About Us | Help Videos | Contact Us | Subscriptions

Journal of Environmental Quality Abstract - Landscape and Watershed Processes

Evaluating Long-Term Nitrogen- versus Phosphorus-Based Nutrient Management of Poultry Litter


This article in JEQ

  1. Vol. 37 No. 5, p. 1810-1816
    Received: Oct 5, 2007

    * Corresponding author(s): rmaguire@vt.edu
Request Permissions

  1. Rory O. Maguire *a,
  2. Greg L. Mullinsb and
  3. Mike Brosiusa
  1. a Dep. of Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg, VA 24061
    b New Mexico State Univ., PO Box 30001, Las Cruces, NM 88003


Environmental concerns are driving manure management in many areas from a traditional nitrogen (N) basis toward phosphorus (P)-based nutrient management plans. We investigated how changing nutrient management from an N to a P basis affected crop yields and soil properties in high P soils over a 7-yr period. Three sites were established on farmers' fields, and at each site the same six treatments were applied for 6 or 7 yr. These treatments were (i) no P; (ii) poultry litter applied on an N basis; (iii) inorganic P, equal to the P applied in treatment 2; (iv) poultry litter applied on an estimated annual crop P removal basis; (v) inorganic P, equal to the P applied in treatment iv; and (vi) poultry litter applied once every 2 or 3 yr at a 2- or 3-yr crop removal P rate. All treatments received the same rate of plant-available N. Yields, P balance, soil pH, Mehlich 1 P, and water-soluble P (WSP) were monitored during the experiment. Over the course of the experiment, litter had the beneficial effect of raising soil pH relative to the inorganic treatments. After 7 yr, Mehlich 1 P and WSP were greatest in soils under the N-based treatments, smallest in the no P treatment, and intermediate in the P-based treatments. For example, at the Shenandoah site, Mehlich 1 P decreased by 35 mg kg−1 under the no P treatment and increased by 36 mg kg−1 under the inorganic N-based treatment. There were no significant differences between inorganic fertilizer and poultry litter nutrient sources. The results of this study show that soil test P can be decreased in high-P soils over a few years by changing from an N-based to a P-based nutrient management plan or stopping P applications without negatively affecting yields.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2008. American Society of Agronomy, Crop Science Society of America, Soil Science SocietyAmerican Society of Agronomy, Crop Science Society of America, and Soil Science Society of America