XVIIth AETFAT Congress Taxonomy and Ecology of African Plants for their Conservation and Sustainable Use Book of Abstracts pages:70-71
AETFAT Congress edition:17 location:Addis Ababa date:21-26 September 2003
In the Northern-Ethiopian highlands, deforestation and subsequent soil erosion have led to serious environmental degradation. High fuel wood demand and livestock grazing pressure continue causing further deterioration of the scarce forest resources. Low-cost forest rehabilitation is one of many essential factors needed to attain sustainable livelihood in the region. Seed dispersal from isolated forest fragments into adjacent degraded lands can improve natural forest regeneration, but basic knowledge on indigenous forest ecology is lacking. This paper classifies forest remnants in Central-Tigray and evaluates their potential as seed sources.
Environmental and floristic data were assessed in 10 forest remnants and analysed with multivariate techniques (TWINSPAN, DCCA). Five forest types with distinct tree associations were identified. Soil available phosphorus, stoniness, water and topographic position determine forest typology. Fertile, deep valley soils support Montane Evergreen Riparian High Forest and its degraded phase. Steep Hillside Woodland dominates stony slopes with inferior growing conditions. Shallow, nutrient-poor plateau soils support Degraded Montane Savanna Woodland and river banks Degraded Riparian Scrub. Forest remnants are relatively vital. High abundance of wind and animal dispersed trees enables direct forest expansion if the surrounding lands are properly managed. Establishment of closed areas (grazing exclosures) should therefore be concentrated around the forest remnants.