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 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 Davis, J. H. Articles by Myrold, D. D. Search for Related Content PubMed Articles by Davis, J. H. Articles by Myrold, D. D. Agricola Articles by Davis, J. H. Articles by Myrold, D. D. Related Collections Isotopes Nutrients Nutrient Cycling

Soil Biology & Biochemistry

Fate of Nitrogen-15 in a Perennial Ryegrass Seed Field and Herbaceous Riparian Area

^a USDA–ARS, Corvallis, OR 97331
^b USDA-ARS, NFSPRC, Corvallis, OR 97331
^c Plant and Environmental Sci., Univ. of California, Davis, CA 95616-8627
^d USDA-ARS, National Program Staff, Beltsville, MD 20705
^e Crop and Soil Sci., Oregon State Univ., Corvallis, OR 97331-7306

^* Corresponding author (griffits{at}onid.orst.edu)

Intensive management of grass seed fields in the poorly drained soils of the Willamette Valley, Oregon, has prompted concern in the capacity of these landscapes and their associated minimally managed riparian areas to process and retain fertilizer N. Our goal was to determine the extent of N losses and effectiveness of a riparian area and an adjacent perennial ryegrass seed field to retain N. The fate of fertilizer ¹⁵NH₄ and ¹⁵NO₃ was determined with a ¹⁵N tracer experiment. During the second year of the study, ¹⁵N recovery in the plant and soil (0–30 cm) from the cropping system was 51% for ¹⁵NH₄ and 43% for ¹⁵NO₃ whereas recovery in the riparian area was only 20% of ¹⁵NH₄ and 31% of ¹⁵NO₃. Greater cropping system retention of ¹⁵N resulted from both greater uptake by the crop and greater retention of ¹⁵N in the soil. Low recovery of ¹⁵N in the riparian area was possibly the result of two significant spring flood events saturating the surface soil of the riparian area but not the cropping system. The prolonged seasonal saturated conditions significantly reduced riparian plant biomass production and N uptake and increased the potential of N loss through overland flow and denitrification. Results indicate that the cropping system had larger available N pools and a larger potential to retain fertilizer N than the riparian zone. However, both areas were prone to substantial loss of applied N.

This article has been cited by other articles:

				J. H. Davis, S. M. Griffith, W. R. Horwath, J. J. Steiner, and D. D. Myrold Denitrification and Nitrate Consumption in an Herbaceous Riparian Area and Perennial Ryegrass Seed Cropping System Soil Sci. Soc. Am. J., September 1, 2008; 72(5): 1299 - 1310. [Abstract] [Full Text] [PDF]

				J. H. Davis, S. M. Griffith, W. R. Horwath, J. J. Steiner, and D. D. Myrold Mitigation of Shallow Groundwater Nitrate in a Poorly Drained Riparian Area and Adjacent Cropland J. Environ. Qual., April 5, 2007; 36(3): 628 - 637. [Abstract] [Full Text] [PDF]