AimsCoal mining subsidence induces soil collapse/cracking, damaging plant roots and accelerating water loss, which restricts water uptake and exacerbates plant stress. However, the impacts of these stressors on root-xylem hydraulic conductivity and leaf water metabolism remain unclear.MethodsThis study examined three drought levels (no drought, moderate, severe) and root excision intensities (0%, 25%, 50%) on Robinia pseudoacacia root traits, xylem hydraulics, and leaf physiology.ResultsThe results showed fine root length and fine root mass fully recovered to pre-stress levels within one month across all treatments at whole-plant scale. Density-based analysis, however, demonstrated stress-enhanced fine root proliferation in non-excised zones, with root excision exerting predominant control over fine root length density and fine root mass density. The percentage loss of xylem hydraulic conductivity, the maximum xylem specific hydraulic conductivity leaf water potential and leaf gas exchange parameters were affected by drought stress and root excision. Relative contribution analysis indicated that drought stress had the most prominent impact on xylem hydraulic properties. In contrast, for leaf physiological properties, besides the effect of drought stress, the interaction between drought stress and root excision also made a significant contribution.ConclusionFine root regeneration mitigated excision effects, highlighting soil moisture deficit as a critical bottleneck. Given coal resources are mostly in arid regions and climate-driven drought intensification, prioritizing drought mitigation is essential to prevent post-subsidence vegetation degradation.