The present study was developed in a test field of an area known as "Terra do Meio". It is located in the municipal districts of Altamira and São Félix do Xingu, State of Pará. The general objective of this work was to analyze the relationship between deforestation and hotspots in the period from 1998 to 2002. The specific objectives were to verify whether there is any relationship between the size of the deforested area and the incidence of hotspots; as well as to find out whether the process of obtaining and geopositioning of NOAA images interferes in the overlapping of hotspots with polygons of deforestation. The data were analyzed in a geographical information system (S.I.G.). For determining the relation between the variables, two regression analyses were carried out: linear and 2nd degree polynomial. Once the equations were obtained, a test of significance of the linear and quadratic components was accomplished. Then, the coefficient of determination was calculated, in order to choose the best-fit equation to the data distribution. Positive relationship was found within the analyzed data. The relationship was greater when hotspots and increase in deforestation in the same period were overlapped. The largest deforestation areas showed more consistent results. The linear and quadratic components of the resulting equations were more significant with the use of "t" test. The equations obtained by the method of linear regression were chosen to represent the data distribution, because they are considered simpler. The larger number of overlapping between the hotspots and deforestation in areas of more than 100 hectares suggests that the deforestation size directly influences fire detection. The obtaining and geopositioning of NOAA images do not interfere in this overlapping. The results suggest that the products generated by NOAA satellites are suitable for hotspot detection. However, they are imprecise when it comes to locating and dimensioning the affected areas.
Geopositioning; Amazônia; Terra do Meio
