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Abstract
Freshwater ecosystems are widely regarded as among the world's most threatened and imperiled habitats. This phenomenon is in large part due to the influence of urbanization and the pervasiveness of urban land cover, which has a disproportionate effect on stream environments and has led to the gradual decline of global aquatic biodiversity. In light of the historical impacts of urbanization on stream ecosystems and its continued influence, understanding temporal patterns in the effects of urban development on ecosystem structure and function is a crucial area of focus in the field of stream ecology. The degradation of streams in urban areas can also negatively impact human populations. Therefore, attempts to restore urban streams are common, but are frequently characterized by issues of environmental justice. In this body of work, I pair historical data with contemporary collections of aquatic insects in metropolitan Atlanta, GA, to assess how urbanization and development has modified ecosystem structure and the functional traits of aquatic insect communities through time. Consistent with previous studies, a homogenization and decline of species richness was observed in aquatic insect communities along a gradient of urbanization. This pattern was maintained through time. Additionally, I deployed a standardized assay to estimate how changes in the physicochemical environment of urban watersheds influenced carbon processing, an essential ecosystem function. My research demonstrated that organic matter processing was primarily influenced by microbial-mediated, nutrient immobilization rates characteristic of heavily urbanized sites. Lastly, I examined the process of equitable urban stream restoration, and I used case studies to highlight the social dimensions associated with community stakeholder responses to urban stream restoration. My review detailed the importance of considering societal complexities and socioeconomic capacities before integrating community members in urban stream restoration initiatives.