Environment

Sludge: The New Fertilizer

By Paroma BasuJun 1, 2003 12:00 AM

Newsletter

Sign up for our email newsletter for the latest science news
 

Each year the United States generates more than 12 million tons of human and industrial waste, most of which ends up in landfills. So two Florida researchers are helping to resurrect a disposal technique used by farmers during the 1930s: dumping waste on fields to fertilize crops. Martin Adjei, a professor of agronomy at the University of Florida, compared the efficacy of different forms of sludge (liquid, lime-treated, and dried) with that of traditional nitrogen fertilizer on Bahia grass, a common forage crop. Liquid sludge produced as much plant growth as did the chemical fertilizer, and sludge-treated crops contained a higher content of phosphorus, iron, and zinc.

Adjei says fears that toxic household chemicals or infectious bacteria and viruses might persist in sewage sludge are unfounded. Most organic compounds degrade during the treatment process that converts wastewater to sludge, and infectious organisms die when exposed to ultraviolet rays in sunlight. Adjei plans a follow-up study of remnant toxic compounds and heavy metals to prove that liquid-sludge fertilizer is safe and can be used for other crops as well.

1 free article left
Want More? Get unlimited access for as low as $1.99/month
Already a subscriber? Log In or Register
1 free articleSubscribe
Want unlimited access?

Subscribe today and save 70%

Subscribe

Already a subscriber? Log In or Register
More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 70% off the cover price when you subscribe to Discover magazine.

Copyright © 2021 Kalmbach Media Co.