Abstract:
The current status of vegetation composition and condition of Ethiopian rangelands were highly
deteriorated due to factors such as bush encroachment, alien invasive plant species, recurrent
droughts, overgrazing, and expansion of cultivated land, which seems favoring unpalatable plant
species and drought tolerant thorny bushes. Therefore, this study was aimed to study the
vegetation structures and rangeland condition and their effects on livestock composition in
Mieso District of West Hararghe zone. A random sampling procedure was used to collect
vegetation data from 30 sample plots along four transect lines. Nested plot design was used a
size 20m x 20m for trees, 5m x 5m for shrubs and 1m x 1m for herbaceous plant species. The
density of plant species, DBH/DSH >2.5 cm and heights > 1m of woody species were collected.
Shannon - wiener diversity Index (H’), Basal area (BA), and evenness (E) were estimated. Visual
estimation of coverage/abundance values for woody and herbaceous species per plot was done.
In addition, key informant interview and focus group discussions were conducted to collect data
on herd dynamics and condition of the rangeland. The data were analyzed using SPSS version 21
software. In this study, a total of 97 species of vascular plants belonging to 39 families and 45
genera were recorded and identified. Trees, shrubs, herbs and grasses accounted for 23, 40, 18
and 16 species, respectively. The (H’) value of woody species was 2.4 with (E) value of 0.6, and
(H’) for herbaceous species was 1.9 with (E) value of 0.5 in all sites. Fabaceae is the dominant
Family followed by Poaceae, Euphorbiaceae and Tiliaceae which accounted for17.5%, 15.5%,
7.2%, and 6.2% of the plant species, respectively. Total BA of wood species was 4.14 m2
/ha. The
condition of the rangeland indicated that non-palatable woody and herbaceous plant species are
increasing and accounted for highest percentage (45.3% and 44.5% respectively) of the
vegetation cover. Most of the respondents involved in household survey and focus group
discussions believed that the rangeland vegetation composition had changed intensely in the past
10 or 20 years and resulted in herd composition dynamics of animals from grazers to browsers
(camels and small ruminants). Community survey indicated that, 75% of the respondents
mentioned that the status of their rangeland as fair (25.5) or poor (19.8) due to several
disturbances pressure resulting in low feed production with the increased unpalatable species.
The disturbances negatively diminished existing (native) species abundances, diversity and
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richness. Therefore, the rangeland of the study area requires immediate attention and
implementation of appropriate conservation and management strategies. As such, there is a need
for Integration of the traditional knowledge of the pastoralist community and their strong
participation in order to improve the rangeland condition in the study area.