A Look at Amazon Basin Seasonal Dynamics with the Biophysical ...

Changes in land use in the city of Manaus and adjacent areas of the Br 174 highwayMoreira, M. P., Venticinque, E.M., Albernaz, A.L.Projeto Dinâmica Biológica de Fragmentos Florestais – Instituto Nacional de Pesquisas daAmazônia / INPAEndereço: PDBFF/InpaAv. André Araújo, 1753 – Aleixo – Manaus/AMCaixa postal 478 - CEP:69011-970e-mail: pinguela@inpa.gov.brHistorically, changes in land use patterns in Brazilian Legal Amazon have been stimulatedby Government interventions through public policies such as road building, colonizationprojects and economic subsidies to industrial activities. In Central Amazon, mainly in areasaround Manaus, the occupation process was initiated with the rubber exploitation cycle, andwas later accelerated by the creation of the Free Commercial zone and implementation ofthe industrial district, accompanied by an agricultural program. These incentives havegenerated a intense demographic flux to this region. The present study aims to evaluate thedynamics of the deforestation and land use changes in the area around Manaus and alongthe nearby part of the BR-174, by using Landsat TM5 images from 1986, 1992 and 1997.The study area included 6825 Km 2 , in a rectangular shape of 105 x 65 km. Mapping of landuse and natural vegetation cover was made using supervised classification by maximumlikelihood classifier in the IDRISI 32 software. After classifying, the area of each class wascalculated for each of the following: mature forest; second growth, and urban/deforestedareas, and “other” (e.g. water, open natural vegetation areas) for the three images. Forestedareas have been reduced 3.3% in 1992 and 1.8% in 1997. Second growth areas increasedfrom 1986 to 1992 (7%), and was slightly reduced in 1997 (less than 1%). Urban areasincreased 66% from 1986 to 1992, and 9% from 1992 to 1997. These results make it clearthe strong impacts of economic subsidies to the region during the 1980s, and a diminutionin the rhythm of deforestation and urbanization from 1992 to 1997. Despite thedevelopment model based on these subsidies be considered one of the reasons of low forestlosses in the State of Amazonas, our results show that at a more local scale, aroundManaus, they have had a drastic impact, mainly through promoting the urbanizationprocess.