Effect of the Land Application of Biosolids on Greenhouse Gas Emissions Under Atlantic Canadian Conditions

Abstract

The objective of this field study was to examine the effect of biosolids type, application rate, and application method on soil nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) emissions from a sandy loam textured soil under Atlantic Canadian conditions. Biosolids amendment to soil significantly increased cumulative N2O and CO2 emissions, and had no effect on CH4 emissions as compared to urea and unamended control treatments. Cumulative N2O and CO2 emissions varied with biosolids type due to their different physical and chemical compositions, whereas the application rate or method did not affect N2O and CO2 emissions. Cumulative CH4 fluxes did not vary with biosolids type or application rate but increased from surface spread (SS) treatments as compared to incorporated (INC) treatments. Nitrate and ammonium exposures were not correlated with N2O emissions. Results suggest that land application of biosolids has the potential to increase soil CO2 and N2O emissions, thus a trade-off between improving soil health and high yield versus greenhouse gas emissions must be considered before promoting these practices.