Before delving into this topic, remember that only 10.6% of the world’s land is arable. A Western life style requires half a hectare per person to sustain it. Only Australia, Kazakhstan, Canada, Niger, Lithuania, Uruguay, Paraguay, Ukraine, Latvia, and Guyana, exceed 0.5 and in that order, ranging from 2.0 to 0.6. Europe and Central Asia average 0.59. The USA has .49 not counting recent flood and drought damage.
Whatever Nature can do man can do better. This is by no means a new boast born of the atomic age. Homo sapiens has always been jealous of the forces in Nature's inventory, and has striven to better them. Nature has always burned large areas of forests with fires started by lightning. How terribly inefficient! Nature must build huge cumulonimbus clouds, marshal great gobs of positive and negative particles, and expend energy equal to a dozen Hiroshima bombs. Even Early Man learned how to do the job by simply rubbing a couple of sticks together or by using a bit of flint. Man made his own forest fires to drive animals to slaughter. This method killed far more animals that could be eaten or used, and it often produced deserts, but why worry? There were lots of forests, lots of animals, and few people. Homo the Sap may not be very good at mathematics or biology, but he has never stopped competing with Nature.
Nature has made lots of deserts, but she has had to exert prodigious effort, both in raising mountain chains to stop moisture-laden winds, and in pushing land masses all over the globe so that large areas are remote from sea breezes. Man, on the other hand, has just plodded away - and look at the beautiful deserts he has created by simple methods:
Irrigation: All you have to do is to apply too much water. This will raise the water table which often permits harmful salt to reach surface layers. This has ruined irrigated areas ever since man started irrigating. Just before the 1979 Soviet invasion, this method created new desert areas in Afghanistan.
Ploughing: Use a "hoe" plough. It cuts a shallow furrow allowing top soil to pulverize into dust and blow away. This ox-drawn plough is still used in the Middle East where once-rich soil now has poor or no yield. Many Syrian towns now lie buried under sand and dust that was once soil on cultivated fields.
Grazing: Sheep and goats are great desert-builders. Unlike cattle, they crop so closely to the ground that plants lose their recuperative powers. Over-grazing and intensive farming around the headwaters of the Tigris and Euphrates caused such heavy erosion that silt, deposited in the Persian Gulf 2,700 km away, extended the coastline of Sumerian times outwards by 300 km in 4,500 years. Over grazing is also a factor in the huge expansion of the Sahara Desert.
Lumbering: Do not let lush vegetation discourage you, particularly in Mediterranean climates that have wet winters and dry summers. A little persistence, like the Greeks used, will do the trick. Greece was once lush and fertile. Remove some trees for ship building, some more for house building, a few to make charcoal for smelting metallic ores, and just a few more to warm the house in winter. Clearing all these forests left good soil for farming, and patient winter rains slowly washed it all into the sea. Yes, you will still find a few olive trees surviving through cracks in the rocks, but that is a desert compared to what once was. The Greeks were not the first at desert-making. The Indus Valley was a great civilization in 1500 BC. Wide streets, flush toilets, and all that. They were good at using charcoal to smelt metals. Each year they had to go a little further out to harvest the trees to make the charcoal. After a few hundred years it does get to be a chore going so far for trees. Apathy and poor workmanship increased enough to so weaken the civilization that Aryians were able to sweep in to murder, rape, and pillage while the deserts grew.
Today, we do things on the grand scale. Throughout the rain forest we are clearing ever increasing areas for farming or ranching or just to sell lumber. The cleared land will support only a few crops before it becomes exhausted and turns to desert, but we can move on. If the environmentalists complain, show them all those small circles of trees that are being left intact. Perhaps they will not stay around to see that this creates large circumferences exposed to the sun and drying. No trees to provide moisture for rain makes more and greater deserts.
Deserts in Lakes and Oceans: Man tries to surpass Nature here. In only 50 years, using industrial wastes and pesticides, he killed Lake Erie, but, in this case, has made some amends. Now, with oil spills and over-harvesting, he is killing the oceans. Take the lush Grand Banks off Newfoundland. In the early 1500's scores of European vessels made three trips per year to fish there among an inexhaustible supply of fish. Then fleets of European and North American trawlers, using sonar and radar, reaped enormous harvests. Factory ships would remain on station year round. This so denuded stocks that Canada imposed a fishing ban in 1992. Thousands went from a life of hard work at sea to collecting welfare cheques.
Excitement was provided by frictions when Canada impounded temporarily a Portugese trawler in 1994 and a Spanish trawler in 1995 for illegal fishing. Spain threatened to send gun boats to protect her right to create ocean deserts.
The Soviet Union, and subsequent entities, have been leaders in water mismanagement. Lake Baikal is badly polluted and the Aral Sea has shrunk dramatically due to the diversion of rivers. Fishing boats are left stranded miles inland.
HOW TO UNMAKE A DESERT:
Man has always destroyed his own creations. Deserts are no exceptions. Planned obsolescence philosophy perhaps? But, how is it done?
Terracing: Where you have removed all that protective covering, you will notice that water really does run down hill. You could terrace that area now to control water flow, but you must wait a thousand years for that bare rock to erode to soil. If you are not that patient, find a virgin area, and terrace it before you remove the trees and grasses.
Wind Breaks and Strip Farming: Treeless plains offer cultivated soils to the winds. Planting rows of tree s and leaving strips of land in natural vegetation will deny the wind the long sweep it needs to be an effective desert-maker. Take a look at Britain and Denmark to see how beautiful this can be. Their hedgerows, hundreds of years old, are wildlife sanctuaries besides preventing erosion, retaining moisture, providing timber, and giving lovers romantic pathways where they can commune with Nature and each other. Some short-sighted farmers are now eliminating hedgerows to plant more crops.
Foam Rubber: This is proving effective in Arabian citrus groves. Planted under the sand it retains humus and moisture.
Oil Spraying: Oil, an excellent pollutant, is now being used to stabilize sand dunes, thus conserving moisture and permitting plants to take root.
Cloud Seeding: Seeding cumulus clouds with silver iodide can cause super-cooled cloud droplets to freeze into ice crystals, releasing latent heat which forces the air in the cloud to rise, causing explosive cloud growth, terminating in seven times more rain than would have fallen had the cloud been left unseeded.
Tree Planting: In the barren, wind-swept areas of Israel, over 77,000,000 trees were planted and carefully nurtured from 1948 to 1961 (35 trees per Israeli). A forbidding land is now becoming a promising one. Many of these now-inhabited areas have not seen human habitation since biblical times. In Africa women are leading the tree-planting effort.
HOW TO MAKE A DESERT WHILE UNMAKING A DESERT:
Aswan Dam: Since 1900 man has increased irrigated acreage 400% to 400 million acres. The Aswan Dam was to have increased this acreage more. The Egyptians worked faster at increasing their population than in building the dam, so the increased acreage was unable to feed the increased population. More problems: Bilharzia, an intestinal and urinary disease, spread because carrier snails are no longer controlled by annual floods and droughts. Nile farmlands have become impoverished because they are no longer renewed by annual deposits of silt. Accumultaed salt, that used to be flushed out by annual flooding, has forced some areas to be taken out of production. And, sardines in the nearby Mediterranean have decreased 33% due to a drop in the amount of nutrients that the Nile used to wash out to sea.
The Great American Desert: Good soil in the southwest needed water. The last ice age left lots of it underground which is now being pumped to create verdant farmlands. This water will soon be all gone and we will need to wait for the next ice age to replenish it. Meanwhile, enjoy the return of the desert.
For this blog we will leave the story there - but adding a PS to argue much more action is required.
PS: COMMON SENSE: Since 1995 there have been 24 UN conferences in 18 different countries to monitor and promote progress in limiting human-made global warming. Germany has hosted four. Only one country, the USA, declined to join the world at the week-long November 2017 conference in Bonn, yet a strong US delegation showed up to insist that they, if not their government, were fully committed.
So, the world has awakened to the threat. Alas, much too little effort exists in the very costly, but essential, removal of carbon already here. Perhaps the subject of a future blog?
Ye Olde Scribe