A novel dual-threshold assessment method for formulating land degradation neutrality priority governance strategies in Central Asia under SDG 15.3.1

Land degradation (LD) causes significant deterioration in ecosystem services (ESs), which in turn impedes the achievement of global sustainable development goals (SDGs). However, traditional LD assessments often rely on simplified indicators and single-threshold responses, failing to capture the complex, nonlinear dynamics among LD, ESs, and SDGs across diverse environmental contexts. In this study, we focused on the severe LD region in Uzbekistan and proposed a land degradation neutrality priority governance framework based on ESs and SDGs (ES-SDG-LDNPG). A dual-threshold detection method wasemployed to identify critical tipping points in LD responses. The results revealed that LD increased by 17 % between 2000 and 2022, with the most severe impacts occurring in the northwestern temperate desert plain (NWTP) and the southeastern plain-to-mountain transition zone (SPM). ESs decreased by 13 %, with the NWTP, the central arid desert (CAD), and the eastern temperate arid inland basin (ETAB) emerging as critical ecological vulnerability hotspots. Notably, SDG progress decreased by 26 % in the NWTP, highlighting the urgent need for targeted interventions. This study revealed distinct threshold effects of LD on ESs and SDGs across different landscape–climatic zones. When the LDI was below the first threshold A, SDGs progress exhibited negative correlations with LDI, particularly in the NWTP and CAD regions. Once the LDI exceeded the second threshold B, grain production and carbon storage declined sharply in SPM. Under the dual-threshold effect, priority restoration areas were most concentrated in the NWTP (55 %), followed by the SPM and ETAB. These findings emphasize the need for formulating targeted restoration strategies to mitigate LD and support SDG achievement.