Study on weed to fight algae
UNIVERSITY of WA-based Centre for Water Research PhD student Maria de la Paz Vilas is investigating whether an introduced water weed keeps toxic algae from West Leederville’s 70ha Lake Monger.
“When there is none of it, a macrophyte called curly leaf pond weed from Europe, it’s been observed that there have been blooms of toxic blue-green algae,” Ms de le Paz Vilas, who previously studied her native Argentina’s River Plate, Patagonia and Antarctic lakes, said.
Contamination and nutrients absorbed by the weed can come from 23 drains that feed and leave Lake Monger.
The contaminants’ sources can include winter overflows from Jolimont’s Mabel Talbot Lake 2km away, in addition to run-off from neighbouring gardens, the adjacent Mitchell Freeway and infill at the City of Stirling.
Ms de le Paz Vilas said her already 18-monthold Town of Cambridge-sponsored study was unusual because it looked at all factors affecting Lake Monger, competition between the weed and phytoplankton in the water.
She wants to know how the weed and plankton recycle the nutrients at the bottom of the 1.2mdeep lake and how weather affects the weed’s role absorbing the nutrients.
This could possibly cause the weed to grow quickly and maybe prevent algae blooms some years.
Cambridge’s $83,000, three-year scholarship has funded her work, including wind, water temperature and contamination measuring devices on buoys at the south and centre of the lake, which are read for results weekly.
From 2010, the Centre for Water Research also completed a Cambridge-backed investigation into the lake’s above and below-ground water flows that carry excess nutrients and run-off to the ecosystem, which evolved as a nutrient-low wetland before colonisation.
Cambridge Mayor Simon Withers said that despite the studies it would still be difficult to control the pollutants’ levels after council mergers because there was still a lot of run-off from the neighbouring Mitchell Freeway, the City of Vincent and City of Stirling infill.
Maria de la Paz Vilas is researching Lake Monger weed, backed the Town of Cambridge Mayor Simon Withers.