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his project sought to understand the spatial and temporal patterns and drivers of denitrification in nine accidental wetlands in the Salt River in Phoenix, AZ. Accidental urban wetlands are the result from human activities but are not designed nor managed for any specific purpose; thus, they are useful for examining the effects of both human and non-human drivers of ecosystem processes. For this study, we examined how seasonal monsoon and winter floods affected denitrification in different plant patch types at wetlands with different inundation regimes. Inundation regimes of the study wetlands are driven by storm drains that supply urban baseflow to the wetlands; however, the timing and frequency of discharges differ among storm drains resulting in different durations of inundation. Some storm drains provide enough baseflow that wetlands remain inundated year-round (perennially inundated) while others provide very little baseflow, so inundation is largely in response to rain events (ephemerally inundated). Intermittently inundated wetlands receive enough baseflow to remain inundated for part of the year. At each study wetland, we identified 2-4 dominant plant patch types, including one unvegetated patch. We took 2-4 soil samples from each patch type at each site in each season (pre-monsoon, post-monsoon and winter rainy seasons). We measured denitrification potential, soil organic matter, soil moisture, soil nitrate, soil texture, and water depth. In addition to soil characteristics, we also collected data on plant traits for each patch type. Plant functional traits provide one method to examine mechanistic links between plants and ecosystem processes. Measured plant traits were above- and belowground biomass, above- and belowground C:N ratios, and rooting depth.