Diagnóstico das áreas de preservação permanente das microbacias hidrográficas do município de Bandeirantes – Paraná

Abstract

ResumoA expansão das fronteiras agrícolas, o desenvolvimento industrial e o aumento dos índices populacionais demandaram aumentos substanciais na produção de alimentos. Estes fatores levaram à degradação crescente dos recursos naturais. A devastação das áreas de florestas ao longo dos rios e córregos, entorno das nascentes e topos de morros, no passado, obrigam sua recomposição, por força de lei, como áreas de preservação permanente (APP). Este trabalho teve por objetivo delimitar as microbacias do município de Bandeirantes, mensurar as áreas de preservação permanente, total e existentes, ao longo dos cursos d'água, nascentes e topo de morros e identificar o uso conflitivo destas áreas. Utilizou-se o sistema de informação geográfica SPRING 4.1, imagem do Landsat ETM+, bandas 2, 3, 4 e 5, base cartográfica do IBGE, escala 1:50000 e fotografias aéreas, escala 1:25000. Verificou-se que o município apresenta 8,6% das APPs com mata ciliar, sendo 11,38%, 8,21% e 5,25% referentes a rios, córregos e nascentes, respectivamente. As APPS referentes a topo de morros e declividades superiores a 100% têm área equivalente a 24,94 ha e 8,7 ha, no entanto 100% destas áreas encontram-se sem mata. As microbacias que apresentaram menor índice de APP foram aquelas com melhor aptidão agrícola. Palavras-chave: Mata ciliar, uso agrícola, sistema de informação geográfica (SIG) AbstractThe expansion of the agricultural limits, the industrial development and the increase of populations indexes demanded substantial increases in the production of victuals. These factors took to the growing degradation of the natural resources. The devastation of the areas of forests along the rivers and streams, around the riverhead and tops of hills, in the past, they force its recomposition, for law force, as permanent preservation areas (PPA's). This work had for objective to define the watersheds of the municipal district of Bandeirantes -PR, Brazil, to measure the permanent preservation areas, total and existent, along the courses of water, riverhead and top of hills and to identify the conflict use of the soil in these areas. The geographical information system was used SPRING 4.1, image of Landsat ETM+, bands 2, 3, 4 and 5, cartographic base of the IBGE, scale 1:50000 and aerial pictures, scale 1:25000. It was verified that the municipal district presents 8,6% of PPA's with ciliary forest, being 11,38%, referring 8,21% and 5,25% to rivers, streams and riverhead, respectively. Referring PPA's meets of top of hills and in superiors slopes at 100%, they have equivalent area for 24,94 ha and 8,7 ha, however 100% of these areas are without forest. The watersheds that presented smaller index of PPA's was those with better agricultural aptitude.

Mapping of slopes for the operation of agricultural harvesters in Bandeirantes Municipality (PR)

“…The predominant types of soils in the municipality are Red Yellow Latosol (LV -Latossolo Vermelho) and Red Acrisol (PV -Argissolo Vermelho) (MAACK, 1968;EMBRAPA, 2013). The area is kept in pasture and tillage, especially the crops of sugarcane, soybeans, corn, wheat, alfalfa, cotton, thin grape and coffee (REIS et al, 2009). The cartographic base, consisting of charts drawn up by the Brazilian Institute of Geography and Statistics (IBGE) at 1:50,000 scale, using UTM projection, the Imbituba, SC vertical datum, and the regional geodetic system SAD 69.…”

Land use in Permanent Preservation Areas of Grande River (MG)

“…Ecological restoration is an alternative to reestablish environmental services provided by these areas (Reis et al, 2009;Valle et al, 2010;Moreira et al, 2015). However, the reduction of areas to be restored by part of Article 61-A of Law 12,727 (Brasil, 2012b) to those areas where there is consolidated use (anthropic occupation pre-existing on July 22, 2008) may compromise the recovery of services provided by PPAs (Tambosi et al, 2015).…”

“…Geographic information systems (GIS), in turn, are capable of linking information to geographic space, providing resources for precise and detailed modeling of the Earth's surface (Oliveira et al, 2008). The integrated use of RS and GIS, in addition to advances in these areas of knowledge, has led to quicker and more efficient mapping of land use and coverage, assisting in decision-making (Reis et al, 2009;Messias, 2012;Moreira et al, 2015).…”

“…The Brazilian Forestry Code (Brasil, 1965) established these areas as Permanent Preservation Areas (PPAs), since they are located in extremely important locations from an environmental perspective and provide several ecosystem services (Reis et al, 2009;Valle et al, 2010). PPAs are […] areas covered or not by native vegetation, with the environmental function of preserving water resources, landscape, geological stability, biodiversity, the gene flow of fauna and flora, protecting the soil and ensuring the well-being of human populations (Brasil, 2012a).…”

Land use and occupation analysis of Permanent Preservation Areas in Lavras County, MG

“…The fast population growth associated with the fast agricultural and industrial expansion caused a severe ecosystem degradation in the whole planet, reflecting on the quality of life of the populations and stability of natural resources (REIS et al, 2009). The expansion of new agricultural frontiers causes partial removal of the natural vegetation cover by areas destined to agriculture and pasture, changing natural ecosystems into an agrosystem (BOLFE et al, 2008).…”