Effect of Different Moisture Harvesting Techniques on Seedling Survivals and Growth of Trees in Degraded Lands of Southern Tigray

Abstract

Tree planting on degraded lands play a key role in forest rehabilitation processes through afforestation and/or reforestation. Moisture harvesting structures (MHSs) has significant impact on seedling survivals at degraded lands. The objectives of this study were to investigate the impact of water harvesting techniques on seedling survival and growth performance of trees. Field experiments were conducted for two rainy seasons in southern Tigray, Atsela watershed. The experimental design followed was the split plot design. The MHSs as main plot used were eye-brow basins (EBs), micro trench (MTs), improved pit (IPs) and as control normal pit (NPs). The tree species grown as subplots were Eucalyptus camaldulensis, Grevillea robusta, Olea europaea and Cupressus lusitanica. The four tree species were planted by using seedlings. The tree survival rate, height, crown width (CW) and root collar diameter (RCD) of the four tree species were measured every six months after transplanting. The result shows that MHSs were significant in tree seedling height, CW and RCD but not in tree survival rate. Tree seedling height and CW grown in EBs were significantly higher than those grown in MTs, IPs and NP (P≤0.05). RCD of tree seedling was higher when grown in EBs than NP (control) (P≤0.05). The interaction of tree species seedlings and MHSs shows that those seedlings grown on MHSs were significantly thicker, taller and more survived than those grown on the NPs (control) (P≤0.05). So based on the experiments, it is concluded that MHSs particularly the eyebrow basin was considered as the most appropriate planting pit. Therefore, further demonstration of eyebrow basin tree planting should be carried out.