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Spatio-temporal dynamics of selective logging in the state of Mato Grosso between 1992 and 2016

Abstract

Selective logging is a forestry activity that includes harvesting a group of tree species in native forests, usually those of higher value or commercial interest. Selective logging can be carried out legally, in forest management areas and forest areas previously authorized for deforestation, or illegally, in any other unauthorized cases that occur in a predatory manner. In this study, the spatiotemporal dynamic of selectively logged forests in the state of Mato Grosso was assessed based on a time-series (from 1992 to 2016) of logged forests detected using remotely sensed data. Visual interpretation and semi-automatic classification of Landsat imagery were used to detect forests impacted by selective logging activities in the study area. Based on the results, it was estimated that 41,926 km2 of native forests were selectively logged at least once between 1992 and 2016 in the state of Mato Grosso, an annual average of 1,747 km2. Selectively logged forests detected showing persistent or recurrent forest disturbances were more frequently observed in the most recent years of this analysis. Most of the selectively logged forests in the study area and period have not been deforested by 2016. It indicates that selective logging is a dissociated phenomenon with deforestation in the state of Mato Grosso. It was also observed that an average of 18 km2.year-1 and 268.18 km2.year-1 of native forests was selectively logged within Conservation Units and Indigenous Lands between 1992 and 2016. A significant tendency to increase or decrease logging activities within those protected areas in the analyzed period was not observed. Selectively logged forests were persistently detected in the old timber centers located in the central-northern region of the state of Mato Grosso, showing, potentially, new cutting cycles in those previously logged forests. More recently, selective logging activities have reached the last native forest frontier in northwestern Mato Grosso. Finally, it was concluded that selective logging is annually disturbing a considerable extension of native forests in the state of Mato Grosso and, therefore, needs to be adequately considered and monitored by environmental agencies due to its potential forest impacts and to support the definition of public policies to ensure the future sustainability of forest production in that state.

Keywords:
Forest disturbances; Tropical forest; Amazon; Remote Sensing; Geographic Information System

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