Tracing the dynamics of animal excreta N in the soil-plant-atmosphere continuum using N-15 enrichment

Abstract

The increased demand for organic farm products, and the attendant restrictions on the use of synthetic N fertilizers in both traditional and organic agriculture, has focused attention on the efficacy of organic sources of N, including animal excreta. However, questions arise in regard to the agronomic and environmental benefits of excreta as alternative sources of N. These questions are best addressed through the experimental use of 15N-enriched excreta, which enable the labeled source to be unequivocally traced through the soil-plant-atmosphere continuum, which N difference or N equivalence techniques cannot achieve. In contrast to organic and inorganic N compounds that can be purchased com..