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\hypersetup{pdftitle={Biological Evaluation and Survey of Pollutant Sources of Cheshmeali River at Semnan Providence of Iran},pdfauthor={Kamran Rezai Tavabe, Gholamreza Rafiee, Leila Taheri Azad},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Benthose, Biological index, cheshmeh-ali River},pdfpagemode=None,colorlinks=true}
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\begin{document}
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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{Biological Evaluation and Survey of Pollutant Sources of Cheshmeali River at Semnan Providence of Iran\footnote{\textbf{Contact Address:} Kamran Rezai Tavabe, University of Tehran, Department of Fishery, Tehran, Iran, \mbox{e-mail}: \email{krtavabe@ut.ac.ir}}\\[0.8ex]}}
\normalsize{\textsc{Kamran Rezai Tavabe$^{1}$, Gholamreza Rafiee$^{1}$, Leila Taheri Azad$^{2}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Tehran, Department of Fishery, Iran}}}
\item[]{\small{\textit{$^{2}$Tarbiyat Modares University, Department of Environmental Science, Iran}}}
\end{itemize*}
\index[author]{Rezai Tavabe, Kamran}
\index[author]{Rafiee, Gholamreza}
\index[author]{Taheri Azad, Leila}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Fresh Water Rivers are one of the most important aquatic ecosystems in arid and semi"=arid regions. These rivers are typical ecosystem and important source for drinking water. Cheshmehali River is one of these rivers in Semnan province that during previous years has been threatened by droughts and anthropogenic pollutions. Pollution has the potential to affect the biological integrity of aquatic systems, decreases the quality of waters and may directly affect human health. Monitoring programs for freshwater ecosystems have increasingly used benthic invertebrate communities as an indicator of environmental pollution to complement chemical, microbiological and toxicity testing of surface waters. The purpose of this study is to consider benthose biodiversity of the river; for this purpose, limnological and biological studies of the river were carried out seasonally in 2008. At this study, five sampling stations were determined based on limnological standard method along the river; afterwards sampling of invertebrates (Biological Index) were performed seasonally during this time zone. The results of this study showed that the forth station is free of pollution and has highest biodiversity while the second station is the most polluted region at the river because the first station has no pollutant resource but the first station directly receives wastewater of rainbow trout fish culture centre. The insect species from Hydropsyche genus in forth station and Simolium genus in first, second, third and fifth stations were observed. Insect species such as Rhitrogena sp., Liponeura sp. and Ecdyonurus sp. relate to free organic pollution area that in studied sampling stations were observed in forth station only. }

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\end{abstract}
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\noindent \textbf{Keywords:} Benthose, Biological index, cheshmeh"=ali River
\index[key]{Benthose}
\index[key]{Biological index}
\index[key]{Cheshmeh"=ali River}
\end{document}