Assessing Taxonomic and Functional Responses of Stream Macroinvertebrate Communities to Multi‐Scale Influences of Urban Land Cover

Urbanization profoundly impacts stream ecosystems, leading to altered hydrology, degraded water quality, and shifts in biological communities, a phenomenon known as the “urban stream syndrome.” This study investigated the taxonomic and functional responses of benthic macroinvertebrate assemblages to urban land cover and local habitat conditions across 22 stream sites in the Nashua River watershed of Massachusetts and New Hampshire. Using a multi‐scale approach, we analyzed land use at watershed, riparian, and reach scales and assessed in‐stream environmental factors, including water quality, substrate composition, and canopy openness. Results indicate that while urban land cover was correlated with increased conductivity and pH, macroinvertebrate taxonomic and functional diversity was more strongly influenced by local habitat conditions such as dissolved oxygen, nitrate levels, and stream width. Sensitive taxa declined in urbanized areas, while opportunistic species with traits favoring rapid reproduction increased. These findings underscore the importance of localized habitat management in maintaining stream biodiversity and highlight the utility of functional trait analysis in urban stream ecology.