Identificação de áreas degradadas: análises de tendências de variáveis espectrais no semiárido.

Abstract

The Brazilian demographic explosion that occurred after 1960 altered the land surface composition logistics in the territory, promoting an overcoming of the urban population over the rural one. The changes made by urbanization disregarded the naturalness of the hydrological systems (of the environment without modification), not only by the deflecting the watercourses, but also by altering the use and cover of the soil. The hydrological processes were considerably impacted due to the buildings, paving, waterproofing, plumbing and rectification of the watercourses. The new hydrological responses in urban basins are capable of generating the main natural disasters that plague the Brazilian territory, such as droughts and floods. The traditional approach to urban drainage has proved to be insufficient to contain disasters, because it is based on the principle of immediate conduction of wastewater. Otherwise the sustainable urban drainage (SUDS) methodology proved to be more efficient, because is based on the resumption of pre-urbanized condition of watercourses, rationalization of water use, and control of potential runoff generators. In this sense, the present work aims to verify the feasibility of applying two techniques of SUDS, rainwater harvesting system and green roof, to promote the reduction of runoff in a kindergarten and elementary school of the Complexo Habitacional Aluízio in Campina Grande - PB; as well as by analyzing the benefits of using the techniques to fully guarantee the social function of the building and the monetary costs of its application. To obtain the results the following simulations were necessary: reservoir sizing through the Rippl method and the simulations; verification of the runoff damping through the Storm Water Management Model (SWMM) hydrological model; verification of temperature reduction after installation of vegetation cover, using the program JARDIM 1.1. It is concluded that despite the high costs of implementation, the application of both techniques is favorable to the building, as it reduces the temperatures inside the building, decreases the flow volume by 23%, besides the installation of a reservoir capable of suppressing 15.7 m³ of water volume for monthly supply.