Freshwater ecosystems supply food, water and energy to billions of people, protect us from droughts and floods, and provide unique habitat for many plants and animals, including one third of all vertebrate species.
These ecosystems range from mangroves shielding our coasts against tsunamis and erosion, to inland lakes and rivers teeming with fish, and wetlands that filter and moderate water flows while storing vast amounts of carbon.
Freshwater ecosystems are particularly degraded. They face pollution from chemicals, plastics and sewage as well as over-fishing and over-extraction of water to irrigate crops, generate power and supply industry and homes.
Rivers face additional impacts from dams, canalisation and mining for sand and gravel. Wetlands are being drained for agriculture, with some 87% lost globally in the last 300 years, and more than 50% since 1900. 1 in 3 freshwater species are threatened with extinction.
Protecting and restoring freshwater ecosystems can involve improving water quality, for instance by treating all waste water before it is discharged. Fishing and mining must be controlled. Dams can be removed or better designed to restore river connectivity, while water extraction can be managed to maintain minimum flows. Returning water flows in peatlands and other wetlands to nature levels restores their ability to prevent stored carbon from reaching the atmosphere.
PADI FIELDS Need Protection Too
Rice paddies are farmed wetlands. Rice is a wetland-dependent (freshwater) plant and the staple food for over half the world’s population. It provides about 20% of the total calorie supply in the world and is grown in at least 114 countries worldwide, particularly in Asia.
Rice paddies are naturally flooded or irrigated fields in which rice is grown. Rice grows with its roots submerged, but with its leaves and seeds (rice) above the water. Rice paddies usually dry out at harvest time, illustrating that these systems shift between aquatic and terrestrial (dry land) phases.
Rice is just one crop. But living in the water in the paddy fields are thousands of species of aquatic organisms. Rural populations benefit directly from some of this biodiversity by harvesting reptiles, amphibians, fish, crustaceans, insects and molluscs for household consumption. But other biodiversity associated with rice paddies supports the health and productivity of the rice itself through, for example, controlling rice pests and helping to make nutrients available to the rice plants.
These wetlands also support the conservation of internationally important populations of resident and migratory waterbirds. (Source: Youth and United Nations Global Alliance)
What YOU Can Do
BECOME AWARE OF WHERE FRESH WATER COMES FROM and how much we depend on it: not just for what we drink, but for personal hygiene, growing our food, and producing energy and the goods we consume.
Do you know: Of the water we consumed (which is only about 0.75 to 1.5 cubic metres per year), much less than 1% is actually used for drinking. We consume much more in other ways, particularly by eating it.
Here are some water requirements to produce typical products:
> Hamburger: 2,400 litres
> Glass of apple juice: 190 litres
> Glass of milk: 200 litres
> Cotton T-shirt: 4,100 litres
> Cup of coffee: 140 litres
> Pair of leather shoes: 8,000 litres
> Cup of tea: 35 litres
> Tonne of steel: 230,000 litres
EAT A SUSTAINABLE DIET. Meat production, especially beef, consumes a great deal of water. The average volume of water (worldwide) required to produce 1 tonne of beef is 15,497 cubic metres; compare this to 1 tonne of chicken (3,918) or 1 tonne of soybeans or barley (1,789 and 1,388, respectively).
REDUCE/ ELIMINATE YOUR USE OF CHEMICALS. Many laundry detergents today are phosphate-free, but this is not the case for most dishwasher detergents. What about the other cleaning, personal hygiene and gardening products you use? Are they really necessary? Find out what they contain and how you can replace them. Most garden chemicals can be avoided by changing the plants grown, gardening practices and accepting a more natural landscape. (Source: Youth and United Nations Global Alliance)