Abstract ID: 459

Quantifying land use/cover determinants under the role of official colonization areas at different spatial extents in Rondônia State

According to official figures, human occupation has caused the loss of 17% of forest reserves in the Brazilian Amazonia, being Rondonia State the fourth most deforested one in the region. During the last four decades official colonization projects together with spontaneous migration resulted in high rates of deforestation. Although, several studies have been developed in this region, quantification of land use/cover determinants at fine spatial scales are still poorly understood. In this context, the present study aims to quantify land use/cover determinants at two different spatial extents in Rondônia State. We analyzed areas inside official agrarian projects and outside (spontaneous colonization) considering their age of colonization. The first spatial extent included two municipalities in the frontier of colonization (local analysis). By enlarging the previous area the second extent included a total 30 municipalities in the north of Rondônia (regional analysis). Land cover maps, accessibility measures, conservation units, socioeconomic and biophysical data were used as input for descriptive statistics and logistic regression analysis. The local analysis indicates a much higher amount of deforestation inside the agrarian projects than in spontaneous areas. In addition, the clearing of forest remnants is more significant in older agrarian projects. The regression analysis indicated cost distance to urban areas as a strong determinant of deforested patterns at both spatial extents. Similar results were recently reported in the literature also at a broader scale of analysis. Conservation units and socioeconomic variables have also presented a significant importance. Different from other determinants socioeconomic and biophysical aspects vary considerably when areas outside the agrarian projects are disregarded. This may indicate the demographic concentration and the importance of land use planning previously to occupation. At regional scale descriptive statistics showed comparable deforestation rates along the time inside and outside agrarian projects, but with higher amounts of total deforestation mainly inside the older projects, as also observed in the local analysis. Preliminary results at the regional extent indicate that cost distance measures determine land use/cover as much as socioeconomic variables, but further analysis must be done to confirm these results.

Session:  LCLUC and Human Dimensions - Land-use/land-cover change models and scenarios at multiple scales for Amazonia.

Presentation Type:  Poster