Carbon‐Transfer Bottlenecks in Irrigated Oasis Agriculture: A Diagnostic Framework for Soil Organic Carbon Retention

Sustaining food production in arid regions increasingly depends on irrigated oasis agriculture, yet high productivity in these systems does not guarantee durable soil organic carbon (SOC) retention. This integrative narrative review asks why this yield–carbon decoupling occurs in irrigated oasis croplands and how it can be addressed through agronomic regulation. We synthesize evidence showing that the key limitation is not biomass input alone, but a set of carbon‐transfer bottlenecks that restrict belowground carbon entry, microbial conversion, and physical–mineral protection. Salinity increases microbial maintenance costs and reduces microbial‐residue formation. Mulched drip irrigation creates wetting and salt‐accumulation microsites that spatially separate carbon inputs from stabilization sites. Long‐term plastic mulching and residual‐film accumulation further degrade soil structure and weaken the matrix needed to protect transformed carbon. The main contribution of this review is to translate established microbial‐efficiency and carbon‐fraction concepts into a diagnostic agronomic framework for oasis cropping systems. This framework links water–salt regulation, substrate–microbe regulation, and soil‐matrix protection to the stage at which carbon transfer is most constrained. Measurable signals from the root zone, microbial pathway, and soil matrix can help identify potential management priorities. By treating regulation as location‐specific rather than sequential, the framework provides a basis for aligning SOC retention with yield stability, water‐use efficiency, climate mitigation, and resilient food production in water‐limited regions.