Dinâmica da paisagem na microbacia hidrográfica do Rio Mojuí, Oeste do Estado do Pará

• Autor(a) principal: Silva, Hugo Amancio Sales
• Data de Publicação: 2014
• Outros Autores: Campos, Sergio [UNESP]
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://www.uftm.edu.br/revistaeletronica/index.php/rbcti/article/view/717; http://hdl.handle.net/11449/140785
• topic: Landscape dynamici; Mojuí river; Watershed; Landsat images; Dinâmica na paisagem; Rio Mojuí; Bacia hidrográfica; Imagens LANDSAT

Currently, conservation issues have been discussed with great emphasis by society in general, especially on the Amazon landscape. Within this context is Mojuí River watershed, located in the cities of Santarém and Belterra, in the state of Pará. This comes under constant exploration of natural resources, mainly due to conversion of forest areas into agricultural areas, mainly for soybeans cultivation. The aim of this study was to characterize and quantify mapping , semi -scale detail , the areas of vegetation cover classes and land use in the period of 11 years as use of LANDSAT , orbit / points 227/62 , TM bands 3 , 4:05 , for the years 1999 , 2005 and 2010 , the landscape dynamics in the region . The selection of images was determined considering the similar climatic period, with the same lighting conditions and cloud cover. The boundaries of the basin were established by dividers that form the topographic area that drains to a specific point. Based on the data obtained in the field survey and with the support of photointerpretation the scenes of the sensors in the years established by research, has defined a thematic caption for vegetation classification and land use in the basin, identified seven forms of vegetation and land use in the catchment area of the basin. We defined the following classes of land cover: Rain Forest , Secondary Succession , Alluvial Rain Forest , Grassland , Degraded Grassland , Agriculture and Water Bodies . During the research it was observed that the Mojuí river watershed has lost 221.73 km² of natural vegetation cover (dense ombrophilous forest, alluvial dense ombrophilous forest). Until 1999 the dense ombrophilous forest class was the largest present at the watershed, however from 2005 on the agricultural class became the largest at that location, with an increase of approximately 518.11% of the initial research area. When the results were analyzed more specifically, it is highlighted that the agricultural area suffered a strong expansion during the time of the research, at the expense of other areas. The exception was the agricultural advance over the classes alluvial dense ombrophilous forest and waterbody, as theses classes are protected by law and unapropriated for mechanized agriculture.