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Some creatures need only a little water to survive. Kangaroo rats, for example, get all the water they need from the food they eat. They have very unique kidneys that are so efficient that they can recycle four times more water than human kidneys. By living in deep burrows that shelter them from the desert heat, they are able to conserve most of the water in their body. It is only when hunting for food that they come out of the burrows at night.
Blue Planet
Your have probably learnt from school that nearly three-quarters of Earth's surface is covered with water, but how much of this is freshwater?
97% of the Earth's water is found in the ocean while only 3 percent is fresh water. However, 2 percent of this fresh water exists as ice in the Polar Regions or deep underground. Therefore, we are left with just less than 1 percent of freshwater available for our consumption! This 1 percent of water is usually found in reservoirs, lakes, rivers and shallow underground sources.
Water Everywhere
Many people, plants and animals have had to adapt to an abundance of water and have done so in innovative ways. For example, Cambodia's Great Lake, or Tonle Sap, is a freshwater lake on a tributary of the Mekong River that swells up to 6 times its original size during the monsoon season.
The water from the Mekong River reverses direction and begins flowing up the Tonle Sap River during the intensely rainy monsoon season. The flooding actually brings life to the lake as it becomes a breeding ground for millions of fish such as tiny carp to Mekong giant catfish. Dozens of bird species such as the storks make their home in Tonle Sap. The variety of fishes or food that they eat depend on the type of sediments brought up by the floods.
Not a Drop
In the many places where water is scarce, people and ecosystems show great ingenuity in adapting to the lack of water. Desalination, for example, is a process used to remove salt from seawater to produce fresh water for drinking or farming. How is this possible? High pressure seawater passes through a special membrane which separates the salt water and allows only the fresh water to pass through. This process filters half the seawater into fresh water with the other half as hyper-salty brine.
 Since there is so much seawater, could we not use desalination as a method of obtaining fresh water for our needs? Unfortunately, desalination uses a lot of energy and requires expensive infrastructure.
Today, more than a billion people still cannot get enough safe drinking water to keep them healthy. Clean, plentiful water is not always available where and when it is needed. But many water problems also have solutions. Everyone has a role to play in protecting Earth's water.
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