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\hypersetup{pdftitle={Forest Assessment as a Pre"=requisite for a Rehabilitation Concept in the Forest"=savannah Transition Zone of Ghana},pdfauthor={Jörn Struwe, Jobst-Michael Schroeder},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Ghana, inventory results, rehabilitation, savannah forest, stand structure, stratification},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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\begin{center}
\Large{\textbf{Forest Assessment as a Pre"=requisite for a Rehabilitation Concept in the Forest"=savannah Transition Zone of Ghana\footnote{\textbf{Contact Address:} Jobst-Michael Schroeder, Johann Heinrich von Thünen-Institut, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute for World Forestry, Leuschnerstraße 91, 21031~Hamburg, Germany, \mbox{e-mail}: \email{jobst.schroeder@vti.bund.de}}\\[0.8ex]}}
\normalsize{\textsc{Jörn Struwe$^{1}$, Jobst-Michael Schroeder$^{2}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Fed. Research Centre for Forestry and Forest Products, Institute for Worldforestry, Germany}}}
\item[]{\small{\textit{$^{2}$Johann Heinrich von Thünen-Institut, Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute for World Forestry, Germany}}}
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\index[author]{Struwe, Jörn}
\index[author]{Schroeder, Jobst-Michael}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
A degraded site --- located in the forest"=savannah transition zone of the Ashanti Region, Ghana --- was stratified according to vegetation parameters on the basis of satellite images. Two vegetation strata were identified and classified as ``forest'' and ``savannah'' in accordance with FAO. The forest assessment --- following a systematic sampling design --- revealed an open and fire disturbed stand structure with an estimated average canopy cover of 21,\mbox{6\,\%} and a basal area per hectare of 9,89 m$^2$. The forest vegetation comprises of a single layer and features an average top height of 17,\mbox{7\,m}. Existing land"=use pressure is responsible for disturbances of the forest vegetation by traditional slash and burn"=practice. Furthermore, the forest vegetation is being cleared for charcoal production and is frequently being exploited by small"=game hunters. These activities are responsible for the occurrence of short"=interval ground fires of high spatial frequency, which impose a constraint for forest dynamics. Tree regeneration from seeds and coppice does still occur, but the forest vegetation is estimated to be in a regressive succession stage towards impoverished savannah vegetation. The tree species composition is floristically homogeneous. An average tree species number per sample plot of 10 $\pm$ 1 was observed resulting in a total number of 66 tree species --- which can be assigned to 48 genera and 25 families. The abundance of the tree species is distributed unevenly, since 23 tree species account for 87,4 percent of the surveyed trees. The majority of the tree species are characteristic for woodland savannah habitats. The vegetation type can be classified as derived Guinea savannah woodland. Two indigenous tree species --- Vitellaria paradoxa (Shea"=butter tree) and Pterocarpus erinaceus (Padouk, African rosewood) --- with high horizontal and vertical distributions have commercial value. 



According to the degree of disturbance and degeneration three strata for the rehabilitation of the site were identified: 1. conversion area without further silvicultural intervention, 2. enrichment area with adequate remaining forest cover that can be re"=developed into intact forests and 3. severely degraded forest for complete afforestation with site adopted plantation species. The rehabilitation success is seriously depending on reduced anthropogenic pressure.



}

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\noindent \textbf{Keywords:} Ghana, inventory results, rehabilitation, savannah forest, stand structure, stratification
\index[key]{Ghana}
\index[key]{Inventory results}
\index[key]{Rehabilitation}
\index[key]{Savanna forest}
\index[key]{Stand structure}
\index[key]{Stratification}
\end{document}