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\hypersetup{pdftitle={Economic Valuation of Surface Runoff Reduction in Forest Ecosystems: Case Study of Zagros Forests, Iran},pdfauthor={Zahra Mashayekhi, Mostafa Panahi, Mahmoud Karami},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Bazoft River watershed, curve number, economic valuation, replacement cost, runoff},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{Economic Valuation of Surface Runoff Reduction in Forest Ecosystems: Case Study of Zagros Forests, Iran\footnote{\textbf{Contact Address:} Zahra Mashayekhi, Ghods-niroo Engineering Company, Ostad Motahhari, Tehran, Iran, \mbox{e-mail}: \email{mashayekhi.zahra@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Zahra Mashayekhi$^{1}$, Mostafa Panahi$^{2}$, Mahmoud Karami$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Ghods-niroo Engineering Company, Iran}}}
\item[]{\small{\textit{$^{2}$Islamic Azad University, }}}
\item[]{\small{\textit{$^{3}$University of Tehran, Natural Resources Faculty, }}}
\end{itemize*}
\index[author]{Mashayekhi, Zahra}
\index[author]{Panahi, Mostafa}
\index[author]{Karami, Mahmoud}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Forests are ecosystems, which besides producing timber, seeds, fodder and a few other marketable non"=wood products, also produce ecosystem services that provide benefits to human society in general and the economic sub"=system in particular. However, these services are not recognised fully by human societies. The economic valuation of ecosystem services has become one of the most significant and fastest evolving research areas in environmental and ecological economics. In this paper, the economic value of water conservation by Bazoft watershed located in Zagros forests in western Iran was estimated, using simulation models and Geographic Information System (GIS) as a tool for analysing the effects of ecological factors on ecosystem services. Rainfall"=runoff simulation was carried out by using Curve Number (CN) method in HEC-HMS model. The model requires the inputs of land cover, soil maps, and short term rainfall and discharge data. The efficiency of simulated model was increased using observed data and doing calibration stages. Then the role of forest on water retention and surface runoff reduction by devising four hypothetical scenarios and then the effects of land use changes associated with these scenarios on rainfall"=runoff behaviour of the region were determined. The results showed that under the case of scenario one which assumes that the entire of watershed area is covered by forests, total outflow would be in the minimum amount and rainfall initial loss will increase. Forest hydrological services related to water retention was economically assessed using Replacement Cost Method. Valuation results showed that each hectare of Bazoft forests can store 84.8 m$^{3}$ water with 0.5 US\$/ m$^{3}$ annual value. So the water retention value of each hectare of these forests will be 43US\$. This could have positive economic consequences for the region and would help decision"=makers in selecting appropriate and economically feasible development strategies. The majority of rural settlements in Bazoft watershed are low income communities dependent upon the forest lands for their subsistence. Moreover, these results can become useful tools for implementing green policy initiatives and sound conservation practices, such as market mechanisms for payment of specific hydrological environmental services by hydroelectric firms and large"=scale agricultural industries.







}

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\noindent \textbf{Keywords:} Bazoft River watershed, curve number, economic valuation, replacement cost, runoff
\index[key]{Bazoft River watershed}
\index[key]{Curve Number}
\index[key]{Economic!valuation}
\index[key]{Replacement Cost}
\index[key]{Runoff}
\end{document}