HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gale, E. S. Articles by Myhre, E. A. Search for Related Content PubMed PubMed Citation Articles by Gale, E. S. Articles by Myhre, E. A. Agricola Articles by Gale, E. S. Articles by Myhre, E. A. Related Collections Nitrogen Nutrient Management

TECHNICAL REPORTS

Waste Management

Estimating Plant-Available Nitrogen Release from Manures, Composts, and Specialty Products

^a Dep. of Crop and Soil Science, Oregon State Univ., Corvallis, OR 97331
^b Dep. Crop and Soil Sciences, Washington State Univ., 7612 Pioneer Way E., Puyallup, WA 98371
^c Dep. Horticulture, Oregon State Univ. North Willamette Research and Extension Center, Aurora, OR 97002

^* Corresponding author (Dan.Sullivan{at}oregonstate.edu)

Received for publication February 14, 2006. Recent adoption of national rules for organic crop production have stimulated greater interest in meeting crop N needs using manures, composts, and other organic materials. This study was designed to provide data to support Extension recommendations for organic amendments. Specifically, our objectives were to (i) measure decomposition and N released from fresh and composted amendments and (ii) evaluate the performance of the model DECOMPOSITION, a relatively simple N mineralization/immobilization model, as a predictor of N availability. Amendment samples were aerobically incubated in moist soil in the laboratory at 22°C for 70 d to determine decomposition and plant-available nitrogen (PAN) (n = 44), and they were applied preplant to a sweet corn crop to determine PAN via fertilizer N equivalency (n = 37). Well-composted materials (n = 14) had a single decomposition rate, averaging 0.003 d^–1. For uncomposted materials, decomposition was rapid (>0.01 d^–1) for the first 10 to 30 d. The laboratory incubation and the full-season PAN determination in the field gave similar estimates of PAN across amendments. The linear regression equation for lab PAN vs. field PAN had a slope not different from one and a y-intercept not different than zero. Much of the PAN released from amendments was recovered in the first 30 d. Field and laboratory measurements of PAN were strongly related to PAN estimated by DECOMPOSITION (r² > 0.7). Modeled PAN values were typically higher than observed PAN, particularly for amendments exhibiting high initial NH₄–N concentrations or rapid decomposition. Based on our findings, we recommend that guidance publications for manure and compost utilization include short-term (28-d) decomposition and PAN estimates that can be useful to both modelers and growers.

Abbreviations: PAN, plant-available nitrogen • FNE, fertilizer nitrogen equivalency

This article has been cited by other articles:

				J. T. Gilmour Estimating Yield and Yield Response using Computer Simulation of Plant Available Nitrogen from Soil Organic Matter and Manure Soil Sci. Soc. Am. J., January 21, 2009; 73(1): 328 - 330. [Abstract] [Full Text] [PDF]