TY - JOUR
T1 - Improving understanding of soil organic matter dynamics by triangulating theories, measurements, and models
AU - Blankinship, Joseph C.
AU - Berhe, Asmeret Asefaw
AU - Crow, Susan E.
AU - Druhan, Jennifer L.
AU - Heckman, Katherine A.
AU - Keiluweit, Marco
AU - Lawrence, Corey R.
AU - Marín-Spiotta, Erika
AU - Plante, Alain F.
AU - Rasmussen, Craig
AU - Schädel, Christina
AU - Schimel, Joshua P.
AU - Sierra, Carlos A.
AU - Thompson, Aaron
AU - Wagai, Rota
AU - Wieder, William R.
N1 - Essential support for this project came from the U.S. Geological Survey (USGS) John Wesley Powell Center for Analysis and Synthesis Working Group on Soil Carbon: \u201CWhat lies below? Improving quantification and prediction of soil carbon storage, stability, and susceptibility to disturbance.\u201D This work was also supported in part by the USDA NIFA HAW01130-H. We thank participants of the International Soil Carbon Network (ISCN) for their help in refining the vision for this manuscript. We are also grateful for feedback from presenters and attendees of our organized oral session at the American Geophysical Union\u2019s 2016 Fall Meeting (\u201CDiving into our conceptual and operational view of soil carbon pools\u201D) and Stefano Manzoni and three anonymous reviewers. Responsible Editor: Karsten Kalbitz.
PY - 2018/8/1
Y1 - 2018/8/1
N2 - Soil organic matter (SOM) turnover increasingly is conceptualized as a tension between accessibility to microorganisms and protection from decomposition via physical and chemical association with minerals in emerging soil biogeochemical theory. Yet, these components are missing from the original mathematical models of belowground carbon dynamics and remain underrepresented in more recent compartmental models that separate SOM into discrete pools with differing turnover times. Thus, a gap currently exists between the emergent understanding of SOM dynamics and our ability to improve terrestrial biogeochemical projections that rely on the existing models. In this opinion paper, we portray the SOM paradigm as a triangle composed of three nodes: conceptual theory, analytical measurement, and numerical models. In successful approaches, we contend that the nodes are connected—models capture the essential features of dominant theories while measurement tools generate data adequate to parameterize and evaluate the models—and balanced—models can inspire new theories via emergent behaviors, pushing empiricists to devise new measurements. Many exciting advances recently pushed the boundaries on one or more nodes. However, newly integrated triangles have yet to coalesce. We conclude that our ability to incorporate mechanisms of microbial decomposition and physicochemical protection into predictions of SOM change is limited by current disconnections and imbalances among theory, measurement, and modeling. Opportunities to reintegrate the three components of the SOM paradigm exist by carefully considering their linkages and feedbacks at specific scales of observation.
AB - Soil organic matter (SOM) turnover increasingly is conceptualized as a tension between accessibility to microorganisms and protection from decomposition via physical and chemical association with minerals in emerging soil biogeochemical theory. Yet, these components are missing from the original mathematical models of belowground carbon dynamics and remain underrepresented in more recent compartmental models that separate SOM into discrete pools with differing turnover times. Thus, a gap currently exists between the emergent understanding of SOM dynamics and our ability to improve terrestrial biogeochemical projections that rely on the existing models. In this opinion paper, we portray the SOM paradigm as a triangle composed of three nodes: conceptual theory, analytical measurement, and numerical models. In successful approaches, we contend that the nodes are connected—models capture the essential features of dominant theories while measurement tools generate data adequate to parameterize and evaluate the models—and balanced—models can inspire new theories via emergent behaviors, pushing empiricists to devise new measurements. Many exciting advances recently pushed the boundaries on one or more nodes. However, newly integrated triangles have yet to coalesce. We conclude that our ability to incorporate mechanisms of microbial decomposition and physicochemical protection into predictions of SOM change is limited by current disconnections and imbalances among theory, measurement, and modeling. Opportunities to reintegrate the three components of the SOM paradigm exist by carefully considering their linkages and feedbacks at specific scales of observation.
KW - Biogeochemical models
KW - Carbon stabilization
KW - Decomposition
KW - Global carbon cycle
KW - Soil organic matter
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U2 - 10.1007/s10533-018-0478-2
DO - 10.1007/s10533-018-0478-2
M3 - Article
AN - SCOPUS:85050994810
SN - 0168-2563
VL - 140
SP - 1
EP - 13
JO - Biogeochemistry
JF - Biogeochemistry
IS - 1
ER -