ARS | Publication request: Chemical property of poultry litter amended with selected industrial and agricultural byproducts

Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 28, 2012
Publication Date: N/A

Technical Abstract: The bulk of poultry litter consists of chicken manure and bedding materials. When applied to the soil, litter supplies all essential plant nutrients and serves as a source of organic matter that improves several important soil properties. Litter breaks down in the soil and its soil conditioning effect diminishes within a short time after application. The breakdown of litter and other manures may be slowed by co-applying with certain industrial and agricultural byproducts. The objective of this research was to identify agricultural and industrial byproducts that may alter litter pH and slow its decomposition. Ten materials that included gypsum, cement kiln dust, quicklime, alum, aglime, and biochar were mixed at 20% (dry weight) with rice hull-based litter, placed in open containers, and incubated at ~45% moisture and room temperature. The pH and temperature of the mix was monitored throughout a 97-d incubation period beginning with the first hour. The pH of the un-amended litter at incubation was 8.7 and increased gradually to 9.1 at the end of the incubation. The different byproducts altered the pH to as low as 4 and as high as 12 immediately after mixing. This effect on pH and increases and decreases of mix temperature suggested that the byproducts affected microbial activity and possibly manure decomposition. Un-amended litter lost about 25% of dry mass after 97 d of incubation. Byproducts that increased or decreased the mix pH reduced this loss to as low as 15% suggesting that the decomposition of manures applied to the soil may be slowed by co-applying with selected byproducts.