Elizabeth W. Boyer and Robert W. Howarth, eds., The Nitrogen Cycle at Regional and Global Scales (Dordrecht: Kluwer Academic Publishers, 2002).

This book was produced by the International SCOPE Project on Nitrogen Transport and Transformation: A Regional and Global Analysis, which seeks "to foster the necessary synergism between scientists of many disciplines--marine ecologists, forest ecologists, agricultural scientists, microbiologists, atmospheric chemists, oceanographers and hydrologists--in order to develop new approaches for studying nitrogen cycling. In a collaborative article, Peter Vitousek et al, worked to develop "an ecological understanding of biological nitrogen fixation." An improved understanding of how this process is controlled in nature, helps to understand the causes of nitrogen limitation in the ecosystem. The controls studied include: free-living cyanobacteria, vascular plant symbioses, and heterotrophic bacteria; and the product of the research are new mathematical models.