“Water is even a more of a limiting factor than the loss of the land. As an illustration, to produce 7000 kilograms of corn in a hectare it would take a meter of water in the form of rain falling at the proper time on that hectare during the growing season. This is a highly unlikely possibility. That of course is why we use irrigation. But only about 16% of cropland is irrigated. And that irrigated land yields over twice as much food per acre as the non-irrigated land. But irrigation takes huge amounts of water, in fact about 70% of the water that we humans use is used in irrigation. It takes 1400 liters of water to produce just one kilogram of corn. It takes more than twice that much to produce a kilogram of rice.
“You know Wreck that when you estimate water use there are a huge number of variables to consider. For example if you’re talking about growing grains, it takes more water to grow grain in a warm climate where there is a great deal of evaporation or where there is a lot of runoff because of the hardness of the soil. But at least we have some idea of the modern water needed to produce food or manufactured goods. Let me check it on my iPhone now. Here are some estimates from this web page. It says it takes about 520 gallons of water to manufacture a car tire and 62,000 gallons of water to manufacture a ton of steel. Here’s something else on food. It says that it takes about 16,000 liters of water to produce a kilogram of beef, that’s about 2000 gallons of water for pound of meat. And here’s an interesting one. It says that takes 120 gallons of water to manufacture one egg. Can you believe that it takes over 6500 gallons of water to produce the cotton needed for one tee shirt?”
“Interesting! As you might imagine with the increase in population, the per capita amount of irrigated land is continually being reduced. Another problem is that irrigated land, when not using pure rainwater, uses groundwater and other water that has picked up salts. The salts then salinize the soil and, in effect, poison it. This is particularly true in Australia, the US, Mexico, Egypt, Pakistan and India. This salinization results in the loss of about 1% of the world’s farmland annually. Traditionally this has been made up by increasing the amount of land that is irrigated. So today in 2025 we have lost about 25% of the farmland we had at the turn-of-the-century. And in 25 more years we will have lost another 25%. You can understand how these losses are very difficult to make up, especially when we are trying to feed more people every year with less land.
“Then as you can surmise, the runoff of the irrigating water which has been poisoned by pesticides and fertilizers negatively affects the streams and rivers below the irrigated land.”
GLACIER MELT
"And Gulliver Returns" Book 1 Reversing Overpopulation--The Planet's Doomsday Threat Page 32
