A review of changes in rangeland vegetation and livestock populations for Northern Kenya
1999
M. Jacobs | L. Coppock
This review explores environmental change in northern and south-central Kenya, roughly covering three decades from the 1960s to the 1990s. The report answers three questions:has vegetation change occurred in these districts?if vegetation change has occurred, why and how has this happened?what are the trends for livestock populations?The article concludes that:rangeland sites have been fundamentally altered by woody encroachment over the past 40 years. This has resulted from concentration of grazing pressure that has occurred due to declines in the mobility of pastoral people and their herds. Human population growth, insecurity, inadequate distribution of key resources, and the lure of markets and public services are all implicated in this patternlivestock populations have not changed in numbers or species composition, as is evident from aeriel survey datathe lack of livestock number/species trend detection may be complicated by the imprecision of aerial survey data, the possibility that major changes in livestock populations occurred before the period of aerial survey, and/or the presence of non-forage factors such as epidemic disease and livestock raiding that can exert marked influences on population dynamics
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