Soil organic carbon (SOC) underpins agricultural sustainability and the terrestrial carbon cycle, yet its vertical distribution and stabilization across soil depth remain poorly constrained at large spatial scales. Here, we present a nationwide, depth‐resolved dataset of SOC and mineral‐associated organic carbon (MAOC)—the more persistent SOC fraction—from 365 dryland cropland sites across China, sampled to 2 m depth. Contrary...

Temperate forests are key terrestrial carbon sinks, yet their capacity to sequester carbon is often limited by nitrogen (N), a nutrient whose availability is declining in many ecosystems. Among factors contributing to declining N availability, climate‐driven changes in soil hydrology could force N loss via the emission of both nitric oxide (NO) and nitrous oxide (N 2 O); however, forecasting these losses is challenging because...