Functional Ecology of Free-Living Nitrogen Fixation: A Contemporary Perspective

Nitrogen (N) availability is thought to frequently limit terrestrial ecosystem processes, and explicit consideration of N biogeochemistry, including biological N 2 fixation, is central to understanding ecosystem responses to environmental change. Yet, the importance of free-living N 2 fixation—a process that occurs on a wide variety of substrates, is nearly ubiquitous in terrestrial ecosystems, and may often represent the dominant pathway for acquiring newly available N—is often underappreciated. Here, we draw from studies that investigate free-living N 2 fixation from functional, physiological, genetic, and ecological perspectives. We show that recent research and analytical advances have generated a wealth…

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  Andrew W. Mellon Foundation