Selection of Different Trees/Shrubs Species for Rehabilitation of Degraded Lands in Wag-Lasta Area, Northeastern Ethiopia

Abstract

Due to human and livestock population pressure, land degradation is the main problem in many part of Ethiopia. To avert the situation, tree and shrub species selection on degraded lands are valuable tool for ecological restoration. Therefore, the aim of this study was to select the best performing tree and shrub species in three agro-ecological zones of Waglasta area, Ethiopia. The experiment was conducted in randomized block design with three replications in highland, mid altitude, and lowland sites. For total experimental setup 21 (seven for lowland, eight for mid altitude and six for highland) tree and shrub species were used. Growth and survival rate data were collected every 3 months interval for one year and every 6 months up to the end of the experiment. The result indicated that L. pallid (2.52 ± 0.19 m) at lowland site, Acacia senegal (1.32±0.23 m) at mid altitude and Acacia decurrens (4.0 ± 0.46 m) at highland site had shown better performance in height. Similarly, Moringa stenopetala at lowland, Jatropha carcus at mid altitude and Acacia saligna at highland site had shown 8.63 ± 2.37 cm, 3.1 ± 0.2 cm and 7.06 ± 0.75 cm performance in root collar diameter, respectively. However, the survival rate was higher for A. senegal (43 ± 7%) and M. stenoptella (44 ± 17%) at lowland site, A. senegal (98 ± 2%) at mid altitude and A. saligna (63.9 ± 20.0%) at highland site. Therefore, to restore degraded lands and to support the on-going land rehabilitation programs of Wag-lasta area, we recommend A. senegal and M. stenoptella for lowland site, A. senegal for mid altitude areas and A. saligna for highland site of Lalibela, Abergele and Sekota and similar agro-climatic zones. However, additional studies regarding soil nutrient dynamics, fostering effect and tree nursing should be integrated to develop sound ecological restoration strategies in the growth corridor as well as in the region.