World Losing 2,500 Hectares Of Irrigated Land Per Day To Salt Damage
A study by scientists at the UN University’s Institute for Water, located in Ontario, Canada, revealed that 17 million hectares of arable land has been lost to salinization in the period from 1995 to 2013. The loss rate is computed at a staggering 2,500 hectares per day, or equivalently 4,600 American football fields. Viewed another way, every 4 days the area the size of Manhattan is lost. The total productive land deeply affected by salt now encompasses 62 million hectares (up from 45 million hectares 18 years ago), an area about the size of France. This land area also represents a staggering 20% of irrigatable lands.
Salt degradation occurs due to irrigation with insufficient “leaching fraction”. Irrigation, or the act of adding water to crops, always leaves trace salts near the roots where the plants uptake water but leave solutes. This is because all water, even ostensibly “fresh water” or rain water, contains some amount of salt. If extra water is not added to remove the salt, or if the precipitation is too low, over time salt accumulates leading to salt damage, i.e. reduced productivity and profitability of agricultural practices.
The main author Dr. Manzoor Qadir, the Assistant Director of Water and Human Development at the UN University’s Institute for Water, remarks on the challenge, “To feed the world’s anticipated nine billion people by 2050, and with little new productive land available, it’s a case of all lands needed on deck. We can’t afford not to restore the productivity of salt-affected lands.”
Some of the areas characterized in this study include the Aral Sea Basin in Central Asia, the Indo-Gangetic Basin in India, Indus Basin in Pakistan, Yellow River Basin in China, Euphrates Basin in Syria, Iraq, Murray-Darling Basin in Australia, and the San Joaquin Valley, United States.
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http://www.neomatica.com/2014/10/29/world-losing-2500-hectares-irrigated-land-per-day-salt-damage/
Reminds me of "Idiocracy"
