A new study published in the Journal of Environmental pollution by Narcís Prat and Miguel Cañedo-Argüelles, experts of the Department of Ecology of the UB, reveals that climate change and water consumption lead to extreme salinization of rivers.
Although the process of salinization occurs naturally in the environment due to specific geology and climate, human activities such as waste discharge from farming and mining amplify the problem. On a global scale, high river salinity presents a threat to biodiversity, affecting the biological balance of various ecosystems, and ultimately leads to severe economic and public health problems.
The article has an aim to provide an overview and to raise awareness. According to the lead author, Miguel Cañello-Argüelles, the ecological, economic and health implications of salinization are not to be overlooked, considering that the process occurs in many regions around the world.
Although the study is conducted on a local scale, the authors are convinced that the findings are sufficient to diagnose the severity of the problem.
Salinization is becoming increasingly extensive in Europe, as stated by Professor Narcís Prat, director of the Research Group Freshwater Ecology and Management (FEM) of the UB. In Spain, the chemical composition of soils and the type of agricultural activities, result in higher salinity than this in other areas in the world.
In the region of Murcia, the excessive exploitation of water resources and the common irrigation practices cause extreme salinization. This is topped up by the current legislations, which are very flexible in terms of establishing specific limits for salt concentrations in rivers. In the Catalan region, and more specifically the Llobregat River basin, the problem of salinization is combined with extensive pollution caused by mining of potash.
Decalcification of water is another cause of salinization, as it is the case of the Besòs River. This process involves adding of salt to water in order to remove stains caused by lime. The solution to this is to install technologies that can remove excessive salts, however this increases the cost of water potabilization.
The authors of the study outline a number of solutions such as establishing better and stricter legislations and limiting regulations. According to Miguel Cañedo-Argüelles, the reason why such legislations do not exist is mainly because people are not aware that salinization is a threat.
There are some functional management strategies that can be adopted, including setting up a salinity trading scheme, as it is the case in Singleton (Australia). According to the authors, climate change might result in increasing drought, higher water consumption and lower rainfall, which will directly affect the levels of salinity in the Mediterranean region will increase.