Pelletized Municipal Refuse Compost as a Soil Amendment and Nutrient Source for Sorghum

Abstract The handling, processing, and disposal of solid waste have reached such proportions in the USA as to constitute one of our major environmental problems. Over 480 million metric tons of solid waste are discarded annually by American citizens. In the past, most of this waste was burned in open dumps or deposited in mismanaged landfills. Because of air and water pollution, more satisfactory methods must be developed for solid waste disposal. Composting with efficient machinery under sanitary conditions shows promise in helping to solve this problem. The end product of composting has value as a soil amendment and contains nutrients which are available for plant use. The objective of this study was to evaluate a pelletized compost of much improved physical conditions as compared to other composted municipal refuse. Pelletized compost was used in a greenhouse study as a soil amendment and plant nutrient source after incorporation in Arredondo sand. The application of 8 metric tons/ha of compost increased the yields of two sorghum (Sorghum bicolor L. Moench) crops as compared to the control. Also, the highest rate of compost (64 metric tons/ha) produced higher yields as compared to 10‐4.4‐8.3 fertilizer at 2 tons/ha. Uptake of all plant nutrients measured, except for Mn, was increased by compost applications. In addition, water retention and cation exchange capacity of the Arredondo sand were generally increased by compost applications.