Land‑use change across watersheds is a major driver of variation in the abiotic and biotic dynamics of stream ecosystems. Converting natural forest cover to agricultural, silvicultural, or urban uses can elevate sediment inputs, alter hydrology, and modify nutrient regimes, ultimately restructuring stream communities and reducing overall ecosystem function. Using standardized leaf‑pack assays, we evaluated how dominant watershed land‑cover types (Urban, Silviculture/Pine, Natural Forest, and Agriculture) influence detrital decomposition rates and aquatic macroinvertebrate assemblages in streams of southeast Georgia. Because decomposition integrates microbial activity and macroinvertebrate processing, leaf‑pack breakdown provides a robust indicator of stream ecosystem function, while the colonizing macroinvertebrates serve as widely used bioindicators of ecological condition. Detrital processing rates differed across land‑use categories, with agriculturally dominated watersheds exhibiting the highest decomposition rates relative to forested, plantation, and urban systems. Macroinvertebrate communities also varied with land use: disturbed watersheds (Urban and Agricultural) were characterized by assemblages dominated by tolerant taxa, whereas forested watersheds supported more diverse and functionally complex communities. These patterns highlight watershed land use as a key determinant of both stream ecosystem function and biological integrity. This project represents the southeastern U.S. component of a broader global effort to assess how land‑use gradients shape freshwater ecosystem processes and community structure. By integrating our regional findings with those of international collaborators, this work contributes to a growing understanding of how freshwater ecosystems respond to accelerating landscape change and helps build the predictive capacity needed to support resilient watersheds in a rapidly changing world.