A Review of Bush Encroachment in Namibia: From a Problem to an Opportunity?

Journal of Rangeland Science

مقاله 4، دوره 10، شماره 3، مهر 2020، صفحه 251-266   

نوع مقاله: Review and Full Length Article

نویسندگان

Rosemary Shikangalah^{* 1}؛ Benjamin Mapani²

¹Department of Geography, History and Environmental Studies, University of Namibia

²Department of Mining and Process Engineering, Namibia University of Science and Technology, Windhoek, Namibia

چکیده

Bush encroachment leads to land degradation in semiarid to arid regions. Over 45 million hectares of agricultural land in Namibia are affected. This is worrisome as nearly 70% of the Namibian population depends on agricultural activities and the beef industry is the mainstay of the farming communities. This study employed secondary data sources to provide a review of the problems and benefits of bush encroachment in Namibia. The phenomenon has led to decreased biodiversity, degradation of the functions and structures of ecological ecosystems, lowering the grasslands’ carrying capacity, displacement of wildlife, as well as impacting groundwater recharge. Encroachers include species such as Senegalia erubescens, Senegalia fleckii, Vachellia nilotica, Vachellia luederitzii, Vachellia reficiens, Colophospermum mopane, Rhigozum trichotomum, Terminalia prunioides, Terminalia sericea, Senegalia mellifera and Dichrostachys cinerea. In 2018, the beef industry made at least US$ 184 million dollars. This amount could have been more, if the carrying capacity of the grazing lands was not reduced. On the other hand, the encroachers offer extra income from de-bushed wood material, including income from charcoal industry, which currently flourishing. Namibia is presently one of the main charcoal exporters and made close to US$34 million during the year 2018, putting the country on a first 1^st position in Africa and 11^th position worldwide. This brings a dilemma in managing the encroachers, as to whether to eliminate them and improve the grasslands or to allow them to grow for other benefits. The study concludes that while trying to improve the ecosystems by de-bushing, managing de-bushing needs to be sustainable. There is also a need for research to largely focus on evaluating the trade-offs between the problem and opportunities.

کلیدواژه‌ها

Bush encroachment؛ problems؛ de-bushing benefits؛ value chains؛ Namibia

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