Fifteen Years of Wheat Yield, N Uptake, and Soil Nitrate-N Dynamics in a Biosolids-Amended Agroecosystem. Agriculture, Ecosystems and Environment

Barbarick, K.A. and Ippolito, J.A. and McDaniel, J.P. (2010) Fifteen Years of Wheat Yield, N Uptake, and Soil Nitrate-N Dynamics in a Biosolids-Amended Agroecosystem. Agriculture, Ecosystems and Environment. Agriculture, Ecosystems and Environment. 5 October 2010. pp. 116-120.

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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.

Item Type:	Article
NWISRL Publication Number:	1374
Subjects:	Dryland crops Dryland crops > Small grain Soil > Chemistry > Nitrogen Soil > Soil quality
Depositing User:	Users 6 not found.
Date Deposited:	05 Oct 2010 19:46
Last Modified:	03 Aug 2011 19:19
Item ID:	1404
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/1404