Salinization is a pervasive threat to aquatic and terrestrial ecosystems. Increased ionic loads can disrupt cation-anion exchange, biotic uptake, nutrient release, and fundamentally alter dissolved nutrient availability. While salinization alters ecosystem processes experimental studies often examine aquatic and terrestrial systems independently, limiting our understanding of how salinization alters nutrient dynamics across riparian-stream interfaces. In a greenhouse mesocosm experiment, we manipulated NaCl concentrations across an aquatic-terrestrial system by adding 100, 200, 300, 400, and 500 mg/L to soil and water simultaneously (n=5 per treatment). To isolate system-specific responses, 300 mg/L of NaCl was also added to either aquatic or terrestrial components alone. Aquatic systems received constant discharge while terrestrial systems experienced discrete rain events twice per week, simulating rainfall as either saline or freshwater. To assess how orthophosphate, nitrate + nitrate, and ammonia concentrations responded to rainfall through time we analyzed control mesocosms (no NaCl addition), single system controls (aquatic- or terrestrial-only additions), and coupled 300 mg/L NaCl treatment using linear mixed-effect models with rain event type (baseline, freshwater, saline) as a fixed effect and mesocosm as a random effect. Nutrient concentrations were primarily driven by rain event type rather than NaCl addition. Ammonia responded strongly to freshwater rain events exhibiting a parabolic shape with levels decreasing during the summer and subsequently increasing during the fall/winter with baseline and salt rain events had comparable concentrations. Nitrate + Nitrite concentrations were significantly associated with rain event and exhibited a rain event by time interaction resulting in an overall decline through time. In contrast, orthophosphate concentrations showed modest increases through time with limited impacts by rain event. Preliminary results indicate that rain event identity and time exert control over inorganic nutrient pools producing seasonal and nutrient-specific responses. However, these results should be tempered as they are do not account for changes in the total nutrient pool (sodium, chloride, total/organic nitrogen and phosphorus) or responses across all experimental treatments.