Research Article

Surface-Applied Biosolids Enhance Soil Organic Carbon and Nitrogen Stocks but Have Contrasting Effects on Soil Physical Quality

Figure 2

Effect of biosolids application for 8 yr (midterm; solid symbols) at four treatment rates on soil water-stable aggregates (1-2 mm; Mg ha−1) in (a) 0–5 cm; (b) 5–10 cm; (c) 10–15 cm; (d) 15–25 cm; (e) 25–35 cm; and (f) whole soil, 0–35 cm. Open symbols show long-term applications of 20 Mg biosolids ha−1 yr−1 for 20 yr (not included in regression shown). The asterisk indicates significant difference between midterm and long-term treatments ().
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