London, ON – Researchers say human encroachment is a threat to aquatic ecosystems across the globe. However, the ability to understand how land-use practices impact these fragile ecosystems has been hindered by the massive scale necessary to conduct accurate field studies.
Enter Western Geography professor Adam Yates and the Thames River Experimental Stream Sciences (TRESS) Centre.
Yates and his partners have constructed a facility where researchers can bring a small part of the natural environment under controlled conditions for testing purposes. The goal is to mimic natural stream conditions using artificial streams to model chemical and physical changes to stream environments. The information generated will give watershed planners and managers insight into potential outcomes of decisions regarding future land use activities.
“This need is particularly strong in such regions as the Thames River Watershed and surrounding lower Great Lakes Basin, where contemporary landscapes present a limited snapshot of possible landscape patterns due to widespread development,” Yates said.
Officially opened this week, the TRESS Centre, located at the Adelaide Pollution Control Plant in London, is comprised of six small tanks containing artificial streams fed by a contaminant-free and regularly monitored water supply from Lake Huron, through the City of London’s drinking water supply system. Medway, Stoney and Pottersburg creeks provide calibration to maximize ecological realism, in order to produce meaningful results.
At the facility, researchers are studying the concentration levels of phosphorus, as well as other nutrients, associated with changes in the ecology of rivers. They hope to identify how many nutrients can be added to a stream before changes in ecology and structure are seen.
Widespread development limits testing in the Thames River Watershed and lower Great Lakes Basin. These outdoor facilities allow Yates to increase experimental control and replication, test stressor effects and investigate the effects of toxic compounds on food webs without harming ‘real’ natural systems.
“It acts like a real stream; blooms mimic full patterns of the real rivers,” said Yates. “Real rivers aren’t consistent in terms of flow, and so algae grows based on the amount of turbulence in the water and the ability to adhere to the rocks. Different species will adapt to different conditions. We can control all that.”
He added phosphorus is the key nutrient for plant growth in most streaming ecosystems.
“It’s critical to have phosphorus in our streams. There is always natural phosphorus in all our rivers, because if there wasn’t we’d have no plant growth or ecology,” said Yates. “The problem is once we get too much phosphorus, we can get shifts in the type of algae that are present in the stream. Plants that would normally be there can’t eat certain types of algae and the streams change the fish (that would be present).”
The TRESS Centre was created through a partnership with the City of London, the Upper Thames River Conservation Authority and Thames River Clear Water Revival. Funding for the project includes the City of London, Environment Canada, Ontario Ministry of the Environment & Climate Change and Natural Sciences and Engineering Research Council.
“Through these partnerships we have been able to do much more than we’d be able to do just as a Western laboratory; we are able to leverage both funding and knowledge,” Yates said. “Because of these connections, we are much better able to generate policy relevant from our science.”
Reported by Paul Mayne, Western News