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ABSTRACT Aim Location Time Period Methods Major Taxa Studies Results Main Conclusions Given that microbial communities normally comprise generalist and specialist species, there have been limited efforts to estimate the contribution of these sub‐communities to bacterial biogeography regarding ecological assembly processes and nestedness structure. To resolve this gap, we studied the spatial distribution of bacterioplankton communities and their generalist and specialist sub‐communities, as well as the underlying assembly processes.Six lakes span three climate zones in northern China.September 2021.By separately analysing the generalist and specialist sub‐communities from the whole communities, we investigated the relationships between sub‐communities and the entire communities in terms of distance‐decay pattern, nestedness, and assembly processes. As such, we assessed the contribution of generalist and specialist sub‐communities to the biogeographic patterns of the whole communities.Bacterial community.Generalist sub‐communities were more diverse but less abundant than specialist sub‐communities. In line with the whole communities, both types of sub‐communities exhibited distance‐decay relationships at the regional scale, with the slope of specialists being steeper than that of generalists. Additionally, generalist sub‐communities and whole communities also exhibited similar nestedness patterns, in which assemblages from saline water were the subset of those from freshwater. In terms of assembly processes, generalist sub‐communities and whole communities were strongly regulated by homogeneous selection, whereas specialist sub‐communities were mainly shaped by dispersal limitation. More importantly, there was a transition from stochastic to deterministic assembly processes for generalist sub‐communities and whole communities and generalist sub‐communities with increasing total dissolved solids.Relative to the specialists, the assembly processes and nestedness pattern were more altered if the generalists were absent, which implies the higher contribution of generalist sub‐communities on the biogeography of whole communities at the regional scale. [ABSTRACT FROM AUTHOR]

Soil hydraulic parameters are a key input for predicting soil water retention curves and water flow. The van Genuchten model is widely used to fit the van Genuchten hydraulic parameters including residual water content, saturated water content, a fitting parameter related to the inverse of the air entry pressure, and the shape parameter. This study aimed to show the interrelations of the soil hydraulic parameters on a large scale with both the inherent soil properties and the genetic type. The measured van Genuchten parameters originated from soil water retention curves determined in 100 pedons at 4 depths corresponding to the main soil diagnostic horizons. The results showed that the effect of soil texture on the van Genuchten hydraulic parameters was greater than that of the genetic soil type. The van Genuchten hydraulic parameters were in general significantly higher in fine-textured than coarse-textured soils. The vertical distribution of the hydraulic parameters was more discontinuous in fine-than in coarse-textured soils. The van Genuchten equation fits well to measured soil water retention (R2 > 0.885) and thereby can predict the soil water retention curve for a variety of soils with acceptable uncertainty and improve soil water conservation on a large regional scale. [ABSTRACT FROM AUTHOR]

The near-surface air temperature (${{T}_{air}}$) is a principal variable describing energy exchange and water circulation between the land surface and the atmospheric environment. The estimation of ${{T}_{air}}$ by satellite land surface temperature (LST) is challenging due to the variable magnitude of the difference between ${{T}_{air}}$ and LST in both space and time, as well as the restriction of estimated ${{T}_{air}}$ to clear-sky conditions because of the penetration of infrared wavelengths. Moreover, the estimation suffers from low temporal resolution and primarily focuses on daily minimum, maximum, and two instantaneous ${{T}_{air}}$ per day. This study proposes a method for estimating all-sky gridded diurnal ${{T}_{air}}$ at regional scale from FY-4B/AGRI measurements. The multiscale geographically weighted regression model was investigated to establish the dynamic relationships between ground station observed ${{T}_{air}}$ and satellite LST under clear-sky conditions by employing different spatial values for each explanatory variable in localized regressions. A moving window loop based multiple linear regression was employed to establish the relationship between satellite-derived clear-sky ${{T}_{air}}$ and other variables to extrapolate ${{T}_{air}}$ in cloudy-sky pixels. The results showed that the proposed method captures the trend of ${{T}_{air}}$ variations well in hourly profiles with R values greater than 0.95. RMSE was 1.75 °C, 1.38 °C, 1.95 °C, and 2.19 °C in April, July, October, and January, respectively. The demonstration of heatwave monitoring showed that satellite-estimated ${{T}_{air}}$ provide an excellent representation of the spatial and temporal evolution of the heatwave.

Abstract Effective geographical origin discrimination of Chinese rice requires a large database of samples to ensure sufficient data for origin verification at a regional scale. In this study, environmental similarity was used to establish a spatial database of rice nutrient element, and then the validity of the database was verified using the back propagation artificial neural networks modeling (BPNN). The spatial distribution model of 14 rice nutrient element (Al, Ba, Ca, Cu, Cr, Fe, K, Mg, Mn, Mo, Na, Ni, Rb, and Zn) on regional scale was built using an environmental similarity method for the first time. Elemental concentrations of 692 samples were used to build a simulated geographical origin prediction model for northeastern (N‐E), middle to lower Yangtze River plain (Y‐R), southwestern (S‐W), and southeastern (S‐E) in China. The results indicated that the performance of the environmental similarity model for these four growing regions was S‐W > N‐E > S‐E > Y‐R based on the lowest ranking root mean square error (RMSE) for each region. For example, the RMSEs of Zn in S‐W, N‐E, S‐E, and Y‐R regions were 2.0, 2.4, 2.7, and 3.7 mg/kg, respectively. A case study on the traceability of Japonica rice was shown that Japonica rice could be discriminated with higher origin accuracy using a simulated database (91.8%) than by the actual database (87.0%) using the BPNN model. This indicates that a simulated rice element database could improve the accuracy of geographical origin discrimination for Chinese rice and potentially be applied to other large national‐scale crop datasets.

[Objective] Soil and water conservation is important in protecting and improving the ecological environment, which plays an important role for the sustainable development of ecosystems. [Methods] While the study of the soil and water conservation effectiveness in regional scale provide an effective theoretical basis for soil and water conservation. [Results] We supposed an estimation method for the regional-scale soil and water conservation rates by remote sensing based on the RUSLE (revised universal soil loss equation), and estimated its the spatial pattern in Shanxi Province.The results showed that the soil erosion in Shanxi Province is dominated by moderate erosion, with an area of about 49 545.68 km2, and the soil and water conservation rates is 68.38% in 2022, and the soil and water conservation rates accounted for the largest proportion in high level. The soil and water conservation rates of natural vegetation is higher than that of cropland, among which, the rates of forest is the highest at 84.37%. The soil and water conservation rates of the natural vegetation and cropland accounted for the largest proportion in high level with 48.11% and 46.46%, respectively. The rates is greatly affected by slopes, and showed a trend of significant decrease followed by gentle fluctuation. Compared with previous researches, the estimated spatial pattern of soil erosion in Shanxi Province were consistent with the existing data. And the estimated soil and water conservation rates was significantly correlated with the published targets. [Conclusion] The method of estimating soil and water conservation rates at the regional scale by remote sensing can provide an important theoretical and methodological basis for evaluating the effectiveness and impact of soil and water conservation ecological projects and other national large-scale ecological projects.

This study introduces a rapid simulation method for assessing seismic damage to building curtain walls at a regional scale. Although the results are approximate, this approach enables quick evaluations, making it an important instrument for emergency responses during disaster situations. This method’s independence from numerical models is a noteworthy advantage. Unlike conventional approaches, it eliminates the need for structural analysis models when evaluating the seismic capacities of curtain walls regionally. Creating reliable structural analysis models is both time-consuming and labor-intensive, primarily due to the detailed design information they require. In contrast, the presented method leverages the wind load capacities for which curtain walls are designed. It is based on the core premise that most curtain walls, primarily designed for wind resistance, possess wind load capacities that could serve as substitutes for their seismic capacities, even if they are not explicitly designed for such seismic loads. To assess the method’s effectiveness, it was applied to seismic damage assessments across regions experiencing varying wind intensities: weak, moderate, and strong. The results suggest the likelihood of curtain walls sustaining seismic damage in regions with weak wind could be five times higher than in regions with strong wind. This underscores the importance of seismic design considerations for curtain walls. Moreover, the findings closely match the actual seismic damage assessment data from a region with a moderate to strong wind intensity. [ABSTRACT FROM AUTHOR]

Temperature variation in the past periods can provide valuable insights into the characteristics and driving mechanisms of current global warming and future changes. Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are commonly used to as a temperature proxy to quantitatively reconstruct past temperature changes. However, it still remains unclear whether the relation between brGDGTs and temperature is influenced by other environmental factors, thereby affecting the accuracy of quantitative reconstructions. A comprehensive analysis of the relation between brGDGTs and temperature across various climate regions can greatly enhance the accuracy of reconstructing past temperature changes. Here, we investigate the distribution patterns of soil brGDGTs using 28 new topsoils collected from altitudes ranging from 2100 to 4000 m.a.s.l. in the Hengduan Mountains in the southeastern margin of the Tibetan Plateau (TP), compiled previously published soil brGDGT data in China. Our results reveal distinct distribution patterns of soil brGDGTs between humid and arid regions. Furthermore, we further investigated the correlation between brGDGT indices and various environmental factors from both altitudinal and regional scales. At the altitudinal scale, brGDGT indices exhibit a stronger correlation with mean annual air temperature (MAAT) in alkaline soils (pH > 7) than that in acidic soils (pH < 7). At the regional scale, this correlation is higher in alkaline soils than that in acidic soils as well and is stronger in humid soils (mean annual precipitation [MAP] > 800 mm) than that in semi‐humid and semi‐arid soil (400 < MAP < 800 mm) and arid soil (MAP < 400 mm). In addition, brGDGT‐inferred temperature is more affected by MAP in humid alkaline soils but less affected in humid acidic soils. Therefore, caution is needed to use suitable brGDGT index for palaeotemperature reconstructions in various climate regions. [ABSTRACT FROM AUTHOR]

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Plot-scale natural attenuation models provide valuable insights into localized pollutant behavior but struggle to account for regional-scale hydrological processes. Existing research has predominantly concentrated on single processes, lacking comprehensive models to describe the output flux of persistent organic pollutants (POPs) by transport and transformation from soil at a regional scale. To address this gap, a model was developed by combining natural attenuation processes (e.g., degradation, volatilization, plant uptake) with hydrological transport processes (e.g., leaching, water washout, sediment transport). The model was validated using data from a petrochemical area in China and compared with the previous model (mass balance and neural networks model) to assess pollutant output flux. Results indicated that water washout was the dominant output pathway from soil for both Phenanthrene (Phe) (94.67 %) and Benzo(a)pyrene (BaP) (98.33 %). Phe exhibited a broader output flux range (0–67.8 mg∙m−2∙a−1) compared to BaP (0–12.9 mg∙m−2∙a−1), due to its higher volatility and solubility. Performance evaluation through 10-fold cross-validation yielded coefficient of determination (R2) values greater than 0.7 and root mean square error (RMSE) below 3 %, outperforming the previous model. Sensitivity analysis revealed that the soil organic carbon mass fraction (foc) was the most influential parameter at both a plot and regional scale. This study fills a gap in environmental research by providing a comprehensive model for accurate estimates of POPs output fluxes from soil.

Heathlands are extensive systems often dominated by slow‐growing and long‐lived woody plants. These systems require longer‐term studies to capture if and how they are changing over time. In 2020, we resurveyed species richness and cover of vascular plant communities in 139 heathlands along the coastline of northern Fennoscandia, first surveyed during 1965–1975. The first survey included six heathland types, each with dominance – a cover of 25% or more – of the dwarf shrubs Calluna vulgaris, Kalmia procumbens, Betula nana, Vaccinium myrtillus and Empetrum nigrum. The two latter heathland types made up 29% and 48%, respectively, of all heathlands. In addition to the dominant dwarf shrubs giving their names to the heathland types, a few other species qualified as dominant. In the resurvey, all the heathland types had E. nigrum as the single dominant species, except for the heathland formerly dominated by B. nana. Most other species had low cover both at the time of the original survey and the resurvey. Also, the heathland types were species poor at the time of the original survey, with an average of eight vascular plant species per 4 m2 and were found equally species poor in the resurvey. Species richness differed between heathland types only at the time of the original survey, and the ratio of species exchange between the two surveys was negatively related to the original cover of E. nigrum. Here we provide a half‐century perspective on vegetation change, during which several heathland types in northern Fennoscandia have changed to Empetrum heathlands, reducing the diversity of heathland types across the Boreal to Arctic landscape. As a native plant, E. nigrum cannot be considered invasive, but its allelopathic capacity has likely already modified these heathland ecosystems and will continue to do so, reducing ecosystem multifunctionality across the region. [ABSTRACT FROM AUTHOR]

Understanding how habitat attributes (e.g., patch area and sizes, connectivity) control recruitment and how this is modified by processes operating at larger spatial scales is fundamental to understanding population sustainability and developing successful long‐term restoration strategies for marine foundation species—including for globally threatened reef‐forming oysters. In two experiments, we assessed the recruitment and energy reserves of oyster recruits onto remnant reefs of the oyster Saccostrea glomerata in estuaries spanning 550 km of coastline in southeastern Australia. In the first experiment, we determined whether recruitment of oysters to settlement plates in three estuaries was correlated with reef attributes within patches (distances to patch edges and surface elevation), whole‐patch attributes (shape and size of patches), and landscape attributes (connectivity). We also determined whether environmental factors (e.g., sedimentation and water temperature) explained the differences among recruitment plates. We also tested whether differences in energy reserves of recruits could explain the differences between two of the estuaries (one high‐ and one low‐sedimentation estuary). In the second experiment, across six estuaries (three with nominally high and three with nominally low sedimentation rates), we tested the hypothesis that, at the estuary scale, recruitment and survival were negatively correlated to sedimentation. Overall, total oyster recruitment varied mostly at the scale of estuaries rather than with reef attributes and was negatively correlated with sedimentation. Percentage recruit survival was, however, similar among estuaries, although energy reserves and condition of recruits were lower at a high‐ compared to a low‐sediment estuary. Within each estuary, total oyster recruitment increased with patch area and decreased with increasing tidal height. Our results showed that differences among estuaries have the largest influence on oyster recruitment and recruit health and this may be explained by environmental processes operating at the same scale. While survival was high across all estuaries, growth and reproduction of oysters on remnant reefs may be affected by sublethal effects on the health of recruits in high‐sediment estuaries. Thus, restoration programs should consider lethal and sublethal effects of whole‐estuary environmental processes when selecting sites and include environmental mitigation actions to maximize recruitment success. [ABSTRACT FROM AUTHOR]

In order to address the impact of nuclear accident on the atmospheric environment, an analysis method for the atmospheric diffusion characteristics of radionuclides at different scales was established, which was based on the regional scale weather prediction model weather research forecasting model ( WRF). Taking multiple nuclear power plants in the eastern region as the research object, the atmospheric diffusion distribution characteristics of radionuclides released from nuclear accident in the eastern region and in the nuclear power plant surrounding region were studied. The WRF model was used, which was driven by final reanalysis data (FNL) reanalysis meteorological data, combined with the Gaussian atmospheric diffusion model. The results show that the maximum atmospheric diffusion factor at the regional scale mainly distributes in the western region of the calculation area, and it shows a decreasing trend with increasing distance. The difference of the maximum atmospheric diffusion factor at distances of 500 m and 5 000 m is about one order of magnitude. The maximum atmospheric diffusion factor of nuclear power plant surrounding region scale is one order of magnitude lower than that of the regional scale. The difference of the maximum atmospheric diffusion factor at distances of 500 m and 5 000 m is about one order of magnitude for other nuclear power plants,except Qinshan Nuclear Power Plant. There are significant differences of the direction of the maximum atmospheric diffusion factor among different nuclear power plants due to the influence of meteorological conditions of the plant site. The atmospheric diffusion capacity in eastern coastal region is stronger than that in inland region, which is conducive to the atmospheric transport of radioactive radionuclides. [ABSTRACT FROM AUTHOR]

High‐quality urbanization and a healthy ecosystem are both the material basis for sustainable social development. However, the tie between terrestrial ecosystem health (TEH) and urbanization is still unclear. Therefore, we assessed the spatial and temporal dynamics of urbanization and TEH at 368 cities in China from 2000 to 2020, then explored their spatial interaction and driving mechanisms by spatial autocorrelation analysis and structural equation modeling. The results showed: (1) China's comprehensive urbanization index (UI) improved from 0.08 in 2000 to 0.10 in 2020, contributing by some national urban agglomerations such as Beijing‐Tianjin‐Hebei, Yangtze River Delta, and Pearl River Delta. (2) China's terrestrial ecosystem health index (EHI) also increased from 0.67 to 0.68. Ecosystem vigor improved significantly, while ecosystem organization and resilience both decreased. (3) EHI and UI appeared to be locally spatially dependent, and path dependence was presented at municipal scales. (4) At the national scale, urbanization positively relates to EHI, which was enhanced by social, economic, and topography factors. The dominant drivers on EHI varied among regions, and urbanization improved EHI in all regions except for the southwest. Our study demonstrated that urbanization would promote TEH by implementing high‐quality development and ecological management simultaneously, providing theoretical support for urban sustainable development and ecological management. [ABSTRACT FROM AUTHOR]

Ephemeral gully (EG) erosion is an important type of water erosion. Understanding the spatial distribution of EGs and other influencing factors at a regional scale is crucial for developing effective soil and water management strategies. Unfortunately, this area has not been sufficiently studied. The present study visually interpreted the EGs based on Google Earth images in 137 small watersheds uniformly distributed in the Loess Plateau, compared them with measured results, and analyzed the factors influencing EG formation and density using GeoDetector. The results showed that visually interpreting EGs from Google Earth images was suitable for EG regional studies. Out of the 137 small watersheds, 33.6% had EG occurrence with an average density of 3.41 km/km2. Rainfall (R) and slope gradient (S) were the primary factors influencing the formation of EGs, while the area proportion of sloping farmland (APSF) and soil erodibility (K) were the main factors affecting EG density. The interaction of dual factors had a greater influence compared to single factors, with the interaction between S and Normalized Difference Vegetation Index (NDVI) having the greatest impact on EG formation and the interaction between K and NDVI on EG density. Although natural forces significantly influence whether EGs can form in a specific area, human activities greatly affect the density of the gullies that develop. This underscores the importance of proper land management in controlling gully erosion. These findings could provide theoretical support for EG prediction models and a scientific basis for soil and water loss control strategies at the regional scale. [ABSTRACT FROM AUTHOR]

Land dissection density (LDD) provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections. A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters, soil erosion, and other related domains. Land dissection phenomena in China affects large areas with different morphological, pedological, and climatic characteristics. Prior studies have focused on the potential factors influencing the LDD at a watershed scale. However, these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national scale. LDD's spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be ascertained. This study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China's six first-order geomorphological regions (GR1∼GR6). The results yield the following findings: (1) LDD in China ranges from 0∼4.55 km/km2, which is larger in central and eastern regions than in other regions of China; (2) dominant factors and their dominant risk subcategories vary with each geomorphological region's primary internal and external forces; (3) the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors; relief degree of land surface (RDLS) is dominant in GR1, GR2, and GR5; the slope is dominant in GR6, soil type is dominant in GR3 and GR4, and lithology plays a critical role in the dominant interactions of GR3, GR4, and GR6; (4) the interactions between factors on LDD's spatial pattern have a more significant effect than individual factors. [ABSTRACT FROM AUTHOR]

Accurate, timely, and fine-resolution crop phenology is essential for determining the optimal timing of agronomic management practices supporting precision agriculture and food security. Synthetic Aperture Radar (SAR) methods, unaffected by cloud occlusion, have been widely applied in monitoring maize phenology. Nonetheless, their reliance on manual threshold settings, which depend on the user's expertise, limits their applicability. Furthermore, the neglect of SAR's potential for monitoring other phenological periods (e.g., seven-leaves date (V7), jointing date (JD), tassel date (TD), and milky date (MID)) hinders their robustness, particularly for regional-scale applications. To address these issues, this study used an adaptive dynamic threshold to evaluate the ability of the Sentinel-1 cross-polarization ratio (CR) in detecting the three-leaves date (V3), V7, JD, TD, MID, and maturity date (MD) of maize. We analyzed the effect of incidence angle, precipitation, and wind speed on Sentinel-1 features to identify the optimal feature for time series fitting. Then, we employed linear regression to determine the optimal threshold and developed an adaptive dynamic threshold for phenology detection. This approach effectively mitigated the speckle noise of Sentinel-1 and minimized artificial interference caused by customary conventional thresholds. Finally, we mapped phenology across 8.3 million ha in Heilongjiang Province. The results indicated that the approach has a higher ability to detect JD (RMSE = 11.10 d), MID (RMSE = 10.31 d), and MD (RMSE = 9.41 d) than that of V3 (RMSE = 32.07 d), V7 (RMSE = 56.37 d), and TD (RMSE = 43.33 d) in Sentinel-1. Compared with Sentinel-2, the average RMSE of JD, MID, and MD decreased by 4.14%, 35.28%, and 26.48%. Moreover, when compared to different thresholds, the adaptive dynamic threshold can quickly determine the optimal threshold for detecting each phenological stage. CR is least affected by incident angle, precipitation, and wind speed, effectively suppressing noise to reflect phenological development better. This approach supports the rapid and feasible mapping of maize phenology across broad spatial regions with a few samples. [ABSTRACT FROM AUTHOR]

This study presents a reconstruction of basin scale long-term annual surface mass balance (SMB) estimates for 91 glaciers (≥ 1 km2) of Chandra basin in Western Himalayas from 1989 to 2020. The presented approach requires three inputs: annual Equilibrium Line Altitude (ELA), long-term average mass balance, and an estimate of mass balance gradient across ELA for a representative glacier. Here, the annual ELA for each study glaciers is estimated using freely available optical remote sensing images. The average mass balance of the study region and mass balance gradient of a representative glacier are obtained from satellite-based geodetic method and available field estimates, respectively. The obtained results indicate that the average ELA of the basin increased at a rate of 4.22 m asl year−1 during study period. The reconstructed SMB estimates indicate that the glaciers in the Chandra basin were in near-steady state between 1989 and 1999; then, lost mass at an accelerated rate. The basin-wide average SMB for the study period is estimated to be − 0.47 ± 0.50 m w.e. year−1. Overall, Chandra basin lost 13.72 ± 12.5 m w.e (7.3 ± 6.5 Gt) ice mass between 1989 and 2020. Though the estimates have relatively high uncertainty compared to other available studies, the results are encouraging considering the simplicity and parsimonious nature of the approach. Furthermore, a sensitivity analysis shows that reduction in overall uncertainty can be achieved using average mass balance estimates characterized by less uncertainty. Encouraging results suggest that the adopted approach can be extended to other regions. However, detailed studies with proper validation are needed in other regions of Himalayas to ascertain the use of this approach on the unmonitored glaciers of Himalayas to reconstruct time series of annual SMB. [ABSTRACT FROM AUTHOR]

Dams are increasingly disrupting natural river systems, yet studies investigating their impact on microbial communities at regional scale are limited. Given the indispensable role of bacterioplankton in aquatic ecosystems, 16S rRNA gene sequencing was performed to explore how these communities respond to dam-influenced environmental changes at the regional scale in the Shaying River Basin. Our findings revealed that cascade dams create distinct environments, shaping bacterioplankton communities near the dams differently from those in natural rivers. In the upstream of the cascade dams, water quality was superior, while bacterioplankton community structure was simple with weak community interactions. In the midstream, nutrient and heavy metal content were increased, making bacterioplankton structures more susceptible to environmental changes. In the downstream of the cascade dams, water quality had a significant impact on the community and the bacterioplankton structures were highly complex. Additionally, environmental variables significantly influenced bacterioplankton functional groups. However, the response to these factors, as well as the interplay between functional and taxonomic diversity, varied markedly depending on the specific region of the cascade dams. We here delved into the effects of cascade dams on the taxonomic diversity and functional groups of bacterioplankton to provide a theoretical basis for segmentally regulating these dams. [ABSTRACT FROM AUTHOR]

Geochemical tracers have the potential to provide valuable insights for constructing conceptual models of groundwater flow, especially in complex geological contexts. Nevertheless, the reliability of tracer interpretation hinges on its integration into a robust geological framework. In our research, we concentrated on delineating the groundwater flow dynamics in the Innisfil Creek watershed, located in Ontario, Canada. We amalgamated extensive hydrogeological data derived from a comprehensive 3D geological model with the analysis of 61 groundwater samples, encompassing major ions, stable water isotopes, tritium, and radiocarbon. By seamlessly incorporating regional physiographic characteristics, flow pathways, and confinement attributes, we bolstered the efficiency of these tracers, resulting in several notable findings. Firstly, we identified prominent recharge and discharge zones within the watershed. Secondly, we observed the coexistence of relatively shallow and fast-flowing paths with deeper, slower-flowing channels, responsible for transporting groundwater from ancient glacial events. Thirdly, we determined that cation exchange stands as the predominant mechanism governing the geochemical evolution of contemporary water as it migrates toward confined aquifers situated at the base of the Quaternary sequence. Fourthly, we provided evidence of the mixing of modern, low-mineralized water originating from unconfined aquifer units with deep, highly mineralized water within soil–bedrock interface aquifers. These findings not only contribute significantly to the development a conceptual flow model for the sustainable management of groundwater in the Innisfil watershed, but also offer practical insights that hold relevance for analogous geological complexities encountered in other regions. [ABSTRACT FROM AUTHOR]

This work is based on an analysis of the spatial trends and drivers of soil C, N, and P contents and their stocks in relation to latitude, longitude, and altitude. For this purpose, the coniferous forests of Qinghai spruce (Picea crassifolia (Pc)) and Qilian juniper (Juniperus przewalskii (Jp)) within the Qilian Mountains in northwest China were selected as the objects of research. It was found that at the regional scale, the C and N contents in soil from the Pc forests were 1.34 and 1.17 folds higher than those of the Jp forests, respectively, whereas the P content was 0.92 fold lower than that of the Jp forests. Interestingly, the stock of soil C and N in the two forests was consistent, indicating an equivalent role of both in maintaining the regional C and N stocks. Secondly, the soil C and N stocks of Jp were the highest at a low altitude (< 2800 m), which indicated that the Jp forest trees retained high amounts of C and N at an altitude < 2800 m. In addition, the stocks of soil C and N correlated negatively with the latitude and positively with the longitude (P < 0.05). A partial redundancy analysis and random forests regression models showed that the stocks of soil C, N, and P were primarily controlled by the soil properties, particularly the bulk density and nutrient contents. Overall, these results provide insights into the effects of soil and terrain factors on soil C, N, and P stock, thereby providing a foundation for targeted forest conservation and rehabilitation in the Qilian Mountains in the future. [ABSTRACT FROM AUTHOR]

Grazing exclusion (GE) and rest grazing (RG) are important management systems for the restoration of degraded grassland ecosystems. In order to evaluate the effects and mechanisms of different grazing management systems on the scale dependency of species diversity, plant community indices and soil variables were determined in 32 plots in the Qilian Mountains in Gansu Province. The results show that diversity effects and their regulating mechanisms had space-scale dependence under different grazing management systems. The species richness and species diversity indices of RG grassland were significantly higher than those of GE at the regional scale. Species richness for RG and GE plots was 128 and 98, respectively, and the Shannon–Wiener and Simpson indices for RG and GE plots were 2.26 and 2.16, and 0.85 and 0.83, respectively. Additionally, three grazing management systems had a significant effect on species richness in mountain meadows, but different management systems had significantly different effects on species diversity indices in mountain meadows and temperate steppes. Meanwhile, soil variables only influenced species diversity at the regional scale. Most of the plant and soil variables at each scale had positive effects on species diversity. However, a negative correlation was seen between biodiversity and species coverage, mean plant height, soil porosity (SP) and bulk density (BD) under the two contrasting grazing management systems. In conclusion, choosing RG at the regional scale and selecting grazing management systems according to different grassland types at the local scale can help to restore degraded grassland vegetation. [ABSTRACT FROM AUTHOR]

Ephemeral gully (EG) erosion is an important type of water erosion. Understanding the spatial distribution of EGs and other influencing factors at a regional scale is crucial for developing effective soil and water management strategies. Unfortunately, this area has not been sufficiently studied. The present study visually interpreted the EGs based on Google Earth images in 137 small watersheds uniformly distributed in the Loess Plateau, compared them with measured results, and analyzed the factors influencing EG formation and density using GeoDetector. The results showed that visually interpreting EGs from Google Earth images was suitable for EG regional studies. Out of the 137 small watersheds, 33.6% had EG occurrence with an average density of 3.41 km/km2. Rainfall (R) and slope gradient (S) were the primary factors influencing the formation of EGs, while the area proportion of sloping farmland (APSF) and soil erodibility (K) were the main factors affecting EG density. The interaction of dual factors had a greater influence compared to single factors, with the interaction between S and Normalized Difference Vegetation Index (NDVI) having the greatest impact on EG formation and the interaction between K and NDVI on EG density. Although natural forces significantly influence whether EGs can form in a specific area, human activities greatly affect the density of the gullies that develop. This underscores the importance of proper land management in controlling gully erosion. These findings could provide theoretical support for EG prediction models and a scientific basis for soil and water loss control strategies at the regional scale.

AbstractThe peak roof drift ratio is one of the most important engineering parameters to describe the expected seismic damage in a building. A predictive model of the drift ratio was developed using a machine learning approach (Gaussian process regression model) on a dataset of approximately 11,800 records from 34 monitored buildings in Japan. Four predictors for ground motion and three predictors for building vulnerability are used in the machine-learning modelling. The residual analysis shows a reduction of 50% compared to the state of the art. The Gaussian process regression model is applied in a second analysis on an original dataset of approximately 4,500 records for 127 monitored buildings in Italy. A satisfactory comparison emerges by comparing the drift ratio prediction map with the observed damage pattern produced by satellite imagery for a test site in central Italy after the 2009 earthquake. The drift ratio map plays an important role in the simulation of an earthquake scenario at regional scale, which is needed by Civil Protection for emergency planning and management activities.

Mobility as a service (MaaS) is a promising lever to achieve a more sustainable, co-modal, and flexible urban system for daily mobility. MaaS is crucial to addressing the challenges imposed by hyper-urbanization, social changes, saturation of public soil with private motor vehicles, and local and global environmental issues. The aim of this paper is to analyse important characteristics of MaaS, namely public governance, regional scale, and high level of development. A total of 13 MaaS initiatives implemented in some European cities were compared using multi-criteria analysis. The results show that, although the MaaS implementation process is faster for private initiatives, public governance is shown to be the most appropriate entity to develop stable MaaS services, as it can enable the achievement of a higher level of integration, coupled with a high rate of service adoption, as well as reduce market entry barriers for service providers while also guaranteeing fair competition, and consequently fostering a higher level of service provided to users. The regional coverage of MaaS is crucial to ensure service provision to a wider population, living in both metropolitan and rural areas. These important features are included in the BIPforMaaS project run by the Italian region of Piedmont, described in detail in this paper. [ABSTRACT FROM AUTHOR]

To identify the impact of carbon emissions in the construction industry on the society and economy at a regional scale is of great significance for the sustainable development of the construction industry. Taking Shandong, China, as an example, this study uses a process-based carbon emission assessment method to calculate the carbon emissions of the construction industry in Shandong from 2010 to 2020. Based on specific situations at different phases, ten major factors affecting the society and economy have been analyzed and identified. Then, the Seemingly Uncorrelated Regression (SUR) model was used to analyze carbon emissions and economic and social factors at each stage. The results show the following: (1) The overall carbon emissions of the construction industry in Shandong are on an increasing trend, the carbon emission intensity is on a decreasing trend, and the material production and operation stages are the main source of carbon emissions; (2) There is a significant relationship between carbon emissions in the construction phase and all influencing factors, so it should be the main phase for macro-regulation; (3) Unlike in the Ordinary Least Square (OLS) model, the error terms of the gross output value of the construction industry and the total turnover of the main building materials equations are independent; however, there is an interaction between the error terms of the remaining equations. The results provide a theoretical reference for governmental departments to set up environmental targets and make policy regulations. [ABSTRACT FROM AUTHOR]

Vegetation restoration in ecologically fragile areas has a significant carbon sequestration (CS) effect. However, it is usually difficult to achieve quantitative assessment at the regional scale for this part of human activity intervention. The Chinese government's ex‐situ poverty alleviation and relocation (EPAR) project has relocated approximately 10 million people from areas with a fragile ecological environment to urban centralized resettlement, which is a typical case of weakened environmental intervention by human activities (Guizhou Province accounting for approximately 20% of the total relocated population in China). The CS model of vegetation photosynthesis and spatial analysis of geographic information were used to quantify the contribution of human activities to the natural restoration of vegetation CS, based on the data of net primary productivity (NPP) of vegetation from 2000 to 2020. The results show that the implementation of the EPAR project acts as an external force to drive vegetation restoration and CS, which increases the slope of the carbon density change trend (from k = 30.9 to k = 57.41), resulting in an overall carbon density increase of 26.51 tCkm−2. The regional spatial analysis showed that the correlation coefficients between carbon density and relocation intensity in the 5‐year and 10‐year change were r = 0.976 (p < 0.01) and r = 0.949 (p < 0.05), respectively, indicating a significant positive correlation. Based on this, the CS contribution of vegetation in 84 districts in Guizhou Province that implemented EPAR projects was calculated, showing that 79 districts contributed positively, accounting for 94%. The average contribution of CS by vegetation restoration in each district was 0.0556 Tg, and offset CO2 emissions were 0.2059 Tg. The other five districts with a negative contribution to CS were distributed in regions with relatively stable ecosystems and mature forests. This shows that human intervention in the environment changes more significantly in fragile ecological areas. [ABSTRACT FROM AUTHOR]

The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture, spatial resolution, and multiple parameter categories, which is challenging to achieve using satellite remote sensing. Considering the convenient, facilitative, and flexible characteristics of UAV (unmanned air vehicle) remote sensing technology, this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data. Using professional software, including Context Capture, ENVI, and ArcGIS, a 3D(three-dimensional) campus model, a digital orthophotomap, andmultispectral remote sensing map drawing are realized, and the geometric accuracy of typical feature selection is evaluated. Based on a quantitative remote sensing model, the campus ecological environment assessment is performed from the perspectives of vegetation and water body. The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. [ABSTRACT FROM AUTHOR]

Spaceborne L-band data have the potential to monitor flooded and irrigated areas. However, further studies are needed to assess in real cases the impact of flood-irrigated crops on soil moisture and ocean salinity (SMOS) and soil moisture active passive (SMAP) surface soil moisture (SSM) data. This letter demonstrates the ability of SMOS/SMAP SSM retrievals to quantify the fraction of flood-irrigated areas at the seasonal scale and at a 25-km resolution in the Telangana State in southern India. Over irrigated areas, both SMOS level 3 (L3) SSM and SMAP L3 enhanced SSM products present a bimodal annual cycle, with a peak of SSM during the monsoon (wet) season corresponding to rainfall and irrigation, and a peak during the dry season due to irrigation activities solely. The second peak is absent or has a very small amplitude in areas where rice represents a small fraction (typically below 5%–10%). More importantly, the amplitude of the second SSM peak is significantly correlated with the rice cover fraction within $25\times25$ km2 pixels ($R = 0.81$ for SMOS and 0.77 for SMAP), showing its potential to assess crop fraction and hence the water used for irrigation. The SMOS/SMAP L3 SSM peak during the dry period occurs several months before the harvest, constituting an indicator for rice stocks at the end of the season. However, the irrigation signature is absent from the SMAP level 4 SSM product derived from the assimilation of SMAP brightness temperatures (Tbs) in a land surface model, which indicates that the data assimilation scheme is inefficient to restitute irrigation information. [ABSTRACT FROM AUTHOR]

Background. The Nechako River Basin (NRB) is a large, regulated basin in north-central British Columbia, Canada that has been impacted by numerous landscape disturbances, including a severe wildfire in 2018. Aims. The aims of this study were to quantify the post-wildfire temporal and spatial extent of contamination by polycyclic aromatic hydrocarbons (PAHs) of both soils and riverine sediments, and to identify the primary sources of PAHs in the watershed. Methods. Soil samples were collected at burned and unburned sites in 2018 and at the burned sites in 2020 and 2021. Sediment samples were collected at three tributaries impacted by wildfire and three Nechako River mainstem (i.e. main channel) sites from 2018 to 2021. Samples were analysed for parent PAHs. Key results. PAH concentrations decreased in soil samples from 2018 to 2021 but are not below the concentrations found in unburned samples. Tributary sediment samples showed higher concentrations immediately post-fire relative to the mainstem Nechako River, but in the years since, that trend has reversed. Conclusions. PAHs persist in terrestrial and aquatic environments for years following wildfire, but at concentrations below various quality guidelines. PAHs were primarily derived from the wildfires, with some mixed sources at the downstream sites. Implications. Wildfires are an important source of environmental contamination of terrestrial and aquatic environments. [ABSTRACT FROM AUTHOR]

While it is well accepted that climate change and growing water needs affect long-term sustainable water resources management, performing accurate simulations of water cycle and energy balance dynamics at regional scale remains a challenging task.Traditional Soil-Vegetation-Atmosphere-Transfer (SVAT) models are used for numerical surface water and energy simulations. These models, by conception, do not account for the groundwater lower boundary that permits a full hydrosystem representation. Conversely, while addressing important features such as subsurface heterogeneity and river–aquifer exchanges, groundwater models often integrate overly simplified upper boundary conditions ignoring soil heating and the impacts of vegetation processes on radiation fluxes and root-zone uptakes. In this paper, one of the first attempts to jointly model water and energy fluxes with a special focus on both surface and groundwater at the regional scale is proposed on the Seine hydrosystem (78,650 km$^{2}$), which overlays one of the main multi-aquifer systems of Europe.This study couples the SVAT model ORCHIDEE and the process-based hydrological–hydrogeological model CaWaQS, which describes water fluxes, via a one-way coupling approach from ORCHIDEE toward CaWaQS based on the blueprint published by [de Marsily et al., 1978]. An original transport library based on the resolution of the diffusion/advection transport equation was developed in order to simulate heat transfer in both 1D-river networks and pseudo-3D aquifer systems. In addition, an analytical solution is used to simulate heat transport through aquitards and streambeds. Simulated ORCHIDEE surface water and energy fluxes feed fast surface runoff and slow recharge respectively and then is used as CaWaQS forcings to compute river discharges, hydraulic heads and temperature dynamics through space and time, within each of the hydrosystem compartments. The tool makes it possible to establish a fully consistent water and energy budget over a period of 17 years. It also simulates temperature evolution in each aquifer and evaluates that river thermal regulation mostly relies by order of importance on short wave radiations (109.3 W${\cdot }$m$^{-2}$), groundwater fluxes (48.1 W${\cdot }$m$^{-2}$) and surface runoff (22.7 W${\cdot }$m$^{-2}$).

As a component of the MAP project, the study of the flora in Northeast Asia (comprising Japan, South Korea, North Korea, Northeast China, and Mongolia) convincingly underscores the indispensability of precise and comprehensive diversity data for flora research. Due to variations in the description of flora across different countries in Northeast Asia, it is essential to update our understanding of the region's overall flora using the latest high-quality diversity data. This study employed the most recently published authoritative data from various countries to conduct a statistical analysis of 225 families, 1782 genera, and 10,514 native vascular species and infraspecific taxa in Northeast Asia. Furthermore, species distribution data were incorporated to delineate three gradients in the overall distribution pattern of plant diversity in Northeast Asia. Specifically, Japan (excluding Hokkaido) emerged as the most prolific hotspot for species, followed by the Korean Peninsula and the coastal areas of Northeast China as the second richest hotspots. Conversely, Hokkaido, inland Northeast China, and Mongolia constituted species barren spots. The formation of the diversity gradients is primarily attributed to the effects of latitude and continental gradients, with altitude and topographic factors within the gradients modulating the distribution of species. [ABSTRACT FROM AUTHOR]

Background: Domingo de Ramos, or Palm Sunday, is a traditional Christian religious event where devotees use ramos, which are bouquets currently elaborated from palm leaves and other natural elements. In various countries, it is assumed this use of biodiversity leads to the depletion of the species involved. However, other important aspects must be considered, including the role of the people who produce and sell these ramos, the associated symbolism that has been overlooked, as well as commercial aspects that have barely been documented. This ethnobotanical study evaluates the regional-scale cultural, biological and socioeconomic aspects associated with Domingo de Ramos in central Mexico from an emic perspective. Methods: Ethnographic and commercial information was obtained through interviews with ramos sellers in 28 municipalities in the state of Hidalgo, Mexico. We specifically sought sociodemographic data regarding the interviewees, as well as information pertaining to the ramos themselves and the palms. These aspects were explored with all of the sellers. The free list method was used to describe the uses and key elements associated with the ramos. Results: Although the ramos are used for religious purposes, they have eight different uses in the daily life of the sellers, the main one being "protection." They serve to protect families, crops and animals, as well as against several diseases. Likewise, they are considered valuable for diminishing strong storms. This belief in the protection conferred by the ramos preserves pre-Hispanic concepts and is combined with their use in blessing corresponding to Western beliefs. Ramos are made from 35 introduced and native plant species and comprise a base (made of palm, wheat or sotol), a "reliquia" (palm, rosemary, chamomile and laurel) and natural or artificial flowers. The ramos sellers are mostly adult women of indigenous origin and heads of family. Conclusions: This study of Domingo de Ramos, carried out at a regional scale, highlights a syncretism that is reflected in both the symbolic importance of ramos palm and in the species used, as well as socioeconomic aspects that had not previously been identified in the study area and reflect the occurrence of complex relationships in non-timber forest products that remain little addressed. [ABSTRACT FROM AUTHOR]

Regional scale modeling of coupled groundwater-surface water interaction in canal command areas is difficult due to high computational requirements and data insufficiency. Groundwater plays an essential role in the interaction process to fulfil the irrigation requirement in tail reaches of canal command areas. A comprehensive coupled model is required to simulate the canal command systems by incorporating the processes: (a) saturated groundwater flow, (b) unsaturated flow and (c) overland flow. In the present work, a fully-coupled model is developed that simulates saturated groundwater flow using Analytic Element Method (AEM), unsaturated flow using analytical solution and overland flow using Finite Volume Method (FVM) based Zero-inertia model. The Capability of the developed coupled model is demonstrated for Damodar Left Bank Main Canal (LBMC) under two canal regulation scenarios for "Boro Rice" cultivation season (Jan-Apr). Major canal water shortage is observed in LBMC during this season. It can be observed from the results that hydraulic heads in the upper reach are quite high whereas it is significantly lowering down as we move away from the main canal or in the lower reach where the groundwater is the main source of Boro rice irrigation. The considerable decline in hydraulic head values can be observed in LBMC which can be justified with a decrease in water supply and an increase in the area under Boro rice cultivation. [ABSTRACT FROM AUTHOR]

The aim of this study was to delimit potential rockfall propagation zones based on simulated 2 m resolution rockfall trajectories using Rockyfor3D for block volume scenarios ranging from 0.05–30 m3, with explicit inclusion of the barrier effect of standing trees, for an area of approx. 7200 km2 in Switzerland and Liechtenstein. For the determination of the start cells, as well as the slope surface characteristics, we used the terrain morphology derived from a 1 m resolution digital terrain model, as well as the topographic landscape model geodataset of swisstopo and information from geological maps. The forest structure was defined by individual trees with their coordinates, diameters, and tree type (coniferous or broadleaved). These were generated from detected individual trees combined with generated trees on the basis of statistical relationships between the detected trees, remote sensing-based forest structure type definitions, and stem numbers from field inventory data. From the simulated rockfall propagation zones we delimited rockfall hazard indication zones (HIZ), as called by the practitioners (because they serve as a basis for the Swiss hazard index map), on the basis of the simulated reach probability rasters. As validation, 1554 mapped past rockfall events were used. The results of the more than 89 billion simulated trajectories showed that 94% of the mapped silent witnesses could be reproduced by the simulations and at least 82% are included in the delimited HIZ. [ABSTRACT FROM AUTHOR]

The direct effects of relative humidity and soil on aboveground biomass (AGB) versus the indirect effects mediated by stand structural diversity remain unclear in forest ecosystems across large-scale elevation gradients. Forest inventory data containing 15,260 individual trees and 104 tree species from 200 forest plots were collected. The result shows that the relative humidity, elevation, and Coefficient of Variation of Diameter at breast height (CVD) significantly influence AGB in the Tropical Thorn Forest (TTF). Regarding elevation, CVD was positive and significant, and relative humidity and SR negatively impacted AGB in sub-tropical broad-leaved forests (STBLF). In moist temperate mixed forests (MTMF), soil phosphorus and CVD have a significant positive impact, while relative humidity, elevation, and SR negatively influence AGB. Elevation and CVD have positive, while SR and soil phosphorus have a negative and insignificant effect on AGB in Dry Temperate Conifer Forests (DTCF). Soil phosphorus and relative humidity positively affected AGB (β = 0.021), while elevation, CVD, and SR negatively affect AGB in dry temperate, pure pine forests (DTPPF). Relative humidity and soil phosphorus have a positive direct effect on AGB in multi-species forests. The current study suggests that AGB primarily depends on relative humidity, soil phosphorus, and elevation in different forest types. [ABSTRACT FROM AUTHOR]

Background and Aims The hart's tongue fern (HTF) complex is a monophyletic group composed of five geographically segregated members with divergent abundance patterns across its broad geographic range. We postulated hierarchical systems of environmental controls in which climatic and land-use change drive abundance patterns at the global scale, while various ecological conditions function as finer scale determinants that further increase geographic disparities at regional to local scales. Methods After quantifying the abundance patterns of the HTF complex, we estimated their correlations with global climate and land-use dynamics. Regional determinants were assessed using boosted regression tree models with 18 potential ecological variables. Moreover, we investigated long-term population trends in the USA to understand the interplay of climate change and anthropogenic activities on a temporal scale. Key Results Latitudinal climate shifts drove latitudinal abundance gradients, and regionally different levels of land-use change resulted in global geographic disparities in population abundance. At a regional scale, population isolation, which accounts for rescue effects, played an important role, particularly in Europe and East Asia where several hot spots occurred. Furthermore, the variables most strongly influencing abundance patterns greatly differed by region: precipitation seasonality in Europe; spatial heterogeneity of temperature and precipitation in East Asia; and magnitudes of past climate change, temperature seasonality and edaphic conditions in North America. In the USA, protected populations showed increasing trends compared with unprotected populations at the same latitude, highlighting the critical role of habitat protection in conservation measures. Conclusions Geographic disparities in the abundance patterns of the HTF complex were determined by hierarchical systems of environmental controls, wherein climatic and land-use dynamics act globally but are modulated by various regional and local determinants operating at increasingly finer scales. We highlighted that fern conservation must be tailored to particular geographic contexts and environmental conditions by incorporating a better understanding of the dynamics acting at different spatiotemporal scales. [ABSTRACT FROM AUTHOR]

Accurate and continuous crop phenology information at a regional scale is important for agronomic management and yield estimation. However, detecting continuous crop phenology remains challenging due to the low sensitivity of remote sensing signals to certain phenological stages and the limited of availability remote sensing images. Therefore, this study developed a layered strategy to detect continuous crop phenology. First, a novel Phenology Separability Index (PSI) is established to select features from the Gaussian probability density distribution. PSI quantifies the capability of optical vegetation indexes (VIs), Synthetic Aperture Radar (SAR) signals, and meteorological factors to distinguish between various phenological stages. Then, the multi-temporal sample is established to enhance training sample representation and quantity. Finally, a random forest model is trained using features extracted from multi-temporal samples to improve detection accuracy. This model effectively reduces phenological stage confusion due to redundant features and limited samples. In addition, this study validated its extensibility by mapping crop phenology in the cities of Acheng, Zhaozhou, Lishu, and Buxin and assessed its uncertainty using the Sobol approach. Results indicated that growing degree day has the highest separability among meteorological factors, surpassing both SAR singles and optical VIs. Moreover, the proposed layered strategy was robust, explaining 96% of spatial variation in crop phenology at the regional scale. The accuracy of the layered strategy method (total RMSE = 8.74 days) surpassed that of the multi-temporal sample method (total RMSE = 15.76 days) and the traditional method with a single-temporal sample (total RMSE = 17.21 days). In addition, this study indicated that optical VIs are prone to confuse with the early or late phenological stage of corn, whereas SAR singles are highly sensitive to jointing date.

Accurate, timely, and fine-resolution crop phenology is essential for determining the optimal timing of agronomic management practices supporting precision agriculture and food security. Synthetic Aperture Radar (SAR) methods, unaffected by cloud occlusion, have been widely applied in monitoring maize phenology. Nonetheless, their reliance on manual threshold settings, which depend on the user’s expertise, limits their applicability. Furthermore, the neglect of SAR’s potential for monitoring other phenological periods (e.g., seven-leaves date (V7), jointing date (JD), tassel date (TD), and milky date (MID)) hinders their robustness, particularly for regional-scale applications. To address these issues, this study used an adaptive dynamic threshold to evaluate the ability of the Sentinel-1 cross-polarization ratio (CR) in detecting the three-leaves date (V3), V7, JD, TD, MID, and maturity date (MD) of maize. We analyzed the effect of incidence angle, precipitation, and wind speed on Sentinel-1 features to identify the optimal feature for time series fitting. Then, we employed linear regression to determine the optimal threshold and developed an adaptive dynamic threshold for phenology detection. This approach effectively mitigated the speckle noise of Sentinel-1 and minimized artificial interference caused by customary conventional thresholds. Finally, we mapped phenology across 8.3 million ha in Heilongjiang Province. The results indicated that the approach has a higher ability to detect JD (RMSE = 11.10 d), MID (RMSE = 10.31 d), and MD (RMSE = 9.41 d) than that of V3 (RMSE = 32.07 d), V7 (RMSE = 56.37 d), and TD (RMSE = 43.33 d) in Sentinel-1. Compared with Sentinel-2, the average RMSE of JD, MID, and MD decreased by 4.14%, 35.28%, and 26.48%. Moreover, when compared to different thresholds, the adaptive dynamic threshold can quickly determine the optimal threshold for detecting each phenological stage. CR is least affected by incident angle, precipitation, and wind speed, effectively suppressing noise to reflect phenological development better. This approach supports the rapid and feasible mapping of maize phenology across broad spatial regions with a few samples.

In recent decades, the effect of human activities on freshwater cycle transgressed the catchment scale. In order to solve the global and regional water problems effectively, a new framework is needed to transform from the traditional hydrology which focuses on catchment processes to the global-scale hydrology which focuses on the earth system processes. Based on the recent progress of global hydrology, this paper summarizes the patterns of anthropogenic effect on global freshwater cycle, reviews the framework of Planetary Boundaries for Water (PBW) and the research progress, and analyzes the possible approaches of freshwater management from the catchment scale to the global scale. Directed by the Earth system science, PBW pushes forward water cycle research to the global scale from the local and catchment scale, and evaluates the safe operating space of global freshwater use, with the aim to maintain the functions of the Earth system. The framework provides an important merit to evaluate the global sustainability of water resources. Water management should not only balance off the relations of water resources, ecological environment and socio-economic development locally, but also the relations of water cycle, Earth system functions and global sustainability. PBW is an important supplement to the watershed or aquifer management, and puts forward a new framework for the global and regional water management. In order to meet the demand of water management under the new system of natural resources management in China, the study of PBW should focuses on the following aspects: to establish global hydrological models and simulation and prediction platform on the basis of better understanding of global water cycle; to advance the study of relations between PBW and other planetary boundaries such as land use, biodiversity, and atmospheric CO2; to improve the double evaluation approaches (resource and environment carrying capacity, territorial development suitability) for territorial spatial planning with the framework of PBW.

Slope has obvious scale-dependent characteristics and it changes with the change in DEM resolution, which brings uncertainty to the evaluation process of regional resource and environment. In this paper, one typical county in each of the six water erosion regions in China was selected as the sample area, respectively. Based on DEM data of ALOS DEM, ASTER GDEM and SRTM DEM with different spatial resolutions, slope characteristics, such as gradient, eigenvalue, frequency and cumulative frequency curves, were calculated by using the third-order inverse distance square weighted difference algorithm, to explore the ability of depicting terrain by these three DEM data. Based on the idea of geo-information map, the "surface-slope conversion atlas" under different resolutions was constructed to achieve the grading correction of slope extraction under low resolution. The results showed that: (1) with the resolution of DEM decreases, the slope information of each area tends to be more generalized and gradually concentrated. The slope frequency curve gradually changed from "tall and thin" to "short and fat", and the peak of the cumulative frequency curve moved to the low-slope area. Six sample areas showed different degrees of slope reduction. (2) In the process of slope grading correction, except for Maoxian, the proportion of low-resolution results converted to medium and low slope grades (0°–25°) is large. (3) The slope spectrum conversion method has a good correction effect on the errors generated by the slope extraction results of DEM90 and DEM30, and the correction rates reached 80% and 90%, respectively. A slope conversion atlas can effectively improve the expression ability of low-resolution DEM data on topography, which can provide a basis for regional resource and environment evaluation, and territorial space optimization. [ABSTRACT FROM AUTHOR]

While it is well accepted that climate change and growing water needs affect long-term sustainable water resourcesmanagement, performing accurate simulations of water cycle and energy balance dynamics at regional scale remains a challenging task. Traditional Soil-Vegetation-Atmosphere-Transfer (SVAT) models are used for numerical surface water and energy simulations. These models, by conception, do not account for the groundwater lower boundary that permits a full hydrosystem representation. Conversely, while addressing important features such as subsurface heterogeneity and river-aquifer exchanges, groundwater models often integrate overly simplified upper boundary conditions ignoring soil heating and the impacts of vegetation processes on radiation fluxes and root-zone uptakes. In this paper, one of the first attempts to jointly model water and energy fluxes with a special focus on both surface and groundwater at the regional scale is proposed on the Seine hydrosystem (78,650 km²), which overlays one of the main multi-aquifer systems of Europe. This study couples the SVAT model ORCHIDEE and the process-based hydrological-hydrogeological model CaWaQS, which describes water fluxes, via a one-way coupling approach from ORCHIDEE toward CaWaQS based on the blueprint published by de Marsily et al. [1978]. An original transport library based on the resolution of the diffusion/advection transport equation was developed in order to simulate heat transfer in both 1D-river networks and pseudo-3D aquifer systems. In addition, an analytical solution is used to simulate heat transport through aquitards and streambeds. Simulated ORCHIDEE surface water and energy fluxes feed fast surface runoff and slow recharge respectively and then is used as CaWaQS forcings to compute river discharges, hydraulic heads and temperature dynamics through space and time, within each of the hydrosystem compartments. The tool makes it possible to establish a fully consistent water and energy budget over a period of 17 years. It also simulates temperature evolution in each aquifer and evaluates that river thermal regulation mostly relies by order of importance on short wave radiations (109.3W·m-2), groundwater fluxes (48.1W·m-2) and surface runoff (22.7W·m-2). [ABSTRACT FROM AUTHOR]

Few commercial-scale carbon capture and storage (CCS) projects are currently operating in the world, with almost all in the USA and China. Despite a high number of CCS pilot-scale projects achieved in Europe, only two commercial-scale projects are operating today. The goal of this study is to present a case study in France to select a promising location to deploy a notable CCS pilot-scale project based on a multicriteria regional-scale approach. The methodology applied in this case study describes and assesses different aspects involved in CCS technology at the regional scale, and then an evaluation of economic key performance indicators (KPI) of CCS is carried out. The assessment at the regional scale gives an overview of where CCS could be applied, when CCS could be deployed and how to launch CCS considering the needs and concerns of stakeholders in the region. Technical aspects were mapped, such as the location of irreducible CO2 sources and long-lasting emissions and the location of storage resources and existing potential transport infrastructures. We identified the waste-to-energy and chemical sectors as the main CO2 sources in the region. An economic analysis of a hypothetical scenario of CCS deployment was elaborated considering three of the higher emitters in the region. A CCS scenario in the Paris Basin region with a deployment between 2027 and 2050 indicates a low CO2 cost per ton avoided between 43 EUR/t and 70 EUR/t for a cumulated total of 25 Mt and 16 Mt, respectively, of CO2 captured and stored for 26 years, including 7.7 Mt of CO2 from biomass (potential negative emissions). Storage maturity and availability of the resource are the most uncertain parameters of the scenario, although they are the key elements to push investment in capture facilities and transport. Geological storage pilot projects are mandatory to prove storage resource and should be located in strategic locations close to potential CO2 sources in case of confirmation of proven resources. Well-perceived pilot-scale projects are the first step to start engaging in deciding and investing in commercial-scale CCS projects.

Geochemical tracers have the potential to provide valuable insights for constructing conceptual models of groundwater flow, especially in complex geological contexts. Nevertheless, the reliability of tracer interpretation hinges on its integration into a robust geological framework. In our research, we concentrated on delineating the groundwater flow dynamics in the Innisfil Creek watershed, located in Ontario, Canada. We amalgamated extensive hydrogeological data derived from a comprehensive 3D geological model with the analysis of 61 groundwater samples, encompassing major ions, stable water isotopes, tritium, and radiocarbon. By seamlessly incorporating regional physiographic characteristics, flow pathways, and confinement attributes, we bolstered the efficiency of these tracers, resulting in several notable findings. Firstly, we identified prominent recharge and discharge zones within the watershed. Secondly, we observed the coexistence of relatively shallow and fast-flowing paths with deeper, slower-flowing channels, responsible for transporting groundwater from ancient glacial events. Thirdly, we determined that cation exchange stands as the predominant mechanism governing the geochemical evolution of contemporary water as it migrates toward confined aquifers situated at the base of the Quaternary sequence. Fourthly, we provided evidence of the mixing of modern, low-mineralized water originating from unconfined aquifer units with deep, highly mineralized water within soil–bedrock interface aquifers. These findings not only contribute significantly to the development a conceptual flow model for the sustainable management of groundwater in the Innisfil watershed, but also offer practical insights that hold relevance for analogous geological complexities encountered in other regions.

Grazing exclusion (GE) and rest grazing (RG) are important management systems for the restoration of degraded grassland ecosystems. In order to evaluate the effects and mechanisms of different grazing management systems on the scale dependency of species diversity, plant community indices and soil variables were determined in 32 plots in the Qilian Mountains in Gansu Province. The results show that diversity effects and their regulating mechanisms had space-scale dependence under different grazing management systems. The species richness and species diversity indices of RG grassland were significantly higher than those of GE at the regional scale. Species richness for RG and GE plots was 128 and 98, respectively, and the Shannon–Wiener and Simpson indices for RG and GE plots were 2.26 and 2.16, and 0.85 and 0.83, respectively. Additionally, three grazing management systems had a significant effect on species richness in mountain meadows, but different management systems had significantly different effects on species diversity indices in mountain meadows and temperate steppes. Meanwhile, soil variables only influenced species diversity at the regional scale. Most of the plant and soil variables at each scale had positive effects on species diversity. However, a negative correlation was seen between biodiversity and species coverage, mean plant height, soil porosity (SP) and bulk density (BD) under the two contrasting grazing management systems. In conclusion, choosing RG at the regional scale and selecting grazing management systems according to different grassland types at the local scale can help to restore degraded grassland vegetation.