How Climatic and Oceanographic Processes and Landscape Fragmentation Together Shape Hydrological Connectivity in a Temperate Estuarine Wetland: The Liaohe River Estuary

Estuarine wetland restoration often rests on the assumption that expanding water surface area equates to restoring ecological function. However, the trade‐offs between artificial interventions and natural hydrological connectivity remain poorly quantified. Focusing on the Liaohe Estuary, a region subject to intense anthropogenic disturbance, we quantitatively disentangled the interactions between natural drivers (climate and ocean dynamics) and anthropogenic landscape modifications. Using a long‐term dataset (1984–2021) from the JRC Global Surface Water Explorer, we applied Graph Theory and Partial Least Squares Structural Equation Modelling (PLS‐SEM) to identify the determinants of hydrological connectivity. Results identify Hydrological Landscape Fragmentation (HLF) as the dominant negative driver of connectivity ( β = −0.443, p < 0.001), indicating that landscape spatial configuration outweighs total water surface area in importance. Crucially, we reveal a ‘connectivity paradox’ driven by Potential Artificial Water Surface (PAWS): whereas PAWS expands water area ( β = +0.302), it simultaneously compromises hydrological connectivity through a significant negative indirect effect (indirect effect = −0.13) by exacerbating fragmentation. Furthermore, contradicting conventional wisdom, we confirm that ocean dynamics and air temperature act as positive controls on connectivity. Our findings suggest that recent restoration projects exhibit ‘fragmented recovery,’ where water area expansion comes at the expense of landscape integrity. Consequently, we argue for a paradigm shift from ‘water replenishment and expansion’ to ‘structural reintegration,’ prioritizing the synergy between landscape connectivity and natural tidal forces.