Nitrogen from Biosolids Can Help Urban Soils and Plant Growth


The “zero waste” trend could have a friend in the form of biosolids. 

The “zero waste” trend could have a friend in the form of biosolids. Biosolids are the materials produced after domestic waste is treated in urban wastewater systems. In the past, most of this solid material was transferred to landfills. But, processes developed over the past few decades can create “exceptional quality” biosolids.

These new “EQ” biosolids are low in pollutants and pathogens, but high in nutrients. They can be applied to agricultural or urban soils needing fertilizer and other soil health improvements. That reuses a former “waste” material – and helps the environment along the way.

Biosolids are valuable because they are rich in nitrogen, a key nutrient for plants. But, only a fraction of the nitrogen in biosolids used as fertilizer becomes available to plants. This fraction is called bioavailable nitrogen.

“We need to know how much nitrogen becomes bioavailable when we add biosolids to the soil,” says Odiney Alvarez-Campos, a researcher at Virginia Tech. “We want to supply enough for healthy crop growth and yields, but not surplus nitrogen.”

Read more at American Society of Agronomy

Image: Tall fescue grows in an area of urban degraded soil used in this research. The disturbed soil includes a large presence of rocks and foreign materials such as asphalt and cement. (Credit: Odiney Alvarez-Campos)