“Loss of wetlands closer to traditional navigable waters must be mitigated under the Clean Water Act by creating new wetlands, or preferably by protecting and restoring similar existing wetlands,” said Dr. John Jacob, Texas AgriLife Extension Service environmental quality specialist. “This ensures that the aquatic integrity of state and federal waters is maintained, because wetlands provide critical ecological services such as pollution removal, among others.”
The study’s findings appear in the journal Wetlands. Jacob said the study suggests that wetlands farther up in the watershed are just as critical to the aquatic integrity of state and federal waters as those that are immediately adjacent to these waters.
“The coastal ‘prairie pothole’ wetlands studied were considered to be hydrologically isolated from traditional navigable waters by the U.S. Army Corps of Engineers, that they are, in effect, essentially closed depressions that contribute little or no water downstream,” Jacob said.
The findings quantify “anecdotal observations” by professionals in the field over many years of substantial runoff coming from the wetlands, said Dr. Brad Wilcox, Texas AgriLife Research rangeland scientist.
“(Our research) suggests surface runoff occurred regularly and accounted for at least 17 percent of watershed precipitation during the 45-month long study,” Wilcox said. “Runoff events averaged 17 days.”
The results of this study have national implications. The difficulty of determining just how far Clean Water Act regulations should extend up into the watersheds above traditional navigable waters has resulted in many lawsuits and a long series of Supreme Court decisions, according to Jacob.
“The most recent decision in 2006 (Rapanos) reinstated the long-standing doctrine of the “significant nexus,” declaring that if such a nexus between wetlands and traditional navigable waters could be quantified, then those wetlands should fall under the jurisdiction of the Clean Water Act,” Jacob said.
“The research we’ve reported here is the first in the country, after Rapanos, to address the nexus issue for a class of wetlands – in this case, coastal prairie potholes on the upper Texas Gulf Coast.”
He said in the anatomy of ecosystems “forests are the lungs and wetlands are the kidneys. But headwater wetlands, like the prairie pothole wetlands we studied, are perhaps more like lymph nodes, acting to filter pollutants in the furthest reaches of the watershed. Given that at least one third of the water in Galveston Bay is derived from runoff which courses through these wetlands, it is critical that we do not lose so many of these wetlands that we can no longer maintain a healthy aquatic ecosystem.”
Jacob said with all the new development and potential loss of wetlands coming to the lower Galveston Bay watershed in the next few decades, there’s a threat of “losing the defenses we need.”
“The quantitative demonstration of a significant hydrological connection between headwater prairie pothole wetlands and Galveston Bay does not mean that development and fill of these wetlands will not take place,” he said. “It does mean, however, that the loss of any of these headwater wetlands should be mitigated, just as is done now for development of wetlands adjacent to Galveston Bay and other waters.
“The mitigation process can be used to protect and restore critical headwater wetlands, which have already largely been identified,” says Jacob. “Prairie pothole wetlands are precisely the wetlands most impacted by development in the greater Houston area. That none of this loss is mitigated puts the health of our waters at grave risk. We now have enough information to know that this loss must be mitigated without delay.”
Jacob also suggests that perhaps not all the loss can be mitigated. Some prairie pothole complexes are so large and unique that their loss cannot really be mitigated.
“You can lose one kidney, but not both,” he said.
Blair Fannin | EurekAlert!
New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign
Fighting a destructive crop disease with mathematics
21.06.2017 | University of Cambridge
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....
A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...
Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision
Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...
21.07.2017 | Event News
19.07.2017 | Event News
12.07.2017 | Event News
21.07.2017 | Earth Sciences
21.07.2017 | Power and Electrical Engineering
21.07.2017 | Physics and Astronomy