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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
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
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Incorporating multiple scenarios and landscape ecological risk to optimize ecological security patterns: A Wei River Basin case study
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作者 Xueting Wu Jinghu Pan 《Chinese Journal of Population,Resources and Environment》 2026年第1期94-109,共16页
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
关键词 Ecological security pattern Multiple scenarios Landscape ecological risk Ecological security pattern optimization
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Thoughts on the scientific research of the connotation of traditional Chinese medicine patterns
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作者 Kang Xie Yulin Ouyang +1 位作者 Yong Wang Chun Li 《Journal of Traditional Chinese Medical Sciences》 2026年第1期3-11,共9页
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
关键词 Traditional Chinese medicine patterns Disease-pattern integrated model Multi-omics technology Artificial intelligence Pattern differentiation through formula efficacy
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Species Diversity and Elevational Patterns of Reptiles in the Leigongshan National Nature Reserve, Guizhou Province, China
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作者 Xue GOU Caichun PENG +7 位作者 Tuo SHEN Chaobo FENG Lang MU Jing LIU Haijun SU Xiujun TANG Shize LI Xingui LI 《Asian Herpetological Research》 2026年第1期31-33,共3页
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
关键词 patterns species diversity Leigongshan National Nature Reserve species richness Guizhou Province reptiles species diversity elevational patterns regional conservation plannin
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
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
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Thermal stability design for flexural wave bandgap of metamaterial plates with perforated and pre-curved patterns
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作者 Qian GENG Xing ZHOU +3 位作者 Mengyang WANG Xiongwei YANG Zhushan SHAO Yueming LI 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期443-472,I0001-I0004,共34页
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
关键词 metamaterial plate flexural vibration bandgap PERFORATION pre-curved pattern thermal stability
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Effects of wetland connectivity on plant communities and vegetation patterns in the Qaidam Basin
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作者 YUE Yifan MA Dengke +3 位作者 MA Yuanyuan KANG Wenrong ZHOU Guoying ZHAO Wenzhi 《Journal of Arid Land》 2026年第4期696-714,共19页
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
关键词 connectivity gradient wetland vegetation vegetation pattern community characteristics driving mechanisms
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
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
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Unravelling tree diversity patterns and responses to environmental gradients in a tropical forest landscape of the Western Ghats
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作者 Naveen Babu Kanda Ashaq Ahmad Dar +2 位作者 Kurian Ayushi Ayyappan Narayanan Narayanaswamy Parthasarathy 《Plant Diversity》 2026年第1期92-106,共15页
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
关键词 Alpha diversity Beta diversity Machine learning Structural equation modeling Vegetation patterns Western Ghats
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Typical blood parameters and gut microbiota alterations associated with the mutual conversion of cold and hot patterns induced by Chinese herbal medicines
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作者 Yanan Yang Yuxiao Li +2 位作者 Kebin Wang Shengxian Wu Chongming Wu 《Journal of Traditional Chinese Medical Sciences》 2026年第1期34-47,共14页
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
关键词 Traditional Chinese medicine Pattern differentiation Gut microbiota Coptis chinensis Franch Cinnamomum cassia Presl
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The influence of three-dimensional gray landscape patterns on urban surface temperature:A case study of Beijing,China
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作者 Linlin Zhao Kun Jia +5 位作者 Yanxu Liu Guofeng Tao Jie Li Bo Yuan Yuran Cui Shijiao Qiao 《Ecological Frontiers》 2026年第1期167-177,共11页
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
关键词 Land surface temperature 3D landscape patterns Thermal environment risk Landscape optimization
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Spatiotemporal patterns and driving forces of dust weather events in Central Asia from 2000 to 2020
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作者 LIU Yuhan ZHAO Yuanyuan +2 位作者 GAO Guanglei DING Guodong LI Ning 《Journal of Arid Land》 2026年第1期1-16,共16页
Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and dr... Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and driving forces of dust weather is highly important in this area.Based on the meteorological observations from 2000 to 2020,we examined the spatiotemporal characteristics of dust weather in the five Central Asian countries(Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan)via Theil-Sen trend analysis and Geodetector modeling method,quantitatively revealing the influence of environmental factors,such as temperature,precipitation,and vegetation,on the frequency of dust weather.The results showed that:(1)dust weather in Central Asia was mainly distributed in a large''dust belt''extending from west to east from northern part of the Caspian lowland desert,and concentrated in basins,plains,and other low-altitude areas.Strong dust weather mainly occurred in northern areas of the Aral Sea and southern edge of Central Asia,with a maximum annual frequency of 21.9%;(2)strong dust weather in Central Asia has fluctuated and slightly decreased since 2001.The highest frequency(1.1%)occurred in spring(from March to June);(3)from 2000 to 2020,changes such as spot shifting and shrinking occurred in the four main source areas(north of the Aral Sea,Kyzylkum Desert,Karakum Desert,and Garabogazköl Bay region),where sandstorms occurred in Central Asia,and northern Caspian lowland desert became the most important low-emission dust source in Central Asia;and(4)the combined effect of soil moisture and air temperature has the most significant influence on dust weather in Central Asia.This study provides a theoretical basis for sand prevention and sand control in Central Asia.In the future,Central Asia should focus on the rational utilization of land and water resources,and implement human interventions such as vegetation restoration and optimization of irrigation methods to curb further desertification in this area. 展开更多
关键词 Central Asia dust weather temporal and spatial distribution influencing factor Geodetector
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Influence of grazing patterns on the stability of soil aggregates in semi-arid grasslands
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作者 LI Haonian MENG Ruibing +2 位作者 MENG Zhongju GE Rile WU Xiaolong 《Journal of Arid Land》 2026年第2期322-338,共17页
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
关键词 soil aggregate stability grazing patterns grazing exclusion species diversity soil physical-chemical properties semi-arid grasslands
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Big data-driven analysis of shale gas enrichment patterns:A case study of the Wufeng–Longmaxi Formation in the Sichuan Basin and its periphery
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作者 Zongquan Hu Jin Meng +10 位作者 Wei Du Yitian Xiao Chuanxiang Sun Guanping Wang Baojian Shen Tianrui Ye Dongjun Feng Zengqin Liu Longfei Lu Ruyue Wang Qianru Wang 《Energy Geoscience》 2026年第1期166-178,共13页
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
关键词 Big data-driven analysis Primary controlling factor Shale gas enrichment pattern Wufeng–Longmaxi Formation Sichuan basin
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Biodiversity and biogeographic patterns of Nereididae(Annelida)across the Indo-Pacific Convergence Zone
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作者 Jieyang WENG Xuwen WU +2 位作者 Tiantian WANG Chenrui LI Linlin ZHANG 《Journal of Oceanology and Limnology》 2026年第1期322-339,共18页
Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the un... Nereididae is a prolific annelid family widely distributed in the world oceans,especially in the Indo-Pacific Convergence Zone(IPCZ).However,its biogeographic pattern remains unexplored in IPCZ.To contribute to the understanding of biodiversity and biogeography of Nereididae in the IPCZ,we integrated historical data of species distributions with those of model-predicted ones to determine the biogeographic patterns of nereid species,from which we projected to its future distribution patterns for 2090-2100 under different climate scenarios(SSP1-1.9 and SSP5-8.5).Functional diversity within IPCZ was assessed using functional richness,functional evenness,and functional disparity.Divergence times within Nereididae were estimated using three DNA marker genes(COI,16S,and 18S rRNA),and a time tree was constructed based on a strict molecular clock model.The IPCZ was established as a key Nereididae biodiversity hotspot through distribution modelling of 256 species(44 genera),and temperature emerging as the predominant climatic driver of species distribution patterns.The distribution of species and functional diversity is notable for its non-centralized pattern.We projected that by the end of the century,areas of medium-to-high species richness will expand significantly under the low-emission SSP1-1.9 climate scenario.However,under the high-emission SSP5-8.5 scenario,the suitability of these regions significantly declines,posing an increasingly severe threat to biodiversity.In addition,by molecular clock analysis,we revealed that the evolutionary divergence of extant nereidid species occurred mainly in the Cretaceous and Jurassic,suggesting that paleogeographical and environmental events,such as oceanic anoxic events,might have played a pivotal role in shaping the evolutionary trajectory and ecological adaptations of marine annelids.These findings highlight the importance of considering both current biodiversity patterns and historical contexts in conservation planning,and provided insights into the potential factors on the biogeographic distribution and evolutionary processes of Nereididae. 展开更多
关键词 NEREIDIDAE species distribution model(SDM) climate change BIODIVERSITY Indo-Pacific Convergence Zone(IPCZ)
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The Ecological Aesthetic Expression of Bamboo Grain Patterns and Their Application in Packaging Design
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作者 韩双品 刘涛 马淑 《鞋类工艺与设计》 2026年第6期195-197,共3页
竹材纹理作为自然界独特的视觉符号,承载着深厚的生态美学价值与文化内涵。竹材天然的纵向纹理呈现出简洁流畅的线性美感,体现了东方美学中的含蓄雅致,蕴含着生长、坚韧、虚心等丰富的文化象征意义。在生态美学理论框架下,竹材纹理的自... 竹材纹理作为自然界独特的视觉符号,承载着深厚的生态美学价值与文化内涵。竹材天然的纵向纹理呈现出简洁流畅的线性美感,体现了东方美学中的含蓄雅致,蕴含着生长、坚韧、虚心等丰富的文化象征意义。在生态美学理论框架下,竹材纹理的自然肌理特质同当代可持续发展理念高度契合,可以为包装设计提供全新的美学表达路径。 展开更多
关键词 竹材纹理 生态美学 包装设计 文化传承
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The Homogeneity of Distributional Patterns of the Global Terrestrial Animal,Plant and Microorganism under the Influence of Ecological Conditions 被引量:2
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作者 Shen Qi Lu Jiqi +2 位作者 You Zhixing Ren Yingdang Shen Xiaocheng 《Journal of Environmental Science and Engineering(A)》 2022年第4期121-137,共17页
The world animal geographical regionalization scheme and the plant geographical regionalization scheme have been formulated by zoologists and botanists respectively since the biogeography has been established.This res... The world animal geographical regionalization scheme and the plant geographical regionalization scheme have been formulated by zoologists and botanists respectively since the biogeography has been established.This research team initially confirmed the homogeneity of Chinese animal and plant geography.To explore the relationship between the distribution pattern of global animals,plants,and microorganisms,global 141,814 genera of terrestrial animals,17,526 genera of plants,21,321 genera of microorganisms,and their major taxa were analyzed using their proposed SGF(Similarity General Formula)and a new multivariate similarity clustering analysis method.Almost identical analytical results were obtained,meeting the requirements of statistics,geography,ecology and biology respectively.The expected consistency of their distribution pattern was achieved for the first time.We prove that the earth’s ecological conditions affect the homogeneity and accumulation of the distribution of animals,plants and microorganisms.Homogeneity determines the distribution pattern of global kinds of biological consistency,accumulation determines the impact of the evolutionary period on the breadth of distribution,microorganisms appear earliest,plants second,animals later,and their average distribution domain decreases in turn,reflecting these differences.Therefore,this study not only provides a theoretical basis and quantitative basis for the establishment of geographical regionalization scheme but also advances the development of biogeography to a new stage and raises the theory of biogeographic analysis to a new height. 展开更多
关键词 Distribution pattern clustering analysis terrestrial biology HOMOGENEITY geographical regionalization
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Identification and distribution patterns of the ultra-deep small-scale strike-slip faults based on convolutional neural network in Tarim Basin,NW China 被引量:1
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作者 Hao Li Jun Han +4 位作者 Cheng Huang Lian-Bo Zeng Bo Lin Ying-Tao Yao Yi-Chen Song 《Petroleum Science》 2025年第8期3152-3167,共16页
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco... The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents. 展开更多
关键词 Small-scale strike-slip faults Convolutional neural network Fault label Isolated fracture-vug system Distribution patterns
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Clustering Analysis of Distributional Patterns of Global Terrestrial Mammal 被引量:1
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作者 Shen Xiaocheng Lu Jiqi +3 位作者 Shen Qi Ren Yingdang Liu Xintao Zhang Shujie 《Journal of Environmental Science and Engineering(B)》 2022年第4期97-110,共14页
In this study,the world’s land(except Antarctica)is divided into 67 basic geographical units according to ecological types.Using our newly proposed MSCA(Multivariate Similarity Clustering Analysis)method,7,591 specie... In this study,the world’s land(except Antarctica)is divided into 67 basic geographical units according to ecological types.Using our newly proposed MSCA(Multivariate Similarity Clustering Analysis)method,7,591 species of modern terrestrial mammals belonging to 1,374 genera in 162 families and 2,378 species of mammals in the Wallace era before 1876 are quantitatively analyzed,and almost the same clustering results are obtained,with clear levels and reasonable clustering,which conform to the principles of geography,statistics,ecology and biology.It not only affirms and supports the reasonable kernel of Wallace’s scheme,but also puts forward suggestions that should be revised and improved.The large or small differences between the clustering results and the mammalian geographical zoning schemes of contemporary scholars are caused by different analysis methods,and they are highly consistent with the analysis results of chordates,angiosperms and insects in the world analyzed by the same method.Once again,it confirms the homogeneity of the global biological distribution pattern of major groups,and the possibility of building a unified biogeographic zoning system in the world. 展开更多
关键词 Terrestrial mammals DISTRIBUTION cluster analysis geographical division
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Spatiotemporal distribution patterns and exploration implications of multi-type coal-measure gases in the Daniudi gas field,Ordos Basin,China
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作者 Zhenrui Bai Fengcun Xing Zengqin Liu 《Energy Geoscience》 2025年第3期133-142,共10页
Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure g... Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure gases are yet to be clarified,directly impeding the sweet spot evaluation and exploration deployment of coal-measure gas.This study discussed the characteristics and distribution patterns of coal-measure gases in the Daniudi gas field in northeastern Ordos Basin,China,with abundant drilling data.The results indicate that the coal seams variably thin upward and are mainly seen in the first and second members of the Taiyuan Formation(also referred to as the Tai 1 and Tai 2 members,respectively)and the first member of the Shanxi Formation(Shan 1 Member).Nos.8,5 and 3 coal seams are laterally continuous,and significantly thicker in its southern part compared to the northern part.Moreover,carbonaceous mudstones and shales are better developed in the southern part,where limestones are only observed in the Tai 1 Member.Based on the main lithological types,we identified three lithologic roofs of coal seams,that is,limestone,mudstone,and sandstone,which determine the spatiotemporal distribution of coal-measure gases.Besides bauxite gas in the Benxi Formation,the coal-measure gases include tight-sand gas,coalbed methane(CBM),coal-measure shale gas,and tight-limestone gas,with CBM typically associated with coal-measure shale gas.The combinations of different types of coal-measure gas vary across different layers and regions.Tight-sand gas is well-developed in areas where tight sandstones are in contact with coal-measures.From the Taiyuan to the Shanxi formations,CBM gradually transitions into a combination of CBM and coal-measure shale gas,and coal-measure shale gas.Nos.8 and 5 coal seams in low-lying areas exhibit favorable gas-bearing properties due to their large thickness and favorable roof lithologies,serving as prospective play fairways.Mudstone and limestone roofs are more conducive to achieving good gas-bearing properties.The direct contact between sandstones and coal seams tends to result in the formation of tight-sand gas and a reduced gas content of CBM.While focusing on single types of gas reservoirs such as CBM and tight-sand gas,it is essential to consider the concurrent exploration of various coal-measure gas combinations to discover more additional gas resources and guide exploration deployment. 展开更多
关键词 Coal-measure gas Coal-measure shale gas Coalbed methane(CBM) Tight-sand gas Lithologic assemblage Distribution pattern of gas reservoirs
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