Brazilian cattles breeding has had a negative evaluation, by environment entities, due to the extension of land occupied with pasture. To answer questions in this context, the Ministry of Agriculture determined the establishment of a program with the objective of describing the current situation and of carrying out an annual monitoring of the expansion of pasture areas. The results should ensure more effective scrutiny in the audits made by the official entities responsible for these areas. In the second semester of 2009, a pilot area, covering 6 counties in the Southeast of Pará state, was mapped and, in 2010, this area was monitored with the purpose of identifying possible expansion of pasture land in this year. The mapping and the monitoring were realized with Landsat5(TM) images. The work consisted in the analysis and interpretation of images to determine the polygons of pasture areas, using software of image processing and cartographic edition. It was found that 23% of the region that was mapped in 2009 was farmland, 98.4% of which are occupied by livestock, and 1.6% is cultivations. The monitoring findings in 2010 indicated an increase of 3% in the pasture areas in relation to 2009. This makes it succeeded in establishing a trustworthy quantification of the areas that are being deforested to give place to cattle raising activities; thus, providing data that will help set up governmental actions to inhibit the negative impact caused by these activities.Pages: 169-17
