Agriculture, Ecosystems and Environment 139 (2010) 174–180 Contents lists available at ScienceDirect Agriculture, Ecosystems and Environment journal homepage: www.elsevier.com/locate/agee Land-use/cover dynamics in Northern Afar rangelands, Ethiopia Diress Tsegaye a,b,∗ , Stein R. Moe a , Paul Vedeld c , Ermias Aynekulu d a Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, 1432 ÅS, Norway b Department of Animal, Rangeland and Wildlife Sciences, Mekelle University, P.O. Box 231, Mekelle, Ethiopia c Department of International Environment and Development Studies, Noragric, Norwegian University of Life Sciences, P.O. Box 5003, 1432 ÅS, Norway d Center for Development Research (ZEF c), University of Bonn, Walter-Flex-Str. 3 53113 Bonn, Germany article info Article history: Received 13 January 2010 Received in revised form 26 July 2010 Accepted 27 July 2010 Available online 19 August 2010 Keywords: Afar pastoralists Agriculture Drought Dry-season grazing Livelihoods Vegetation cover abstract This study uses a combination of remote sensing data, field observations and information from local people to analyze the patterns and dynamics of land-use/cover changes for 35 years from 1972 to 2007 in the arid and semi-arid Northern Afar rangelands, Ethiopia. A pixel-based supervised image classification was used to map land-use/cover classes. People’s perceptions and ecological time-lines were used to explain the driving forces linked to the changes. A rapid reduction in woodland cover (97%) and grassland cover (88%) took place between 1972 and 2007. Bushland cover increased more than threefold, while the size of cultivated land increased more than eightfold. Bare land increased moderately, whereas bushy grassland and scrubland remained stable. According to accounts from local people, major events that largely explain the changes include: (1) severe droughts in 1973/74 and 1984/85; (2) increase in dry years during the last decade; and (3) immigration and increased sedentarization of pastoralists. If the present land-use/cover change were to continue, coupled with a drier climate, people’s livelihoods will be highly affected and the pastoral production system will be under increasing threat. © 2010 Elsevier B.V. All rights reserved. 1. Introduction An estimated 4.7 million km 2 grassland areas and 6 million km 2 of forests/woodland, have been converted to croplands worldwide since 1850 (Lambin et al., 2001, 2003). In recent years, African grassland, woodland, and other vegetated areas have increasingly been converted into cropland (Millennium Ecosystem Assessment, 2005). For instance, an estimated 3.4 million km 2 of woody vege- tation in dryland zones of Africa have become degraded through human activities such as agricultural expansion and deforestation (Kigomo, 2003). Land-use shifts caused by external and internal drivers have influenced many traditional resource management regimes in arid and semi-arid areas where often a pastoral way of life has been the tradition (Campbell et al., 2005; Reid et al., 2004). The equilibrium paradigm, which states that ecosystem regulation is maintained in a stable way through negative feedback mechanisms, guided most rangeland management policy until the 1970s (Briske et al., 2003). Based on the concept of ‘tragedy of the commons’ (Hardin, 1968), pastoralism was considered as an environmentally destruc- tive resource exploitation strategy that resulted in overstocking ∗ Corresponding author at: Department of Ecology and Natural Resource Man- agement, Norwegian University of Life Sciences, P.O. Box 5003, 1432 ÅS, Norway. Tel.: +47 64965793; fax: +47 64965801. E-mail addresses: diress.alemu@umb.no, diress62@yahoo.com (D. Tsegaye). and the disruption of a perceived ecological equilibrium. This dom- inant paradigm was increasingly criticized in the 1980s partly due to a growing concern that interventions based on equilib- rium assumptions were inappropriate for some pastoral systems (Behnke and Scoones, 1993; Ellis and Swift, 1988; Sandford, 1983). Current theoretical evidence indicates that both equilibrium and non-equilibrium dynamics occur in ecosystems across both spatial and temporal dimensions (Briske et al., 2005; Oba et al., 2000; Wessels et al., 2007). Although conclusive empirical evidence does not exist to terminate the debate, rangeland degradation is still a widely occurring phenomenon in many African rangelands, threatening national economic values and also the lifestyles of pas- toralists. Despite all the rhetoric and the policy discussions, the current pace of degradation is unprecedented both in arid and semi-arid areas (Millennium Ecosystem Assessment, 2005). There have been some studies of land-use/cover changes at regional or local levels, but they often deal exclusively with quan- tifying land-use/cover changes using remote sensing tools or they focus on causes of land-use/cover changes through socio-economic surveys. Mapping spatial changes using remote sensing tools gives quantitative descriptions but does not explain or provide under- standing of the relationship between the patterns of change and their driving forces (Olson et al., 2004). Some recent advances in remote sensing play a major role in linking social models with the spatial dynamics of land-use changes (e.g., Mottet et al., 2006; Serneels and Lambin, 2001; Serra et al., 2008). However, studies such as these linking land cover changes with drivers are rare 0167-8809/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.agee.2010.07.017