The Use of Variation in the Natural Abundance of 15N to Assess Symbiotic Nitrogen Fixation by Woody Plants

摘要: Deeply rooted woody plants capable of symbiotic N2 fixation are often dominant components plant communities. The importance to the N economy these and overall ecosystem productivity is poorly understood. This a consequence technical difficulties in detecting and/or measuring under field conditions using conventional approaches (i.e., acetylene reduction assay). utility natural 15N abundance approach assess discussed by Shearer Kohl Chapter 20 this volume. analogous isotopic dilution methods widely used agricultural studies except that it takes advantage small deviations soil from atmosphere and, therefore, does not require isotope application soil.