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Journal of Arid Land  2018, Vol. 10 Issue (1): 1-11    DOI: 10.1007/s40333-017-0036-0
Orginal Article     
Determinants and rates of land degradation: Application of stationary time-series model to data from a semi-arid environment in Kenya
Z MGANGA Kevin1,*(), M NYARIKI Dickson2,3, K R MUSIMBA Nashon1, A AMWATA Dorothy1
1 Department of Range and Wildlife Sciences, South Eastern Kenya University, 170-90200 Kitui, Kenya
2 Department of Agricultural Economics and Agribusiness, South Eastern Kenya University, 170-90200 Kitui, Kenya
3 School of Business and Economics, Murangá University of Technology, 75-10200 Murangá, Kenya;
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Abstract  

The causes of land degradation in the African drylands have been shown to vary. Some researchers consider climate to be the major contributor to degradation, with anthropogenic factors playing a minor role. Others reverse the significance of these two factors. A third group attributes land degradation to climate and anthropogenic factors equally. This study was undertaken to establish the factors influencing land degradation in a semi-arid environment in southeastern Kenya and the rate of change in vegetation types for a period of 35 years (1973-2007). The reduction in grassland cover was used as an indicator of land degradation. Causes of land degradation were determined by a multiple regression analysis. A log-linear regression analysis was used to establish the rate of vegetation change. The multiple and log-linear regression analyses showed: (1) woody vegetation, livestock population and cultivated area to be the main contributors of reduction in grassland cover in the area, and (2) an increase in undesirable woody species, livestock population and cultivated area had a significant (P<0.05) negative effect on grassland vegetation. Increased human population, low amounts of rainfall and drought showed no significant negative effect on grassland vegetation cover. In conclusion, human and livestock population growth and increased agricultural land have contributed to intensive crop cultivation and overgrazing in the semi-arid lands. This overuse of the semi-arid rangelands has worsened the deterioration of the natural grassland vegetation.



Key wordsregression analysis      land degradation      grassland cover      semi-arid Kenya      Sub-Saharan Africa     
Received: 28 January 2017      Published: 10 February 2018
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Cite this article:

Z MGANGA Kevin, M NYARIKI Dickson, K R MUSIMBA Nashon, A AMWATA Dorothy. Determinants and rates of land degradation: Application of stationary time-series model to data from a semi-arid environment in Kenya. Journal of Arid Land, 2018, 10(1): 1-11.

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http://jal.xjegi.com/10.1007/s40333-017-0036-0     OR     http://jal.xjegi.com/Y2018/V10/I1/1

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