Data and code for: Increasing nutrients negatively impact seagrass associated biodiversity

Data and code for: Increasing nutrients negatively impact seagrass associated biodiversity
In this study, we examined epifaunal assemblages associated with Zostera marina meadows at 16 sites spanning lagoon, estuarine, coastal, and island environments around the United Kingdom. Using standardised field sampling in combination with mixed‐effects modelling, we investigated how variation in environmental setting within the seascape, seagrass morphological traits, and leaf tissue nutrient concentrations (nitrogen and phosphorus) shaped patterns of epifaunal abundance, richness, and community composition. Epifaunal assemblages exhibited strong spatial heterogeneity, with local site-level environmental conditions explaining the greatest proportion of variation in community structure. While broader habitat categories provided some explanatory value, seascape level environmental context consistently emerged as the dominant driver. Seagrass morphological traits, including leaf length, width, biomass, and epiphyte cover, had limited influence on epifaunal richness and abundance, suggesting that small-scale habitat complexity was not the primary determinant of biodiversity within these meadows. In contrast, nutrient availability, particularly nitrogen enrichment, had a marked effect on epifaunal diversity.