A team of scientists in Taiwan has discovered that wetlands absorb carbon dioxide and weaken the toxic effects of heavily polluted waters, overturning long-held assumptions that wetlands are sources of harmful gases.
“A hectare of wetland teeming with water plants and algae can absorb up to 30 kilograms of carbon dioxide a day,” Lin Hsing-juh, professor of aquatic ecology at National Chung-hsing University, said April 28.
According to Lin, this discovery was unexpected as the dominant view in his field has long been that wetlands tend to release greenhouse gases such as methane and nitrous oxide.
Wetlands can also purify wastewater by diminishing its demand for biochemical and chemical oxygen, making wastewater regions more suitable for wildlife, he added.
Lin and the other researchers on his team reached their conclusion after studying the artificial Daniaopi and Sinhai wetlands in New Taipei City under a three-year research project sponsored by the National Science Council.
“Since the construction of these wetlands in 2006, at least 58 bird species, 152 insects and 85 types of algae have been observed on the riverbanks,” he said. “These findings suggest that man-made wetlands can be an effective way of rehabilitating polluted waterside soil.”
Some of the team’s findings have already been made public at academic conferences and in international peer-reviewed journals such as Ecological Engineering.
Although Taiwan currently has over 100 man-made wetlands, natural ones are still invaluable assets that must be preserved, Lin said.