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\hypersetup{pdftitle={Water Quality Evaluation of Ogun River and its Impact on Agriculture and Environment},pdfauthor={Opeyemi Anthony Amusan, Ayorinde Olufayo, Philip Oguntunde},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Irrigated agriculture, Physico–chemical analysis, River Basin, Surface water quality, Water treatment},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{Water Quality Evaluation of Ogun River and its Impact on Agriculture and Environment\footnote{\textbf{Contact Address:} Opeyemi Anthony Amusan, University of Bonn, Agricultural Science \& Resource Management in the Tropics and Subtropics (ARTS), Nussallee 1, 53115~Bonn, Germany, \mbox{e-mail}: \email{amusanopeyemi@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Opeyemi Anthony Amusan$^{1}$, Ayorinde Olufayo$^{2}$, Philip Oguntunde$^{2}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Bonn, Agricultural Science \& Resource Management in the Tropics and Subtropics (ARTS), Germany}}}
\item[]{\small{\textit{$^{2}$Federal University of Technology, Agricultural Engineering, Nigeria}}}
\end{itemize*}
\index[author]{Amusan, Opeyemi Anthony}
\index[author]{Olufayo, Ayorinde}
\index[author]{Oguntunde, Philip}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Surface water qualities of River Ogun, a major river draining the Ogun "= Osun River Basin Development Authority (OORBDA) area of South Western Nigeria, were studied to evaluate their impact on agriculture and the environment. South"=western Nigeria occupies about 30 percent of Nigeria and has an estimated population of about 30 million. Over 50 percent of the area is categorised as rural areas of which about 70 percent of the people depend on the River for their livelihood.  



Water and soil samples were collected from the river and nearby irrigated farms at dams within the river catchment areas such as Ikere (Upper Ogun), Sepeteri (Upper Ogun), Iseyin (Middle Ogun), Oyan (Middle Ogun), Mokoloki (Lower Ogun) and Ito Ikin (Lower Ogun) monitoring the river flow from Upper Ogun to Lower Ogun. They were analysed using standard methods, and physico"=chemical parameters values obtained were compare with known and accepted standards.



The range of values for Biological Oxygen Demand (BOD), Total Suspended Solids (TSS), Dissolved Oxygen (DO), and Total Coliform Count (TCC) obtained were 975 to \unitfrac[1580]{mg}{l}, 40 to \unitfrac[120]{mg}{l}, 180 to \unitfrac[273]{mg}{l} and 1000 to \unitfrac[2000]{cfum}{l}, respectively. When compared with standards, these results show that the river is highly polluted and hence unfit for domestic water supply, stock watering, aquaculture and recreational activities unless appropriate and adequate treatments are employed. However, the values of Acidity and Alkalinity obtained were within acceptable range.



The water is suitable for irrigated agriculture provided the gravity system of irrigation is intended. Some amount of filtering is recommended if the sprinkler system is to be used in all the locations.}

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\noindent \textbf{Keywords:} Irrigated agriculture, Physico"=chemical analysis, River Basin, Surface water quality, Water treatment
\index[key]{Irrigated agriculture}
\index[key]{Physico"=chemical analysis}
\index[key]{River Basin}
\index[key]{Surface water quality}
\index[key]{Water!treatment}
\end{document}