Marcus Butler
26 February 2016: An international team of scientists and economists, including experts from the University of Canberra, has called for tougher global salinity regulations to preserve freshwater ecology in a report published in the prestigious journal Science.
The researchers argue that while salinity standards to protect freshwater life are lacking in most of the world, even where they have been enacted they are not sufficient.
Assistant professor in water science Ben Kefford and adjunct associate professor Brenda Dyack from the University's Institute for Applied Ecology, co-authored the report appearing in the latest edition of the peer-reviewed journal.
Dr Kefford said increasing freshwater salinity is a growing problem globally and is likely to worsen in the future due to climate change and increased demand for freshwater.
"Australia and the US are good examples of countries where legislation addresses salinity in freshwater to protect biodiversity, but the existing standards are not clear enough," he said.
"Australian and American standards are based on total salinity; they don't refer to the ionic composition, in other words the exact types of salts that contribute to the total quantity."
The research has found ions are as important to salinity as the total salt content, because they can alter the effects of saline water on living organisms or vegetation in those environments.
"Waters with the same total amount of salts but different ion composition can have markedly different effects on freshwater life," Dr Kefford said.
Environmental and resource economist, Dr Dyack said there are complex issues in developing salinity standards, and there is a need to strike a balance of social, environmental and economic outcomes.
"Australia is leading the world in this respect. Unlike the rest of the world, we require 'triple bottom line' planning under the Water Act (2007), which governs management in the Murray-Darling Basin," Dr Dyack said.
"However, there is more we can do. More specific standards that refer to ionic composition will allow more efficient management of water resources, limit the impact on the wider ecosystem, and deliver greater benefits to communities relying on those freshwater supplies," she said.
"There are a number of approaches that governments could take from our report, including introducing incentives for reducing salinisation," Dr Dyack said.
"Some of our suggestions are ways to make it sensible for enterprises to reduce salinity, including wider introduction of market-based cap and trade schemes; subsidies for technology development and implementation; direct economic incentives to commercialise crops that demand less water; and, fees or charges for those releasing wastewater and run-off that contributes to salinity."
The researchers said that the laws governing how such standards are set need to be flexible and developed with a collaborative approach between science, economic stakeholders and other interested groups.
See the article in Science
