Maturity and Stability Evaluation of Composted Yard Trimmings
- 1 March 2003
- journal article
- other
- Published by Taylor & Francis Ltd in Compost Science & Utilization
- Vol. 11 (2), 96-112
- https://doi.org/10.1080/1065657x.2003.10702117
Abstract
The objective of this research was to evaluate a variety of stability and maturity indices for yard trimmings compost produced in the Puget Sound region of western Washington State. Compost samples were collected periodically during a 133-d composting cycle at a commercial composting facility, showing that indices of compost respiration rate were sensitive indicators of compost quality. All respiration rate indices identified a period of high respiration rates during active composting (first 27 d), and a period of relatively stable respiration rates during the latter part of curing (70 to 133 d). Chemical tests of compost solids showed less promise as maturity indicators, but provided valuable information on final compost quality. Mature yard trimmings compost had a C:N of 12, an NH4-N to NO3-N ratio of less than 4, a cation exchange capacity (CEC) of 400 cmol per kg of compost-C, and a pH between 6.5 and Seed germination tests and sensory tests (color and odor) were of limited value in assessing compost maturity. Fully-cured compost produced with forced aeration had a Solvita CO2 test value of 6 to 7 and a respiration rate via the alkaline trap method of 2 mg CO2-C g compost-C−1 d−1. It reheated less than 2°C in an insulated Dewar flask in a 7 d incubation. Further evaluation and calibration of respiration test protocols for compost quality assurance testing programs are recommended.This publication has 14 references indexed in Scilit:
- Influence of sewage sludge compost stability and maturity on carbon and nitrogen mineralization in soilSoil Biology and Biochemistry, 1998
- Transformations of carbon and nitrogen during composting of animal manure and shredded paperBiology and Fertility of Soils, 1998
- Adaptation of Plants to SalinityPublished by Elsevier BV ,1997
- Evaluation of a Field Test Kit for Measuring selected Soil Quality IndicatorsAgronomy Journal, 1996
- Oxygen Respirometry to Assess Stability and Maturity of Composted Municipal Solid WasteJournal of Environmental Quality, 1994
- Recycling of Cattle Manure: The Composting Process and Characterization of MaturityJournal of Environmental Quality, 1993
- Comparison of chemical and microbiological methods for the characterization of the maturity of composts from contrasting sourcesBiology and Fertility of Soils, 1993
- Phytotoxicity due to the agricultural use of urban wastes. Germination experimentsJournal of the Science of Food and Agriculture, 1992
- Evaluation of city refuse compost maturity: a reviewBiological Wastes, 1989
- Saline and Sodic SoilsPublished by Springer Science and Business Media LLC ,1982