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\hypersetup{pdftitle={Assessment of the Role of Forests as a Natural Rangeland: Elrawashda Forest as a Natural Rangeland},pdfauthor={Yousif Yagoub, Mudawi Elobeid, Awad Abusuwar},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Deforestation, Elrawashda forest reserve, rangelands, overgrazing, regeneration},pdfpagemode=None,colorlinks=true}
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\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 14-16, 2010, Zurich}}\\[1ex] \Large{``World Food System  ---\\A Contribution from Europe''\\[2ex]}}
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\Large{\textbf{Assessment of the Role of Forests as a Natural Rangeland: Elrawashda Forest as a Natural Rangeland\footnote{\textbf{Contact Address:} Yousif Yagoub, University of Khartoum, Department of Forest Conservation and Protection, Elazhari Street, 13314~Khartoum North, Shambat, Sudan, \mbox{e-mail}: \email{yousif.yagoub@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Yousif Yagoub$^{1}$, Mudawi Elobeid$^{2}$, Awad Abusuwar$^{3}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Khartoum, Department of Forest Conservation and Protection, Sudan}}}
\item[]{\small{\textit{$^{2}$University of Khartoum, Department of Silviculture, Sudan}}}
\item[]{\small{\textit{$^{3}$University of Khartoum, Department of Agronomy, Sudan}}}
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\index[author]{Yagoub, Yousif}
\index[author]{Elobeid, Mudawi}
\index[author]{Abusuwar, Awad}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Natural forest reserves play a role as natural rangelands in tropical countries of which Sudan is no exception. Frequent drought cycles¸ fires and overgrazing contributed to deterioration of forests. Overgrazing is particular constitutes a real threat to these forests where animals populations outweigh by far the carrying capacity of forest resulting in retrogression and disappearance of some palatable species and appearance of new unpalatable ones. This necessitates conservation and rehabilitation of forest in the absence of proper protection and management. In this study Elrawashda forest (Gadaref State, Sudan) was chosen as a model natural forest reserve and the main goal was to assess the role of natural forest reserves as natural rangelands with special emphasis on the impact of grazing in terms of deforestation and invasion of unpalatable species. To address this goal¸ a field experiment in 20 fed affected by heavy grazing during the period 2008--2009 was designed consisting  of 4 different treatments (seeds broadcasting, seeds sowing after disc ploughing, seeds sowing using water harvesting technique and the control (no seeding)). These regeneration methods were analysed to screen for the best method as a means for regeneration. This analysis was supported by primary data (social survey as face"=to-face interviews with pastoralists and local communities in the study area) as well as secondary data from the records of Range and Pasture Administration and Forest National Corporation in Sudan. Results showed distinct ecological changes in the study area as indicated by deterioration of the rangelands and retrogression where some palatable weed species disappeared and replaced by other unpalatable species due to open overgrazing, illegal tree felling by the local people and expansion in the rain"=fed mechanised agricultural schemes. Significant differences were observed among the treatments and the best regeneration\% was found under disc ploughing compared to other treatments, followed by seed sowing under water harvesting technique and seeds broadcasting relative to the control. In conclusion, deterioration of natural rangelands in forest reserve was strongly associated with existence of livestock in forest area for a long period of time. Further studies were suggested for rehabilitation of these forests. 







}

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\noindent \textbf{Keywords:} Deforestation, Elrawashda forest reserve, rangelands, overgrazing, regeneration
\index[key]{Deforestation}
\index[key]{Elrawashda forest reserve}
\index[key]{Rangelands}
\index[key]{Overgrazing}
\index[key]{Regeneration}
\end{document}