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\hypersetup{pdftitle={Ecological Sustainability of Rice"=based Agroecosystems in Iran: a Case Study of Mazandaran Province},pdfauthor={Abdolmajid Mahdavi Damghani, Mina Mohajer},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Mechanisation, production, rice , socioeconomic, sustainability measurement},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{Ecological Sustainability of Rice"=based Agroecosystems in Iran: a Case Study of Mazandaran Province\footnote{\textbf{Contact Address:} Abdolmajid Mahdavi Damghani, Environmental Sciences Research Institute, Shahid Beheshti University, G.C., Evin street, 1983963113~Tehran, Iran, \mbox{e-mail}: \email{mmd323@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Abdolmajid Mahdavi Damghani$^{1}$, Mina Mohajer$^{2}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Environmental Sciences Research Institute, Shahid Beheshti University, G.C., Iran}}}
\item[]{\small{\textit{$^{2}$University of Tehran, Faculty of Law, Iran}}}
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\index[author]{Mahdavi Damghani, Abdolmajid}
\index[author]{Mohajer, Mina}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
In order to develop a sustainability index (SI) for quantifying the sustainability of rice"=based agroecosystems in Mazandaran, Northern Iran, a study was conducted in 2007 and 2008. Sixty nine indicators were selected to develop a sustainability index. The indicators classified in 9 groups as socioeconomic, crop production. Livestock production, agrochemical application, crop residue management, water and irrigation, tillage and machinery, agrobiodiversity and weed management indicators. Data were collected using 350 questionnaires. The weighting sum method was used to calculate the sustainability index. Each indicator had a score ranging from zero to a maximum value. The highest and lowest scores were for the most favourable and the worst conditions, respectively. The final value of 100 for the SI was the sum of all indicators' scores. Results showed that only 21.8 percent of farmers gained more than half of SI score and the mean SI score was 46.1 which indicate that these agroecosystems are not sustainable. Results of this study are in consistent with other reports in other regions of the country. Crop and livestock production, agrobiodiversity and tillage and mechanisation indicators had the lowest score (22, 32, and 39, respectively). The mean rice yield was \unitfrac[3100]{kg}{ha} and only \mbox{19\,\%} of farmers had yields more than \unitfrac[4000]{kg}{ha}. More than half of farmers applied 200--\unitfrac[400]{kg}{ha} chemical fertiliser which is a serious concern for environmental sustainability of these agroecosystems, according to low production level and high environmental vulnerability of these systems. The survey showed that any progress in farmers' education, economic viability, crop production management and accessibility to inputs and financial supports could improve overall sustainability of these agroecosystems substantially.}

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\noindent \textbf{Keywords:} Mechanisation, production, rice , socioeconomic, sustainability measurement
\index[key]{Mechanization}
\index[key]{Production}
\index[key]{Rice!}
\index[key]{Socioeconomic}
\index[key]{Sustainability measurement}
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