Unprecedented urban growth has altered ecosystem structure, function, and biodiversity, and consequently the ecosystem services (ES) we depend on. To work towards more sustainable cities, we need to identify opportunities to enhance biodiversity conservation and ES provision. However, our ability to manage for multifunctional urban landscapes requires a better understanding of the relationships among biodiversity, ES, and landscape structure – including consideration of differences among types of urban green space. While there has been a shift towards greater inclusion of private property (e.g., residential yards) in urban ecology research, the extent to which ecological outcomes are generalizable across different green space types remains unclear for many ES. We empirically assessed biodiversity (vegetation diversity, invasive earthworms) and multiple urban ES (carbon storage, water quality regulation, runoff regulation, temperature regulation) across the city of Madison, WI. Sites encompassed private and public green spaces, including both semi-natural (forest, grassland) and developed (parks, residential yards) land. Data were collected over the course of multiple field studies using soil-based biophysical indicators, participatory science approaches, and advanced sensor technology. We synthesized data from these diverse approaches to ask: to what extent does residential land differ from non-residential green spaces in provision of multiple ecosystem services?
Results/Conclusions
Residential yards influenced urban ecosystem service provision both via differences in the type and magnitude of ES provision compared to non-residential green spaces, and by contributing to the amount of green space needed to achieve meaningful changes in some ES. Soil-based ES differed significantly among green space types. Less-developed sites with semi-natural land cover (forests, grassland) supported higher water quality and runoff regulation services (lower phosphorus, higher saturated hydraulic conductivity) compared to residential areas, while residential sites had the highest carbon storage.Temperature regulation services varied non-linearly with changing tree canopy cover, with the most significant cooling occurring in neighbourhoods surpassing ~40% canopy; a largely unreachable threshold without inclusion of residential trees. Biodiversity also differed across green space types. While urban forests supported the highest abundance of an incipient invasive earthworm (Amynthas spp.), presence was highest in residential sites, supporting the hypothesis that residential management influences the spread of invasive species. Results show that consideration of the full mosaic of urban green spaces, including residential yards, leads to improved understanding of the ecology of urban landscapes – allowing ecologists to better speak to the situations and scales at which urban stakeholders have agency over biodiversity and ES provision.