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[Display omitted] • A holistic assessment of greenspace exposure across space and scale in China. • Greenspace exposure assessment was conducted at province, city, county, town, and parcel levels. • Greenspace coverage rate overestimates greenspace exposure in East China and underestimates in West China. • Newly urbanized areas have better greenspace exposure than older urban areas. Greenspace exposure metrics can allow for comparisons of green space supply across time, space, and population groups, and for inferring patterns of variation in opportunities for people to enjoy the health and recreational benefits of nearby green environments. A better understanding of greenspace exposure differences across various spatial scales is a critical requirement for lessening environmental health disparities. However, existing studies are typically limited to a single city or across selected cities, which severely limits the use of results in measuring systemic national and regional scale differences that might need policy at above individual city planning level. To close this knowledge gap, our study aims to provide a holistic assessment of multi-scale greenspace exposure across provinces, cities, counties, towns, and land parcels for the whole of China. We mapped the nationwide fractional greenspace coverage at 10 m with Sentinel-2 satellite imagery, and then modeled population-weighted greenspace exposure to examine variation of greenspace exposure across scales. Our results show a prominent scaling effect of greenspace exposure across multi-scale administrative divisions in China, suggesting, as expected, an increase in heterogeneity with finer spatial scales. We also identify an asymmetric pattern of the difference between greenspace exposure and greenspace coverage, across a geo-demographic demarcation boundary (i.e., along the Heihe–Tengchong Line). In general, the greenspace coverage rate will overestimate more realistic human exposure to greenspace in East China while underestimating in West China. We further found that, in China, more recently urbanized areas have much better greenspace exposure than older urban areas. Our study provides a spatially explicit greenspace exposure metric for discovering multi-scale greenspace exposure difference, which will enhance governments' capacity to quantify environmental justice, detect vulnerable greenspace exposure risk hotspots, prioritize greenspace management at the supra-city scale, and monitor the balance between greenspace supply and demand. [ABSTRACT FROM AUTHOR]

• Plant iWUE presented a non-linear increase in the last century in Sothern China. • The annual rate of change of iWUE in Southern China showed an S-curve pattern. • Multiple atmospheric factors jointly affected iWUE in subtropical and tropical forests. Intrinsic water-use efficiency (iWUE) is a key physiological trait; however, the spatiotemporal variation in iWUE and which factors affect iWUE in the tropics and subtropics are poorly known. We determined the temporal (1920-2010) and spatial patterns of iWUE using leaf carbon-isotopic composition (δ13C) of 1,811 herbarium specimens and associated these patterns with environmental factors across biomes in southern China. We found that iWUE increased by 15.7 μmol mol−1 in the entire studied area from 1920 to 2010. The iWUE declined from west to east in southern China, with higher values concentrated in the southwest. Rising CO 2 concentrations ([CO 2 ]), N deposition, increases in mean annual temperature (MAT) and vapor pressure deficit (VPD), and changes in temperature seasonality (TS) contributed to the spatiotemporal changes in iWUE. Our results confirm that, in addition to a continuous increase in iWUE has, the rate of change of iWUE decreased in southern China in the later years. Multiple atmospheric factors jointly determine the changes in both iWUE and the rate of change of iWUE in the studied regions. [ABSTRACT FROM AUTHOR]