PIM of SPAIN | April 21, 2009 at 08:57 amby
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The vanishing of the Aral Sea is frequently described as an environmental catastrophe. Fortunately in Kazakhstan’s part of the Aral Sea a 13 KM dam project costing over $100 million has been completed in 2005 to save and replenish what remains of the northern, smallest, part of the Aral Sea. That raised the water level of this lake by two metres. Salinity has dropped, and fish again is found in large numbers. As of 2006, recovery of the sea level has been recorded, much sooner than expected. However the outlook for the far larger southern part of the Aral Sea, in neighbouring Uzbekistan remains bleak. The ecosystem of the Aral Sea and the river deltas feeding into it has been practically destroyed, not least because of the much higher salinity. The receding sea has left huge plains covered with salt and toxic chemicals, which are picked up and carried away by the wind as toxic dust and spread to the surrounding area. The land around the Aral Sea is heavily polluted and the people living in the area are suffering from a lack of fresh water and health problems. Crops in the region are destroyed by salt being deposited onto the land. View the video on: http://www.youtube.com/watch?v=EAUyddi_5j8
In China after decades of immense economic growth and the flooding of hundreds of millions of villages and cities, they can't keep up with the demand for water. Another big problem for the Chinese is access to clean water. Between drought and rampant pollution, clean water is becoming more and more scarce.
Of a world population of roughly 6.5 billion, more than 1 billion lack access to drinkable water. About 5 million people die each year from poor drinking water, poor sanitation, or a dirty home environment often resulting from water shortage
Different factors in mismanagement of water and regional troubles cause local shortages. However there is no global water crisis for growing food or other supplies. The question arises whether the world really faces a global water problem? There is plenty of water to go around and human beings are not using all that much. Every year, thousands of cubic kilometres (km3) of fresh water fall as rain or snow or come from melting ice.
At the other hand, an alarming number of the world’s largest rivers in the main grain-growing areas do not anymore reach the sea. For example these are the rivers: Indus, Rio Grande, Colorado, Murray-Darling and world’s sixth largest, almost 5.000 KM long, Yellow-river in China.
The Nile is another worrying case, because Egypt with its huge population is heavily dependent on the Nile’s water, while it is practically tapping out its supply.
In this respect two global trends are of influence and both are likely to accelerate over the coming decades.
The first is demography. Over the past 50 years, as the world’s population rose from 3 billion to 6.5 billion, that roughly trebled the use of water. If current estimates are correct the population will grow by another two billion by 2025 till three billion by 2050. That consequently will increase the demand for water.
The second trend is the changes in foods that are consumed that do need different quantities of water. For example a kilogram of wheat requires around 1,000 litres. But it takes as much as 15,000 litres of water to produce a kilo of beef. Meat diets (US and EU) require for production about 5,000 litres/KG of water a day while vegetarian diets (Asia and Africa) use about 2,000 litres/KG a day. This compared with the use for drinking and washing, which is only 100-250 litres, a day/person.
Climate change increases the problems of water management. In the majority of cases existing water management cannot adequately deal with the larger flooding that often occurs. While most of the time existing reservoirs are too small, or worse, are not available at all to store enough water to last through longer periods of drought. In short, more water will be needed to feed a world that already is using too much. Only better water management, and more conservation through further efficient use of it, as already widely is applied in the industry, will help. This specifically is necessary for agriculture, where an estimated 65% of a country's water resources are misused because only half of it factually does grow crops.
Industrial activities today consume less than 20% of the world’s water. So to get farmers doing the same will make a big difference.
Change in irrigation practices will improve the water efficiency by up to 30%, in accordance to the International Commission on Irrigation and Drainage (I.C.I.D.). Drip-irrigation will bring the water instantly to the roots of the plants. In this respect Israel is very much advanced, they started out in the dessert in 1947 and created within a decennia a modern society through a wonderful efficient water management. Israel with a population of 6.2 million, invented many water-conserving technologies, nevertheless today’s water withdrawals still exceed its resupply form aquifers along the coast. Those now are starting to refill with seawater and consequently polluting its drinking water. Like neighbouring Jordan, Israel is largely dependent on the Jordan River for fresh water.
Change in water pricing is required in agreement to better reflecting supply and demand. Nowadays residents pay for the cost of the pipes that transport it and the sewage system that cleans it. However elsewhere in the countryside there practically is no information and registration about how much water is used and by whom. Rainwater and river flows can be quantified with some accuracy. But the amount of water pumped out of it is guesswork while no information at all is available about the outtake from underground aquifers.
In general the governance of water is a mess. Amongst others: poor countries do not deal with water as a scarce resource, nor do they think about how it would affect their development projects and their future. View also:
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San Diego, California, United States
San Diego, California, United States
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