. This study is justified by the fact that the accelerated growth of the city in the last years has caused several disorders related to the floods, caused several social and environmental impacts in the region. Through this problem, this study aimed to perform a diagnosis of the use and occupation of the soil and its reflec tions on the surface drainage of the Itararé stream watershed in the southeast of Teresina PI and can be used as a planning and management tool of the area. According to Lima, (2016) the systemic approach or geosystems serves as a basis for territorial pla nning purposes and stresses the importance of to include variables such as land use and occupation for the study of natural systems. It is of an applied nature, with a qualitative approach involving the treatment of several soil cover data and the necessar y processes for the hydrological model of the hydrographic basin. In order to acquire the land use and land cover data, we used the QGis geoprocessing software, a powerful free tool, and the hydrological simulation was chosen using the Soil Conservation Se rvice (SCS) method available in the HEC HMS software. With these two softwares and with the support of empirical formulas, it was possible to relate the soil cover with a waterproofing level and its reflections in the peak flow of the river basin. For the simulation, the recurrence times chosen were 1, 2, 5, 10, 20 and 50 years, and for each year the following flow values were obtained: 46.1; 60.1; 83.5, 110, 137.1 and 180.5 m 3 / s. with these data it became possible to relate the soil cover to the surfa ce runoff of the hydrographic basin and later the effects of urbanization on the peak flow and its possible solutions, being in this case the public power the articulation of new mitigation measures, such as for example the application of existing standard s. Finally, we conclude that land use and occupation can contribute significantly to the increase in the peak flow of the study watershed, but it can be greatly reduced if the measures proposed in both the legislation and in this study are put into practic e by the managers of the municipality , certain that, in the same way, it can also increase a lot if they are not put into practice, thus causing several socio environmental damages in the area.