Researchers develop environmental water temperature guidelines for SA rivers
Southern Africa is considered a ‘critical region’ of water stress, and scientists have identified the region as a climate change hotspot, expected to warm twice as fast at the global average rate of temperature increase.
In addition to a marked reduction in freshwater available to people, climate change is also making the waters too warm for many other species. Over the past decade, Dr Helen Dallas and colleagues at the Freshwater Research Centre have been investigating the effect of climate change on freshwater ecosystems and the fish and aquatic invertebrates that live there to better-understand the nature of these impacts.
These studies are critical because effective water resource management needs reliable data, and Dr Dallas’ work is providing some of the first insights into what to expect.
From a climate change perspective, climate resilience can be strengthened through healthy ecosystem services that rely on well-functioning river catchments. These ‘services’ refer to the benefits that humans derive from nature, including flood control and water purification that happen naturally when the ecosystems are healthy.
So in essence, maintaining healthy, functioning aquatic ecosystems is critical for both people and biodiversity, but now the challenge is to but this knowledge into action. The next step is to roll out and automate a national water temperature monitoring programme. Dallas says “There is a clear need for the national water temperature monitoring programme” which will allow us to keep tabs on the ecological integrity of our aquatic ecosystems and manage them accordingly.
“This will need to be driven by the government with support from organisations that have a vested interest in tracking long-term change in water temperature. If we can establish a network of thermal monitoring stations, this could offer many benefits to society” Dallas says.
Through a project funded by the Water Research Commission, Dallas and Dr Nick Rivers-Moore recently published a comprehensive technical manual for setting water temperature targets for South Africa’s perennial rivers, and a summary of this is available in Water Wheel magazine.
Download the recently-published environmental water temperature guidelines technical report and manual to find out more about this work.





