Cocktail of chemicals from many human activities has made US rivers hot and alkaline throughout the United States. Surprisingly, in winter only road salt is not the only source: construction, agriculture and many other activities also act across the region.
Studies conducted by experts at the University of Maryland show that rivers and rivers across the United States have become hotter and more volatile in recent years due to street concentrators, fertilizers and other salty waters that people indirectly emit into rivers It appeared.
Scientists have wandered about the global, regional and local consequences of freshwater chloride syndrome. Scientists have found that salty alkaline fresh water can release a variety of chemicals, including toxic metals and toxic nitrogen compounds from tankers and remains.
The result recommends that a large proportion of the synthetic material travel through the watershed, where only the reference material and a single pollutant make a chemical cocktail that can have a greater impact on water supply and ecosystems.
As they continue their studies, they become aware of the need for new and more comprehensive regulatory and pollution control strategies. They determined the effect of chemical cocktails generated by more detailed saltwater.
They have greatly expanded geographical boundaries of previous research by accessing previously published data from rivers in the US, Europe, Canada, Russia, China and Iran.
According to their analysis, the desalination phenomenon can be a global phenomenon, and the rising trend of salinity ions in the rivers of the US and Europe is steadily increasing. These trends track at least 50 years and some data reach far enough to support the 100-year trend.
Gene Likens, honorary president of the Cary Institute ecosystem research center, co-author of the study, said: "Given what we have discovered, we will be surprised at the extent and size of the Earth's surface waters that have recently deteriorated. It is causing deterioration. "
In snowy Midwest and New England, road salt spraying on winter roads is a major cause of freshwater salinity syndrome. Kaushal and his colleagues conducted a detailed field survey at a river near Washington, DC, and Baltimore to dive deeper into the chemical consequences of road salt.
In one set of observations, the researchers sampled water before, during, and after the snowstorm in 2017 at the Paint Branch stream near the UMD campus. This aspect of the study allowed the team to track the impact of road salt washed into the city with melted snow.
In another series of experiments, the researchers artificially added salt to the Gwynns Falls river near Baltimore to simulate what happens during snowstorms and to measure the copper concentration in water before, during, and after the addition of salt. The downstream data showed a momentary spike of copper from the stream, suggesting a direct connection of copper to the salt content of the stream.
Kaushal added that the salt ion concentration could remain high for several months after the storm. This creates a detrimental cocktail of metal and salt carried farther downstream by extending the time the salt can extract the metal from the soil.
Sujay Kaushal, professor of geology at UMD, said, "Looking at the water quality data over the winter months, the salt remains high and sprinkles salt on the road, with little chance of returning to the baseline before the next storm. There is also evidence that not only does it release metals and other contaminants, but also that the initial salt pulse contributes to the release of other salt ions in stems and soils such as magnesium and potassium, thus keeping the total salinity level high.
Shahan Haq (BS & # 39; 14, physical sciences) and co-author of the study, UMD's geology graduate student, said, "To me, this research highlights the need to view salt as a contaminant from freshwater. The ability of salt to move into the water can have a dangerous impact on our drinking water and toxicity to wildlife. Our observations suggest that some rivers are already at risk, especially in the eastern United States It can be dangerous. "
On December 3, 2018, the researchers published their findings in the Royal Society B's Philosophical Transactions journal.