1 Composting – Waste Alternatives

Disposal of organic waste generated by humans is becoming a problem due to increasing population and rising standards of living (Gray et al., 1971). Florida, in particular, has had rapidly increasing population throughout the past 20 years, thus generating large quantities of waste (Muchovej and Obreza, 2001). From 1990 to 2000, the population increased by 4 million people (Department of Heath, 2009). Traditional disposal methods are no longer adequate to handle the increase in waste. Alternative means of handling wastes need to focus on utilization rather than disposal (e.g. land application). For example, municipal solid waste, animal manure, and vegetable and yard waste have proven by research to be suitable for land application, especially after composting these source materials (Muchovej and Obreza, 2001). The beneficial alternatives to traditional disposal are applying composted solid municipal and yard wastes to agricultural fields. Agricultural soils in Florida have low residual fertility due to erosion, nutrient run-off, leaching, and organic matter loss (Crecchio et al., 2001). Low residual fertility has lead to the recognition that there is a great need for improved soil quality to promote sustainable plant growth (Crecchio et al., 2001). Composting organic wastes is a low external energy input microbial decomposition process that produces CO, water, mineral ions, and stabilized humus-like material (Inbar et al., 1993; Ozores-Hampton et al., 1998; Huang et al., 2000; Stocks et al., 2002). The composting process improves handling by lowering the volume of feedstock to be transported, thus lowering transportation costs. Other benefits of composting wastes for land applications are reduced particle size allowing for uniform field application, increased nutrients, and decreased phytotoxic substances, i.e. high concentrations o