The effect of shade levels on the survival and growth of planted trees in dry afromontane forest: Implications for restoration success

摘要

Understanding the growth response of different species to canopy gaps will lead to a further perception of species differentiation. Many experimental studies have shown that seedlings can benefit from neighboring plants due to reduced abiotic stress, increased availability of nutrients or reduced herbivorous pressure. Accordingly, this study assessed the differences in survival, root collar diameter (RCD), and height (H) growth of planted seedlings in Desa'a dry afromontane forest, Northern Ethiopia. Seedlings were planted in a random block design with three treatments: canopy cover, artificial shading, and tree species. The canopy cover density had three treatment levels (Open (37%), Medium (51%), and Dense (67%)), artificial shading had two levels (with or without), and tree species had three levels (Dodonea angustifolia Vahl., Olea europaea sub spp. cuspidate, and Juniperus procera Hochst). This study concluded that protection has contributed to the success of the early establishment of seedlings so it should be taken as a prerequisite in enrichment planting programs until seedlings are no more endangered for their establishment. Also, the success of an early seedling establishment with artificial shading and nursery trees implies the need to establish the optimal shading range, which is an important consideration for the success of enrichment activities.