Twofold Increase In Yield Research Articles

Uses and benefits of MSW compost: A review and an assessment

Soil incorporation of composted municipal solid waste (MSW) usually results in a positive effect on the growth and yield of a wide variety of crops and the restoration of ecologic and economic functions of land. Agricultural uses of MSW have shown promise for a variety of field crops (e.g., maize, sorghum, forage grasses) and vegetables for human consumption (e.g., lettuce, cabbage, beans, potatoes, cucumbers). Responses by plant systems have ranged from none to over a twofold increase in yield. Specific responses are crop and site dependent. In most cases, yields were highest when composts were applied with fertilizer management programs. In some cases, elevated trace metal uptake was noted with lead and boron of greatest concern. Where long-term monitoring has been possible, benefits persist and actually accrue when sound soil/crop management practices are followed. Levels of toxic elements in plants for human consumption are either not well known or thresholds were not reached, as little mention was made in the literature. Container-grown ornamental crops are not for human consumption and this concern does not apply. However, they are high value commodities, and therefore, safe, satisfactory growth is important. Because composts can replace peats and barks which are becoming expensive, this application shows great promise. Silvicultural or forestry applications also represent a nonconsumptive, potentially large use of compost. These uses range from low volume/high value nursery and Christmas tree applications to high volume/low value uses in forest regeneration. Land reclamation whether for minespoil, landfill cover or soil stabilization as in the establishment and rehabilitation of road shoulders represents another potential beneficial use. However, tonnages recycled in this way will be less than in agriculture and silviculture. Compost utilization will occur in response to a number of factors including their benefits to soil-plant systems, especially those having economic value. As important, however, is the realization by policymakers that composting and compost use in agro or natural ecosystems are an integral part of the entire waste management system. Thus, a systems perspective that includes full cost accounting of waste collection, handling, and processing must incorporate marketing, distributing, and recycling in a life cycle analysis that reflects external costs and societal benefits for composting-based solid waste systems to be competitive.