Monday, November 5, 2007
99-5
Assessing the Potential for Greenhouse Gas Emissions from Sewage Sludge Amended Soils.
Tomasz Stuczynski, Polish National Research Institute, Institute of Soil Science and Plant Cultivation, Czartoryskich 8, 24-100, Pulawy, Poland and Gregory W. McCarty, USDA-ARS Hydrology and Remote Sensing Laboratory, Bldg. 007, BARC-West, 10300 Baltimore Ave, Beltsville, MD 20705.
Land application of municipal biosolids is the primary means of their disposal. In recent decades, environmental concerns related to land application have focused mainly on risk for soil contamination with heavy metals and organic pollutants as well as on pathogen control. Studies on nutrient leaching have also been common. There is almost no data on potential risk for greenhouse gasses emissions from soils amended with biosolids. To fill this gap, an incubation experiment was conducted with over 40 sludges with diverse properties such as organic matter and its C:N ratio. Biosoilds under study resulted from different sewage treatment and sludge stabilization processes. Cumulative emissions of nitrous oxide and carbon dioxide from a Baltimore soil amended with 10% of biosolids (D.W. basis) were measured during 5 weeks of incubation. The results showed dramatic differences between sludges in their ability to release nitrous oxide and carbon dioxide which in the case of nitrous oxide can differ by an order of magnitude. There is no clear relationship between greenhouse gas emissions and measured properties of the biosolids. This study provides evidence that land application of biosolids may be an important source of greenhouse gas emissions and proper waste management should address this aspect of their quality.