Increasing soil carbon sequestration is part of a suite of approaches to reducing atmospheric carbon and addressing climate change. The soil carbon sequestration capability of a landscape is a function of ecological, edaphic, climatic, and anthropogenic factors. Landscape degradation is associated with a loss of soil carbon, but ecological restoration, alternative agricultural techniques, and different land management practices may be able to reverse that trend, increasing carbon sequestration. Recent research has documented the potential of natural infrastructure in dryland streams (NIDS) in aridlands to store carbon in soil on par with wetlands and coastal estuaries. This study compared soil carbon storage and sequestration across different land use types in the Madrean Archipelago Ecoregion, including grazing allotments, agricultural fields, riparian corridors, natural and anthropogenic wetlands, NIDS, reintroduction of native species such as beavers, and restoration sites. Plots consisted of multiple cores which sampled soils at three depths. Samples were analyzed individually for bulk density, pH, and electric conductivity. Composites were made of the cores for each plot at each depth and analyzed for total carbon and total nitrogen. These results and the field locations of the cores and associated field data are presented here as a relational database of 8 comma separated variable files and an entity relationship diagram. Plot photos are included in a zip folder.