03 March, 2016

Water-The Basics-From Viv Forbes

Water is essential for all life, and happily it is abundant on our blue watery planet.

However, salty oceans cover 70% of Earth’s surface and contain 97% of Earth’s water. Salt water is great for ocean dwellers but not directly useful for most life on land. Another 2% of Earth’s water is tied up in ice caps, glaciers and permanent snow, leaving just 1% as land-based fresh water.

To sustain life on land, we need to conserve and make good use of this rare and elusive resource.

Luckily, our sun is a powerful nuclear-powered desalinisation plant. Every day, solar energy evaporates huge quantities of fresh water from the oceans. After a stop-off in the atmosphere, most of this water vapour is soon returned to earth as dew, rain, hail and snow – this is the great water cycle. Unfortunately about 70% of this precipitation falls directly back into the oceans and some is captured in frozen wastelands.

Much of the water that falls on land is collected in gullies, creeks and rivers and driven relentlessly by gravity back to the sea by the shortest possible route. Allowing this loss to happen is poor water management. The oceans are not short of water.

Some animals and plants have evolved techniques to maximise conservation of precious fresh water.

Some Australian frogs, on finding their water holes evaporating, will inflate their stomachs with water then bury themselves in a moist mud-walled cocoon to wait for the drought to break. Water buffalo and wild pigs make mud wallows to retain water in their private mud-baths, camels carry their own water supply and beavers build lots of dams.

Some plants have also evolved water saving techniques – bottle trees and desert cacti are filled with water, thirsty humans can even get a drink from the roots and trunks of some eucalypts and many plants produce drought/fire resistant seeds.

Every such natural water conservation or drought-proofing behaviour brings benefits for all surrounding plants and animals.

People have long recognised the importance of conserving fresh water – early settlers built their homes near the best waterholes on the creek and every homestead and shed had its corrugated iron tanks. Graziers built dams and weirs to retain surface water for stock (and fence-crashing wildlife), used contour ripping and good pasture management to retain moisture in soils, and drilled bores to get underground water. And sensible rules have evolved to protect the water rights of down-stream residents.

Rainfall is often a boom and bust affair. Much fresh water is delivered to the land surface suddenly in cyclones, storms and rain depressions. But “The Wet” is always followed by “The Dry”, and droughts and floods are normal climatic events. People who fail to store some of the flood must put up with the drought.

Greens should learn from the beavers. Strings of dams can moderate flood risk, as well as creating drought sanctuaries and secure water for graziers, towns, irrigators and wildlife. Modern cities could not survive without large water storages for drinking water, sanitation, gardens and factories.
Fresh water is also necessary to produce fresh food. We can have fresh milk, butter, cheese, meat, vegetables, nuts and fruit; or we can irrigate the oceans and import fresh food from more sensible countries. And without fresh water and fresh food, there will be no local food processing.

Those infected with the green religion believe we should waste our fresh water by allowing it all to return as quickly as possible to the salty seas. They fight to protect beaver dams and natural lakes, but persistently oppose human dams and lakes. Some even want existing dams destroyed, while wasting billions on energy-hungry desalination and sewerage re-treated plants, pumps and pipelines.

They also want to prohibit man’s production of two drought-defying atmospheric gases, both released by the burning of hydrocarbons – carbon dioxide which makes plants more drought tolerant, and water vapour which feeds the clouds and the rain.

Green water policies are un-sustainable, even suicidal.

Humans must copy the beavers and “Build more Dams”. And help the biosphere by burning more hydrocarbons.

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