Compost Science Complete scientific data on compost process control and end product quality

CURRENT RESEARCH PROJECTS

CSU Summer, 2005, Vol. 13, No. 3, p. 160

CROP RESPONSE
Composition Variability Of Spent Mushroom Compost In Ireland
Investigators: S. N. Jordan, G.J. Mullen and M.C. Murphy, Department of Life Sciences, University of Limerick, Limerick, Ireland
Objectives: To investigate the variability in composition of spent mushroom compost (SMC) in relation to selected physical and chemical parameters and to evaluate its potential for use as a fertilize soil conditioner. SMC was collected from mushroom production units supplied with compost from 13

composting yards in Northern Ireland and the Republic of Ireland. Selected parameters measured included dry matter, organic matter, total N, P and K, C/N ratio; plant-available P and K, pH, EC, total Ca, Mg, Na, Cu, Zn, Fe, Mn, Cd, Cr, Ni, Pb; and cellulose, hemicellulose and lignin constituents.

ENVIRONMENTAL IMPACT
Environmental And Economic Considerations Of Carcass Composting With Particular Reference To Design, Utilization And Biosecurity
Investigators: A. Kalbasi, S. Mukhtar, S. E. Hawkins and B.W. Auvermann; Tehran University, Texas A&M University, Purdue University
Objectives: This review paper notes that size and layout are the two most important design criteria for carcass composting facilities, while bins, static piles and windrows are the most common methods. In their conclusions for the review, the authors note that generally three separate bins (primary, secondary and curing or storage) comprise the bin composting system; organic matter and pH of the final product range from 35 to 70 percent (50-60 percent is optimum) and 5.5 to 8.0 respectively; total annual costs of composting incurred by the livestock sector are about $30/head for cattle and calves, $9/head for weaned hogs, $0.40/head for preweaned hogs, and $5/head for other carcasses including sheep, lambs and goats.

MATERIALS AND METHODS
Use Of A Rotating Drum To Model Household Waste Composting On An Industrial Scale
Investigators: S. Aboulam, B. Morvan; Cemagref, Rennes, France; and J.C. Revel, Ensat, Castanet-Tolosan, France
Objectives: To compare processes occurring and products generated by two scales of composting that included a rotating drum bioreactor and a laboratory pilot plant to simulate what happens on an industrial scale.

Maturity By Compost Analysis In Citrus Waste Composting
Investigators: I. Papastylianou, Agricultural Research Institute, Nicosia, Cyprus; M. Jerzykiewicz, Faculty of Chemistry, Wroclaw University, Poland and Agricultural Research Institute, Nicosia, Cyprus
Objectives: To establish simple, inexpensive composting methods for farmers in Mediterranean climates and to develop assessment methods for compost maturity. Methods for evaluating properly operating processes would involve pH, conductivity, elemental analysis, N forms measurement as well as extractions of humic and fulvic acids. Addition of orange pulp in compost piles was also examined for negative influences. Other study areas concerned fertilization and maturation using more advanced methods like spectroscopies EPR NMR, FTIR.

Establishing Fertilizing Properties And Quality Using Spectroscopic Methods
Investigators: I. Papastylianou, Agricultural Research Institute, Nicosia, Cyprus; M. Jerzykiewicz, Faculty of Chemistry, Wroclaw University, Poland and Agricultural Research Institute, Nicosia, Cyprus
Objectives: To study the chemical composition of organic matter and its change during the composting process, using thermal analysis of compost as well as humic and fulvic acids. Also examined for compost maturity was intensity ratio of absorbances - both aromatic/aliphatic and carboxylic/aliphatic.

MICROBIAL ECOLOGY
Effect Of Different Substrates On Weight And Reproduction Of Earthworms
Investigators: Esperanza Huerta and M. De La Cruz-Mondragon, Unidad Villahermosa, Tabasco, Mexico
Objectives: To study the effect of different substrates on weight and reproduction of Dichogaster saliens, an earthworm common in Mexican agro ecosystems in Tabasco, found in cultures where litter is abundant on the soil surface. Use of earthworms to accelerate process of organic matter degradation and promote use of tropical earthworms has been a central issue for increasing soil fertility in the tropics. Study measured growth and reproduction of D. saliens with substrates normally used in agriculture as green or dry manure.