Governance - pressure inversion and asynchronous recovery in urbanized coastal ecosystems: A spatially explicit DPSIR assessment of Jiaozhou Bay

Abstract

Traditional environmental assessments often treat urbanized bays as homogeneous units, failing to detect localized degradation hotspots. Consequently, semi-enclosed bays remain the frontline of anthropogenic and natural conflicts where cumulative stressors often outpace resilience, a dynamic often hidden from aggregate metrics. To address these complexities, this study established a high-resolution “Drivers-Pressure-State-Impact-Response” (DPSIR) framework comprising 81 comprehensive indicators. A spatially explicit assessment was conducted across five distinct functional zones (e.g., mariculture, shipping, and wetland conservation areas) in Jiaozhou Bay, China, from 2013 to 2022. Quantitative analysis reveals a distinct recovery trajectory: the composite Environmental Quality Index (EQI) escalated by 135% from 0.31 (“Poor”, Class IV) in 2013 to 0.73 (“Moderate/Good”, Class II–III) in 2022, with 2017 identified as the critical inflection point. After 2017, a “Governance–Pressure Inversion” mechanism emerged, where governance intensity (R) structurally surpassed pollution accumulation (P). This phase transition effectively uncoupled economic growth from environmental degradation. However, recovery was not spatially uniform. We identified a distinct “Asynchronous Recovery” phenomenon: hydrodynamic “dead zones” lagged 2–3 years behind well-flushed areas, constrained by sediment memory effects. These findings challenge “one size fits all” governance models. We propose a “Zone-based Adaptive Management” strategy that prioritizes sediment remediation in the inner bay while focusing on risk prevention in port areas, offering a blueprint for sustainable governance in semi-enclosed coastal ecosystems globally.