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Observers routinely make errors in almost any visual search task. In previous online experiments, we found that indiscriminately highlighting all item positions in a noisy search display reduces errors. In the present paper, we conducted two eye tracking studies to investigate the mechanics of this error reduction: does cueing direct attention to previously overlooked regions or enhance attention/processing at cued locations? Displays were presented twice. In Experiment 1, for half of the displays, the cue was only presented on the first copy (Cue - noCue) and for the other half, only presented on the second copy (noCue - Cue). Cueing successfully reduced errors but did not significantly affect RTs. This contrasts with the online experiment where the cue increased RTs while reducing errors. In Experiment 2, we replicated the design of the online experiment by splitting the displays into noCue – noCue and noCue – Cue pairs. We now found that the cue reduced errors, but increased RTs on trials with high- contrast targets. The eye tracking data shows that participants fixated closer to items and fixation durations were shorter in cued displays. The smaller fixation-item distance reduced search errors, where observers never fixated the target, for low contrast targets and the remaining low-contrast errors seemed to be recognition errors, where observers looked at the target but quickly looked away. Taken together, these results suggest that errors were reduced because attention was more properly directed to overlooked regions by the cues instead of being enhanced at the cued areas. 

Abstract Tidal wetlands provide valuable ecosystem services, including storing large amounts of carbon. However, the net exchanges of carbon dioxide (CO₂) and methane (CH₄) in tidal wetlands are highly uncertain. While several biogeochemical models can operate in tidal wetlands, they have yet to be parameterized and validated against high‐frequency, ecosystem‐scale CO₂and CH₄flux measurements across diverse sites. We paired the Cohort Marsh Equilibrium Model (CMEM) with a version of the PEPRMT model called PEPRMT‐Tidal, which considers the effects of water table height, sulfate, and nitrate availability on CO₂and CH₄emissions. Using a model‐data fusion approach, we parameterized the model with three sites and validated it with two independent sites, with representation from the three marine coasts of North America. Gross primary productivity (GPP) and ecosystem respiration (R_eco) modules explained, on average, 73% of the variation in CO₂exchange with low model error (normalized root mean square error (nRMSE) <1). The CH₄module also explained the majority of variance in CH₄emissions in validation sites (R² = 0.54; nRMSE = 1.15). The PEPRMT‐Tidal‐CMEM model coupling is a key advance toward constraining estimates of greenhouse gas emissions across diverse North American tidal wetlands. Further analyses of model error and case studies during changing salinity conditions guide future modeling efforts regarding four main processes: (a) the influence of salinity and nitrate on GPP, (b) the influence of laterally transported dissolved inorganic C on R_eco, (c) heterogeneous sulfate availability and methylotrophic methanogenesis impacts on surface CH₄emissions, and (d) CH₄responses to non‐periodic changes in salinity.