Assessment of the Application Impact of the New Brazilian Forest Code on Urban Flood Management: Case Study in São Carlos and São José Do Rio Preto, São Paulo (PAP014821)
Lorena Avelina Rojas Gutierrez, Marcos Coutinho, Paulo Jorge Vaitsman Leal, José Luiz Albuquerque Filho, Javier Tomasella
Land use and Floods, landslides and erosion
The New Brazilian Forest Code (Law nº 12,651, of may 25, 2012), brought a new session (session III), about of protection system of urban green areas, across which the municipalities can: i) have the right of preemption to acquire relevant forest remnants; ii) to transform the Legal Reserves to urban green areas in urban expansion areas. Knowing the projection of growth of a city is possible to analyze the impact of implementing the new law on indicators of the pressure, state, impact and responde of the urban flood risks. The objective of this work was to apply spatial analysis of qualitative variables of impact on urban basin scale, in the context of urban green areas, from a multi-criteria approach to environmental vulnerability, considering populational growth and and expansion of urbanized spot on green areas around the cities of medium size, located in anthropics basins, with shortage of vegetation cover and history of occurrence of floods. In this sense, are presented and discussed geothecnologics tools for the implementation of New Forest Code on flood management in the municipalities of São Carlos and São José do Rio Preto, State of São Paulo. The variables analyzed were: Normalized Difference Vegetation Index - NDVI, extracted of satellite images; areas susceptible to flooding, extracted of Digital Elevation Model by Height Above the Nearest Drainage - HAND algorithm; chart of slope; urban expansion areas and areas with restricted land use, determinate by environmental zoning contained in the Master Plan of the municipalities. From the perimeter of municipalities established a radius of delimitation of urban areas, according to the projection of the growth of urbanization. Predicting that cities will expand toward the surrounding areas, including green areas, with the transformation of Legal Reserves in green areas in urban expansion areas. It is known that definition of green areas in cities and its implementation is important not only for conservation of forest resources, but mainly to prevent encroachment on fragile or inadequate occupation areas where the presence of vegetation exercises relevant environmental services, such as stabilization of riverbanks, sediment retention, regulating flows, facilitating infiltration, among others, that prevent siltation, directly related to the flooding. It also prevents soil the soil sealing, mitigating local climate conditions and adverse effects of disasters such as floods, being essential to create conditions for the permanence of these remnants, especially in flood plains where there is still forest, and proper land use in the areas of urban expansion. Legal and practical function of civil defense intervention were also assessed, as the new governing law. Assessing the impact of the action of this agency in this context.