Soil organic matter (SOM) governs many physical and chemical characteristics of soils, and it is one determinant of a soil's capacity for fertility, ecosystem productivity, and CO2 sequestration. On a global scale, SOM is one of the largest actively cycling carbon (C) reservoirs, and direct human activities impact over 75 percent of C stocks in the upper meter of soil.
Agriculture, grazing, and forestry practices contribute to the loss of SOC in large land areas, but there are opportunities to enhance land productivity and SOC storage in degraded lands-if we improve land-use management practices. "Grazing lands, for example, may represent an untapped global potential for sequestering carbon in soils," explained PNNL researcher and International Soil Carbon Network (ISCN) Scientific Steering Committee member Ben Bond-Lamberty. "If scientists, land managers, land owners, and policymakers work together, we can test whether improved grazing, irrigation, plant species management, and the use of organic or inorganic fertilizers can significantly increase soil C stocks in these lands."
But there are even more challenges. Large areas with and without intentional management are also being subjected to rapid changes in climate, making many SOC stocks vulnerable to losses by decomposition or disturbance.
"Soil affects everyone and everything around us, which makes it a huge challenge not only to get our arms around, but also to coordinate scientific findings from different, but complementary fields of research."
In order to quantify potential losses of SOC or its sequestration at field, regional, and global scales, members of the ISCN posit that improvements in scientific data, modeling, and communication are necessary. Global Change Biology published their perspective on October 5. In it, they also suggest that their network could be a platform for integrating the two scientific communities dominating SOM research: one focused on soil science and soil health and the other focused on the terrestrial C cycle and biogeochemistry.
The ISCN's mission is to improve the understanding of carbon dynamics in soils across the world. But in order to do this, they believe there is a need and an opportunity for the scientific community to take actions, such as:
- better identify datasets to characterize the ecosystem and landscape properties, processes, and the mechanisms that dictate SOC storage and stabilization and their vulnerabilities to change
- identify, rescue, and disseminate existing datasets
- develop platforms for sharing data, models, and management practices for SOC science
- improve the connection between the research communities related to the global C cycle and to soil management
"Soil affects everyone and everything around us," said PNNL researcher Kathe Todd-Brown, "which makes it a huge challenge not only to get our arms around, but also to coordinate scientific findings from different, but complementary fields of research."