Abstract:
The traditional and uncontrolled grazing system in the communal grazing lands of the central
Ethiopian highlands, had resulted in severe soil degradation. This study was intended to
determine the effects of grazing exclusion and soil and water conservation(SWC)measures on
grass biomass production and selected soil properties and to assess the strategies and
perceptions of farmer’s towards grazing and its management. Six grazing exclusion (GE) fences
and adjacent six free grazing (FG) plots, each 2X 2m, were established at Gedda watershed, of
which three of them were in treated lands with SWC measures while the rest three were in areas
where there was no SWC treatment. A total of 192 aboveground biomass (AGB) samples were
collected at four sampling periods.The soil samples were collected in two of the randomly
selected quadrants from both the exclosures and adjacent FG plots within two soil depths, 0-15
and 15- 30 cm.The analysis result revealed that bulk density, sand, silt, Ca2+, Mg2+, Na+
, SOM,
SOC, TN, available Pand AGB were significantly affected as a result of grazing exclusions while
EC, pH, CEC, K
+
and C: N showed no significant difference. SWC greatly impacted different soil
parameters, i.e. lower bulk density and sand percentage, higher clay, SOM and SOC, illustrating
the effectiveness of employing SWC measures together with other management strategies so as to
prevent soil erosion and degradation in grazing lands. Thus grazing exclusion and SWC should
be adopted jointly and soil conditions prior to exclusions should be considered for better
outcomes.
