High-resolution modeling assesses impact of cities on river ecosystems

In an analysis published in Proceedings of the National

Academy of Sciences, an ORNL-led team used high-resolution geospatial modeling to quantify the effects of land, energy, and water infrastructures on the nation's rivers and streams.
Using streamflow data from the U.S. Geological Survey, the researchers mapped changes to natural hydrology to assess how infrastructure development and competition over  affects the environment at a national scale. Their data-driven approach sheds light on the extent to which water resources and  are affected by urban infrastructures and could help cities curb their burden on regional ecosystems.
The results indicate that urban land transformation and  together affect seven percent of U.S. streams, which influence habitats for more than 60 percent of all North American freshwater fish, mussel, and crayfish species.
"When you consider that most of these streams include big rivers and their major tributaries with abundant species, the environmental impacts are staggering," said lead author Ryan McManamay, an aquatic ecologist with ORNL's Environmental Sciences Division and Urban Dynamics Institute. The study calculated effects on 1,223 fish, mussel, and crayfish species. At least 260 of these are already locally extinct, with many of the remaining classified as endangered.
Additionally, the researchers conducted case studies on five U.S. cities, Atlanta; Knoxville, Tennessee; Phoenix and Tucson, Arizona; and Las Vegas by creating region-specific models to characterize geographical variables and isolate the cities' land-energy-water footprints from the surrounding landscape.


Read more at: https://phys.org/news/2017-08-high-resolution-impact-cities-river-ecosystems.html#jCp