Assessment of land use/cover, ecosystem services and rural livelihoods changes: the case of walga watershed, south west shewa, Ethiopia

Abstract

Understanding land use/cover and associated ecosystem services and livelihood strategies are becoming an important discussion point at local, regional and global levels. The issue is particularly so in developing countries like Ethiopia where anthropogenic driven land use/cover changes are apparent. These studies aims at detecting land use/cover change (LULC) over a period of 30 years and assess associated ecosystem services and livelihood strategies changes at Walga watershed South West Shewa, Oromia regional state. Remote sensing was employed to quantify land use/cover for past three decades (1985-2015) and household survey was employed for collecting associated changes in ecosystem services (ES) and livelihood strategies in the study area. The result shows that there was a drastic shrink in forest, grazing land, water body and shrub land between1985-2015. For instances, forest, grazing land, water body and shrub land loss were estimated to be -3329ha, -278ha, -27ha and -424ha respectively, while crop and enset (Ensete ventricosum) farmlands, settlements and degraded lands were increased at the expense of the forest, grazing, water bodies and shrub land cover types by 1631ha, 1543ha, 122ha and 763ha respectively. A dramatic change of forest conversion to crop and enset farmlands, degraded land and settlements were observed in the study area. The implication of these LULC changes which assessed by household survey revealed that there was extreme change in ES which provided by each LULC in the study area. During the first 15 years of the study period forest was ranked as major source of soil and water conservation, timber, fuel wood, fodder, recreation, climate regulation and ecotourism, crop farmland as a source of food, water body as source of recreation and ecotourism, spiritual services, grazing land as source of fodder; however in the current period the services of ecosystem losses due forest degradation, shortage of grazing land and soil erosion problem in the area, inclination to mainly rely on Enset farming as major source of food and fodder were observed. The total simultaneous change regulation and cultural services were showed strong positive correlation with land cover change in area in-contrary to provision services which shows weak correlation due to high coverage of land degradation results fertility loss in the area. Likewise, the livelihoods of local community shows similar trend as a result of LULC change. The result shows the livelihood strategies of the households had changed from sole farm dependent livelihood to mixed livelihoods strategies. In general there was a drastic change in LULC of Walga watershed for past three decades which has brought about a temporal change in ecosystem services and the livelihood strategies of the local communities