Aligning Soil Carbon Science and Policy: Why Is It so Hard to Get It Right?.

For roughly two hundred years scientists have been studying agronomic practices and their impacts on soils, and vice versa.  Today that interest is reflected in ever-greater enthusiasm for tapping the potential to use agronomic systems to create soil carbon sinks, largely as result of concern over growing atmospheric carbon dioxide concentrations.  To make a difference those sinks would need to be stable and at a scale that impacts the global carbon cycle.  Despite increasing talk of achieving negative carbon emissions through the management of natural carbon sinks, there are neither solid data estimates of what is feasible or the policies to make potential sinks a reality. Laws and Gilbert pioneered experiments that included a wide range of manipulations that have provided some of the best examples of the long-term impacts of interventions on soils, but they are the exception and as a result there is limited long-term data.  If soil health is to be linked to climate mitigation more data and less hype is required.  The scientific community needs to reject sloppy data and challenge itself to ensure that the purported synergies between soil and atmospheric goals are not just desirable but supported by the data.  Case studies are important but not sufficient, we need to look at the net benefits of specific practices and how they compare to alternative scenarios.  Comparisons need to be robust and realistic, including limitations on land and organic matter availability.  Both are required for providing a host of other important services, resulting in competition with many climate friendly alternative uses. The soils/agronomic communities, and enthusiasts alike, need to leave boosterism at the door so we can rapidly understand the opportunities and constraints and be seen as honest brokers.