At present

the ecological restoration of dry ash disposal areas in northwest China principally adopts the mode of simple greening

which generally fails to support the long-term survival of vegetation.Taking the ecological restoration project of a closed dry ash disposal areas in Ningxia as a research case

this study proposes a specialized technical route for ecological remediation of dry ash disposal areas in northern China

covering four modules:ash pile trimming

final capping and covering

grass vegetation establishment

and ancillary works.The integration of ash pile trimming and hardened layer construction not only mitigates construction dust emission

but also enhances the overall stability of the ash disposal areas

providing qualified bearing capacity for subsequent site development and utilization.The combined design of barrier layer and rainwater diversion and drainage layer achieves the dual functions of salt isolation and salt discharge

which cuts off the pathway of salt accumulation to the topsoil from the perspective of water-salt movement

thus reducing the risk of salinization fundamentally.Furthermore

this study innovatively introduces the “physical-chemical-biological” integrated prevention and control measures for salinization

which further eliminates the occurrence of soil secondary salinization.Collaborating with the well-facilitated water-saving irrigation system

this approach adapts to the arid and water-deficient climate in northwest China

and guarantees the long-term stable growth of vegetation.Engineering practice verifies that the proposed scheme features low operational complexity and cost-effectiveness

and has achieved the stable restoration of the regional ecosystem.It therefore boasts promotion and reference value for the ecological restoration of ash disposal areas in northern China

especially in the arid and semi-arid regions of northwest China.