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Land use and land cover (LULC) changes have severely threatened ecological and economic sustainability in highland Ethiopia. A clear insight into its extent and rate is, therefore, a crucial step for effective land use planning and decision making. The main objective of this study was to analyse the nature of LULC change and its impacts in north‐western highland Ethiopia over the last four decades, using the integrated approach of remote sensing and geographic information system in combination with field data. Multidate Landsat images were used for spatio‐temporal change detection through the help of ArcGIS 10.3 and ERDAS IMAGINE 2014 software. A pixel‐based statistical analysis was used to measure class‐to‐class changes and total losses and gains of each LULC class during the study period. The results show that a significant and widespread change of LULC has occurred in the study area during the period 1973–2016. The cropland, grassland, and shrubland were the dominant LULC types taking more than 95% in total over the entire study period. The cropland and built‐up land showed a significant increase from 1973 to 2016, whereas grassland and shrubland decreased gradually over the same time period. The LULC change in the study area has caused severe environmental degradation, which in turn has affected ecological sustainability, agricultural productivity, food security, and rural livelihoods. The results of this study are expected to provide local‐level current information on the extent, rate, and impacts of LULC change for decision makers seeking to ensure ecological, social, and economic sustainability.

Watershed degradation in Ethiopia has become a major environmental threat and caused significant damages both in the natural environment and the development of human society. This paper assesses an overview of the extent, causes, and effects of watershed degradation and the management actions in north-western highland Ethiopia, taking the Rib watershed as a case study site. The data were collected from field observations, interviews, and questionnaire surveys administered to 210 farmers. The results show that watershed degradation is a serious and widespread problem in the study site. The major causes of watershed degradation include population growth, uncontrolled grazing, unsustainable land use and management practices, and weak land ownership system. Watershed degradation, mainly in the form of soil erosion, has adversely reduced agricultural production and worsened food insecurity and poverty in the study area. Various watershed management practices that combine structural and biological measures have been practiced to curb the problem. However, the farmers' decisions to adopt and implement the measures have been highly influenced by a range of socioeconomic, biophysical, and institutional factors. Access to support services, size of the farmland, educational level, and plot ownership were found to influence farmers' decisions positively at a statistically significant (P < 0.01) level. It needs efforts to create farmer environmental awareness and develop strong watershed management standards and guidelines. The watershed could benefit from hand in hand efforts of local farmers, concerned governmental agencies, and researchers.

Soil erosion caused by climate and land-use changes is one of the biggest environmental challenges in highland Ethiopia. The aim of this study was to assess the future soil erosion risks and evaluate the potential conservation measures in the Rib watershed, northwestern highland Ethiopia. We used the HadGEM2-ES model with a moderate greenhouse gas (GHG) concentration scenario (RCP4.5) to project the future climate. The future land-use patterns were predicted using the CA-Markov model. We integrated the RUSLE model with GIS to estimate the spatial distribution of soil loss and identify erosion risk areas. We found that the Rib watershed is highly vulnerable to future climate and land-use changes, leading to a high soil erosion risk. Despite slight growth of forest cover during the study period, the total soil loss for the watershed was estimated to be 7.93 × 10 6 t year −1 in 2017 and was predicted to increase to 9.75 × 10 6 t year −1 in 2050, an increase of about 23%. The increase in forest cover was due to the expansion of the area of eucalyptus plantations which are more prone to erosion. Moreover, field survey showed that the residual native forests are sparsely vegetated and mostly used for cattle grazing, increasing the erosion risk even more. In contrast, the combined use of afforestation with native trees and physical soil conservation measures in the upper areas of the catchment could decrease soil loss by 62%. Our results stress the importance of combining soil conservation measures, including converting eucalyptus plantations to native forests, to mitigate the effects of future climate change and increased agricultural production on soil erosion.