New economic model finds wetlands provide billions in filtration value
Wetlands in Southern Ontario provide $4.2 billion in water filtration
services each year
Date:
January 25, 2022
Source:
University of Waterloo
Summary:
Southern Ontario wetlands provide $4.2 billion worth of sediment
filtration and phosphorus removal services each year, keeping our
drinking water sources clean and helping to mitigate harmful and
nuisance algal blooms in our lakes and rivers.
FULL STORY ========================================================================== Southern Ontario wetlands provide $4.2 billion worth of sediment
filtration and phosphorus removal services each year, keeping our drinking water sources clean and helping to mitigate harmful and nuisance algal
blooms in our lakes and rivers.
==========================================================================
A new study from the University of Waterloo uses economic valuation to
help us understand the importance of Southern Ontario's wetlands for
water filtration - - particularly as these sensitive ecosystems continue
to be lost by conversion to agriculture or urban development.
"Wetlands naturally filter out phosphorus and sediments from water, but
their value is often greatly overlooked," said Tariq Aziz, who carried out
the study during his PhD and postdoctoral work in Waterloo's Department
of Earth and Environmental Science. "By calculating the economic value
of wetland filtration and comparing it to the costs of engineered interventions, we hope to reinforce the importance of protecting our
wetlands." The total value of $4.2 billion in sediment and phosphorus filtration services was found based on the average rate of sediment
accretion in each type of wetland in Southern Ontario and estimating
how much the removal and disposal of the same amounts of sediment and phosphorus in stormwater management facilities in Ontario would cost.
This is the first economic valuation study to separate the values of
the major types of wetlands in Southern Ontario: marshes, bogs, swamps,
and fens. "We found that marshes were the most valuable wetland type
for sediment and phosphorus filtration, based on the removal rates per hectare," said Aziz.
"However, because swamps make up 87 per cent of Southern Ontario's
wetlands, they contribute about 80 per cent of the overall filtration
services we benefit from, at a value of about $3.4 billion per year."
This study also calculated how much it would cost to replace wetlands'
existing phosphorus filtration function with three different
human-engineered solutions.
Building artificially constructed wetlands would cost an average of
$2.9 billion per year to replace the free phosphorus filtration service
our natural wetlands currently provide. Implementing agricultural Best Management Practices to remove an equivalent phosphorus load would
cost society $13 billion annually, while expanding current wastewater
treatment capacity to replace wetlands' filtration service would cost
$164 billion per year.
========================================================================== Story Source: Materials provided by University_of_Waterloo. Note:
Content may be edited for style and length.
========================================================================== Journal Reference:
1. Tariq Aziz, Philippe Van Cappellen. Economic valuation of suspended
sediment and phosphorus filtration services by four different
wetland types: A preliminary assessment for southern Ontario,
Canada.
Hydrological Processes, 2021; 35 (12) DOI: 10.1002/hyp.14442 ==========================================================================
Link to news story:
https://www.sciencedaily.com/releases/2022/01/220125173258.htm
--- up 7 weeks, 3 days, 7 hours, 13 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)