Abstract: Estuarine zones, as transitional zones between land and sea, exhibit hydrodynamic conditions significantly influenced by tidal forces, which consequently impact water physicochemical properties and greenhouse gas emission processes. The study focused on the Aojiang river basin in Wenzhou City, Zhejiang Province, systematically analyzing spatial variations in aquatic environmental factors during upstream, ebb tide, and flood tide phases. Based on generalized additive models (GAM), it explored the nonlinear response patterns of greenhouse gases to multiple environmental factors. The results indicate that tidal processes significantly alter salinity and dissolved oxygen conditions in estuarine waters. Salinity rises markedly during ebb and flood tides, exhibiting distinct spatial variation. Dissolved oxygen levels decline significantly under tidal mixing, creating hypoxic conditions. In comparison, nutrient indicators such as nitrogen, phosphorus, and organic carbon showed no significant differences. The response of environmental factors to greenhouse gas emissions exhibits distinct nonlinear characteristics. N₂O exhibits a “biphasic” response to water temperature and decreases significantly with increasing salinity. CO₂ increases markedly under high temperature and low dissolved oxygen conditions. CH₄ shows extreme sensitivity to temperature, exhibiting significant fluctuations during tidal-induced temperature changes and being strongly suppressed by high salinity. Based on these findings, it is hypothesized that tidal forces collectively govern greenhouse gas emission patterns in estuarine regions by regulating water salinity, dissolved oxygen levels, and temperature dynamics. The study reveals tidal action regulation of estuarine greenhouse gases, providing crucial scientific evidence for understanding emission mechanisms and assessing the impact on regional carbon budgets.