A Review on Bush Encroachment Effect on Cattle Rearing in Rangelands
محورهای موضوعی : Forage QualityShimels Ali 1 , Getachew Muche 2
1 - Department of Biology, College of Natural and Computational Sciences, Dire-Dawa University, Dire-Dawa,Ethiopia
2 - Ethiopian Biodiversity Institute, Wildlife studies, Mekele center, Mekele, Ethiopia
کلید واژه: Biodiversity, Rangeland, Pastoralists, Bush encroachment, Cattle raring, Palatable grasses, Woody species,
چکیده مقاله :
Bush encroachment is an increase in woody plant density typically resulting in impenetrable thickets, suppressing palatable grasses and herbs. Moreover, bush encroachment is a globally observed phenomenon. Besides, increasing the density of unpalatable shrubs and trees has reduced the carrying capacity and threatens the sustainability of grazing animal production, especially in arid and semi-arid grasslands and savannas around the world. Bush encroachment is a serious environmental and economic problem. In addition, biodiversity, wildlife habitat and nutrient cycling (rates, magnitude, seasonability and spatially patterns) are affected by these changes in vegetation. Although the increases in woody plant abundance have widely noted, such elements as rates, dynamics, spatial patterns and approximation have not been well documented. However, land use practices such as increased grazing pressure and decreased fire frequency have been associated with shifts from grass to woody plant domination. The pastoralists have been using the traditional grazing management in order to cope up with the relatively arid conditions of the environment, prevent from overgrazing and ensure the sustainability of resource base.
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