Flushed resource restores ecosystem

December 09, 2015

Every city has abandoned industrial sites. Encouraging life to return to these barren areas is a challenge. It requires a healthy topsoil for plants and animals to flourish. Cities, with their heavily compacted and often contaminated soils, often struggle to restore blighted spaces. Quality soil is necessary--but not abundant in cities. Enter biosolids.

The Lake Calumet Cluster Site (LCCS) was the home of five U.S steel plants on the southeast side of Chicago. Now it's an 87-acre wasteland of glassy slag--a rocky byproduct of steel manufacturing.

"It's a mess," says Nick Basta, "Sixty percent of the land is bare rock."

The site used to be a wetland, but years of infill, dumping, and excavation has rendered the area inhospitable to plants and animals. It is on the EPA's national priority list. Over the last few years, the city has tried to restore the area. The hope is that it will become a stop for migratory birds along Lake Michigan's shoreline.

Restoration efforts of this scale are difficult. The original plan put forth by the restoration team was a two-inch layer of compost on the site. To Basta, this wasn't the answer.

"I love compost, but it's just not good enough," he said. A good soil provides the right combination of depth, nutrients, and texture to support bacteria, fungus, insects, and worms. Compost lacks essential plant nutrients, and is easily dispersed by rain and wind. A soil teeming with microscopic life is ideal for restoring plant and animal communities.

Basta and his team from the School of Environment and Natural Resources at Ohio State University, along with Lakhwinder Hundal and Kuldip Kumar from the Chicago Metropolitan Water Reclamation District (MWRD), decided to manufacture their own soil with help from the nearby wastewater treatment plant.

Chicago's MWRD makes creative use of the enormous amount of waste Chicago generates. One example is biosolids--a rebirthing of sewage into a clean, pathogen-free, nutrient-dense growing material. Two years of physical, chemical, and biological treatment turns what was once sludge into a rich growing medium. These biosolids have a wealth of organic matter and are full of plant nutrients. It's an ideal base for diversity. In July 2015, Illinois legislation declared biosolids an approved resource for healthy lawns and growing crops.

Basta and his team collaborated with MWRD to create a soil blend using biosolids. "We called it the dream treatment," said Basta. They tilled it into test plots just outside the LCCS site. Researchers created a second plot with compost--a thick, organic-rich material degraded from hardwood trees. The team scattered native plant seeds on both plots.

The biosolids plots proved to be the best home for healthy bacteria, fungus and plants--important indicators for a thriving ecosystem. Worms were happy in both the compost and biosolids plots.

"The next step is blending the biosolids and the compost," said Basta.

The city of Chicago already uses biosolids for golf courses and baseball diamonds. Basta hopes that biosolids can restore the degraded surface area of LCCS, and the poor quality soils typical in Chicago's dense urban areas.

"You have to bring in the soil," said Basta "Why not connect the dots and bring in what's available locally?"

Read more about the "dream treatment" in a special section of the Journal of Environmental Quality, "Soil in the City."
-end-


American Society of Agronomy

Related Plants Articles from Brightsurf:

When plants attack: parasitic plants use ethylene as a host invasion signal
Researchers from Nara Institute of Science and Technology have found that parasitic plants use the plant hormone ethylene as a signal to invade host plants.

210 scientists highlight state of plants and fungi in Plants, People, Planet special issue
The Special Issue, 'Protecting and sustainably using the world's plants and fungi', brings together the research - from 210 scientists across 42 countries - behind the 2020 State of the World's Plants and Fungi report, also released today by the Royal Botanic Gardens, Kew.

New light for plants
Scientists from ITMO in collaboration with their colleagues from Tomsk Polytechnic University came up with an idea to create light sources from ceramics with the addition of chrome: the light from such lamps offers not just red but also infrared (IR) light, which is expected to have a positive effect on plants' growth.

How do plants forget?
The study now published in Nature Cell Biology reveals more information on the capacity of plants, identified as 'epigenetic memory,' which allows recording important information to, for example, remember prolonged cold in the winter to ensure they flower at the right time during the spring.

The revolt of the plants: The arctic melts when plants stop breathing
A joint research team from POSTECH and the University of Zurich identifies a physiologic mechanism in vegetation as cause for Artic warming.

How plants forget
New work published in Nature Cell Biology from an international team led by Dr.

Ordering in? Plants are way ahead of you
Dissolved carbon in soil can quench plants' ability to communicate with soil microbes, allowing plants to fine-tune their relationships with symbionts.

When good plants go bad
Conventional wisdom suggests that only introduced species can be considered invasive and that indigenous plant life cannot be classified as such because they belong within their native range.

How plants handle stress
Plants get stressed too. Drought or too much salt disrupt their physiology.

Can plants tell us something about longevity?
The oldest living organism on Earth is a plant, Methuselah a bristlecone pine (Pinus longaeva) (pictured below) that is over 5,000 years old.

Read More: Plants News and Plants Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.