how are drought desertification and overpopulation related to darfur?

Answer 1

Here are several interesting sites on that question.
desertification
http://www.worldwatch.org/node/4087
http://seedmagazine.com/news/2006/08/a_hostile_climate.php
http://journals.cambridge.org/action/displayAbstract;jsessionid=AB6AED66C9B5CE964DD5B358E3136742.tomcat1?fromPage=online&aid=684968
overpopulation
http://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article601484.ece
http://fletcher.tufts.edu/news/2007/04/pronk.shtml
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