Fig. 7 Soil NO₃–N concentrations for the six municipal solid waste compost (MSWC) treatments during laboratory soil incubation. Legend: Open symbols, 0 MSWC + N fertilizer at 0 (circles), 168 (squares), or 336 (triangles) Mg ha^-1, corresponding to 0, 7.5, and 15 mg N 100 g^-1 soil. Solid symbols, 126 Mg ha^-1 MSWC (corresponding to 280 mg 100 g^-1 soil) + N fertilizer at 0 (circles), 168 (squares), or 336 (triangles) kg ha^-1. Error bar indicates LSD (0.05)