Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac...Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies.展开更多
Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in ...Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in the middle reaches has degraded water quality.Rapid urbanization has further caused habitat fragmentation and biodiversity loss.Collectively,these challenges threaten human well-being and hinder sustainable development,making the construction and optimization of an ecological security pattern(ESP)urgently necessary.However,existing studies often fail to systematically integrate future landscape ecological risk(LER)assessment with ESP optimization.This study evaluated regional LER using the“ecological patches-ecological resistance surface(ERS)-ecological corridor”framework,combined with land-use predictions under three development scenarios,and optimized the ESP by adjusting the ERS and extracting ecological corridors.The results indicate that the LER in the WRB follows an“inverted N”distribution,with low-risk areas concentrated in forested mountain regions and high-risk areas mainly in cultivated land subject to intensive human activity.Across future scenarios,ESPs showed fewer ecological breakpoints and improved landscape connectivity than the 2020 baseline.Scenario-based differences emerged in the spatial configuration of ERS adjustments,with the ecological protection scenario yielding the lowest LER and most favorable ESP.This study demonstrates the deep integration of multi-scenario simulation with LER assessment,providing a new framework for ESP optimization.The findings have guiding significance for ecological protection and coordinated development in the WRB and offer a novel paradigm for sustainable development in ecologically fragile basins worldwide.展开更多
Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stag...Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stage,reflecting both external signs and internal features.TCM patterns are central to pattern differentiation,treatment,clinical practice,and theoretical development in TCM.However,scientific explanation of TCM patterns remains limited because of subjective diagnostic criteria,the absence of a standardized experimental medical system,and unclear biological mechanisms,which restrict the modernization and globalization of TCM.Addressing challenges such as strong subjectivity in diagnosis,lack of standardized experimental systems,and unclear biological mechanisms is necessary to clarify the scientific meaning of TCM patterns and to provide technical approaches for the modernization and globalization of TCM.A strategy focused on“pathogenic factors,genetic predisposition,and disease progression stages”was adopted.This approach included the following:(Ⅰ)constructing disease-pattern integrated biological models with animal models,organoids,and multi-organ chips;(Ⅱ)applying multi-omics technologies,such as spatial omics,single-cell omics,and dynamic metabolic flux omics;(Ⅲ)using artificial intelligence(AI)and big data for data integration and prediction of pattern evolution;and(Ⅳ)validating formula–pattern associations through the“pattern differentiation through formula efficacy”approach.These strategies directly address the main obstacles in TCM pattern research by providing objective,quantifiable,and reproducible methodologies.Constructing disease-pattern integrated models enabled cross-scale research platforms.Applying multi-omics technologies allowed analysis of complex biological bases.AI and big data approaches addressed challenges related to heterogeneous data.The“formula-based pattern differentiation”approach supported precise interventions and the development of new drugs.This interdisciplinary framework advances TCM pattern research by moving from empirical description to objective quantification.By integrating innovative approaches,the study establishes a foundation for systematic,evidence-based TCM diagnosis and treatment,supporting accuracy and promoting international recognition and modernization of TCM.The study shows that combining multi-omics technologies,AI-driven data analysis,and disease-pattern models enables objective quantification of TCM patterns and clarifies their biological mechanisms.展开更多
Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016...Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016;Sonne et al.,2025).Numerous studies have found that species richness of different taxa tends to decrease with increasing elevation and is modulated by latitudinal gradients(Peters et al.,2016;Dolson et al.,2024).This principle provides a crucial scientific basis for regional conservation planning.However,it still exhibits significant variations across different mountain ranges and taxa.展开更多
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s...Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests.展开更多
A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforat...A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design.展开更多
The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronou...The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronounced spatiotemporal heterogeneity and fragmented distribution patterns,rendering them highly sensitive to environmental change.This study integrated Sentinel-2 remote sensing imagery with the SedInConnect model to delineate wetland patch distributions and calculate the Index of Connectivity(IC)values across the basin.Based on IC values,we stratified field sampling sites into high-,moderate-,and lowconnectivity gradient groups to analyze the relationships among plant community characteristics,vegetation spatial patterns,and wetland connectivity in the Qaidam Basin.Partial Least Squares Path Modeling(PLSPM)was further employed to quantify the driving mechanisms underlying wetland vegetation characteristics.The results revealed that wetland connectivity across the basin was generally low,with IC values up to 1.32 and displaying a west-to-east decreasing gradient.The west and northwest were characterized by relatively continuous high-connectivity wetland networks,while fragmented and low-connectivity wetlands predominated in the east and southeast.Connectivity regulated wetland vegetation patterns primarily by affecting patch size,fragmentation,and internal adjacency.High-connectivity areas had higher class area(CA),largest patch index(LPI),and area-weighted mean patch size(AREA_AM)than low-connectivity areas.Connectivity had the strongest effect on vegetation coverage,which declined sharply from 87.577%in highconnectivity areas to 12.152%in low-connectivity areas.Meanwhile,species diversity showed a moderately negative response to connectivity changes,whereas species evenness remained relatively unaffected.PLS-PM explained 78.300%and 67.500%of the variance in vegetation community and vegetation pattern,respectively.Climate played a dominant role in shaping vegetation characteristics,with significant negative effects on both vegetation community and pattern.Topography influenced vegetation indirectly through climate,and connectivity was influenced by both drivers and exerted positive effects on vegetation community and pattern.This study reveals the multi-pathway driving mechanisms underlying vegetation pattern formation in alpine wetlands,providing a theoretical foundation and decision-support framework for the scientific conservation and adaptive management of wetlands in the Qaidam Basin.展开更多
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear...BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.展开更多
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She...Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers of α-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation in α-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems.展开更多
Objective:To elucidate the quantification and standardization of cold and hot patterns,the fundamental concepts in traditional Chinese medicine(TCM).Methods:This randomized cross-controlled trial recruited 30 healthy ...Objective:To elucidate the quantification and standardization of cold and hot patterns,the fundamental concepts in traditional Chinese medicine(TCM).Methods:This randomized cross-controlled trial recruited 30 healthy volunteers.Participants in Group 1 underwent 14 days of Coptis chinensis Franch.(C.chinensis,Huang Lian)treatment to shift their body toward the cold pattern,followed by 7 days of washout and 14 days of Cinnamomum cassia Presl(C.cassia,Rou Gui)treatment to shift their body toward the hot pattern.Participants in Group 2 underwent the opposite treatment.Blood and stool samples were collected for routine blood testing and full-length 16S rRNA metagenomic sequencing.Results:Red blood cells(RBC),hemoglobin(HGB),hematocrit(HCT),and blood platelet count(BPC)were increased by C.chinensis,whereas the mean corpuscular HGB concentration(MCHC)was increased by C.cassia.RBC,HGB,HCT,and BPC were positively associated with the cold pattern but negatively correlated with the hot pattern,whereas MCHC showed opposite relationships.C.chinensis-increased Blautia stercoris was positively correlated with RBC,HGB,and HCT under C.chinensis treatment,whereas C.cassia-enhanced Parabacteroides distasonis_A was positively associated with MCHC under C.cassia treatment.Interestingly,five indicators(RBC,HGB,HCT,Blautia stercoris,and Prevotella copri)had an area under the curve of 0.795 for predicting the cold pattern.Although three indicators(MCHC,Akkermansia sp004167605,and Parabacteroides distasonis_A)showed poor predictive ability for the hot pattern,when the individual’s gut microbiota experienced disturbance by cold Chinese materia medica stimulation,the predictive ability increased to 0.703.Conclusion:This study suggests that blood parameters and gut microbes may be potential indicators of hot and cold TCM patterns,which could benefit the objectivity and scientific rigor of TCM.展开更多
The rapid urbanization has significantly accelerated the expansion of cities and led to a notable increase in urban land surface temperature(LST).Currently,most studies mainly examine the effects of two-dimensional(2D...The rapid urbanization has significantly accelerated the expansion of cities and led to a notable increase in urban land surface temperature(LST).Currently,most studies mainly examine the effects of two-dimensional(2D)landscape patterns on LST variations,and research investigating the relationship between three-dimensional(3D)urban landscape patterns and LST remains relatively scarce.Therefore,this study utilizes partial correlation analysis and piecewise linear regression to systematically investigate the impacts of gray landscape indicators on LST variations under both 2D and 3D urban patterns,aiming to elucidate the complex relationship between 3D urban landscape patterns and LST dynamics.The results demonstrate that specific 3D building characteristics,particularly the area of low-rise buildings,building aggregation degree,shape complexity,and patch density of mid-rise buildings,serve as effective indicators of urban thermal environment risk.The analysis reveals that increased area-related indicators for low-rise buildings significantly exacerbate the LST rise,whereas modifications to the landscape shape of middle and high-rise buildings contribute to thermal mitigation.Additionally,when gray landscape aggregation exceeds 80%,the spatial concentration of mid-rise buildings exhibits a pronounced positive effect on moderating urban LST.These findings elucidate the mechanisms through which 3D landscape patterns influence urban thermal risks in Beijing,advancing the understanding of urban landscape-ecological processes interactions and providing crucial scientific support for landscape optimization and urban thermal environment risk mitigation strategies.展开更多
Global grassland degradation necessitates the identification of sustainable grazing management strategies.In semi-arid regions,grazing exclusion(GE),cold-season grazing(CG),and free grazing(FG)represent common practic...Global grassland degradation necessitates the identification of sustainable grazing management strategies.In semi-arid regions,grazing exclusion(GE),cold-season grazing(CG),and free grazing(FG)represent common practices in grassland ecosystems,yet the long-term ecological consequences of these patterns on plant community structure and soil aggregate stability remain inadequately elucidated.In this study,we evaluated the effects of GE,CG,and FG on soil organic carbon,soil water content,soil bulk density,soil aggregates,and vegetation indicators in Xilamuren steppe,a semi-arid grassland in northern China through field sampling and laboratory analyses in 2024.Our findings revealed that,compared to CG and FG,GE significantly enhanced aboveground and belowground biomass,species diversity,and soil physical-chemical properties in the 0–30 cm layer.The dominant plant species in GE and CG sites were Stipa krylovii,Leymus chinensis,and Agropyron cristatum,whereas Stipa krylovii,Artemisia frigida,and Leymus chinensis were predominant in FG site.Different grazing patterns led to distinct soil aggregate distributions,with>2.00 and<0.25 mm aggregates exhibiting the highest content in different soil layers depending on the grazing patterns.All grazing management strategies significantly improved soil aggregate stability,with the overall stability following the order:GE>CG>FG.Furthermore,random forest modeling identified plant species diversity,plant growth traits,and grazing patterns as the primary determinants of soil aggregate stability.Collectively,these results offer valuable insights into the sustainable management and ecological restoration of semi-arid grasslands under different grazing pressures.展开更多
The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoir...The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoirs,and its shale gas enrichment patterns are examined in this study using data from 1197 shale samples collected from 14 wells.Five basic and three key parameters,eight in all,are assessed for each sample.The five basic parameters include burial depth and the contents of four mineral types—quartz,clay,carbonate,and other minerals;the three key parameters,representing shale gas enrichment,are total organic carbon(TOC)content,porosity,and gas content.The SHapley Additive exPlanations(SHAP)analysis originated in game theory is used here in an interpretable machine learning framework,to address issues of heterogeneous data structure,noisy relationships,and multi-objective optimization.An evaluation of the ranking,contribution values,and conditions of changes for these parameters offers new quantitative insights into shale gas enrichment patterns.A quantitative analysis of the relationship between data-sets identifies the primary factors controlling TOC,porosity,and gas content of shale gas reservoirs.The results show that TOC and porosity jointly influence gas content;mineral content has a significant impact on both,TOC and porosity;and the burial depth governs porosity which,in turn,affects the conditions under which shale gas is preserved.Input parameter thresholds are also determined and provide a basis for the establishment of quantitative criteria to evaluate shale gas enrichment.The predictive accuracy of the model used in this study is significantly improved by the step-wise addition of two input parameters,namely TOC and porosity,separately and together.Thus,the game theory method in big data-driven analysis uses a combination of TOC and porosity to evaluate the gas content with encouraging results—suggesting that these are the key parameters that indicate source rock and reservoir properties.展开更多
Current image inpainting models are primarily designed to achieve a large receptive field(RF)using refinement networks to incorporate different scales.However,these models fail to adapt the use of different RFs to the...Current image inpainting models are primarily designed to achieve a large receptive field(RF)using refinement networks to incorporate different scales.However,these models fail to adapt the use of different RFs to the specific patterns of image damage,resulting in artifacts and semantic information confusion in repaired images.To address the problems of artifacts and semantic information confusion,inspired by different sensitivities of different RFs to inpainting the same image damaged patterns,this study proposes an image inpainting method based on multiple receptive fields(MRFs)and dynamic matching of damaged patterns.First,the parallel filter banks are used to extract the MRF feature groups.Second,the features are dynamically weighted and screened,guided by the mask image,to construct a relationship that adaptively matches the most relevant RF to each specific damaged pattern.A fast Fourier convolution based decoder is used to enhance the fusion of global contextual features during the reconstruction of high dimensional features into low dimensional images.Comparative experimental results show that the proposed method achieves better subjective and objective inpainting results on three public datasets:Paris StreetView,CelebA-HQ,and Places2.展开更多
A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependenci...A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China's ecological balance between supply and demand has become a global concern and is widely debated.In this study the'Ecological Footprint'method was used to analyze the supply-demand balance of China's ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index(ECCI)was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.展开更多
Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examine...Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.展开更多
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang...Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.展开更多
Open channel confluences,where two streams or rivers converge,play a crucial role in hydraulic engineering and river dynamics.These confluences are characterized by complex hydrodynamics influenced by the discharge ra...Open channel confluences,where two streams or rivers converge,play a crucial role in hydraulic engineering and river dynamics.These confluences are characterized by complex hydrodynamics influenced by the discharge ratios of merging water bodies.This study investigated the mixing structure at open channel confluences using three-dimensional numerical modeling.A comprehensive three-dimensional numerical model was developed and validated against a dataset obtained from controlled laboratory experiments.This dataset incorporated three-dimensional time-averaged velocity measurements.The skew-induced and stress-induced equation systems were adopted as the core governing equations,providing a framework for simulating various scenarios.A total of ten different cases were analyzed.The results highlighted the effect of discharge ratios on turbulence,lateral and vertical vorticities,and the distribution of mixing,which intensified with higher magnitudes of discharge ratios.The mixing structure,driven by velocity gradients and vorticity,revealed the significant role of lateral and vertical vorticities in determining hydrodynamic behaviors and mixing distributions at confluences.Specifically,the momentum ratio of incoming flows governed the spatial evolution of mixing processes.This study revealed that the distribution of mixing served as a key indicator for identifying the formation of mid-channel scours.High normalized velocities induced toward the left bank led to the superelevation of the water surface,enhancing the potential for bed material and the formation of significant scour holes beneath the elevated water surface.This novel approach provides a deeper understanding of the mixing patterns at confluences,particularly in scenarios with equilibrated discharge ratios but in different magnitudes.展开更多
This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gatheri...This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gathering and transmission trunk line project in the Weiyuan and Luzhou blocks.To gain deeper insights into dust migration patterns,numerical simulations were conducted.The study further analyzed dust migration behavior in small-section tunnels and large steep-sloped shafts,taking into account various factors such as ventilation distance,tunnel slope,and section size.The results indicate that optimal ventilation occurs at distances of 15 and 13 m.Additionally,dust concentration was notably lower when the tunnel slope was 0°,suggesting that a flat slope is more advantageous for construction projects where the outlet wind speed remains constant.Moreover,as the tunnel’s cross-sectional size increases,dust concentration decreases significantly,further underscoring the benefits of larger tunnel sections in mitigating dust accumulation.展开更多
基金supported by the Key Research and Development Plan Project of Heilongjiang Province (2022ZX02C13)。
文摘Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies.
基金supported by the National Natural Science Foundation of China[Grant No.42361040].
文摘Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in the middle reaches has degraded water quality.Rapid urbanization has further caused habitat fragmentation and biodiversity loss.Collectively,these challenges threaten human well-being and hinder sustainable development,making the construction and optimization of an ecological security pattern(ESP)urgently necessary.However,existing studies often fail to systematically integrate future landscape ecological risk(LER)assessment with ESP optimization.This study evaluated regional LER using the“ecological patches-ecological resistance surface(ERS)-ecological corridor”framework,combined with land-use predictions under three development scenarios,and optimized the ESP by adjusting the ERS and extracting ecological corridors.The results indicate that the LER in the WRB follows an“inverted N”distribution,with low-risk areas concentrated in forested mountain regions and high-risk areas mainly in cultivated land subject to intensive human activity.Across future scenarios,ESPs showed fewer ecological breakpoints and improved landscape connectivity than the 2020 baseline.Scenario-based differences emerged in the spatial configuration of ERS adjustments,with the ecological protection scenario yielding the lowest LER and most favorable ESP.This study demonstrates the deep integration of multi-scenario simulation with LER assessment,providing a new framework for ESP optimization.The findings have guiding significance for ecological protection and coordinated development in the WRB and offer a novel paradigm for sustainable development in ecologically fragile basins worldwide.
基金supported by the National Key Research and Development Program of China(2022YFC3500100)the National Natural Science Foundation of China(82230126 and U24A20800)+3 种基金Noncommunicable Chronic Diseases-National Science and Technology Major Project(2023ZD0502600 and 2023ZD0502601)National Science Fund for Excellent Young Scholars(82222075)the Incubation Program for the Science and Technology Development of Chinese Medicine Guangdong Laboratory(HQL2024PZ045 and HQCML-C-2024003)Guangdong Provincial Key Laboratory of Pattern and Formula(2022B1212010012).
文摘Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stage,reflecting both external signs and internal features.TCM patterns are central to pattern differentiation,treatment,clinical practice,and theoretical development in TCM.However,scientific explanation of TCM patterns remains limited because of subjective diagnostic criteria,the absence of a standardized experimental medical system,and unclear biological mechanisms,which restrict the modernization and globalization of TCM.Addressing challenges such as strong subjectivity in diagnosis,lack of standardized experimental systems,and unclear biological mechanisms is necessary to clarify the scientific meaning of TCM patterns and to provide technical approaches for the modernization and globalization of TCM.A strategy focused on“pathogenic factors,genetic predisposition,and disease progression stages”was adopted.This approach included the following:(Ⅰ)constructing disease-pattern integrated biological models with animal models,organoids,and multi-organ chips;(Ⅱ)applying multi-omics technologies,such as spatial omics,single-cell omics,and dynamic metabolic flux omics;(Ⅲ)using artificial intelligence(AI)and big data for data integration and prediction of pattern evolution;and(Ⅳ)validating formula–pattern associations through the“pattern differentiation through formula efficacy”approach.These strategies directly address the main obstacles in TCM pattern research by providing objective,quantifiable,and reproducible methodologies.Constructing disease-pattern integrated models enabled cross-scale research platforms.Applying multi-omics technologies allowed analysis of complex biological bases.AI and big data approaches addressed challenges related to heterogeneous data.The“formula-based pattern differentiation”approach supported precise interventions and the development of new drugs.This interdisciplinary framework advances TCM pattern research by moving from empirical description to objective quantification.By integrating innovative approaches,the study establishes a foundation for systematic,evidence-based TCM diagnosis and treatment,supporting accuracy and promoting international recognition and modernization of TCM.The study shows that combining multi-omics technologies,AI-driven data analysis,and disease-pattern models enables objective quantification of TCM patterns and clarifies their biological mechanisms.
基金supported by the Guizhou Provincial Science and Technology Projects(Grant Nos.ZK[2022]540 and[2023]099)the Survey of Amphibian and Reptile Resources in Leigongshan Nature Reserve and Literature Publishing Services(P5226002023000019).
文摘Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016;Sonne et al.,2025).Numerous studies have found that species richness of different taxa tends to decrease with increasing elevation and is modulated by latitudinal gradients(Peters et al.,2016;Dolson et al.,2024).This principle provides a crucial scientific basis for regional conservation planning.However,it still exhibits significant variations across different mountain ranges and taxa.
基金supported by the National Natural Science Foundation of China(32460380,42007042)State Key Laboratory of Subtropical Silviculture(SKLSSKF2023-06)+2 种基金Natural Science Foundation of Jiangxi Province(20242BAB25389)National Undergraduate Innovation and Entrepreneurship Training Program(202410410029X)Jiangxi Province Graduate Student Innovation Special Fund Project(YC2024-S330).
文摘Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests.
基金Project supported by the National Natural Science Foundation of China(Nos.12102321 and 52192633)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2025JCYBMS-050)。
文摘A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design.
基金funded by the National Natural Science Foundation of China(42230720)the 2023 Annual Qinghai Province"Kunlun Talents-High-end Innovation and Entrepreneurship Talent"Program Project.
文摘The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronounced spatiotemporal heterogeneity and fragmented distribution patterns,rendering them highly sensitive to environmental change.This study integrated Sentinel-2 remote sensing imagery with the SedInConnect model to delineate wetland patch distributions and calculate the Index of Connectivity(IC)values across the basin.Based on IC values,we stratified field sampling sites into high-,moderate-,and lowconnectivity gradient groups to analyze the relationships among plant community characteristics,vegetation spatial patterns,and wetland connectivity in the Qaidam Basin.Partial Least Squares Path Modeling(PLSPM)was further employed to quantify the driving mechanisms underlying wetland vegetation characteristics.The results revealed that wetland connectivity across the basin was generally low,with IC values up to 1.32 and displaying a west-to-east decreasing gradient.The west and northwest were characterized by relatively continuous high-connectivity wetland networks,while fragmented and low-connectivity wetlands predominated in the east and southeast.Connectivity regulated wetland vegetation patterns primarily by affecting patch size,fragmentation,and internal adjacency.High-connectivity areas had higher class area(CA),largest patch index(LPI),and area-weighted mean patch size(AREA_AM)than low-connectivity areas.Connectivity had the strongest effect on vegetation coverage,which declined sharply from 87.577%in highconnectivity areas to 12.152%in low-connectivity areas.Meanwhile,species diversity showed a moderately negative response to connectivity changes,whereas species evenness remained relatively unaffected.PLS-PM explained 78.300%and 67.500%of the variance in vegetation community and vegetation pattern,respectively.Climate played a dominant role in shaping vegetation characteristics,with significant negative effects on both vegetation community and pattern.Topography influenced vegetation indirectly through climate,and connectivity was influenced by both drivers and exerted positive effects on vegetation community and pattern.This study reveals the multi-pathway driving mechanisms underlying vegetation pattern formation in alpine wetlands,providing a theoretical foundation and decision-support framework for the scientific conservation and adaptive management of wetlands in the Qaidam Basin.
文摘BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.
基金supported by the Department of Biotechnology,Ministry of Science and Technology,Govt.India,under grant No.BT/Coord.Ⅱ/10/02/2016/22.03.2018the Indian Council of Social Science Research,New Delhi,India,for providing a short-term doctoral fellowship(RFD/Short-Term/2022-23/ENV/ST/66)。
文摘Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers of α-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation in α-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems.
基金supported by the National Natural Science Foundation of China(81973217).
文摘Objective:To elucidate the quantification and standardization of cold and hot patterns,the fundamental concepts in traditional Chinese medicine(TCM).Methods:This randomized cross-controlled trial recruited 30 healthy volunteers.Participants in Group 1 underwent 14 days of Coptis chinensis Franch.(C.chinensis,Huang Lian)treatment to shift their body toward the cold pattern,followed by 7 days of washout and 14 days of Cinnamomum cassia Presl(C.cassia,Rou Gui)treatment to shift their body toward the hot pattern.Participants in Group 2 underwent the opposite treatment.Blood and stool samples were collected for routine blood testing and full-length 16S rRNA metagenomic sequencing.Results:Red blood cells(RBC),hemoglobin(HGB),hematocrit(HCT),and blood platelet count(BPC)were increased by C.chinensis,whereas the mean corpuscular HGB concentration(MCHC)was increased by C.cassia.RBC,HGB,HCT,and BPC were positively associated with the cold pattern but negatively correlated with the hot pattern,whereas MCHC showed opposite relationships.C.chinensis-increased Blautia stercoris was positively correlated with RBC,HGB,and HCT under C.chinensis treatment,whereas C.cassia-enhanced Parabacteroides distasonis_A was positively associated with MCHC under C.cassia treatment.Interestingly,five indicators(RBC,HGB,HCT,Blautia stercoris,and Prevotella copri)had an area under the curve of 0.795 for predicting the cold pattern.Although three indicators(MCHC,Akkermansia sp004167605,and Parabacteroides distasonis_A)showed poor predictive ability for the hot pattern,when the individual’s gut microbiota experienced disturbance by cold Chinese materia medica stimulation,the predictive ability increased to 0.703.Conclusion:This study suggests that blood parameters and gut microbes may be potential indicators of hot and cold TCM patterns,which could benefit the objectivity and scientific rigor of TCM.
基金supported by the National Key Research and Development Program of China[grant number 2024YFF1306200]the National Natural Science Foundation of China[grant number 42171318].
文摘The rapid urbanization has significantly accelerated the expansion of cities and led to a notable increase in urban land surface temperature(LST).Currently,most studies mainly examine the effects of two-dimensional(2D)landscape patterns on LST variations,and research investigating the relationship between three-dimensional(3D)urban landscape patterns and LST remains relatively scarce.Therefore,this study utilizes partial correlation analysis and piecewise linear regression to systematically investigate the impacts of gray landscape indicators on LST variations under both 2D and 3D urban patterns,aiming to elucidate the complex relationship between 3D urban landscape patterns and LST dynamics.The results demonstrate that specific 3D building characteristics,particularly the area of low-rise buildings,building aggregation degree,shape complexity,and patch density of mid-rise buildings,serve as effective indicators of urban thermal environment risk.The analysis reveals that increased area-related indicators for low-rise buildings significantly exacerbate the LST rise,whereas modifications to the landscape shape of middle and high-rise buildings contribute to thermal mitigation.Additionally,when gray landscape aggregation exceeds 80%,the spatial concentration of mid-rise buildings exhibits a pronounced positive effect on moderating urban LST.These findings elucidate the mechanisms through which 3D landscape patterns influence urban thermal risks in Beijing,advancing the understanding of urban landscape-ecological processes interactions and providing crucial scientific support for landscape optimization and urban thermal environment risk mitigation strategies.
基金supported by the National Key Research and Development Program of China(2024YFF1306305)the Inner Mongolia Autonomous Region Natural Science Foundation Project(2025QN03106)+1 种基金the Research Start-up Project for the Introduction of High-level and Outstanding Doctoral Talent at Inner Mongolia Agricultural University(NDYB2024-42)the National Natural Science Foundation of China(42201012).
文摘Global grassland degradation necessitates the identification of sustainable grazing management strategies.In semi-arid regions,grazing exclusion(GE),cold-season grazing(CG),and free grazing(FG)represent common practices in grassland ecosystems,yet the long-term ecological consequences of these patterns on plant community structure and soil aggregate stability remain inadequately elucidated.In this study,we evaluated the effects of GE,CG,and FG on soil organic carbon,soil water content,soil bulk density,soil aggregates,and vegetation indicators in Xilamuren steppe,a semi-arid grassland in northern China through field sampling and laboratory analyses in 2024.Our findings revealed that,compared to CG and FG,GE significantly enhanced aboveground and belowground biomass,species diversity,and soil physical-chemical properties in the 0–30 cm layer.The dominant plant species in GE and CG sites were Stipa krylovii,Leymus chinensis,and Agropyron cristatum,whereas Stipa krylovii,Artemisia frigida,and Leymus chinensis were predominant in FG site.Different grazing patterns led to distinct soil aggregate distributions,with>2.00 and<0.25 mm aggregates exhibiting the highest content in different soil layers depending on the grazing patterns.All grazing management strategies significantly improved soil aggregate stability,with the overall stability following the order:GE>CG>FG.Furthermore,random forest modeling identified plant species diversity,plant growth traits,and grazing patterns as the primary determinants of soil aggregate stability.Collectively,these results offer valuable insights into the sustainable management and ecological restoration of semi-arid grasslands under different grazing pressures.
基金funded by the Technical Development(Entrusted)Project of Science and Department of SINOPEC(Grant No.P23240-4)the National Natural Science Foundation of China(Grant Nos.42172165,42272143 and 2025ZD1403901-05)。
文摘The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoirs,and its shale gas enrichment patterns are examined in this study using data from 1197 shale samples collected from 14 wells.Five basic and three key parameters,eight in all,are assessed for each sample.The five basic parameters include burial depth and the contents of four mineral types—quartz,clay,carbonate,and other minerals;the three key parameters,representing shale gas enrichment,are total organic carbon(TOC)content,porosity,and gas content.The SHapley Additive exPlanations(SHAP)analysis originated in game theory is used here in an interpretable machine learning framework,to address issues of heterogeneous data structure,noisy relationships,and multi-objective optimization.An evaluation of the ranking,contribution values,and conditions of changes for these parameters offers new quantitative insights into shale gas enrichment patterns.A quantitative analysis of the relationship between data-sets identifies the primary factors controlling TOC,porosity,and gas content of shale gas reservoirs.The results show that TOC and porosity jointly influence gas content;mineral content has a significant impact on both,TOC and porosity;and the burial depth governs porosity which,in turn,affects the conditions under which shale gas is preserved.Input parameter thresholds are also determined and provide a basis for the establishment of quantitative criteria to evaluate shale gas enrichment.The predictive accuracy of the model used in this study is significantly improved by the step-wise addition of two input parameters,namely TOC and porosity,separately and together.Thus,the game theory method in big data-driven analysis uses a combination of TOC and porosity to evaluate the gas content with encouraging results—suggesting that these are the key parameters that indicate source rock and reservoir properties.
基金The National Natural Science Foundation of China(No.62261032)the Central Government Guiding Funds for Local Scienceand Technology Development Program(No.25ZYJA026).
文摘Current image inpainting models are primarily designed to achieve a large receptive field(RF)using refinement networks to incorporate different scales.However,these models fail to adapt the use of different RFs to the specific patterns of image damage,resulting in artifacts and semantic information confusion in repaired images.To address the problems of artifacts and semantic information confusion,inspired by different sensitivities of different RFs to inpainting the same image damaged patterns,this study proposes an image inpainting method based on multiple receptive fields(MRFs)and dynamic matching of damaged patterns.First,the parallel filter banks are used to extract the MRF feature groups.Second,the features are dynamically weighted and screened,guided by the mask image,to construct a relationship that adaptively matches the most relevant RF to each specific damaged pattern.A fast Fourier convolution based decoder is used to enhance the fusion of global contextual features during the reconstruction of high dimensional features into low dimensional images.Comparative experimental results show that the proposed method achieves better subjective and objective inpainting results on three public datasets:Paris StreetView,CelebA-HQ,and Places2.
基金National Natural Science Foundation of China,No.40801223Research Project by Department ot Servlces and Management for Floating Population,Ministry of National Population and Family Planning Commission of P.R.China(2010-11)
文摘A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China's ecological balance between supply and demand has become a global concern and is widely debated.In this study the'Ecological Footprint'method was used to analyze the supply-demand balance of China's ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index(ECCI)was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.
基金supported by the Guangdong Basic and Applied Basic Research project (No.2020B0301030004)the Key-Area Research and Development Program of Guangdong Province (No.2020B1111360003)+1 种基金the National Natural Science Foundation of China (No.42105103)the Guangdong Basic and Applied Basic Research Foundation (No.2022A1515011554).
文摘Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.
基金National Social Science Foundation Program,No.22VRC163National Natural Science Foundation of China,No.42061043+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province,No.KYCX24_1008Innovation Project of Guangxi Graduate Education,No.YCSW2024473。
文摘Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.
文摘Open channel confluences,where two streams or rivers converge,play a crucial role in hydraulic engineering and river dynamics.These confluences are characterized by complex hydrodynamics influenced by the discharge ratios of merging water bodies.This study investigated the mixing structure at open channel confluences using three-dimensional numerical modeling.A comprehensive three-dimensional numerical model was developed and validated against a dataset obtained from controlled laboratory experiments.This dataset incorporated three-dimensional time-averaged velocity measurements.The skew-induced and stress-induced equation systems were adopted as the core governing equations,providing a framework for simulating various scenarios.A total of ten different cases were analyzed.The results highlighted the effect of discharge ratios on turbulence,lateral and vertical vorticities,and the distribution of mixing,which intensified with higher magnitudes of discharge ratios.The mixing structure,driven by velocity gradients and vorticity,revealed the significant role of lateral and vertical vorticities in determining hydrodynamic behaviors and mixing distributions at confluences.Specifically,the momentum ratio of incoming flows governed the spatial evolution of mixing processes.This study revealed that the distribution of mixing served as a key indicator for identifying the formation of mid-channel scours.High normalized velocities induced toward the left bank led to the superelevation of the water surface,enhancing the potential for bed material and the formation of significant scour holes beneath the elevated water surface.This novel approach provides a deeper understanding of the mixing patterns at confluences,particularly in scenarios with equilibrated discharge ratios but in different magnitudes.
基金supported by the National Natural Science Foundation of China under the Youth Project(Grant No.52204087)Additional support was provided by the Science and Technology Research Program of the Chongqing Municipal Education Commission(Grant No.KJQN202200746).
文摘This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gathering and transmission trunk line project in the Weiyuan and Luzhou blocks.To gain deeper insights into dust migration patterns,numerical simulations were conducted.The study further analyzed dust migration behavior in small-section tunnels and large steep-sloped shafts,taking into account various factors such as ventilation distance,tunnel slope,and section size.The results indicate that optimal ventilation occurs at distances of 15 and 13 m.Additionally,dust concentration was notably lower when the tunnel slope was 0°,suggesting that a flat slope is more advantageous for construction projects where the outlet wind speed remains constant.Moreover,as the tunnel’s cross-sectional size increases,dust concentration decreases significantly,further underscoring the benefits of larger tunnel sections in mitigating dust accumulation.
