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Lung cancer remains the primary cause of death globally. Studies have increasingly explored the role of greenspace in mitigating lung cancer risks, yet research gaps persist. First, while the direct spatial effect of greenspace has received attention, its potential spillover effects, driven by human mobility and air pollution dispersion, remain underexamined. Second, despite prevalent assertions of greenspace as an air purifier, the extent to which it moderates the air pollution-lung cancer association has yet to be fully understood. Third, the evaluation of greenspace's effects, predominately analyzed linearly a priori , demands exploration into their potential nonlinearity. We utilize three-year lung cancer datasets from 228 counties in China, to investigate the spatial, moderating, and threshold effects of greenspaces on lung cancer incidence in relation to air pollution. Employing spatial econometric and threshold models, our findings indicate that greenspace reduces lung cancer incidence in both local and neighboring counties. We also observe a diminution in the detrimental impact of air pollution on lung cancer incidence in areas with higher greenspace, especially when the Normalized Difference Vegetation Index surpasses a given threshold. These insights contribute to an enhanced understanding of greenspace's role in lung cancer prevention and could inform policies on greenspace expansion prioritization. • Exposure to greenspaces can effectively mitigate the risk of lung cancer in both local and neighboring regions. • Greenspace can moderate the PM 2.5 -lung cancer association, especially when the NDVI surpasses a specific threshold. • The greenspace-related interventions aimed at enhancing lung cancer resilience at the regional level should be implemented. • The critical value of greenspace could be regarded as the essential requirement for regional urban planning policies. [ABSTRACT FROM AUTHOR]

As a component of both urban transport infrastructures and green spaces, urban greenways play a vital role in connecting urban public spaces, promoting active travel, and facilitating population-level health outcomes. Recently, there has been considerable interest in illustrating the determinants of greenway use in various contexts. Nevertheless, most studies have failed to identify the different aspects of greenway use. Meanwhile, the potential significance of residential neighborhood environments in utilizing greenways has largely been overlooked. In this study, we analyzed data collected from 1020 residents living around the East Lake Greenway in Wuhan, China, to discern three aspects of greenway use: frequency, time, and intensity. In addition, we investigated the moderate effect of neighborhood environmental characteristics on the association between greenway proximity and different aspects of use. After controlling for covariates, multi-level regression models showed that greenway proximity and neighborhood environmental characteristics were significantly associated with greenway use, while the specific associations varied across different aspects of greenway use. Furthermore, proportion of residential land, floor area ratio, and street connectivity moderated the relationship between greenway proximity and greenway use. In summary, the findings of this study contributed to the planning and management of greenways in high-density cities. • Among one of the first studies that distinguished different aspects of greenway use (e.g., frequency, time, and intensity). • We extended the influence of residential neighborhood environment on greenway use. • We investigated the moderate effect of neighborhood characteristics on the association between greenway proximity and use. [ABSTRACT FROM AUTHOR]

• Soil water content could be measured accurately at a hectometer scale using CRNS. • Temporally variable extent of CRNS footprint was identified. • Relative contribution of land uses to the signals was less affected by the types than the positions. • Occasional sampling in the dry season is a recommended strategy. Cosmic-ray neutron sensing (CRNS) is one of the few techniques that can directly acquire information about the temporal dynamics of soil water content (SWC) at a hectometer scale. The performance of CRNS depends on the climate, soil and conditions of the underlying surface. The region of red soil in China is characterized by heterogeneous land uses (combination of upland and paddy fields), distinct dry-wet periods and low contents of soil organic carbon. The applicability of CRNS has not yet been evaluated under the subtropical hydroclimatic conditions of this region. We therefore compared spatially averaged SWC measured using CRNS with point-scale data measured using time domain reflectometry (TDR) at five locations and oven-dried soil samples collected at 27 locations across the CRNS footprint in an agricultural ecosystem of the red-soil region between March 2019 and February 2020. The footprint of CRNS varied with time. The horizontal radius of CRNS varied between 175 m in July and 215 m in October, with a mean of 194 m, and the measuring depth varied between 16 cm in March and 23 cm in August, with a mean of 19 cm. The relative contribution of rainfed cropland, citrus land and paddy fields were 86.7, 10.7 and 2.6%, respectively. The differences of the relative contribution among land uses were determined by the distance to the sensor and the area, which were less affected by the types of land use. The neutron count rate (N 0 , counts/h) was weakly temporally variable, with a mean coefficient of variation of 3%. The influence of its variation on the accuracy of CRNS, however, should not be ignored. Both the timing and frequency of sampling affected the calculation of N 0. Occasional sampling in the dry season is a recommended strategy to acquire an accurate N 0 of a region. CRNS performed well for determining the dynamics of spatially averaged SWC in heterogeneous landscapes. More specifically, the accuracy of CRNS was comparable with those using the oven-drying method, with R 2, root mean square error and Nash-Sutcliffe model efficiency coefficient of 0.86, 0.026 cm3/cm3 and 0.81, respectively. This study evaluated the applicability of CRNS in a region with complex climatic, hydrological and underlying-surface conditions. These results are useful for developing a reasonable sampling strategy for acquiring an accurate N 0 and calibrating the CRNS. Future studies, however, should focus on the application of the CRNS technique to resolve the eco-environmental issues of the region. [ABSTRACT FROM AUTHOR]

Aim: Species–area relationships (SAR) are widely utilized for estimating the species richness and its spatial turnover across various scales. Despite the prevalent characterization of SAR using the power law in many microbial community studies, its efficacy remains unvalidated. This study aims to characterize the microbial SAR and its mechanisms in alpine grassland soils on the Qinghai‐Tibet Plateau (QTP). Location: Qinghai‐Tibet Plateau, China. Time Period: August 2014. Major Taxa Studied: Soil bacteria. Methods: Soil samples were collected from five alpine grassland sites on the QTP. Employing a nested sampling strategy at each site, soil samples were collected in plot sizes ranging from 0.5 × 0.5 m2 to 2048 × 2048 m2. Soil bacterial communities were analysed by sequencing 16S ribosomal RNA gene amplicons using an Illumina MiSeq. Results: The bacterial SAR exhibited a logarithmic power law (R2: 0.952–0.999), outperforming the power law (R2: 0.701–0.852). Consequently, the most widely adopted power law led to an overestimation of species richness by up to 15.07% in areas >256 × 256 m2, and the regional maximum theoretical richness based on Chao1 by up to 9.88%. Mechanistically, the passive sampling hypothesis was refuted through the rarefied species richness analysis, and the disproportionate effect hypothesis was rejected based on analyses of the effective numbers of species number conversions for the probability of interspecific encounters (SPIE). Notably, Pearson and multiple linear regression analyses indicated that the spatial turnover of bacterial richness was determined by the environmental heterogeneity (R2: 0.855–0.999), rather or better than environmental variables themselves, supporting the 'environment heterogeneity hypothesis'. Main Conclusions: Soil bacterial SAR in alpine grasslands exhibited a logarithmic power relationship. Spatial turnover was primarily governed by the environmental heterogeneity. In contrast, the traditional power law leads to an overestimation of soil bacterial diversity at the regional scale. [ABSTRACT FROM AUTHOR]

The complexity and uncertainty of pore structures, hinder the understanding of the water infiltration process along a soil profile. In this study, soil pore structures quantified by X-ray computed tomography (CT) scanning and infiltration processes traced using stable hydrogen and oxygen isotopes were lin k ed under three land uses (forestland, citrus land, and rainfed cropland) in the red soil region of southern China. Our results showed that 95% of the soil pore diameters in the surface layer (0–20 cm) in forestland, citrus land, and rainfed cropland were concentrated in the ranges of 0.05–2.46, 0.05–2.24 and 0.05–1.04 mm, respectively. Rainfed cropland had the most soil micropores, along with a high porosity and poor connectivity, while there were more large, well-connected tubular pore channels in the forestland and citrus land. Hydrogen and oxygen stable isotopes were effective in tracing soil water infiltration processes under saturated and near-saturated conditions. The soil infiltration depths of citrus land, forestland, and rainfed cropland were 45, 40, and 25 cm, with "new water" volumes of 37.2, 26.4, and 22.3 mm, respectively. CT-based porosity and the soil texture were considered crucial indicators in the evaluation of the exchange between "old water" and "new water" during infiltration processes. More specifically, the soil structure of the limiting layer not only controlled the infiltration rate but also played an extremely important role in the infiltration mechanism, reflected by the different ratios of "new water". The soil pore characteristics mainly affected soil water transport, while other soil properties played more important roles in soil water retention. • Land use affected the profile distribution of soil pore characteristics. • More information came from the stable isotope abundance of soil water than its contents. • The exchange ratio of "new water" and "old water" was obtained by stable isotopes. • Soils with well-connected structures had a higher proportion of "new water". • The pore structure of the limiting layer controlled the infiltration rate and mechanism. [ABSTRACT FROM AUTHOR]

• Non-linear patterns of microbial N genes occurred along precipitation gradient. • Breaking points were clearly related to certain soil types. • Attribution of different environmental factors varied by ecosystem. Despite the importance of microorganisms in soil nitrogen (N) cycling, studies on spatial patterns of microbial N-cycling gene abundances in temperate grasslands are still lacking, whose productivity is limited by N. Here, we investigated N functional genes in soil microorganisms from 60 sites in temperate grasslands across 1661 km in Inner Mongolia, China. Abundances of all N functional genes and 16S rDNA tended to decrease from northeast to southwest, consistent with the changing tend of precipitation but contrary to that of temperature. Non-linear saturation curves dominated patterns for abundances of most N functional genes and 16S rDNA along precipitation as they increased with the rising precipitation when <288–343 mm, but remained stable after these breaking points. Interestingly, these breaking points were clearly related to certain soil types, e.g. nifH did not change with precipitation in Chernozems and Gleysols, but increased with it in other soil types. Non-linear saturation patterns were also observed for most N functional gene and 16S rDNA abundances with temperature and soil total organic carbon. In contrast, no consistent spatial pattern for ratios of N functional genes: 16S rDNA was observed, which varied greatly by different N functional genes. Moreover, decay relationships were discovered for the abundance-based matrix of N functional genes over geographic distance. From the temperate meadows to typical steppes and to temperate desert steppes, the influence of relatively long-term environmental variables increased, but that of short-term ones decreased. Overall, we revealed non-linear patterns of N functional gene abundances along precipitation with a clear relationship with soil type, and discovered that attributions of geographic distance, plant community, historical-contingency and contemporary-disturbance to N functional gene community similarity decay were ecosystem–dependent. [ABSTRACT FROM AUTHOR]