Carbon-Nitrogen Trade-off Strategies in a Desert Legume under Extreme Drought: A Tracer Study Using 13C/15N Dual Labeling

Drought strongly influences carbon allocation and nitrogen acquisition in desert plants, yet its effects on carbon–nitrogen allocation strategies in desert legumes remain unclear. Using dual ¹³C–¹⁵N labeling, we quantified carbon and nitrogen allocation across the plant–soil–microbe continuum in Alhagi camelorum under well-watered (CK), moderate drought (MD), and severe drought (SD) treatments.