SA loses 4% of water supply to non-native plant species, says WWF
South Africa is losing 4% of its water supply to non-native plant species.
This is according to the “Valuing Rivers” report released by the World Wide Fund for Nature (WWF) on Sunday in Stockholm‚ Sweden.
“Non-native species‚ such as eucalyptus‚ are ‘thirstier’ than the native plants they have replaced‚ sucking up through their roots and evaporating an additional 1.4-trillion litres of water per year.”
The report said the loss could quadruple as non-native species spread.
The WWF believes Cape Town is a city which shows that investing in nature-based solutions can ease its dependence on groundwater pumping and desalination during droughts.
“In the watersheds that supply Cape Town’s water‚ restoration of native vegetation can increase available water‚” the report said.
“The broader effort of clearing non-native vegetation to boost water supplies has also employed tens of thousands of people‚ an important co-benefit in a country with 26% unemployment.”
The report highlighted the benefit of healthy and functioning rivers in mitigating natural disasters such as flooding.
Two billion people worldwide rely on rivers for their drinking water while 500m people live on deltas sustained by sediment from rivers. A quarter of the world’s food production relies on irrigation from rivers and 12m tonnes of freshwater fish are caught annually.
The demand for water is growing about 1% annually as consumption patterns change and population growth continues.
The WWF said we run the risk of losing the benefits of rivers if we only consider them as sources of water‚ irrigation‚ navigation‚ flood control and hydropower. Rivers generate 17% of the world’s electricity and provide natural flood protection.
According to the report‚ a fifth of Africa’s GDP (gross domestic product) lies within watersheds with high to very high water risk.