Read at :
http://icardablog.wordpress.com/2012/01/16/new-mapping-methods/
New mapping methods
Wise rainwater harvesting saves crops from failure
Harvest water, not just crops. New mapping methods help planners see where water is available dry areas.
The majority of the world’s farmers live in low-rainfall areas. These farmers could substantially increase their harvests if rainfall were more plentiful. But in fact, water is not as scarce as we think. Even limited supplies can be sufficient, if they are used wisely. That’s where the science of rainwater harvesting comes in.
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