Dr Jocelyn Lavallee1, Jennifer L. Soong2, M. Francesca Cotrufo3
1Colorado State University, Fort Collins, United States, 2Lawrence Berkley National Laboratory, Berkeley, United States, 3Natural Resource Ecology Laboratory, Fort Collins, United States
The recognition of fundamental differences between particulate organic matter (POM) and mineral-associated organic matter (MAOM) is not new, but the recent explosion in our understanding of the complexity and heterogeneity of soil organic matter (SOM), coupled with the myriad methodological approaches to studying SOM have overshadowed this conceptual distinction and led to a muddling of ideas. We explore the historical origins and evolution of the POM versus MAOM distinction, weighing supporting evidence and contrasting views. We then use case studies from the SOM literature to demonstrate how assessing mechanisms separately for POM versus MAOM can clarify complicated results and help us move away from context-dependence to more generalizable conclusions that can be used in biogeochemical models. Finally, at a time when many exciting concepts in SOM formation and persistence are emerging and taking shape, we return to the fundamental concept of POM versus MAOM and use this distinction to contextualize new ideas and directions in SOM research and modelling.
Francesca Cotrufo is Professor and Associate Head at the Department of Soil and Crop Sciences, and Senior Scientist at the Natural Resource Ecology Laboratory, at Colorado State University. She earned B.Sc. from the University of Naples, Italy and Ph.D. from Lancaster University, UK. Dr. Cotrufo is internationally recognized for her work on litter decomposition and soil organic matter formation, and for the creative use of isotopic methodologies in these studies. More recently her team developed an integrated measurement-modelling approach to further improve the understanding of the mechanisms and drivers of formation and persistence of soil organic matter, and better predict soil organic matter changes in response to global environmental changes, disturbances, and management practices. Her overall goal is to contribute to the design and development of a research and decision support approach to facilitate soil health improvements and climate change mitigation and adaptation. She is subject editor of the journal Global Change Biology. To date she has published over 100 peer reviewed articles and several book chapters.