Assessment of Deforestation using GIS & RS: A Case Study of Welmera Woreda West Shoa Zone Oromia Regional State

Abstract

The aim of this study was to assess deforestation acceleration change for the last 20 years from 2000 to 2020 using remote sensing and GIS in case of Welmera Woreda west shoa zone Oromia regional state. High resolution Lands at imagery of different three years is the main input data of the study.NDVI2 algorithm and unsupervised classification methods are used during data analysis. The study area divided in to four major land use land cover classes; Vegetation cover, Farmland, Urban area and Barrel and. Forest Priority Area that covers the total area around 21094.3ha in 2000 from the total area coverage 104719.5 ha and Post classification comparison change detection methods and NDVI image differencing were employed. The major land use land cover types in the study area have been identified during unsupervised classification method by ERDAS imagine as: Vegetation cover, Farmland, Urban area, and Barre land. The study made use of Landsat7 image of the year 2000 and Landsat8 for 2013and 2020 to assess forest cover changes and rate of deforestation during the different periods and the type of land cover to which the forest is changed to Farmland and urbanization. In addition Multi Criteria Evaluation in a GIS environment was used to come up with the final deforested area map. The result of change detection analysis revealed that the area had remarkable land- use land cover changes in general and forest cover changed to farmland and urban area. Specifically, the forest cover land declined from 21094.3 ha in 2000 to 19413.2 ha in 2013and dropped to 18431.9 ha in the year 2020 in the study area. Based on the forest cover areas of the year2000, 2013and 2020 of study area, about 1680.4ha between 2000 to 2013, 981.9ha between 2013 to2020 and 2662.4 ha between 2000 to 2020 was cleared respectively. The problem of forest cover change according to the finding is directly linked with the activity of the society such as expansion of Farmland, Urbanization, and others. In order to understand the impact of forest cover change on environment corrective measures are suggested under recommendation.