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To examine relationships between in-stream debris concentrations and different geomorphologic characteristics, catchment characteristics, and catchment and riparian land cover in US urban streams, we collected data on debris (>5 cm), large wood, cross-section and longitudinal profiles, and sediment sizes in 24 stream reaches in two metropolitan areas (Cleveland, Ohio; Charlotte, North Carolina). This dataset supports analyses published in: Farooq, N., Jefferson, A.J., Greising, C., Kearns, K., Muratori, S., Snyder, K. 2025. Prediction of anthropogenic debris and its association with geomorphology in US urban streams. Science of the Total Environment. 975: 179317. doi: 10.1016/j.scitotenv.2025.179317 (open access) https://www.sciencedirect.com/science/article/pii/S0048969725009532 

Anthropogenic debris in urban streams is a persistent environmental problem, yet previous studies have focused largely on how land use influences debris concentrations, while neglecting the potential role of fluvial geomorphology in mediating storage. To examine relationships between in-stream debris concentrations and different geomorphologic characteristics, catchment characteristics, and catchment and riparian land cover in US urban streams, we collected data on debris (>5 cm), large wood, cross-section and longitudinal profiles, and sediment sizes in 24 stream reaches in two metropolitan areas (Cleveland, Ohio; Charlotte, North Carolina). Debris concentrations ranged from 0.18 to 4.7 pieces/m bankfull width, with an average of 1.55 pieces/m. Plastic comprised 71.8 % of the collected debris, and in two reaches with repeated measurements, debris re-accumulated quickly following removal. In city-specific multiple linear regression models, debris concentrations across stream reaches was explained as well or better by geomorphologic variables than GIS variables, but when data from the two cities were combined, the opposite was true. Cross-section characteristics were among the strongest predictors of debris concentration in both cities. Our analysis suggests that roughness associated with stream banks plays an important role in debris storage, through trapping debris on riparian vegetation and by creating width constrictions that lead to low velocity zones and debris settling on the bed. Future work on interactions between bank and vegetative roughness and anthropogenic debris may reveal generalizable predictors of debris storage in urban streams. 

This dataset contains stream bed material size distributions for 39 stream reaches along 12 streams in and near Cuyahoga County, Ohio. All data were collected using the Wolman pebble count technique (Wolman, 1954), in either transect or zig-zag forms (Bunte and Abt, 2001). Data were collected between 2016 and 2023 over the course of several projects. 

Abstract Biological invasions are usually examined in the context of their impacts on native species. However, few studies have examined the dynamics between invaders when multiple exotic species successfully coexist in a novel environment. Yet, long‐term coexistence of now established exotic species has been observed in North American lady beetle communities. Exotic lady beetlesHarmonia axyridisandCoccinella septempunctatawere introduced for biological control in agricultural systems and have since become dominant species within these communities. In this study, we investigated coexistence via spatial and temporal niche partitioning amongH. axyridisandC. septempunctatausing a 31‐year data set from southwestern Michigan, USA. We found evidence of long‐term coexistence through a combination of small‐scale environmental, habitat, and seasonal mechanisms. Across years,H. axyridisandC. septempunctataexperienced patterns of cyclical dominance likely related to yearly variation in temperature and precipitation. Within years, populations ofC. septempunctatapeaked early in the growing season at 550 degree days, whileH. axyridispopulations grew in the season until 1250 degree days and continued to have high activity after this point.C. septempunctatawas generally most abundant in herbaceous crops, whereasH. axyridisdid not display strong habitat preferences. These findings suggest that within this regionH. axyridishas broader habitat and abiotic environmental preferences, whereasC. septempunctatathrives under more specific ecological conditions. These ecological differences have contributed to the continued coexistence of these two invaders. Understanding the mechanisms that allow for the coexistence of dominant exotic species contributes to native biodiversity conservation management of invaded ecosystems.