Nitric oxide emissions from the soil to lower levels of the troposphere

Emissions of nitric oxide from the soil to the lower troposphere under varying environmental conditions are considered. NO is a precursor in the formation of tropospheric ozone which can directly impact public health and the environment. Understanding and controlling of NO flux from soils to the troposphere can thus be advantageous, protecting air quality as well as conserving valued nitrogen fertilizers in agricultural settings. Comprehensive laboratory protocols have been developed, conducted, and published that consider the influence of mineral fertilizer, municipal wastewater, municipal wastewater treatment biosolids, swine waste, and toluene on NO emissions with varying soil temperature, moisture content, and pH. Laboratory results indicate that NO emissions from wastewater-amended soil have the highest mean emission rate (63 ng-N/m2s) followed by toluene-amended soil (47 ng-N/m2s), biosolid-amended soil (46 ng-N/m2s), mineral fertilizer-amended soil (44 ng-N/m2s), and then swine waste-amended soil (4 ng-N/m 2s). Results suggest that emissions of NO from soil are an important source of tropospheric NO that further must be considered in soil and air pollution control, research, and policy determinations.

Duke Scholars

Author J. Jeffrey Peirce Civil and Environmental Engineering