Elevational changes in vascular plants richness, diversity, and distribution pattern in Abune Yosef mountain range, Northern Ethiopia

Abstract

The aim of this research is to investigate the patterns of vascular plant species richness, diversity, and distribution along an elevation gradient in the Abune Yosef mountain range, Ethiopia. Preferential systematic sampling was employed to collect vegetation and environmental data along the elevation gradient. We found that plant species richness declines monotonically from low to high elevations. Specifically, vascular plant species richness and diversity were lower in the Afroalpine grassland (high elevation) than in the Dry evergreen Afromontane forest and Ericaceous forest (low elevations). In contrast, endemic vascular plant richness was significantly higher in the Afroalpine grassland than in the Dry evergreen Afromontane forest and Ericaceous forest. Elevation showed a significant impact on the richness, diversity, and endemism of vascular plants. According to Sørensen's coefficient, the similarity between Dry evergreen Afromontane forest and Ericaceous forest vegetation types is higher (32%) than the similarity between Ericaceous forest and Afroalpine grassland (18%). Only 5% similarity was recorded between the Dry evergreen Afromontane forest and Afroalpine grassland. Growth forms showed different elevational richness patterns. Trees and liana increased monotonically up to 3300 m. Shrub and herb richness patterns followed a hump-shaped and inverted hump-shaped pattern along the elevation gradient. The elevation patterns of vascular plant species richness, diversity, and growth form in the present study may be attributed to differences in management intensity, spatial heterogeneity, microclimatic variations, and anthropogenic disturbances.

Ecological and floristic study of Hirmi woodland vegetation in Tigray Region, Northern Ethiopia

“…Patterns of species community are associated with environmental factors including climate, topography, and soil as well as anthropogenic and livestock disturbances (Whittaker et al 2003). Ecological studies conducted in Ethiopia by Woldu et al (1989), Friis (1992), Bekele (1994), Aynekulu (2011), Kelbessa and Girma (2011) and Gebrehiwot et al (2019) reported the importance of environmental variables (altitude, slope, landscape, disturbances, and soil physical and chemical properties) in shaping plant communities. CCA analysis result showed that environmental variables including altitude, slope, silt, sand, soil organic matter, total nitrogen, and disturbances are associated with species compositions of plant communities in the Hirmi woodland.…”

“…This community was less disturbed and had high species richness due to the fact that plots of the community were taken in sites far from the edge effect and sloping areas. Species found on strong slopes are less disturbed and would be rich in species composition (Tilahun et al 2011;Gebrehiwot et al 2019).…”

Ecological and Floristic Study of Hirmi Forest, Tigray Region, Northern Ethiopia

“…Patterns of species community is associated with environmental factors such as climate, topography, and soil as well as anthropogenic and livestock disturbances (Whittaker et al 2003). Ecological study conducted in Ethiopia by Woldu et al (1989), Friis (1992), Bekele (1994), Aynekulu (2011), Kelbessa and Girma (2011) and Gebrehiwot et al (2019) reported importance of environmental variables (altitude, slope, landscape, disturbances, and soil physical and chemical properties) in separation of forest communities.…”

“…Soils having high organic matter and moisture holding capacity of the silt loam of soil are suitable for species growth and diversity (Brown 2003;O'Geen 2006). Furtherly, species found in strong slope are less disturbed and would be rich in species composition (Tilahun et al 2011;Gebrehiwot et al, 2019). The longest arrow of altitude in the ordination axis was positively correlated with community type four (Euclea racemosa -Acacia abyssinica) than the other community types.…”

Distributional Patterns of Aquatic Empididae (Diptera) along an Elevational Diversity Gradient in a Low Mountain Range: An Example from Central Europe

“…Many ecological studies reveal two main patterns of relationships between species richness and altitude: a monotonic decline in species richness with increasing elevation, and a hump-shaped relationship, with mid-elevation peaks in species richness [ 1 ]. Both models are well documented by studies focused on plants and vertebrates, especially birds and mammals [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Recent studies show that the second pattern seems to be more common [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ].…”