Soil Nitrogen Levels in a Semiarid Climate Following Long-term Nitrogen Fertilization

Abstract

Fertilizing crested wheatgrass for 14 years with 34 kg/ha or less did not significantly increase the NO3- N concentration in a semiarid soil. Fertilization rates of 56 kg/ha or more resulted in a significant accumulation of NO3- N just above the cemented caliche layer. Total N accumulation in the upper 61 cm of soil from N fertilization levels of less than 56 kg/ha did not exceed 30% of that normally occurring in the profile.