Missing the input: The underrepresentation of plant physiology in global soil carbon research

Abstract. Plant processes regulating the quantity and quality of soil organic carbon inputs such as photosynthesis, above- and belowground plant growth, and root exudation are integral to our understanding of soil carbon dynamics. However, based on a bibliometric analysis including almost 50 000 scientific papers, we found that plant physiology has been severely underrepresented in global soil organic carbon research. Less than 10 % of peer-reviewed soil organic carbon research published in the last century addressed plant physiological processes relevant to soil carbon inputs. Similarly, plant physiology was overlooked by the overwhelming majority (>90 %) of peer-reviewed literature investigating linkages between soil organic carbon, climate change, and land use and management. These findings highlight that our understanding of soil carbon dynamics and hence the carbon sequestration potential of terrestrial ecosystems is largely built on research that neglects the fundamental processes underlying organic carbon inputs. We advocate that the active engagement of plant scientists in soil carbon research is imperative to shed light on this blind spot. Long-term interdisciplinary research will be essential to develop a comprehensive perspective on soil carbon dynamics and to inform effective policies that support soil carbon sequestration.