Análise temporal do uso da terra em Balsa Nova - PR

Abstract

This study aimed to change detection in the land-use and land-cover that occurred between the years 1980 to 2009, in an area of 10,370.0 hectares, located in the Balsa Nova county, Paraná. It was used photoimages (1980) with spatial resolution of 2 m, orthoimages (2000) with spatial resolution of 0.84 and satellite images Landsat 5 TM (2001 and 2009) with spatial resolution of 30 m. It was elaborated land-use and land-cover maps for the years 1980 and 2000, performed by on-screen digitalization to identify seven and eight classes, respectively. There was no area alteration in the class Natural Forest, while the Forest Planted area has risen by 554.1%. The 1980/2000 dynamic map of land-use and land-cover, that was prepared by post-classification comparison and with sixteen thematic categories, presented unreliable results, due to geometric errors in the mosaic of 1980, including differences in interpretation of the classes subjects in the two dates. Due to unavailability of satellite images of 2000, free of clouds and for near the same date of photo and ortoimages, for the change map (2001-2009) it was used 2001 Landsat image and the algorithm of Radiometric Rotation Controlled Axis of Not Change (RCEN). The 2000 land-use and land-cover map was resampled to 30 meters and it was crossed, by the algorithm of post-classification comparison, with the change map (2001-2009), resulting the 2001-2009 dynamic map of the land-use and land-cover. Field work was carried out in order to collect field sample points for validation of the 2001-2009 change map and subsequent update of the 2000 land-use and land-cover map for the 2009 dynamic map of the land-use and land-cover. The technique RCEN dispenses less processing time than the visual interpretation, but requires sample collection points in the field to confirm the thematic classes that undergo change; it is a technique for rapid use, particularly for thematic classes that do not have confusion. The areas occupied by Natural Forest and Planted Forest classes reduced in the period 2001-2009.