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\hypersetup{pdftitle={Effect of Land Use Change on Properties and Clay Mineralogy of Forest Soils Developed in Iran},pdfauthor={Najmeh Rezaee, Mohammadhasan Roozitalab},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Forest soils, land use change, soils of Iran, tea cultivation},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{Effect of Land Use Change on Properties and Clay Mineralogy of Forest Soils Developed in Iran\footnote{\textbf{Contact Address:} Najmeh Rezaee, University of Guilan, Department of Soil Science, Tehran, Iran, \mbox{e-mail}: \email{najmehrezaee@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Najmeh Rezaee$^{1}$, Mohammadhasan Roozitalab$^{2}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Guilan, Department of Soil Science, Iran}}}
\item[]{\small{\textit{$^{2}$International Center for Agricultural Research in the Dry Areas (ICARDA), Iran Office, Iran}}}
\end{itemize*}
\index[author]{Rezaee, Najmeh}
\index[author]{Roozitalab, Mohammadhasan}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Land use and land cover changes significantly influence the soil properties and modify soil forming processes. land use changes, such as conversion of forest to cultivated land, can drastically affect the soil environment, which in turn markedly influence soils and soil development. All of the tea plantations in Iran are concentrated in the Caspian Sea region on soils previously developed under deciduous natural forest. This research conducted to study the effect of land use change (from forest to tea) on selected physico"=chemical and mineralogical properties of soils formed on granitic formation under humid climate and mountainous landforms in Northern Iran. After field investigation three transects facing west to northwest in both tea plantation and the nearby natural forest were selected. A total of 18 soil profiles formed on different physiographic positions i.e. summit, shoulder and foot slope were studied and morphological features of each horizon were described. Soil samples taken from each horizon were analyzed. A two factorial complete randomised design was used to take soil samples from surface horizons of soils in each transect. The result showed that after changing forest to tea cultivation soils at $p < 0.01$ significant level, had lower pH, cation exchange capacity, and amounts of clay content as well as the amount of organic carbon content of the soils were decreased, but bulk density were increased compared to soils under natural forest. X-ray diffractograms of clay fractions showed vermiculite and vermiculite"=illite mixed layers. Hydroxy interlayered were the major clay minerals. Soils under tea cultivation possessed higly developed and more prominent argillic horizons and contained more clay fraction content in the lower horizons in all physiographic positions.}

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\noindent \textbf{Keywords:} Forest soils, land use change, soils of Iran, tea cultivation
\index[key]{Forest!soils}
\index[key]{Land!use change}
\index[key]{Soils of Iran}
\index[key]{Tea cultivation}
\end{document}