Influence of Aspect and Elevational Gradients on The Regeneration of Festuca Macrophylla and Helicrysum Spelindidum Plant Species in GCCA, Central Highlands of Ethiopia

Authors: Chengere SA*, Dullo BW, Nemomissa S and Gebrehiwot K

DOI: 10.23880/jenr-16000354

Volume 7, Issue 4

Abstract

Natural regeneration is an important process that ensures the flow genes and thus preserves the diversity of life in ecosystems. However, natural regeneration is constrained by many factors including biotic, climatic and edaphic factors. The aim of this work was to assess the effects of aspect and elevational gradient on the natural regeneration potential of two competing species in Guassa Community Conservation Area in North Central Ethiopian highlands. We stratified our study area into eight blocks based on aspect and elevational gradient and conducted shrub removal experiment on 160 plots (5m x 5m). From these plots, we conducted vegetation survey following the modified Braun-Blanquette methods every three months. We used two elevational (<3350 m/lower and >3350 m/upper elevation) and four aspect categories (northeast, northwest, southwest and southeast) to compare the seeding density of the target species and species composition studies. On these plots, all vascular plants were recorded and the data was analyzed by two-way ANOVA using SAS statistical software version 9.0.1. In addition, we used LSD test for mean separation test. We computed the similarities in composition, density, abundance and species similarity between soil seedbank and the aboveground vegetation. Results showed that a total of 31 species, representing 27 genera and 16 families were recorded. The families with the highest number of species were Asteraceae (18 species, 22.5%), Fabaceae (3 species, 10%), and Poaceae (3 species, 10%). Of the total families, the dicots constituted 87.5% and monocots 12.5%. Species abundance was negatively correlated with elevation, with fewer species occurring at higher elevation. Meanwhile, species abundance was positively correlated with both northwest and northeast aspect. Treatments done during the study also highly influenced the recovery of vegetation species. High species similarity was also observed between below and aboveground vegetation.

Keywords: Elevation Gradient; Guassa Community Conservation Area; Regeneration Potential, Similarity; Species Recovery

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