Ecological deficit mitigation in the Tianshan North Slope: network-driven spatial strategies for ecosystem service flows

• Multi-level framework quantifies dynamic ecosystem flows. • Carbon deficit rose, water surplus turned deficit, food supply–demand ratio has increased by 76.65%. • Ecological output cores reduced to two, Urumqi’s role reversal. • Mid-low altitude ecology improved, with diminishing marginal ecological benefits. • Proposed cross-regional compensation and gradient management to sustain cities. While traditional ecosystem service flow models often emphasize supply-side quantification and lack dynamic transmission mechanisms, this study aims to address these limitations by developing a spatially explicit simulation framework that incorporates multi-level network interactions. Building on improved breakpoint and field strength models, we integrate hierarchical network structures and demand-side constraints to better reflect real-world flow capacities. Based on the spatiotemporal dynamics of water, carbon, and food resources, the framework enables computation of regional deficits, ecological service flows and budgets, with driving mechanisms further explored through the XGBoost-SHAP model. Key findings reveal: (1) From 2000 to 2020, ecosystem service supply–demand patterns in study area changed significantly. The carbon sequestration deficit expanded, exacerbating carbon sink insufficiency. Water yield shifted from surplus to deficit, intensifying water resource conflicts. In contrast, the food production supply–demand ratio grew by 76.65%, indicating stable agricultural productivity. (2) The core of ecological output decreased from three to two. Urumqi has shifted from being an output area to an input area. Localized flow variation rates exceeding 340%, signifying dynamic regional flow restructuring. (3) In 2000, the supply and demand of ecosystem services were mainly affected by DEM, precipitation, and population. By 2020, top-ranked SHAP values declined while lower-ranked ones increased, indicating a shift toward complex interactive mechanisms. The ecology of human settlements in low and medium altitudes has significantly improved, but the marginal effect has decreased. This study suggests optimizing cross-regional ecological compensation and gradient-based management to reduce ecological deficits and boost resilience, offering methodological support for coordinated ecological governance and sustainable urban development.