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\hypersetup{pdftitle={Exploring the Diversity of Urban and Peri"=urban Agricultural Systems in West Africa: An Attempt Towards a Regional Typology},pdfauthor={Hippolyte Dossa, Aisha Abdulkadir, Andreas Buerkert, Eva Schlecht},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Multivariate analysis, typology, urban and peri-urban agriculture, West Africa},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{Exploring the Diversity of Urban and Peri"=urban Agricultural Systems in West Africa: An Attempt Towards a Regional Typology\footnote{\textbf{Contact Address:} Eva Schlecht, University of Kassel / University of Göttingen, Animal Husbandry in the Tropics and Subtropics, Steinstraße 19, 37213~Witzenhausen, Germany, \mbox{e-mail}: \email{tropanimals@uni-kassel.de}}\\[0.8ex]}}
\normalsize{\textsc{Hippolyte Dossa$^{1}$, Aisha Abdulkadir$^{2}$, Andreas Buerkert$^{3}$, Eva Schlecht$^{1}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Kassel / University of Göttingen, Animal Husbandry in the Tropics and Subtropics, Germany}}}
\item[]{\small{\textit{$^{2}$Wageningen University, Plant Production Systems Group, Netherlands}}}
\item[]{\small{\textit{$^{3}$University of Kassel, Organic Plant Production and Agroecosystems Research in the Tropics and Subtropics, Germany}}}
\end{itemize*}
\index[author]{Dossa, Hippolyte}
\index[author]{Abdulkadir, Aisha}
\index[author]{Buerkert, Andreas}
\index[author]{Schlecht, Eva}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\small{
Developing appropriate and innovative technologies and policies to respond to the challenges that urban and peri"=urban agriculture (UPA) is facing in West Africa requires a better understanding of the existing production systems. Although there is an increasing recognition of the importance of UPA in the region, its extent, forms and related practices may vary across countries and cities because of different socio"=economic conditions and urbanisation patterns. A systematic classification of the regional UPA systems is still lacking but is necessary to allow for meaningful comparisons between cities and avoid misleading generalisations. The purpose of this study was to determine the proportion of households involved in UPA activities in three West African cities and to classify them into homogenous groups. 700 randomly selected households (250 in Kano, Nigeria, 250 in Bobo-Dioulasso, Burkina-Faso, 200 in Sikasso, Mali) were surveyed using a structured questionnaire. With significant ($p < 0.001$) differences across cities, more households in Bobo-Dioulasso (\mbox{87.6\,\%}) and Sikasso (\mbox{62.5\,\%}) than in Kano (\mbox{41.6\,\%}) were involved in UPA. Subsequently, survey data from 318 households (Kano: 99, Bobo-Dioulasso 111, Sikasso: 108) were submitted to principal components analysis for categorical variables (CATPCA) to reduce the original set of variables (26) to a smaller number. It allowed a mix of variables with different measurement levels to be included in the analysis. Next, the TwoStepCluster method, that handled both the selected continuous (5)~and categorical variables (5) was used to classify the households using object scores obtained from the CATPCA. Diversification of farm activities, farm resource endowment and production orientation were observed to be the major discriminating variables. In each city, four distinct UPA systems were identified, of which three were common to Kano, Bobo-Dioulasso and Sikasso: commercial gardening plus field crop"=livestock (cGCL; \mbox{59\,\%}, \mbox{18\,\%}, and \mbox{37\,\%}), commercial livestock plus subsistence field cropping (cLsC; \mbox{14\,\%}, \mbox{41\,\%}, and \mbox{7\,\%}), and commercial gardening plus semi"=commercial field cropping (cGscC; \mbox{14\,\%}, \mbox{28\,\%}, and \mbox{30\,\%}). The fourth system was location"=specific and could be characterised as follows: semi"=commercial livestock plus commercial gardening in Kano (scLcG; \mbox{13\,\%}), commercial field cropping in Bobo-Dioulasso (cC; \mbox{13\,\%}) and commercial gardening in Sikasso (cG, \mbox{26\,\%}). }

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\noindent \textbf{Keywords:} Multivariate analysis, typology, urban and peri"=urban agriculture, West Africa
\index[key]{Multivariate analysis}
\index[key]{Typology}
\index[key]{Urban!and peri"=urban agriculture}
\index[key]{West Africa}
\end{document}