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Sedimentary Structure Characteristics and Spatial Distribution Pattern of the Zhaoji Salt Mine Derived from Dense Array Ambient Noise Tomography
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作者 Hongwei Wang Xiaofeng Tian +5 位作者 Qiaoxia Liu Jia Cheng Ming Zhou Zhiping Xu Jiyan Lin Shuaipeng Zhu 《Journal of Earth Science》 2025年第5期2094-2108,共15页
Due to the lack of the three-dimensional structure of the Zhaoji Salt Basin,the salt mining enterprises have obvious clustering when choosing sites.Production capacity declines rapidly as mining deepens,and the enterp... Due to the lack of the three-dimensional structure of the Zhaoji Salt Basin,the salt mining enterprises have obvious clustering when choosing sites.Production capacity declines rapidly as mining deepens,and the enterprises are entering a stage of stagnation in production.In this study,a dense seismic array of 125 short-period stations was deployed around the core mining area and its vicinity of the salt mine industry,we used the ambient noise tomography(ANT)method to image the three-dimensional shear wave velocity structure at the depth shallower than 3 km.The results indicate:(1)The overall shear wave velocity in the study area is relatively lower,ranging from 0.8 to 1.8 km/s,which could be related to the loose and thick deposition of the Zhaoji sub-depression.(2)The three-dimensional shear wave velocity structure reveals that the sedimentary thickness of the Zhaoji sub-depression is deeper in the southeast and shallower in the northwest,with the sedimentary center located around Heping Town and Dahuangzhuang Town.(3)The Zhaoji salt mine is a low-velocity anomalous zone in the shear wave velocity structure with an inverse‘C'character spreading along Nanchenji Town and Zhaoji Town,with a depth ranging from approximately 1.2 to 2.8 km,it may be caused by the development of rock fissures due to water extraction and injection.The surrounding rock exhibits relatively high velocity,which reflects the morphological characteristics of the Zhaoji Salt Basin.The three-dimensional shear wave velocity model obtained in this study provides scientific guidance for the industrial exploitation of the Zhaoji salt mine and reference for salt exploration of the Hongze Salt Basin.It also provides an important basis for the seismic risk assessment of the salt basins.Simultaneously,it holds significant implications for exploring the application of ambient noise tomography method in spatial detection of salt mine belt. 展开更多
关键词 ambient noise tomography Zhaoji salt mine group velocity velocity structure sedimentary structure distribution pattern SEDIMENTOLOGY mineral deposits
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Impact of coking plant to heavy metal characteristics in groundwater of surrounding areas:Spatial distribution,source apportionment and risk assessments 被引量:1
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作者 Congqing Wang Wanjun Wang +5 位作者 ChaoWang Shixing Ren Yingjun Wu Meicheng Wen Guiying Li Taicheng An 《Journal of Environmental Sciences》 2025年第3期688-698,共11页
Coking industry is a potential source of heavy metals(HMs)pollution.However,its impacts to the groundwater of surrounding residential areas have not been well understood.This study investigated the pollution character... Coking industry is a potential source of heavy metals(HMs)pollution.However,its impacts to the groundwater of surrounding residential areas have not been well understood.This study investigated the pollution characteristics and health risks of HMs in groundwater nearby a typical coking plant.Nine HMs including Fe,Zn,Mo,As,Cu,Ni,Cr,Pb and Cd were analyzed.The average concentration of total HMswas higher in the nearby area(244.27μg/L)than that of remote area away the coking plant(89.15μg/L).The spatial distribution of pollution indices including heavy metal pollution index(HPI),Nemerow index(NI)and contamination degree(CD),all demonstrated higher values at the nearby residential areas,suggesting coking activity could significantly impact the HMs distribution characteristics.Four sources of HMs were identified by Positive Matrix Factorization(PMF)model,which indicated coal washing and coking emission were the dominant sources,accounted for 40.4%,and 31.0%,respectively.Oral ingestionwas found to be the dominant exposure pathway with higher exposure dose to children than adults.Hazard quotient(HQ)values were below 1.0,suggesting negligible non-carcinogenic health risks,while potential carcinogenic risks were from Pb and Ni with cancer risk(CR)values>10−6.Monte Carlo simulation matched well with the calculated results with HMs concentrations to be the most sensitive parameters.This study provides insights into understanding how the industrial coking activities can impact the HMs pollution characteristics in groundwater,thus facilitating the implement of HMs regulation in coking industries. 展开更多
关键词 Coking industry Heavy metal GROUNDWATER spatial distribution Source apportionment Monte Carlo simulation
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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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Territorial Ecological Restoration with a High-carbon Storage Focus in the Beibu Gulf Urban Agglomeration of China:Insights from Carbon Metabolism Spatial Security Patterns 被引量:1
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作者 QIN Menglin LIU Yuting +5 位作者 TAN Qianxi ZHU Ziming WU Xinyu JIANG Hongbo LI Hang SHI Qianqian 《Chinese Geographical Science》 2025年第1期73-91,共19页
This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking an... This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking and neutrality goals.This research ana-lyzes the spatial characteristics of carbon metabolism from 2000 to 2020 and uses models to identify stable carbon sink areas,positive carbon flow corridors,and carbon sequestration nodes.The goal is to construct a carbon metabolism spatial security pattern(CMSSP)and propose territorial ecological restoration strategies under different development demand scenarios.The results show the following:1)in 2020,the study area’s carbon sink decreased by 8.29×10^(4) t C/yr compared with that in 2010 and by 10.83×10^(4) t C/yr compared with that in 2000.High-carbon sinks were found mainly in mountainous areas,whereas low-carbon sinks are concentrated in urban con-struction land,rural residential areas,and land margins.2)From 2000 to 2020,the spatial security pattern of carbon metabolism tended to be‘high in the middle of the east and west and low in the gulf.’In 2000,2010,and 2020,16 stable carbon sinks were identified.The carbon energy flow density in Guangxi was greater than that in Guangdong and Hainan,with positive carbon flow corridors located primarily in Guangxi and Guangdong.The number of carbon sequestration nodes remained stable at approximately 15,mainly in Guangxi and Hainan.3)Scenario simulations revealed that under the Nature-based mild restoration scenario,the carbon sink rate will reach 611.85×10^(4) t C/yr by 2030 and increase to 612.45×10^(4) t C/yr by 2060,with stable carbon sinks increasing to 18.In the restora-tion scenario based on Anti-globalization,the carbon sink will decrease from 610.24×10^(4) t C/yr in 2030 to 605.19×10^(4) t C/yr in 2060,with the disappearance of some positive carbon flow corridors and stable carbon sinks.Under the Human-based sustainable restoration scenario,the carbon sink area will decrease from 607.00×10^(4) t C/yr in 2030 to 596.39×10^(4) t C/yr in 2060,with carbon sink areas frag-menting and positive carbon flow corridors becoming less dense.4)On the basis of the current and predicted CMSSPs,this study ex-plores spatial ecological restoration strategies for high-carbon storage areas in bay urban agglomerations at four levels:the land control region,urban agglomeration structure system,carbon sink structure and bay structure control region. 展开更多
关键词 carbon metabolism spatial security pattern(CMSSP) territorial ecological restoration carbon sink carbon storage capacity Beibu Gulf Urban Agglomeration China
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Latitudinal patterns of tree β-diversity and relevant ecological processes vary across spatial extents in forests of southeastern China
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作者 Maochou Liu Wenxiang Wu +5 位作者 Ke Wang Xinshuai Ren Xueqin Zhang Lei Wang Jing Geng Bo Yang 《Plant Diversity》 2025年第1期89-97,共9页
Latitudinal patterns of treeβ-diversity reveal important insights into the biogeographical processes that influence forest ecosystems.Although previous studies have extensively documentedβ-diversity within relativel... Latitudinal patterns of treeβ-diversity reveal important insights into the biogeographical processes that influence forest ecosystems.Although previous studies have extensively documentedβ-diversity within relatively small spatial extents,the potential drivers ofβ-diversity along latitudinal gradients are still not well understood at larger spatial extents.In this study,we determined whether treeβ-diversity is correlated with latitude in forests of southeastern China,and if so,what ecological processes contribute to these patterns of treeβ-diversity.We specifically aimed to disentangle the relative contributions from interspecific aggregation and environmental filtering across various spatial extents.We delineated regional communities comprising multiple nearby national forest inventory(NFI)plots around random focal plots.The number of NFI plots in a regional community served as a surrogate for spatial extent.We also used a null model to simulate randomly assembled communities and quantify the deviation(β-deviation)between observed and expectedβ-diversity.We found thatβ-diversity decreased along a latitudinal gradient and that this pattern was clearer at larger spatial extents.In addition,latitudinal patterns ofβ-deviation were explained by the degree of species spatial aggregation.We also identified environmental factors that driveβ-deviation in these forests,including precipitation,seasonality,and temperature variation.At larger spatial extents,these environmental variables explained up to 84%of theβ-deviation.Our results reinforce that ecological processes are scale-dependent and collectively contribute to theβ-gradient in subtropical forests.We recommend that conservation efforts maintain diverse forests and heterogeneous environments at multiple spatial extents to mitigate the adverse effects of climate change. 展开更多
关键词 Environmental filtering Latitudinal pattern Forest beta diversity spatial extent Species spatial aggregation Regional community
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Spatial distribution,influencing factors,and environmental risk assessments of mercury in surface soils over Xinjiang,northwestern China
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作者 Zhengzheng Yang Shiwei Sun +5 位作者 Xiwen Miao Shichang Kang Pengfei Chen Dipesh Rupakheti Zhaofu Hu Junming Guo 《Journal of Environmental Sciences》 2025年第12期555-568,共14页
Since scarce knowledge of soil mercury(Hg)concentrations and risks in the vulnerable Xinjiang,topsoils(0-15 cm)from its typical landscapes were extensively sampled.Topsoil total mercury(THg)concentrations varied broad... Since scarce knowledge of soil mercury(Hg)concentrations and risks in the vulnerable Xinjiang,topsoils(0-15 cm)from its typical landscapes were extensively sampled.Topsoil total mercury(THg)concentrations varied broadly between 0.9 and 35.3 ng/g,of which16.8%exceeded the background value of soil Hg for Xinjiang.Topsoil THg concentrations across various landscapes exhibited a declining order:farmland(11.7±6.0 ng/g)>grassland(10.5±8.5 ng/g)>woodland(10.2±8.2 ng/g)>desert(7.0±5.8 ng/g).The average topsoil THg concentration was higher in northwestern Xinjiang(11.3±7.2 ng/g)than that in southeastern Xinjiang(6.3±6.1 ng/g).Relatively high topsoil THg concentrations were observed near the cities with intensive human activities,followed by a gradual decline to the surroundings.The concentrations of topsoil THg were strongly correlated with the contents of total organic carbon(TOC),clay,silty,and sandy,and the distance from each sampling site to its nearest city,suggesting that the variation of topsoil Hg was significantly influenced by TOC content,soil granularity,and anthropogenic Hg emissions.Silty and TOC were the principal affecting factors,explaining 48.7%and 7.9%of the THg variation,respectively.The contamination and potential ecological risk evaluations revealed that topsoils in regions with dense populations were polluted with Hg and contained higher potential ecological risks.The health risk evaluations indicated that exposure risks of topsoil Hg were higher for children than those for adults.Fortunately,topsoil Hg posed acceptable risks to human health. 展开更多
关键词 MERCURY TOPSOIL LANDSCAPE spatial distribution Risk assessment XINJIANG
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Spatiotemporal patterns and spatial dislocation with economic level of China’s ecological resilience
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作者 Zedong Yang Hui Sun +1 位作者 Xuechao Xia Xuefeng Zhang 《Chinese Journal of Population,Resources and Environment》 2025年第1期40-48,共9页
Ensuring a harmonious coexistence between man and nature is crucial for China’s economic and social development.However,with increasing industrialization and urbanization,there is a growing mismatch between China’s ... Ensuring a harmonious coexistence between man and nature is crucial for China’s economic and social development.However,with increasing industrialization and urbanization,there is a growing mismatch between China’s ecological resilience(ER)and economic level(EL)of development,which poses a notable social threat.Currently,the link between ER and EL in China remains unclear,especially in terms of spatial dislocation(SD),referring to the disconnect between the locations where environmental impacts occur and those where economic benefits or activities are concentrated.Therefore,this paper aims to provide theoretical support and an empirical basis for policy-based solutions to address this gap.Based on the SD theory,this study systematically discusses the temporal changes,spatial patterns,and SD characteristics of China’s ER and EL using spatial auto-correlation and barycentric analysis to analyze data from 30 provinces covering the period 2011-2021.The key results are as follows.China’s ER shows a general trend of growth;however,its distribution is uneven.The spatial pattern generally decreases from the southeastern coastal provinces to the northwest.Moreover,a gradually increasing positive correlation is observed between the ER and EL,but this correlation varies by region,with some showing regional linkages and others developing independently.Finally,the dislocation index of ER and EL presents divergent results based on region-the eastern and central regions primarily show a high level of dislocation,whereas the western and northeastern regions show a low level of dislocation.The results provide a comprehensive overview of the spatiotemporal patterns in the association between ER and EL in China.The results emphasize that to balance sustainable regional development and ecological governance,a region-specific approach must be employed,prioritizing innovation-driven strategies for high ER in more developed regions and market-oriented strategies in less developed regions. 展开更多
关键词 Ecological resilience Economic level Spatiotemporal pattern spatial dislocation
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Spatiotemporal distribution patterns of macrobenthic communities and their relationship with environmental factors in the Shengsi Archipelago(Zhejiang,China)
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作者 Lingxiang Jin Yibo Liao +6 位作者 Peisong Yu Yanbin Tang Qinghe Liu Rongliang Zhang Lu Shou Jiangning Zeng Quanzhen Chen 《Acta Oceanologica Sinica》 2025年第1期113-126,I0001-I0011,共25页
Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced b... Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced by environmental factors of sediments and bottom water layer.We sampled a total of 12,11,10,and 11 stations in the Shengsi Archipelago during June 2010,August 2010,November 2020,and April 2021 respectively.A total of 124 species of macrobenthos were identified,with polychaetes being the dominant group.The abundance,biomass,and diversity indices exhibited no significant temporal differences.Similarly,biodiversity did not exhibit a clear spatial gradient,likely due to the small study area and the absence of significant differences in key factors such as depth.However,the stations with the lowest biodiversity values consistently appeared in the southwest region,possibly due to the impact of human activities.Significant differences in the macrobenthic community were observed between all months except between June and August,and mollusk Endopleura lubrica and polychaete Sigambra hanaokai were important contributors to these differences according to the results of the Similarity Percentages analysis.Suspended particulate matter(SPM)was identified as the primary driving factors of macrobenthic variability.In summary,the community structure underwent temporal changes influenced by complex current patterns,while biodiversity remained relatively stable.This study contributes to our understanding of the key environmental factors affecting macrobenthic communities and biodiversity.It also provides valuable data support for the long-term monitoring of macrobenthos and the environment in the Shengsi Archipelago. 展开更多
关键词 macrobenthic community Shengsi Archipelago distribution pattern BIODIVERSITY environmental factors
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Scyphozoa,Hydrozoa,and Ctenophora biodiversity and distribution patterns in the Xisha Islands revealed by environmental DNA metabarcoding
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作者 Tingting SUN Lijing YE +4 位作者 Lei WANG Saijun PENG Wenjing ZHANG Jianmin ZHAO Zhijun DONG 《Journal of Oceanology and Limnology》 2025年第5期1515-1527,共13页
Coral reefs support a wide range of organisms in the world,including jellyfish and their benthic relatives.However,quantifying the biodiversity of these organisms in reefs is a challenge because of their uneven distri... Coral reefs support a wide range of organisms in the world,including jellyfish and their benthic relatives.However,quantifying the biodiversity of these organisms in reefs is a challenge because of their uneven distribution and cryptic early life stages,requiring the validation of alternative techniques for biodiversity assessment.Here,the biodiversity and spatial distribution patterns of jellyfish and their benthic relatives,from the Scyphozoa,Hydrozoa,and Ctenophora taxa(hereafter referred to as SHC),were investigated in the coral reefs of Xisha,China,using environmental DNA(eDNA)metabarcoding technology by collecting shallow seawater,mesophotic seawater,and sediment samples.One-hundred and eighty-eight SHC species spanning two phyla(Cnidaria and Ctenophora),three classes,11 orders,65 families,and 104 genera were identified,among which hydrozoans were the most dominant taxa,accounting for 89.81% of all SHC species.SHC species showed low connectivity between shallow and mesophotic habitats,presenting a clear vertical distribution pattern in coral reefs.In the mesophotic coral ecosystems(MCEs),140 SHC species(84.34%)were detected,of which 39.76% were exclusive to MCEs,with Zanclea sp.1,Orthopyxis integra,and Fabienna sphaerica being the dominant species.Additionally,although SHC diversity in seawater was higher than that in the sediment samples,22 species were identified only in the sediment samples,indicating that sediment eDNA may represent a valuable supplementary tool for the investigation of SHC communities in hot spots.In addition to revealing the vast diversity of SHC species occupying coral reef ecosystems in the Xisha Islands,our findings confirm the potential of eDNA metabarcoding as an advanced tool for monitoring the biodiversity of cryptic species. 展开更多
关键词 eDNA metabarcoding mesophotic coral ecosystem BIODIVERSITY spatial distribution
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Revisiting each fracture size and spatial pattern:Inference from rock mass surface to interior
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作者 Yongqiang Liu Jianping Chen Jiewei Zhan 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1399-1417,共19页
Estimating fracture size is a fundamental aspect of rock engineering.However,determining the most probable diameter(MPD)from a fracture's surface trace remains challenging in the scientific community.The prevailin... Estimating fracture size is a fundamental aspect of rock engineering.However,determining the most probable diameter(MPD)from a fracture's surface trace remains challenging in the scientific community.The prevailing methodologies typically infer statistical distributions of fracture sizes rather than specific values.This research presents a novel approach to inferring the MPD and the true spatial distribution pattern of each fracture.The challenge lies in linking the inference process with the trace length of each fracture and the statistical characteristics of the entire outcrop.Additionally,it is necessary to address the non-unique inverse problem.The methodology comprises several key steps.Firstly,the issue of censoring bias is addressed by considering the lengths of the traces contained.Secondly,the orientation bias is corrected using the vector method,and the true mean trace length and standard deviation are estimated and derived.Thirdly,assuming a lognormal distribution for fracture sizes,the mean and standard deviation of diameters are derived through a high-order moment relationship between trace lengths and diameters,validated by Crofton's theorem.Finally,the MPDs of all trace samples are determined by relating MPDs to trace lengths and the standard deviation of diameters using stereology techniques.Furthermore,the true fracture spatial patterns are inverted based on spatial geometric relationships.The proposed methodology is validated through rigorous Monte Carlo simulation and applied in a practical engineering case study,demonstrating its potential for use in rock engineering applications. 展开更多
关键词 Trace length Fracture size Multi-scanline method STEREOLOGY spatial pattern Rectangular sampling window
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Stranding and sighting events reveal distribution patterns and potential threats to finless porpoises in the Qiantang River Estuary,China
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作者 Dongzi Pan Ying Li 《Acta Oceanologica Sinica》 2025年第5期56-67,共12页
Finless porpoises(FPs)serve as flagship species and key ecological indicators for assessing environmental quality.However,FPs are challenging to survey due to their elusive behavior and lack of distinctive features.St... Finless porpoises(FPs)serve as flagship species and key ecological indicators for assessing environmental quality.However,FPs are challenging to survey due to their elusive behavior and lack of distinctive features.Stranding and sighting events offer essential information on species diversity,distribution patterns,and potential threats.In this study,records from 1986 to 2023 were analyzed to assess the temporal and spatial distribution patterns of FP strandings and sightings in the Qiantang River Estuary,China.Results show an increase in the number of recorded events over time.Seasonal variations were evident,with a peak in strandings and sightings occurring in late winter.The frequency of records was higher during spring and moderate tides compared to neap tides,particularly in hydrologically normal years.Rapidly receding tides and sediment accumulation appear to restrict the activity space of FPs,thereby increasing the frequency of these events.Localized conditions associated with stranding and sighting events were classified into four categories:bifurcation zones,confluence zones,separation zones,and deep channels adjacent to concave banks.Deep channels,which are optimal for shipping,also elevate the risk of FP strandings.These findings offer valuable insights for the development and design of conservation strategies tailored to the needs of FPs in estuarine environments. 展开更多
关键词 finless porpoise distribution patterns STRANDINGS flagship species marine environment ecological indicator
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Spatial distribution of oxygen vacancy on ceria catalysts for chemoselective synthesis of lignin-derived cyclohexanol
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作者 Yuangao Wang Yu Luo +4 位作者 Chenwei Liu Feng Du Wenjuan Yan Xin Jin Chaohe Yang 《Journal of Energy Chemistry》 2025年第7期565-576,共12页
The synergy of metal/oxygen vacancy(O_(v))pairs is critical in catalyzing activation of C-H,C=C,and C-O bonds.However,gaining fundamental understanding on spatial distance of metallic and O_(v)sites on catalyst surfac... The synergy of metal/oxygen vacancy(O_(v))pairs is critical in catalyzing activation of C-H,C=C,and C-O bonds.However,gaining fundamental understanding on spatial distance of metallic and O_(v)sites on catalyst surface would lead to unexpected chemoselectivity toward important and challenging reactions.In this work,we have proposed and validated unique Ni-O-Ce-O_(v)enriched Ni/CeO_(2)catalysts prepared by a deposition-precipitation method,for the transfer hydrogenation of lignin-derived guaiacol toward cyclohexanol rather than benzene derivatives.The counter-intuitively designed high Ni loading Ni_(2)0/CeO_(2)catalyst(20 wt%Ni content)displays a distance of 0.5 nm for Ni/O_(v)pairs with a remarkable activity(TOF:166.5 h^(-1))and 90%+selectivity for C_(Ar)=C_(Ar)bond saturation,outperforming better metal-dispersed Ni_(5)/CeO_(2)catalyst with limited presence of Ni-O-Ce-O_(v)sites.The high hydrogenation activity against hydrogenolysis reactions on Ni_(2)0/CeO_(2)catalyst is attributed to tunable Ni/O_(v)distances,which constrain the cleavage of CAr-OH bond and deep deoxygenation.Such spatial distribution effect has also facilitated tandem dehydrogenation(O-H bond cleavage)and hydrogenation(C_(Ar)=C_(Ar)hydrogenation)reactions,leading to cyclohexanol as the target product in the absence of externally added H_(2).Insights into spatial distribution of O_(v)sites open an alternative perspective in designing efficient catalysts toward producing value-added cyclic oxygenates through upgrading of lignin compounds. 展开更多
关键词 Non-noble catalyst spatial distribution Oxygen vacancy Guaiacol transfer hydrogenation CYCLOHEXANOL
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Concentrations, spatial distribution, and human exposure of synthetic phenolic antioxidants in indoor dust from ten provinces in China
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作者 Xueyu Weng Wanyi Wang +2 位作者 Qingqing Zhu Chunyang Liao Guibin Jiang 《Journal of Environmental Sciences》 2025年第6期584-593,共10页
Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples w... Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples were collected from 10 provinces in China,and six SPAs(three parent SPAs and their three transformation products)were analyzed.The concentrations of6SPAs(the sum of six target compounds)ranged from 15.4 to 3210 ng/g(geometric mean(GM):169 ng/g).The highest concentration of6SPAswas found in Sichuan Province(GM:349 ng/g),which was approximately 4 times higher than that in Hubei Province(81.6 ng/g)(p<0.05).The concentrations of butylated hydroxytoluene(BHT),2,2'-methylene bis(4-methyl-6–tert-butylphenol)(AO2246),2,6-di–tert–butyl–1,4-benzoquinone(BHT-Q),2,6-di–tert–butyl–4-(hydroxymethyl)phenol(BHT-OH),and ∑_(p)-SPAs were substantially higher in dust from urban areas than rural areas(p<0.05).AO2246 concentration in dust from homes(GM:0.400 ng/g)was about 4 times higher than that in workplaces(0.116 ng/g)(p<0.01).Significantly higherp-SPAs concentrations were found in dust from homes(GM:17.5 ng/g)than workplaces(11.4 ng/g)(p<0.01).The estimated daily intakes(EDIs)of ∑_(6)SPAs exposed through dust ingestion were 0.582,0.342,0.197,0.076,and 0.080 ng/kg bw/day in different age groups,and exposed through dermal contact was 0.358,0.252,0.174,0.167,and 0.177 ng/kg bw/day.EDIs showed that the exposure risks of SPAs decreased with age.This is the first work to determine SPAs in dust from10 provinces in China and investigate the spatial distribution of SPAs in those regions. 展开更多
关键词 Indoor dust Synthetic phenolic antioxidants spatial distribution Composition profile Human exposure
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Spatial and Temporal Distribution Characteristics of PM 10 Concentration in Yantai City and Its Relationship with Meteorological Factors
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作者 Yumeng JIANG 《Meteorological and Environmental Research》 2025年第3期22-26,32,共6页
Based on the monitoring data of PM 10 concentration from six environmental monitoring stations and the ground meteorological observation data in Yantai City from 2019 to 2021,the spatial and temporal variation of PM 1... Based on the monitoring data of PM 10 concentration from six environmental monitoring stations and the ground meteorological observation data in Yantai City from 2019 to 2021,the spatial and temporal variation of PM 10 concentration and its relationship with meteorological factors were studied.The results show that from the perspective of temporal variation,the annual average of PM 10 concentration in Yantai City tended to decrease year by year.It was high in winter and spring and low in summer and autumn.In terms of monthly variation,the changing curve is U-shaped,and it was high in December and January but low in July and August.During a day,PM 10 concentration had two peaks.The first peak appeared approximately from 09:00 to 11:00,and the second peak can be found from 21:00 to 23:00.From the perspective of spatial distribution,PM 10 concentration was the highest in the development area and Fushan District.It was the highest in the west,followed by the east,while it was the lowest in the middle.The spatial difference rate was the highest in summer.Average temperature,relative humidity,wind speed and precipitation were the main meteorological factors influencing PM 10 concentration in Yantai area.PM 10 concentration was negatively correlated with average temperature and relative humidity,and the correlation was the most significant from June to October.It was negatively correlated with wind speed and precipitation,and the correlation was different in various months.The negative correlation was significant in summer and winter. 展开更多
关键词 Yantai City PM 10 spatial and temporal distribution Meteorological factors CORRELATION
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Impacts of prolonged dry season and artificial food supply on the wintering spatial distribution of Siberian Cranes:Implications for conservation
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作者 Deming Shen Fawen Qian +5 位作者 Shaoxia Xia Chaoyang Wang Xu Chu Zhenyu Wang Hongxing Jiang Yankuo Li 《Avian Research》 2025年第4期656-665,共10页
Poyang Lake,China's largest freshwater lake,is a critical wintering ground for most of the global Siberian Grane(Grus leucogeranus)population.However,increasingly prolonged dry seasons have degraded the natural we... Poyang Lake,China's largest freshwater lake,is a critical wintering ground for most of the global Siberian Grane(Grus leucogeranus)population.However,increasingly prolonged dry seasons have degraded the natural wetlands of Poyang Lake,forcing Siberian Cranes to shift to artificial habitats.From 2015 to 2023,field surveys revealed a substantial increase in the number of Siberian Cranes in artificial habitats,with peak counts reaching 3000individuals,accounting for up to 53%of the species'global population.Satellite telemetry of 13 individuals further confirmed the spatial use of these habitats,highlighting their consistent reliance on artificial sites over multiple years.Seven high-use hotspots were identified outside of Poyang Lake,including two artificial provisioning sites that supported dense foraging flocks for extended periods.Satellite telemetry confirmed this trend,with artificial habitats making up to 64.2%of the occurrence sites in some years.This reliance on artificial habitats was closely linked to the reduced tuber biomass in natural wetlands and low winter water levels in Poyang Lake,which collectively explained 83%of the variance in crane abundance in artificial habitats.Artificial habitat use peaked in December and January,indicating marked seasonal variation.Siberian Cranes also exhibited a pronounced circadian rhythm,foraging in artificial habitats during the day and returning to natural wetlands to roost at night.Despite the shift toward artificial habitats,natural wetlands remain critical for nighttime refuge.The continued dependence on artificial habitats raises concerns about disease transmission owing to dense congregations.Conservation strategies should prioritize both the careful management of artificial provisioning sites and the restoration of natural wetlands to improve food and habitat availability within natural ecosystems,ultimately enabling the return of Siberian Cranes to their traditional natural habitats. 展开更多
关键词 Artificial habitats Artificial provisioning Poyang lake Prolonged dry season Siberian crane spatial distribution
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Spatial distribution changes and habitat conservation of medicinal plant diversity in the Yinshan Mountains(China)under climate change
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作者 ZHAO Zeyuan BI Yaqiong +6 位作者 WEI Xinxin CHEN Yuan ZHANG Ru GUO Jingxia ZHANG Mingxu ZHANG Xiaobo LI Minhui 《Journal of Geographical Sciences》 2025年第7期1479-1496,共18页
Medicinal plant diversity(MPD)is an indispensable part of global plant diversity,serving as the foundation for human survival by offering remedies and preventive measures against diseases.However,factors such as overe... Medicinal plant diversity(MPD)is an indispensable part of global plant diversity,serving as the foundation for human survival by offering remedies and preventive measures against diseases.However,factors such as overexploitation,competition from invasive alien species,and climate change,threaten the habitats of medicinal plants,necessitating a comprehensive understanding of their spatial distribution and suitable habitats.We leveraged a decade of field survey data on medicinal plant distribution in the Yinshan Mountains,combined with spatial analysis,species distribution modeling,and the Carnegie Ames Stanford Approach(CASA)to explore the MPD spatial distribution and suitable habitats.Spatial analysis revealed that the central and eastern parts of Yinshan Mountains were the primary MPD hotspots,with no cold spots evident at various spatial scales.As the spatial scale decreased,previous non-significant regions transformed into hotspots,with instances where large-scale hotspots became insignificant.These findings offer valuable guidance for safeguarding and nurturing MPD across diverse spatial scales.In future climate change scenarios within the shared socioeconomic pathways(SSP),the habitat suitability for MPD in the Yinshan Mountains predominantly remains concentrated in the central and eastern regions.Notably,areas with high net primary productivity(NPP)values and abundant vegetation coverage align closely with MPD habitat suitability areas,potentially contributing to the region's rich MPD. 展开更多
关键词 medicinal plants diversity species distribution model climate change spatial analysis net primary productivity CASA model
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Spatial distribution and transport characteristics of river and sediment pollen in the middle and lower reaches of the Yellow River
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作者 LIU Dexin PAN Yanfang +3 位作者 HE Xueli WU Pengfei MA Jianhua GU Lei 《Journal of Geographical Sciences》 2025年第3期552-576,共25页
This paper selects sampling sections for the mainstream and tributaries of the middle and lower reaches of the Yellow River,collects river water and sediment samples during the flood season for pollen analysis,and use... This paper selects sampling sections for the mainstream and tributaries of the middle and lower reaches of the Yellow River,collects river water and sediment samples during the flood season for pollen analysis,and uses methods such as Geodetector to explore the distribution characteristics and influencing factors of pollen.The results show significant variations in vegetation composition across different watersheds,leading to notable differences in both the percentage and concentration of pollen types.Pollen concentration in river water is generally higher in the mainstream compared to tributaries,while sediment pollen percentage and concentration are typically lower in the mainstream than in tributaries.The concentration of suspended solids is the most significant factor affecting pollen concentration in the Yellow River,with this effect being particularly prominent outside the Shanxi-Shaanxi Gorge.Abundant coarse sand and rapid flow velocities are likely responsible for the high suspended solids concentration and lower pollen concentration observed in the mainstream of the Shanxi-Shaanxi Gorge.In sediments,clay content is the primary factor influencing pollen concentration,and its interaction with silt and flow velocity has a more prominent influence on pollen concentration.At the Yellow River section below the Shanxi-Shaanxi Gorge,sediment pollen and clay concentrations significantly increase.The changes in pollen concentration in the river water before and after the reservoir are consistent with the suspended solids concentration,while the changes in sediment pollen concentration are consistent with the clay content.Notably,pollen concentrations in sediments decrease more significantly after passing through a reservoir compared to changes observed in river water samples.Overall,there is a strong correlation between river pollen and topsoil pollen,which can provide a reliable reflection of the broader vegetation landscape of the watershed.The findings can provide support for paleoenvironmental reconstruction using pollen from alluvial sediments or lakes with river inflows. 展开更多
关键词 river pollen sediment pollen spatial distribution transmission mechanism middle and lower reaches of the Yellow River
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Salinity fronts shape spatial patterns in zooplankton distribution in Hangzhou Bay
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作者 Yepeng Xu Yiqi Wang +11 位作者 Lin Zhan Yijun Ou Kangning Jia Ming Mao Xuyu Zhu Zhibing Jiang Yuanli Zhu Wei Huang Ping Du Jiangning Zeng Lu Shou Feng Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期96-106,共11页
Ocean fronts play important roles in nutrient transport and in the shaping ecological patterns.Frontal zones in small bays are typically small in scale,have a complex structure,and they are spatially and temporally va... Ocean fronts play important roles in nutrient transport and in the shaping ecological patterns.Frontal zones in small bays are typically small in scale,have a complex structure,and they are spatially and temporally variable,but there are limited data on how biological communities respond to this variation.Hangzhou Bay,a mediumsized estuary in China,is an ideal place in which to study the response of plankton to small-scale ocean fronts,because three water masses(Qiantang River Diluted Water,Changjiang River Diluted Water,and the East China Sea current) converge here and form dynamic salinity fronts throughout the year.We investigate zooplankton communities,and temperature,salinity and chlorophyll a(Chl a) in Hangzhou Bay in June(wet perio d) and December(dry period) of 2022 and examine the dominant environmental factors that affect zooplankton community spatial variability.We then match the spatial distributions of zooplankton communities with those of salinity fronts.S alinity is the most important explanatory variable to affect zooplankton community spatial variability during both wet and dry periods,in that it contributes>60% of the variability in community structure.Furthermore,the spatial distributions of zooplankton match well with salinity fronts.During December,with weaker Qiantang River Diluted Water and a stronger secondary Changjiang River Plume,zooplankton communities occur in moderate salinity(MS,salinity range 15.6±2.2) and high salinity(HS,22.4±1.7) regions,and their ecological boundaries closely match the Qiantang River Diluted Water front.In June,different zooplankton communities occur in low salinity(LS,3.9±1.0),MS(11.7±3.6) and HS(21.3±1.9) regions.Although the LS region occurs abnormally in the central bay rather than its apex because of the anomalous influence of rising and falling tides during the sampling perio d,the ecological boundaries still match salinity interfaces.Low-salinity or brackish-water zooplankter taxa are relatively more abundant in LS or MS regions,and the biomass and abundance of zooplankton is higher in the MS region. 展开更多
关键词 ZOOPLANKTON spatial distribution salinity fronts Hangzhou Bay
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Study on Spatial Distribution Pattern of Thrip (Odentot hrips lati) on Alfalfa (Medicago sativa) 被引量:1
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作者 赵丽丽 王普昶 +1 位作者 刘玉良 陈彦希 《Agricultural Science & Technology》 CAS 2011年第7期990-993,共4页
[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots wit... [Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei's method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties. 展开更多
关键词 THRIPS Different degree distribution pattern ALFALFA
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Spatial Distribution Pattern and Application of Fourth-Generation Mature Larvae of Cotton Bollworm(Helicoverpa armigera Hübner) in Corn Field
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作者 李贺年 齐巧丽 +1 位作者 李德新 姚克荣 《Plant Diseases and Pests》 CAS 2011年第2期36-38,共3页
[ Objective] The paper was to study the spatial distribution pattern of fourth-generation mature larvae of cotton bellworm in corn field. [ Method] The plots with different occurrence densities of fourth-generation co... [ Objective] The paper was to study the spatial distribution pattern of fourth-generation mature larvae of cotton bellworm in corn field. [ Method] The plots with different occurrence densities of fourth-generation cotton bollworm were investigated from August to September in 2009. Six groups of sampling data were obtained, and seven indicators including aggregation index method, Iwao method and Taylor method, etc. were used to determine its spatial distribution pattern. [ Result ] Aggregation index test showed that in all plots, Moore I 〈 0, Lloyed m*/m 〈 1, Kuno Ca 〈 0, diffusion coefficient C 〈 1, diffusion index 16 〈 1, negative binomial distribution K 〈 0, indicating that mature larvae of cotton bollworm showed uniform distribution in summer corn. Iwae regression equation of fourth-genera- tion mature larvae of cotton boUworm in summer corn was m * = 0. 090 6 + 0. 766 9 m, r = 0. 986 3, indicating that the basic components of cotton bollworm distribu- ted was single individual, and mature larvae of cotton bollworm in summer corn showed uniform distribution. The optimal sampling number of fourth-generation ma- ture larvae of cotton bollworm in corn under different population densities could be calculated using formula N1 = ( 1. 090 6/m -0. 233 1 )/D2. [ Conclusion] The result provided basis for accurate evaluation of population quantities and variation law of cotton boUworm, as well as prediction and control of the pest. 展开更多
关键词 MAIZE Cotton bollworm spatial distribution pattern Sampling technique
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