Desert Farming
Juicy and plump, the best tomato I’ve had in my life was grown in the desert. Perhaps the idea may seem strange, but the farming practices, like those demonstrated at the Ramat Negev Research and Development center (RNDARC), make it possible for farmers in dry climates to grow beautiful crops.
My visit to the research center was on a very hot day, about 40 °C (104 °F). It is difficult to grow anything in conditions such as those, but the dry air offers advantages to farmers, that most may not be aware of. I walked through two doorways, pushing the heavy canvas tarps to the side. I was hit with a wave of cool air. Two large black squares of mesh covered the wall to my right blowing cool air. At the opposite end of this building there were fans used to suck air out of the building in order to achieve a balanced pressure.
In desert climates a greenhouse would describe a building with a cooler more humid interior than the exterior air. The process used to achieve such an outcome is called evaporative cooling. By adding water into the air by means of fans, a comfortable climate is achieved for plant life. See the video below for a demonstration of what this system looks like for a greenhouse.
Evaporative cooling is only feasible in desert-like dry climates. The dry hot air absorbs the moisture in exchange for some of its heat. This would not be possible in hotter, more humid climates. As the air becomes more humid, it starts to lose its ability to take more liquid water out of the air.
For example, on a hot dry day, the dry air will allow the sweat on our skin to evaporate nicely in exchange for the sensation of feeling cooler. But if it is a hot humid day, the air is no longer able to evaporate the sweat on our skin. The same principle applies to cooling these green houses.
The moderate temperatures in these greenhouses combined with drip irrigation reduce the amount of wasted water in farming practices. Certain crops, radishes for example, still require traditional spray watering in order to grow properly.
RNDARC: A series of controllers for the irrigation system inside one of the many greenhouses used for agricultural education.
Connection to North America
Aquifers in the southern United States and western states such as California are starting to dry up, and droughts are hitting parts of California harder than ever before. In order to sustain the current level or agricultural production, there will need to be more focus on the practices used to sustain farms. As the climate becomes warmer and drier in some regions, desert farming techniques may become more widely used.
Droughts in California are a severe issue for a major supplier of food throughout North America. Flooding and drought are becoming far worse than they have ever been. Droughts are becoming so bad, that some dams are starting to dry up. (National Geographic, October 2014) Also, wildfire seasons are lasting longer than ever before due to rising temperatures and drought. There are a plethora of problems facing the agricultural industries of the world.
So, what is the point?
The work of the RNDARC has developed farming techniques to: improve crop yields in arid regions, use water efficiently, and make use of saline water irrigation systems. In 2002, a U.S.-Israel initiative increased research and development ties. The Ramat Negev Research Center provides courses and education for farmers. The application of proper agricultural techniques can increase yields, while conserving water.
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