Assessing multiple ecosystem services in 708 European urban areas.

Nature is increasingly recognized for its potential to address societal challenges in cities, through the delivery of ecosystem services (ES). However, large-scale assessments quantifying this potential are rare. In this study, we modelled five ES (local temperature regulation, flood control, global climate regulation, habitat maintenance, and human interaction with nature) across 708 European urban areas. Using a supply-demand approach, we assessed ES delivery: the extent to which ES supply was sufficient to meet the corresponding societal demands. We found that ES delivery varied both spatially and between ES. On average, nearly 50% of the demand was fulfilled, with the highest values for habitat maintenance (81 ± 15%; mean ± SD), flood control (65 ± 13%), and human interaction with nature (59 ± 15%) and much lower values for local temperature regulation (23 ± 28%) and global climate regulation (16 ± 28%). We further found positive pairwise correlations between all ES (Spearman's ρ from 0.15 to 0.65), with the strongest correlation between habitat maintenance and global climate regulation. Variation in ES delivery across the urban areas was mainly related to differences in the share of green space and the size of the urban areas, whereby ES delivery was positively related to both. Our broad-scale comparative assessment can serve as a starting point for more sophisticated model-based assessments quantifying the full potential of urban nature to meet societal demands across large areas, for example by including a broader set of ES and accounting for city-specific demands. Key policy highlights: Using a supply-demand approach, we modelled five ecosystem services across 708 European urban areas. On average, across ecosystem services and cities, nearly 50% of the ecosystem service demand is fulfilled. We found the highest fulfilled demand for habitat maintenance, flood control and human interaction with nature, and the lowest for local temperature regulation and global climate regulation. Ecosystem service delivery was positively related to the share of green space and the size of the urban areas, and negatively to the share of impervious surface. Our findings underline nature's potential to deliver multiple services simultaneously, while revealing which urban areas may benefit the most from an increase in green space. [ABSTRACT FROM AUTHOR]