HR: 1340h
AN: PA33A-1022    [Abstracts]
TI: Reversing land degradation in the densely populated and semi-arid highlands of Tigray (Northern Ethiopia) – evidence from photomonitoring with 30 years interval
AU: * Nyssen, J
EM: jan@ethionet.et
AF: Department of Land Resources Management and Environmental Protection, P.O.Box 231, Mekelle, ET, Ethiopia
AU: * Nyssen, J
EM: jan@ethionet.et
AF: Ghent University, Geography Department, Krijgslaan 281, Gent, B 9000, Belgium
AU: Munro, R N
EM: munro@dial.pipex.com
AF: Old Abbey Associates, Chapelhill, Dirleton, Eas EH39 5HG, United Kingdom
AU: Poesen, J
EM: jean.poesen@geo.kuleuven.be
AF: Physical and Regional Geography Research Group, K.U. Leuven, Celestijnenlaan 200 E, Heverlee, B 3001, Belgium
AU: Deckers, J
EM: seppe.deckers@biw.kuleuven.be
AF: Department of Land Management and Economics, K.U. Leuven, Celestijnenlaan 200E, Heverlee, B 3001, Belgium
AU: Haile, M
EM: gualmitiku@yahoo.com
AF: Department of Land Resources Management and Environmental Protection, P.O.Box 231, Mekelle, ET, Ethiopia
AU: Grove, A D
EM: atdickgrove@hotmail.com
AF: Downing College, University of Cambridge, Cambridge, UK, United Kingdom
AB: Studies on the impact of environmental rehabilitation in semi-arid areas are often limited in scale, and do typically not include detailed bio-physical components (Rohde and Hilhorst, 2001). As a first in its kind, the present study makes a multi-scale assessment over a time span of 30 years of environmental rehabilitation in one of the world's most degraded areas: the Tigray highlands in Northern Ethiopia, where population has more than doubled over that period. Using methods related to geomorphology, hydrology, soil science and multi-temporal photomonitoring (Nyssen et al., 2007), we show that in Tigray, soil erosion rates have decreased, infiltration and spring discharge are enhanced, vegetation cover has increased and crop production improved compared to the prevailing situation a few decades ago. These impacts are quantified and substantiated by a comparison of current landscapes to the past situation by means of a comprehensive database of 30-year old photographs of representative landscapes covering the major agro-ecological zones of the region. This resilience will be discussed in the light of the socio-economic context in which it has taken place. Finally, the positive changes in ecosystem service supply that result from changing land cover and management are an issue of global concern. Our research demonstrates that the way is open to develop down-to-the-ground environmental indicators to gauge ‘Millennium Ecosystem Assessment' type approaches (Carpenter et al., 2006). Carpenter, S.R., DeFries, R., Dietz, T., Mooney, H.A., Polasky, S., Reid, W.V., Scholes, R.J., 2006. Millennium Ecosystem Assessment: research needs. Science 314: 257-258. Nyssen, J., Poesen, J., Descheemaeker, K., Nigussie Haregeweyn, Mitiku Haile, Moeyersons, J., Govers, G., Munro, R.N., Deckers, J., 2007. Reversing land degradation in marginal semi-arid areas: the case of Northern Ethiopia. Ecosystems, submitted. Rohde, R., Hilhorst, T., 2001. A profile of environmental change in the Lake Manyara Basin, Tanzania. Drylands Programme, IIED, Issue Paper 109, 31 p.
DE: 0481 Restoration
DE: 1815 Erosion
DE: 6304 Benefit-cost analysis
DE: 6334 Regional planning (1880)
DE: 9305 Africa
SC: Public Affairs [PA]
MN: 2007 Fall Meeting