Here are some links to learn from and think about:
Ancient Irrigation: there's nothing new under the sun, really. We just come across the same old challenges for the first time again. The same old solutions should still work, right? Or just invent nano-robots to do all our work... Whichever is easier.
Soil Salinity: this ones for the super nerds out there, and just be glad it isn't an 80 page Word document about the aesthetic qualities of compost. In all seriousness, salinity is a major problem that irrigators need to understand. Many times has a farmer asked us to help him irrigate an already saline area. It just won't work with the methods available to us. A slight salt build up over the course of the irrigation season is no big deal when annual rains wipe the slate clean each year. But if the rains leave a place covered in a white dust of salts and minerals, our method of surface irrigation is not going to help (unless the farmer works very hard, year after year, to leach the root zone). But why add so much work, when farmers are not maximizing their potential on the land they've got?
And that brings us to the final link in today's chain:
Country by country corn crop yields. Malawi isn't listed there, but the trend for Sub-Saharan Africa isn't good. And Malawi is pictured here, with a a negative yield change over last year, which is pretty much what we see here on the ground.
