Urban Soil Quality and Compost.

Urban areas produce large quantities of organic residuals including municipal biosolids and food and yard waste. These can, with appropriate treatment, be transformed into highly beneficial soil amendments for urban agriculture. Benefits associated with use of these amendments in urban soils include improved soil physical properties such as reduced bulk density, increased water infiltration rates, and increased total carbon and nitrogen. In addition, these materials are generally regulated for both pathogen content and metal concentrations. Use of these materials is also beneficial when concerns about soil contamination are a potential obstacle to urban agriculture. Composts or organic residuals based soil amendments will often reduce absolute concentrations of contaminants in soils and may also reduce contaminant bioaccessibility. However, the residuals management agencies in most urban areas are either not aware of this potential market for their products or have neglected to do any outreach or extension. Examples of cases where use of residuals has been integrated into urban agriculture will be presented.