Land Application of Municipal Sludge with Regard to Cropping Systems and Pollution Potential

摘要

A study was undertaken to demonstrate the potential benefits in using sewage sludge as a soil conditioner/fertilizer on productive agricultural soils in New Jersey. Aerobically-digested liquid sewage sludge was applied to Sassafras sandy loam soil at rates of 0,22.4, and 44.8 metric tons/ha, in the spring of 1977, 1978, and 1979. Groundwater, soil, and crop contamination levels were monitored to determine the maximum sewage solids loading rate permissible without causing environmental deterioration. Application rates between 11.2-16.7 metric tons/ha were found sufficient for providing plant nutrients for the dent corn and rye cropping system studied. Of the trace heavy elements analyzed, iron and zinc levels (24 and 1.3 ppt, respectively) were the highest in the sludge.