THE INFLUENCE OF HIGHWAY BR262 ON THE LOSS OF CERRADO VEGETATION COVER IN SOUTHWESTERN BRAZIL
Keywords:Distance effect, landscape ecology, habitat fragmentation, road effect zone
AbstractThe effects of a highway extending beyond the axis of the road, within regions with variable dimensions depending on the variables tested, are called “road effect zones”. The limits can vary according to the landscape and in areas where human occupation is more intense and, especially where settlements are formed along the roads, there is an accelerated rhythmof environmental degradation through destructive exploitation. Currently, only 35% of the Cerrado biome remain unchanged for the Brazilian remnants, and the southwestern part of the biome mostly suffers from deforestation. During the ‘80s, in the State of Mato Grosso do Sul, there was a high rate of colonization and as a result vast areas of native vegetation were replaced by agricultural lands, such as cash crops and pasture. The objective of this study was to estimate the evolution of deforestation in the cerrado within a road zone effect of 200 km on the highway BR-262, between Campo Grande and Miranda (Mato Grosso do Sul State, Brazil). The effects were evaluated by using temporal and spatial analysis with geotechnology techniques and remote sensing data. Our hypotheses were that there is an evolution of deforestation since the 1980s, and that deforestation is more intense near the highway. The study area comprises 9 km (divided in three different distances) for each side of the road. This road begins in Brazil's central highlands and extends into the Pantanal, an environmentally important area. Based on satellite images from 1985 and 2001 we could estimate a 32.6% loss of cerrado along the highway. In addition, we found that the road impacts the distribution of vegetation cover, with pasture growing near the road, and forest cover growing further away. The roads are considered an accelerating factor to habitat degradation.