ARS | Publication request: Biosolids application to no-till dryland crop rotations

Submitted to: Colorado State University Technical Report
Publication Type: Experiment Station
Publication Acceptance Date: March 1, 2008
Publication Date: March 1, 2008
Citation: Barbarick, K.A., Ippolito, J.A., Hansen, N.C., Mcdaniel, J.P. 2008. Biosolids application to no-till dryland crop rotations. Colorado State University Technical Report TR08-07. p. 1-17.

Technical Abstract: Biosolids recycling on dryland winter wheat (Triticum aestivum L.) can supply a reliable, slow-release source of nitrogen (N) and organic. Our past research found that continuous application of biosolids from the Littleton/Englewood, CO wastewater treatment facility to dryland winter wheat-fallow rotation provides 16 to 18 lbs N per dry ton. This research involved tilling the biosolids into the top 8 inches of soil. A new question related to soil management in a biosolids beneficial-use program is: How much N would be available if the biosolids were surface-applied in a no-till dryland agroecosystem with winter wheat-fallow (WF) and winter wheat-corn (Zea mays L.)-fallow (WCF) crop rotations? We compared agronomic rates of commercial N fertilizer to an equivalent rate of biosolids in combination with WF and WCF crop rotations. In the wheat plots, we observed similar concentrations of P, Zn, and Cu in wheat grain and surface-soil levels following biosolids or N fertilizer application. We found no differences in soil NO3-N concentrations at depths to 6 feet. We found that biosolids application increased soil salinity (EC) at depths of 4 to 8 and 8 to 12 inches in the wheat plots as compared to N fertilizer applications. Previous biosolids and N fertilizer applications, based on soil test N and crop N requirements, have caused an accumulation of NO3-N in the soil profile. Therefore, near-future biosolids and N fertilizer applications will be ceased until soil NO3-N is reduced by wheat and corn removal.