Revista de Ciências Agrárias (Oct 2021)
Use of the linear spectral mixture model in the Saracá-Taquera National Forest
Abstract
The Saracá-Taquera Conservation Unit is one of the most exuberant National Forests, rich in biodiversity and with a high potential for the use of natural resources. The objective of this study was to identify signs from forest exploiting and activities with potential for degradation in the Saracá-Taquera National Forest (FLONA-ST), using the linear spectral mixture model (LSMM) in an image recorded in 2020. The study was carried out at FLONA-ST, located in the mesoregion of the Lower Amazon. The images were acquired with the Geological Service of the United States. The collected scenes, 228/061 and 229/061, were submitted to compositions of bands 6, 5, and 4 of Landsat 8, mosaic, and the image clipping corresponding to the area of FLONA. The LSMM was applied and the Spectral Index of Forest Degradation (DEGRADI) was determined. Then, the technique of slicing and vectoring of images was applied, for further classification based on visual interpretation. The use of LSMM and DEGRADI were able to identify the deforested areas in FLONA-ST. In general, FLONA was predominant in areas covered with dense and heterogeneous vegetation. However, areas with exposed soil were observed in the central, north, northeast, southeast, and south parts, whether intended for mining, agricultural activities, housing, or for the exploitation of forest resources in FLONA. The forest exploitation in FLONA was observed, mostly, within the Forest Management Units, where exploration caused by disordered and geometric selective logging was found.
