Abstract

Land use land cover (LULC) dynamics are a widespread, accelerating, and significant process driven by human actions. LULC changes analysis is one of the most precise techniques to understand how land was used in the past, what types of changes are to be expected in the future, as well as the forces and processes behind the changes. This study was carried out to evaluate the historical and future trends as well as driving forces of LULC changes in Somodo watershed South Western, Ethiopia. It was accompanied using satellite image of Landsat5 TM 1985 and 1995, Landsat7 ETM+ 1999, 2005 and Landsat8 OLI/TIROS 2017. In addition, field observations, Key informant interview (KII) and Focus Group Discussion (FGD) were also conducted. ERDAS Imagine 9.1, QGIS 2.18 and IDRSI Selva 17.00, software were used for satellite image processing, map preparation, and LULC change prediction respectively. During the 32 year period between 1985 and 2017, the proportion of area covered by forest and agriculture was decreased by 60.57 ha (12.7%) and 5.22 ha (1.1%) respectively. In contrast, home garden Agroforestry/settlement and grassland were increased by 49.77 ha (7.5%) and 16.02 ha (6.7%) respectively. If the existing rate of LULC change lasts, in 2029 agriculture and forestland are predicted to increase by 91.24 ha and 20.52 ha respectively, while grassland and home garden Agroforestry/settlement are predicted to decrease by 99.97 ha and 11.79 ha respectively. LULC change in the study area is an outcome of several proximate and underlying drivers. The major proximate driving forces of LULC change in the watershed are illegal logging and fuel wood extraction, Expansion of plantation, expansion of settlement, agricultural expansion, and construction of infrastructures. Demographic, Economic, Technological, Institution and policy, and Biophysical factors constitute the major underlying drivers of LULC change in the study area. Population growth is the major underlying cause for LULC change in the study area. Then, Participatory Forest Management through plantation and community nursery expansion is required for forest cover improvement in the watershed. This study also suggests further study on the impact of LULC change in the area.

Key words: Drivers, geographic information system (GIS), Land use/Land cover Change prediction, Somodo Watershed.