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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.

Ban Lim area, Caobang province has proposed high potential of lead-zinc resources, which have occurred in different geological formations. In this paper, based on the collecting, synthetics and processing geological data, especially applied mathematical methods to recognize studied objects of exploration process and quantitative description. The results show that the lead-zinc orebodies in Ban Lim area are mainly occurred in lens-shaped and distributed in layered surfaces of dolomitized limestone of Coc Xo formation. The average lead-zinc content of the orebodies is in a range from 3.27% to 8.33%, its coefficient of variation (Vc) is in a range from 13.71% (evenly) to 137.92% (very unevenly). On the whole, the lead-zinc contents of the orebodies in Ban Lim area mainly comply with the standard normal distribution. The average thicknesses of the orebodies are in a range from 0.92 m to 6.48 m, its coefficient of variation (Vm) is in the range from 8.7% (stable) to 132.95% (very unstable). Quantitative calculation results have shown that Ban Lim lead-zinc deposit belongs to group III of deposits. For the exploration of this type of minerals, it is recommended to use linear grid pattern. Appropriate exploration grid pattern for category 122 reserve is (60-80)×(30-40) m.