Soils support crop productivity and provide important ecosystem services (such as filtering water and providing a potential sink for greenhouse gases). One of our primary goals for Multistate Project NC1178 is to assess management effects (e.g. crop residue, tillage, cover crops) on soil organic carbon, environmental footprints (e.g. greenhouse gas emissions, water quality, water quantity, soil erosion, input use efficiency), and productivity. For example-- how do different cropping systems influence soil organic matter composition? How does this influence plant and microbial access to N in this organic matter? Stakeholders interested in soil organic matter management, sustainability, and healthy ecosystems will benefit from this work because it will support management decisions that can be used to improve soil organic matter content, resource availability, resource use efficiency, and crop productivity, as well as mitigate greenhouse gas emissions. Our experiments will improve our understanding of soil organic matter dynamics by measuring and characterizing soil organic matter and its interactions with the rest of the soil environment and its inhabitants.