Skip to main content
ARS Home » Pacific West Area » Kimberly, Idaho » Northwest Irrigation and Soils Research » Research » Publications at this Location » Publication #254699
Title: Fifteen years of wheat yield, N uptake, and soil nitrate-N dynamics in a biosolids-amended agroecosystem

Author
item BARBARICK, K - Colorad0 State University
item Ippolito, James
item MCDANIEL, J - Colorad0 State University

Submitted to: Agriculture, Ecosystems and Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/8/2010
Publication Date: 10/5/2010
Citation: Barbarick, K.A., Ippolito, J.A., Mcdaniel, J. 2010. Fifteen years of wheat yield, N uptake, and soil nitrate-N dynamics in a biosolids-amended agroecosystem. Agriculture, Ecosystems and Environment. 10.1016/j.agee.2010.07.007.

Interpretive Summary: We investigated 15-years of biosolids application to dryland-wheat, questioning 1) what is the relationship between cumulative grain yield and N uptake (N removal) and biosolids rates and how many times biosolids are applied, and 2) how are wheat-grain production and N uptake intertwined with residual soil nitrate-N? We found that biosolids rates plus the number of applications produced 3-d planar models with 15-years of grain yield and N uptake data. For the biosolids applications, as yield or N uptake increased the residual soil nitrate-N decreased.

Technical Abstract: Understanding N dynamics in biosolids-amended agroecosystems can help avoid over-application and the potential for environmental degradation. We investigated 15-years of biosolids application to dryland-wheat, questioning what is the relationship between cumulative grain yield and N uptake (N removal) and biosolids or N fertilizer rates and how many times biosolids or N fertilizer are applied? How are wheat-grain production and N uptake intertwined with residual soil nitrate-N? We found that biosolids or N fertilizer rates plus the number of applications of each material produced planar-regression (3-dimensional) models with 15-years of grain yield and N uptake data (all R2 > 0.93). To evaluate how yield or N uptake impacted residual soil nitrate-N, we completed linear regressions on yield, N uptake, and soil nitrate-N. We then correlated the slopes where P<0.10 for the yield and soil nitrate-N and the N uptake and soil nitrate-N. A significant negative relationship was found for biosolids application for each of these comparisons while the N fertilizer results were inconsistent. For the biosolids treatments, as yield or N uptake increased, residual soil nitrate-N decreased. Our findings show that planar regression models could aid biosolids beneficial-use management programs when considering agroecosystem N dynamics.