(AGENPARL) – STATE COLLEGE lun 20 marzo 2023

“Lancaster has extensive GSI implementation, making it an ideal site for the work we’re interested in,” McPhillips said. “They use rain gardens a lot, which are located between the street and the sidewalk. The water comes off the street into these contoured bowls with diverse vegetation where the water accumulates and percolates through the soil, allowing plants to take it up and treat it.”

More than a grain of salt

Plants in GSI, like switchgrass, are chosen for their tolerance to a wide range of moisture conditions, and their deep roots retain water and nutrients. GSI soils — usually sandy with a bit of organic matter — are specifically engineered to help retain contaminants like copper and zinc, both heavy metals commonly found in urban stormwater runoff.

But according to McPhillips, a barrage of salt, used to melt snow and ice in the winter and spring, can severely affect the vegetation and soil’s health, including how well they retain contaminants.

“Salt kicks the metals out of the soil particles,” McPhillips said. “All northern areas with freezing precipitation deal with it. What are ways we can better design GSI so the salt doesn’t impact its ability to treat the stormwater and filter the contaminants?”

Fonte/Source: https://www.psu.edu/news/research/story/greening-grey-engineering-natural-solutions-stormwater-management