A　variable-stiffness　compliant　control　framework　is　proposed　for　the　issues　of　compliant　manipulation　and　precise　control　of　an　aerial　manipulator　performing　sampling　tasks　in　marsh　wetland　environments.　Firstly,　a　variable-stiffness　admittance　control　method　based　on　energy　tank　is　designed　to　achieve　compliant　sampling　by　the　aerial　manipulator.　Secondly,　a　boundary　adaptive　method　is　proposed　that　effectively　resolves　the　issue　of　insufficient　energy　in　the　energy　tank　caused　by　variable-stiffness　compliance,　enhancing　the　safety　of　the　aerial　manipulator　during　the　sampling　process.　Then,　a　disturbance　observer　and　a　pose　controller　are　designed　using　the　prescribed-time　control　method,　improving　the　disturbance　estimation　and　trajectory　error　convergence　speed　of　the　aerial　manipulator.　The　stability　of　the　proposed　variable-stiffness　compliant　control　framework　is　analyzed　using　passivity　theory　and　Lyapunov　tools.　Finally,　the　compliance,　safety,　and　stability　of　the　variable-stiffness　compliant　control　framework　are　verified　through　simulations　and　experiments.　©　2025　Chinese　Academy　of　Sciences.　All　rights　reserved.