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\hypersetup{pdftitle={Evaluating the Best Size of Forest Treefall Gap to Optimise Production of Natural Raspberry (Rubus hyrcanus) in Northern Hardwood Forests of Iran},pdfauthor={Seyyed Mohammad Waez Mousavi, Hashem Habashi, Ardeshir Abbasi},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Forest gap, forests of Iran, gap area, raspberry},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{Evaluating the Best Size of Forest Treefall Gap to Optimise Production of Natural Raspberry (Rubus hyrcanus) in Northern Hardwood Forests of Iran\footnote{\textbf{Contact Address:} Seyyed Mohammad Waez Mousavi, Gorgan University of Agricultural Sciences and Natural Resources, Forestry and Wood Technology Faculty, Forest Ecology, Shahid Beheshti Gorgan University of Agricultural Sciences and Natural Resources, 49165-386~Gorgan, Iran, \mbox{e-mail}: \email{smwaez@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Seyyed Mohammad Waez Mousavi$^{1}$, Hashem Habashi$^{2}$, Ardeshir Abbasi$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Gorgan University of Agricultural Sciences and Natural Resources, Forestry and Wood Technology Faculty, Forest Ecology, Iran}}}
\item[]{\small{\textit{$^{2}$Gorgan University of Agriculture and Natural Resources, Forestry and Wood Technology Faculty, Forest Ecology, Iran}}}
\item[]{\small{\textit{$^{3}$Gorgan University of Agricultural Sciences and Natural Resources, Forestry and Wood Technology Faculty,, Forest Ecology, }}}
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\index[author]{Waez Mousavi, Seyyed Mohammad}
\index[author]{Habashi, Hashem}
\index[author]{Abbasi, Ardeshir}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Forest gap is a space in canopy cover which happens due to natural or unnatural falling of a tree and causes some changes in environmental conditions of forest. Iranian north forests (namely Hyrcanian forests) are deciduous temperate forests located in the north of Iran on the northern slopes of the Alborz Mountain in the south of the Caspian Sea. Ecologically as well as economically these forests play an important role in the region, they are an important source of some forest crops such as natural raspberry (Rubus hyrcanus). Raspberry has a prominent position in local economy and causes a considerable yearly income for rural and forest adjacent resident and private woodland owners. In this manner by cutting one or more trees a forest gap will be created in which raspberry will naturally appear. Since raspberry is a light demanding species therefore its abundance in gaps increase due to gap area expansion but creating more spacious gaps means more tree cutting and less stable ecosystem. This study aimed to investigate the effect of gap area on raspberry abundance and to find an optimal point between gap area and raspberry abundance therefore 40 gaps with different sizes (from about 100 to 1200 m$^{2}$) were selected in a natural wood land. In each gap the area and the abundance of raspberry were recorded. Regression analysis was used to find the effect of gap area on raspberry abundance. Results showed that increasing in gap size increases raspberry abundance (R=0.64). Regarding regression curve this increase significantly continues up to the gap area of about 400 m$^{2}$ but thereafter the increase is insignificant. Therefore it is strongly recommended to create gaps with the area of about 400 m$^{2}$, because smaller gaps haven't enough raspberry and bigger gaps mean more forest degradation without a significant increase in raspberry abundance. }

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\noindent \textbf{Keywords:} Forest gap, forests of Iran, gap area, raspberry
\index[key]{Forest!gap}
\index[key]{Forests of Iran}
\index[key]{Gap area}
\index[key]{Raspberry}
\end{document}