Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and...Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and source contributions to historical EOPEs is still lacking.In this paper,the K-means clustering method is applied to identify six dominant SWPs during the warm season in the Yangtze River Delta(YRD)region from 2016 to 2022.It provides an integrated analysis of the meteorological factors affecting ozone pollution in Hefei under different SWPs.Using the WRF-FLEXPART model,the transport pathways(TPPs)and geographical sources of the near-surface air masses in Hefei during EOPEs are investigated.The results reveal that Hefei experienced the highest ozone concentration(134.77±42.82μg/m^(3)),exceedance frequency(46 days(23.23%)),and proportion of EOPEs(21 instances,47.7%)under the control of peripheral subsidence of typhoon(Type 5).Regional southeast winds correlated with the ozone pollution in Hefei.During EOPEs,a high boundary layer height,solar radiation,and temperature;lowhumidity and cloud cover;and pronounced subsidence airflow occurred over Hefei and the broader YRD region.The East-South(E_S)patterns exhibited the highest frequency(28 instances,65.11%).Regarding the TPPs and geographical sources of the near-surface air masses during historical EOPEs.The YRD was the main source for land-originating air masses under E_S patterns(50.28%),with Hefei,southern Anhui,southern Jiangsu,and northern Zhejiang being key contributors.These findings can help improve ozone pollution early warning and control mechanisms at urban and regional scales.展开更多
The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structur...The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas.展开更多
This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eg...This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids.展开更多
With the accelerating urbanization process,issues related to the urban ecological environment have become increasingly prominent.Among these,greenway optimization is regarded as one of the key approaches to improving ...With the accelerating urbanization process,issues related to the urban ecological environment have become increasingly prominent.Among these,greenway optimization is regarded as one of the key approaches to improving urban ecological quality.As the capital of Anhui Province,Hefei is striving to build a comprehensive greenway network in line with its“Park City”strategy.However,the current development of Hefei’s greenways faces challenges such as delayed planning,limited functions,inadequate facilities,and weak operation and maintenance management.In this study,comparative analysis and literature review were combined to comprehensively summarize the current characteristics of greenway development in Hefei,and improvement suggestions were proposed in areas such as ecological restoration,functional expansion,facility establishment,and long-term management.It is suggested that Hefei should enhance the systematic and synergistic nature of its greenway system,create a city green space network with regional characteristics,and optimize the city’s environmental carrying capacity,so as to meet the diverse needs of the public and thereby provide theoretical support and practical guidance for the sustainable development of Hefei’s greenway system.展开更多
Hefei,capital of east China’s Anhui Province and once an inconspicuous inland city,is being transformed into a“city of the future.”FROM 2021 to 2025,the 14th Five-Year Plan period,Anhui Province has made notable pr...Hefei,capital of east China’s Anhui Province and once an inconspicuous inland city,is being transformed into a“city of the future.”FROM 2021 to 2025,the 14th Five-Year Plan period,Anhui Province has made notable progress in both technological innovation and strategic emerging industries.A good number of universities,national laboratories,and innovative enterprises have entered partnership,and a string of major scientific achievements have come to fruition.展开更多
Taking Hefei City as the research site,preliminary investigations were conducted into its aromatic plant resources to fill the gap in systematic research and establish a localized database in this study.Based on the a...Taking Hefei City as the research site,preliminary investigations were conducted into its aromatic plant resources to fill the gap in systematic research and establish a localized database in this study.Based on the analysis and organization of data on Hefei’s aromatic plant resources,the Analytic Hierarchy Process(AHP)was employed to quantitatively evaluate their comprehensive value(ecology,landscape,economy,etc.),so as to construct a comprehensive evaluation model for these resources and screen high-value plant species.Finally,based on the above objective investigation and analysis,recommendations were proposed for the landscape application of aromatic plant resources in Hefei,aiming to build an integrated ecological-landscape-economic value system.展开更多
Based on the investigation of colored-leaf plant resources in Hefei City,analytic hierarchy process(AHP)was used to construct a comprehensive evaluation system for colored-leaf plants in Hefei City.This system is comp...Based on the investigation of colored-leaf plant resources in Hefei City,analytic hierarchy process(AHP)was used to construct a comprehensive evaluation system for colored-leaf plants in Hefei City.This system is composed of three layers:leaf ornamental value,ecological adaptability,and other ornamental values,including 12 evaluation indicators.The landscape value of the 20 selected species of colored-leaf trees were comprehensively evaluated.The evaluation results show that 9 kinds of colored-leaf trees such as Ginkgo biloba and Tiadica sebifera are excellent(grade I,comprehensive evaluation value>3.5);7 species of colored-leaf trees such as Sophora japonica and Albizia juibissin are good(grade I 2.5≤comprehensive evaluation value≤3.5);4 types of colored-leaf trees such as Celtis sinensis and Pistacia chinensis are general(grade,comprehensive evaluation value<2.5).These results can provide theoretical references for the application of colored-leaf trees in uban green spaces of Hefei City.展开更多
At 20:08,on September 18,2024,an M4.7 earthquake occurred along the Tanlu fault zone in the Feidong County of Hefei,Anhui Province.This earthquake is the largest event in the modern history of Hefei,which caused subst...At 20:08,on September 18,2024,an M4.7 earthquake occurred along the Tanlu fault zone in the Feidong County of Hefei,Anhui Province.This earthquake is the largest event in the modern history of Hefei,which caused substantial social impact.To reveal the seismogenic structure of the M4.7 Feidong earthquake sequence and assess seismic risks,we use data from both the permanent seismic network and a temporary dense nodal array deployed in the epicentral region prior to the mainshock for:(1)accurate location of the earthquake sequence and determination of the focal mechanisms;(2)obtaining the spatiotemporal distribution,b-value,and half-day occurrence frequency of the earthquake sequence.The Sentinel-1 satellite data are used to analyze the coseismic displacement.Additionally,velocity models from regional tomography and local high-resolution 2D active-and passive-source surveys across the Tanlu fault zone in the epicentral area are also used to reveal the detailed geometry of the seismogenic fault.The results indicate:(1)the M4.7 Feidong earthquake sequence is concentrated around 10.5 km in depth along a NW-dipping,subvertical fault which trends NE and is approximately 5 km in length;the focal mechanism solution also reveals that the fault hosting the mainshock is a subvertical strike-slip fault,driven by the regional compressional stress in ENE-WSW;the coseismic horizontal displacement on the surface caused by the M4.7 mainshock has a maximum value close to 1 mm;(2)the regional velocity model shows significant lateral variation in v_(S) in the source region,with the mainshock occurring in the area with higher velocity;high-resolution P-wave velocity structures obtained by full waveform inversion from active sources,and S-wave velocity structures from passive-source ambient noise tomography indicate that the mainshock occurred along the boundary between high-and low-velocity bodies,and the seismogenic fault dips NW;the deep seismic reflection profiling shows that the mainshock occurred within the Jurassic strata;(3)based on these results,we suggest the seismogenic fault for the M4.7 Feidong earthquake is either the Zhuding-Shimenshan fault,one of the major faults in the Tanlu fault zone,or a hidden fault to the east;the intersection of the NE-trending Tanlu fault zone and the WNW-trending Feizhong fault,along with significant velocity variations,likely create local stress concentrations which could have triggered the M4.7 Feidong earthquake sequence;(4)the strong aftershocks following the M4.7 Feidong mainshock did not further extend the fault rupture zone;the active period of the Zhuding-Shimenshan fault was the late Early Pleistocene to Middle Pleistocene,and the imaging results indicate that this fault does not cut through the shallow Feidong depression.In conjunction with the small coseismic rupture area,it is inferred that the probability of surface-rupturing earthquakes in the future is relatively low.展开更多
The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper propo...The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper proposes an elastic fitting method based on fifth-order polynomial fitting for the precise analysis of microangular vibrations on grating surfaces.Compared with the traditional rigid body method,this method fully considers the three major elastic characteristics exhibited by optical components during vibration:significant phase differences,nonuniform deformation gradients,and spatial distribution differences in angular deformation.The research results indicate that this method can accurately reflect the actual vibration state of the grating surface,not only enabling the quantitative prediction of local angular microvibration but also establishing a reliable theoretical analysis framework for the stability assessment of high-precision instruments.展开更多
Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being th...Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being the most prevalent.In this study,the Analytic Hierarchy Process(AHP)was employed to assess the comprehensive value of 22 species of street trees applied along the main urban roads in Hefei City.Fourteen evaluation criteria were selected from four categories:morphological indices,functional indices,resistance indices,and management indices,to develop a comprehensive evaluation model.Based on a composite score derived from 22 street trees,these trees were classified into three distinct grades.Grade I(L≥3.0)exhibited a high comprehensive application value in Hefei City and included 6 tree species,such asPlatanus.Grade II(2.5≤L<3.0)also demonstrated a high comprehensive application value,comprising 15 tree species,includingCatalpabungei.In contrast,grade III(L<2.5)indicated a general comprehensive application value,represented by a single species,Cedrusdeodara.The evaluation results can offer theoretical insights for the selection of urban street trees.展开更多
The study made a comprehensive survey and analysis on application status and disposition features of Magnoliaceae plants in gardens of Hefei City.The survey showed that there were 24 tree species of Magnoliaceae belon...The study made a comprehensive survey and analysis on application status and disposition features of Magnoliaceae plants in gardens of Hefei City.The survey showed that there were 24 tree species of Magnoliaceae belonging to 6 genera having been applied in gardens of Hefei City,among which Magnolia grandiflora was the most widely applied and next was Magnolia denudate.Finally,scientific analysis had been conducted on application prospect of Magnoliaceae plants in garden greening.展开更多
Lithic (or gravel) composition analyses of the Jurassic Sanjianpu Formation and Fenghuangtai Formation in the Hefei basin show that the sediment provenance consists mainly of four kinds of rock units: the basement met...Lithic (or gravel) composition analyses of the Jurassic Sanjianpu Formation and Fenghuangtai Formation in the Hefei basin show that the sediment provenance consists mainly of four kinds of rock units: the basement metamorphic complex, granitic rocks, medium- and low-grade metamorphic rocks, and sandy and muddy sedimentary rocks, which are distributed along the bounding thrust belt. The whole stratigraphic section can be divided into 2 lithic sequences and 7 subsequences. The regular distribution and changes of lithic fragments and gravels in lithic (or gravel) sequences reflect that the bounding thrust belt of basin has undergone 2 thrusting cycles and 7 thrusting events. Lithic (or gravel) composition analyses of the basin fully reveal that the northern Dabie basement metamorphic complex was exhumed on the earth's surface in the Middle and Late Jurassic, and extensive intermediate and acid intrusive rocks were developed in the southern North Huaiyang or northern Dabie Mountains during the basin's syndepositional stage.展开更多
Urban construction land suitability evaluation （UCLSE） is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban constr...Urban construction land suitability evaluation （UCLSE） is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS （MCE-GIS）, is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects： a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process （AHP） method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination （WLC） and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei.展开更多
Size-classified daily aerosol mass concentrations and concentrations of water-soluble inorganic ions were measured in Hefei,China,in four representative months between September 2012 and August 2013.An annual average ...Size-classified daily aerosol mass concentrations and concentrations of water-soluble inorganic ions were measured in Hefei,China,in four representative months between September 2012 and August 2013.An annual average mass concentration of 169.09μg/m^3 for total suspended particulate（TSP）was measured using an Andersen Mark-II cascade impactor.The seasonal average mass concentration was highest in winter（234.73μg/m^3）and lowest in summer（91.71μg/m^3）.Water-soluble ions accounted for 59.49%,32.90%,48.62%and 37.08%of the aerosol mass concentration in winter,spring,summer,and fall,respectively,which indicated that ionic species were the primary constituents of the atmospheric aerosols.The four most abundant ions were NO3^-,SO4^2-,Ca^2＋ and NH4^＋.With the exception of Ca^2＋,the mass concentrations of water-soluble ions were in an intermediate range compared with the levels for other Chinese cities.Sulfate,nitrate,and ammonium were the dominant fine-particle species,which were bimodally distributed in spring,summer and fall;however,the size distribution became unimodal in winter,with a peak at 1.1–2.1μm.The Ca^2＋ peak occurred at approximately 4.7–5.8μm in all seasons.The cation to anion ratio was close to 1.4,which suggested that the aerosol particles were alkalescent in Hefei.The average NO3^-/SO4^2-mass ratio was 1.10 in Hefei,which indicated that mobile source emissions were predominant.Significant positive correlation coefficients between the concentrations of NH4^＋ and SO4^2-,NH4^＋ and NO3^-,SO4^2-and NO3^-,and Mg^2＋ and Ca^2＋ were also indicated,suggesting that aerosol particles may be present as（NH4）2SO4,NH4HSO4,and NH4NO3.展开更多
We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di...We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di- rection analysis and landscape pattern analysis, were employed. The results show that: 1) the residential land grew very rapidly in Hefei from 1978 to 2004, and the increased land was distributed mainly in the central city zone surrounded by a moat; however, after 1994, it was distributed mainly outside the 1th Ring Road; 2) the expansion speeds were very different in different directions: there exists a fastest expansion of residential land in the directions of NE-NNE, SW and SSE, and a slowest one in the directions of E and SEE; 3) the residential land growth went through four stages: slow circular expansion in 1978-1991, 'axes + fan wings' expansion in 1991-1994, more rapid circular expansion in 1994-2000 and 'fan-wings' expansion in 2000-2004; 4) the expansion intensity was also different in all directions in the period of 1978 to 1994, and the most was in SW and then NW; and 5) there were more and more residential land area, and the spatial agglomeration was improved increasingly.展开更多
In-depth research was conducted on the types,seasonal patterns,spatial levels,overwintering,summering,drought resistance,and disease and pest resistance of ornamental grasses in the road flower borders of Hefei,Anhui ...In-depth research was conducted on the types,seasonal patterns,spatial levels,overwintering,summering,drought resistance,and disease and pest resistance of ornamental grasses in the road flower borders of Hefei,Anhui Province.Through field investigations,a total of 36 ornamental grasses were identified,with Liliaceae having the most species and the Lamiaceae the least.The results show that there are more warm season ornamental grasses,of 23 species;Acorus gramineus and Melinis minutiflora have poor overwintering ability;Arrhenatherum elatius,Festuca glauca,and Stipa tenuissima have poor summer tolerance;most ornamental grasses have strong drought resistance and resistance to pests and diseases.The comprehensive investigation shows that ornamental grasses have good application prospects and adaptability in the road flower borders in Hefei city.展开更多
From the land use and ecological environment of Hefei Economic Circle,this paper established two sets of subsystem evaluation indicator system. It separately determined the weight coefficient of indicators in two indi...From the land use and ecological environment of Hefei Economic Circle,this paper established two sets of subsystem evaluation indicator system. It separately determined the weight coefficient of indicators in two indicator system. Using the coordination degree model,it made a scientific evaluation and analysis of coordinated development of land use and ecological environment in Hefei Economic Circle. Finally,on the basis of analysis results,it came up with pertinent recommendations for coordinated development of land use and ecological environment in Hefei Economic Circle.展开更多
The Hefei Basin is the largest basin in the North China landmass with complete and well-preserved Mesozoic and Cenozoic strata. In the basin there developed a suite of extremely thick ＂red beds＂ in the Mesozoic. Owi...The Hefei Basin is the largest basin in the North China landmass with complete and well-preserved Mesozoic and Cenozoic strata. In the basin there developed a suite of extremely thick ＂red beds＂ in the Mesozoic. Owing to complex evolution processes and a lack of paleontological traces, there have been controversies regarding the division and correlation of this suite of red beds. Based on results obtained in recent years in drilling, seismic and surface geological investigations and in consideration of relationships between seismic sequences and regional tectonic events, as well as evidence in paleontology, petrology and isotopic dating, this paper preliminarily puts forward the following ideas about the sequence stratigraphic framework of the continental ＂red beds＂ in the Hefei Basin. （1） The Zhougongshan Formation and the Yuantongshan Formation have similar lithologic, geophysical and paleontological characteristics, so we incorporate them into a single formation, called the Yuantongshan Formation, and the original Zhougongshan and Yuantongshan Formations are regarded as the upper and the lower parts of the newly defined Yuantongshan Formation. Its age is the Middle Jurassic; （2） the Zhuxiang Formation belongs to the Upper Jurassic Series and （3） the age of the Xiangdaopu Formation is the Lower Cretaceous. Furthermore, signatures of depositional evolution are analyzed in the paper based on features of seismic reflection, outcrops and drilling data. The Early and Middle Jurassic is characterized by a foreland basin, which is influenced mainly by uplift and longitudinal compression of the Dabieshan Mountains; the Lower Jurassic System has a relatively small depositional area; the Middle Jurassic strata are distributed extensively over the whole basin, marking the summit of basin development; a flexure basin is characteristic of the Late Jurassic, manifesting a joint effect of the Dabieshan and Zhangbaling Mountains with the former being more significant. In the Early Cretaceous, the Xiangdaopu Formation was distributed in the Daqiao depression, evidently affected by extension of the Tanlu fault; in the Late Cretaceous, the Hefei Basin was subjected to dismembering and the Zhangqiao Formation was distributed in the east-west direction along the downthrown side of the fault.展开更多
This paper carries out calculation and analysis of various kinds of ecological footprint and 104 yuan GDP in Hefei City during the period 2005-2010,and the results show that in recent years,the industrial economic dev...This paper carries out calculation and analysis of various kinds of ecological footprint and 104 yuan GDP in Hefei City during the period 2005-2010,and the results show that in recent years,the industrial economic development in Hefei City is accelerated,people's living standards are improved,and the momentum of urbanization is gathered.At the same time,as the resource utilization rate is increased year by year,the city's economic development has already begun to be resource-intensive.展开更多
This paper stated the background under which beautiful countryside construction was proposed;reviewed the new countryside construction profile of Hefei City before beautiful countryside construction was proposed;analy...This paper stated the background under which beautiful countryside construction was proposed;reviewed the new countryside construction profile of Hefei City before beautiful countryside construction was proposed;analyzed the practices of beautiful countryside construction of Hefei City from the perspective of the land consolidation when considering the development of new-type urbanization conjunctively;then,on the basis of the analysis,it proposed a consideration that the land consolidation and beautiful countryside construction practices of Hefei City should be used for reference,that is to say,the city should focus on beautiful countryside construction planning and comprehensively promote the land consolidation.And it also indicated that there were three kinds of relations needed to be treated well and"five combinations"needed to be done well in land consolidation.展开更多
基金supported by the National Natural Science Foundation of China(Nos.U19A2044,42105132,42030609,and 41975037)the National Key Research and Development Programof China(No.2022YFC3700303).
文摘Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and source contributions to historical EOPEs is still lacking.In this paper,the K-means clustering method is applied to identify six dominant SWPs during the warm season in the Yangtze River Delta(YRD)region from 2016 to 2022.It provides an integrated analysis of the meteorological factors affecting ozone pollution in Hefei under different SWPs.Using the WRF-FLEXPART model,the transport pathways(TPPs)and geographical sources of the near-surface air masses in Hefei during EOPEs are investigated.The results reveal that Hefei experienced the highest ozone concentration(134.77±42.82μg/m^(3)),exceedance frequency(46 days(23.23%)),and proportion of EOPEs(21 instances,47.7%)under the control of peripheral subsidence of typhoon(Type 5).Regional southeast winds correlated with the ozone pollution in Hefei.During EOPEs,a high boundary layer height,solar radiation,and temperature;lowhumidity and cloud cover;and pronounced subsidence airflow occurred over Hefei and the broader YRD region.The East-South(E_S)patterns exhibited the highest frequency(28 instances,65.11%).Regarding the TPPs and geographical sources of the near-surface air masses during historical EOPEs.The YRD was the main source for land-originating air masses under E_S patterns(50.28%),with Hefei,southern Anhui,southern Jiangsu,and northern Zhejiang being key contributors.These findings can help improve ozone pollution early warning and control mechanisms at urban and regional scales.
基金financially supported by the National Key Research and Development Program of China (2022YFC3005600)the Foundation of the Anhui Educational Commission (2023AH051198)+1 种基金the National Natural Science Foundation of China (42125401 and 42104063)the Joint Open Fund of Mengcheng National Geophysical Observatory (MENGO-202201)。
文摘The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas.
文摘This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids.
基金Sponsored by Research Team Project of Anhui Xinhua University(kytd202202)Anhui Provincial College Student Innovation Training Program Support Project(S202212216138,S202212216133,S202212216147)+1 种基金National College Student Innovation Training Program Support Project(AH202112216114)Key Project for Scientific Research in Anhui Higher Education Institutions(Natural Sciences Category)(2024AH050601).
文摘With the accelerating urbanization process,issues related to the urban ecological environment have become increasingly prominent.Among these,greenway optimization is regarded as one of the key approaches to improving urban ecological quality.As the capital of Anhui Province,Hefei is striving to build a comprehensive greenway network in line with its“Park City”strategy.However,the current development of Hefei’s greenways faces challenges such as delayed planning,limited functions,inadequate facilities,and weak operation and maintenance management.In this study,comparative analysis and literature review were combined to comprehensively summarize the current characteristics of greenway development in Hefei,and improvement suggestions were proposed in areas such as ecological restoration,functional expansion,facility establishment,and long-term management.It is suggested that Hefei should enhance the systematic and synergistic nature of its greenway system,create a city green space network with regional characteristics,and optimize the city’s environmental carrying capacity,so as to meet the diverse needs of the public and thereby provide theoretical support and practical guidance for the sustainable development of Hefei’s greenway system.
文摘Hefei,capital of east China’s Anhui Province and once an inconspicuous inland city,is being transformed into a“city of the future.”FROM 2021 to 2025,the 14th Five-Year Plan period,Anhui Province has made notable progress in both technological innovation and strategic emerging industries.A good number of universities,national laboratories,and innovative enterprises have entered partnership,and a string of major scientific achievements have come to fruition.
基金Sponsored by Provincial-level Undergraduate Innovation and Entrepreneurship Training Program of Anhui Xinhua University in 2023(S202312216045)Key Research Project of Natural Sciences in Colleges and Universities in Anhui Province(2023AH051816)General Teaching Research Project in Anhui Province(2022jyxm665).
文摘Taking Hefei City as the research site,preliminary investigations were conducted into its aromatic plant resources to fill the gap in systematic research and establish a localized database in this study.Based on the analysis and organization of data on Hefei’s aromatic plant resources,the Analytic Hierarchy Process(AHP)was employed to quantitatively evaluate their comprehensive value(ecology,landscape,economy,etc.),so as to construct a comprehensive evaluation model for these resources and screen high-value plant species.Finally,based on the above objective investigation and analysis,recommendations were proposed for the landscape application of aromatic plant resources in Hefei,aiming to build an integrated ecological-landscape-economic value system.
基金Sponsored by the Provincial Innovation Training Project for College Students of Anhui Xinhua University in 2023(S202312216044)Key Research Project of Natural Science in Universities of Anhui Province(2023AH051816)General Teaching Research Project of Anhui Province(2022jyxm665).
文摘Based on the investigation of colored-leaf plant resources in Hefei City,analytic hierarchy process(AHP)was used to construct a comprehensive evaluation system for colored-leaf plants in Hefei City.This system is composed of three layers:leaf ornamental value,ecological adaptability,and other ornamental values,including 12 evaluation indicators.The landscape value of the 20 selected species of colored-leaf trees were comprehensively evaluated.The evaluation results show that 9 kinds of colored-leaf trees such as Ginkgo biloba and Tiadica sebifera are excellent(grade I,comprehensive evaluation value>3.5);7 species of colored-leaf trees such as Sophora japonica and Albizia juibissin are good(grade I 2.5≤comprehensive evaluation value≤3.5);4 types of colored-leaf trees such as Celtis sinensis and Pistacia chinensis are general(grade,comprehensive evaluation value<2.5).These results can provide theoretical references for the application of colored-leaf trees in uban green spaces of Hefei City.
基金supported by the Anhui Province Science and Technology Breakthrough Plan Project(Key Project,No.202423l10050030)the National Natural Science Foundation of China(Fundamental Science Center Category B,No.4248830017)+4 种基金the Joint Funds of National Natural Science Foundation of China(No.U2139204)the National Natural Science Foundation of China Project(No.42104063)the Hefei Government Key Construction Project(No.2024BFFFD02048)the Earthquake Science and Technology Spark Program of the China Earthquake Administration(Nos.XH23020YA,XH24020B)the Anhui Mengcheng National Geophysical Observatory Joint Open Fund(No.MENGO-202307).
文摘At 20:08,on September 18,2024,an M4.7 earthquake occurred along the Tanlu fault zone in the Feidong County of Hefei,Anhui Province.This earthquake is the largest event in the modern history of Hefei,which caused substantial social impact.To reveal the seismogenic structure of the M4.7 Feidong earthquake sequence and assess seismic risks,we use data from both the permanent seismic network and a temporary dense nodal array deployed in the epicentral region prior to the mainshock for:(1)accurate location of the earthquake sequence and determination of the focal mechanisms;(2)obtaining the spatiotemporal distribution,b-value,and half-day occurrence frequency of the earthquake sequence.The Sentinel-1 satellite data are used to analyze the coseismic displacement.Additionally,velocity models from regional tomography and local high-resolution 2D active-and passive-source surveys across the Tanlu fault zone in the epicentral area are also used to reveal the detailed geometry of the seismogenic fault.The results indicate:(1)the M4.7 Feidong earthquake sequence is concentrated around 10.5 km in depth along a NW-dipping,subvertical fault which trends NE and is approximately 5 km in length;the focal mechanism solution also reveals that the fault hosting the mainshock is a subvertical strike-slip fault,driven by the regional compressional stress in ENE-WSW;the coseismic horizontal displacement on the surface caused by the M4.7 mainshock has a maximum value close to 1 mm;(2)the regional velocity model shows significant lateral variation in v_(S) in the source region,with the mainshock occurring in the area with higher velocity;high-resolution P-wave velocity structures obtained by full waveform inversion from active sources,and S-wave velocity structures from passive-source ambient noise tomography indicate that the mainshock occurred along the boundary between high-and low-velocity bodies,and the seismogenic fault dips NW;the deep seismic reflection profiling shows that the mainshock occurred within the Jurassic strata;(3)based on these results,we suggest the seismogenic fault for the M4.7 Feidong earthquake is either the Zhuding-Shimenshan fault,one of the major faults in the Tanlu fault zone,or a hidden fault to the east;the intersection of the NE-trending Tanlu fault zone and the WNW-trending Feizhong fault,along with significant velocity variations,likely create local stress concentrations which could have triggered the M4.7 Feidong earthquake sequence;(4)the strong aftershocks following the M4.7 Feidong mainshock did not further extend the fault rupture zone;the active period of the Zhuding-Shimenshan fault was the late Early Pleistocene to Middle Pleistocene,and the imaging results indicate that this fault does not cut through the shallow Feidong depression.In conjunction with the small coseismic rupture area,it is inferred that the probability of surface-rupturing earthquakes in the future is relatively low.
基金supported by the National Natural Science Foundation of China(Grant Nos.12372187 and 12402228)Fundamental Research Funds for the Central Universities(Grant No.WK2480000010)+3 种基金Fellowship of China Postdoctoral Science Foundation(Grant No.2024M753103)CAS Talent Introduction Program(Grant No.KJ2090007006)Anhui Provincial Natural Science Foundation(Grant No.2408085QA014)National Synchrotron Radiation Laboratory Joint Foundation(Grant Nos.KY2090000097 and KY2090000124).
文摘The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper proposes an elastic fitting method based on fifth-order polynomial fitting for the precise analysis of microangular vibrations on grating surfaces.Compared with the traditional rigid body method,this method fully considers the three major elastic characteristics exhibited by optical components during vibration:significant phase differences,nonuniform deformation gradients,and spatial distribution differences in angular deformation.The research results indicate that this method can accurately reflect the actual vibration state of the grating surface,not only enabling the quantitative prediction of local angular microvibration but also establishing a reliable theoretical analysis framework for the stability assessment of high-precision instruments.
基金Sponsored by Provincial-level Undergraduate Innovation Training Program of Anhui Xinhua University(S202312216043)Natural Science Key Research Program for Colleges and Universities in Anhui Province(2023AH051816)Anhui General Teaching Research Project(2022jyxm665).
文摘Through the investigation of the species of street trees located along the main urban roads in Hefei City,a total of 22 species were selected,belonging to 16 families and 22 genera,with the Sapindaceae family being the most prevalent.In this study,the Analytic Hierarchy Process(AHP)was employed to assess the comprehensive value of 22 species of street trees applied along the main urban roads in Hefei City.Fourteen evaluation criteria were selected from four categories:morphological indices,functional indices,resistance indices,and management indices,to develop a comprehensive evaluation model.Based on a composite score derived from 22 street trees,these trees were classified into three distinct grades.Grade I(L≥3.0)exhibited a high comprehensive application value in Hefei City and included 6 tree species,such asPlatanus.Grade II(2.5≤L<3.0)also demonstrated a high comprehensive application value,comprising 15 tree species,includingCatalpabungei.In contrast,grade III(L<2.5)indicated a general comprehensive application value,represented by a single species,Cedrusdeodara.The evaluation results can offer theoretical insights for the selection of urban street trees.
基金Supported by Forestry Science and Technology Supporting Project of "The Eleventh Five-year Planning" of China(2006BAD03A16)~~
文摘The study made a comprehensive survey and analysis on application status and disposition features of Magnoliaceae plants in gardens of Hefei City.The survey showed that there were 24 tree species of Magnoliaceae belonging to 6 genera having been applied in gardens of Hefei City,among which Magnolia grandiflora was the most widely applied and next was Magnolia denudate.Finally,scientific analysis had been conducted on application prospect of Magnoliaceae plants in garden greening.
基金This study was supported by the National Natural Science Foundation of China grants 49772119 and 49732080.
文摘Lithic (or gravel) composition analyses of the Jurassic Sanjianpu Formation and Fenghuangtai Formation in the Hefei basin show that the sediment provenance consists mainly of four kinds of rock units: the basement metamorphic complex, granitic rocks, medium- and low-grade metamorphic rocks, and sandy and muddy sedimentary rocks, which are distributed along the bounding thrust belt. The whole stratigraphic section can be divided into 2 lithic sequences and 7 subsequences. The regular distribution and changes of lithic fragments and gravels in lithic (or gravel) sequences reflect that the bounding thrust belt of basin has undergone 2 thrusting cycles and 7 thrusting events. Lithic (or gravel) composition analyses of the basin fully reveal that the northern Dabie basement metamorphic complex was exhumed on the earth's surface in the Middle and Late Jurassic, and extensive intermediate and acid intrusive rocks were developed in the southern North Huaiyang or northern Dabie Mountains during the basin's syndepositional stage.
基金Under the auspices of National Natural Science Foundation of China(No.41201168)Fundamental Research Funds for the Central Universities(No.2013HGXJ0207)
文摘Urban construction land suitability evaluation （UCLSE） is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS （MCE-GIS）, is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects： a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process （AHP） method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination （WLC） and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei.
基金supported by the Anhui Provincial Natural Science Foundation(No.1308085MD55)the China Special Fund for Meteorological Research in the Public Interest(NosGYHY201206011 and GYHY201406039)
文摘Size-classified daily aerosol mass concentrations and concentrations of water-soluble inorganic ions were measured in Hefei,China,in four representative months between September 2012 and August 2013.An annual average mass concentration of 169.09μg/m^3 for total suspended particulate（TSP）was measured using an Andersen Mark-II cascade impactor.The seasonal average mass concentration was highest in winter（234.73μg/m^3）and lowest in summer（91.71μg/m^3）.Water-soluble ions accounted for 59.49%,32.90%,48.62%and 37.08%of the aerosol mass concentration in winter,spring,summer,and fall,respectively,which indicated that ionic species were the primary constituents of the atmospheric aerosols.The four most abundant ions were NO3^-,SO4^2-,Ca^2＋ and NH4^＋.With the exception of Ca^2＋,the mass concentrations of water-soluble ions were in an intermediate range compared with the levels for other Chinese cities.Sulfate,nitrate,and ammonium were the dominant fine-particle species,which were bimodally distributed in spring,summer and fall;however,the size distribution became unimodal in winter,with a peak at 1.1–2.1μm.The Ca^2＋ peak occurred at approximately 4.7–5.8μm in all seasons.The cation to anion ratio was close to 1.4,which suggested that the aerosol particles were alkalescent in Hefei.The average NO3^-/SO4^2-mass ratio was 1.10 in Hefei,which indicated that mobile source emissions were predominant.Significant positive correlation coefficients between the concentrations of NH4^＋ and SO4^2-,NH4^＋ and NO3^-,SO4^2-and NO3^-,and Mg^2＋ and Ca^2＋ were also indicated,suggesting that aerosol particles may be present as（NH4）2SO4,NH4HSO4,and NH4NO3.
基金Under the auspices of the National Natural Science Foundation of China (No. 40371038)
文摘We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di- rection analysis and landscape pattern analysis, were employed. The results show that: 1) the residential land grew very rapidly in Hefei from 1978 to 2004, and the increased land was distributed mainly in the central city zone surrounded by a moat; however, after 1994, it was distributed mainly outside the 1th Ring Road; 2) the expansion speeds were very different in different directions: there exists a fastest expansion of residential land in the directions of NE-NNE, SW and SSE, and a slowest one in the directions of E and SEE; 3) the residential land growth went through four stages: slow circular expansion in 1978-1991, 'axes + fan wings' expansion in 1991-1994, more rapid circular expansion in 1994-2000 and 'fan-wings' expansion in 2000-2004; 4) the expansion intensity was also different in all directions in the period of 1978 to 1994, and the most was in SW and then NW; and 5) there were more and more residential land area, and the spatial agglomeration was improved increasingly.
基金National Training Programs of Innovation and Entrepreneurship for Undergraduates(202312216029)2022 Training Programs of Innovation and Entrepreneurship for Undergraduates of Anhui Province(S202212216122)+1 种基金Key Research Project of Natural Sciences in Universities of Anhui Province(2023AH051816)General Teaching Research Project of Anhui Province(2022jyxm665).
文摘In-depth research was conducted on the types,seasonal patterns,spatial levels,overwintering,summering,drought resistance,and disease and pest resistance of ornamental grasses in the road flower borders of Hefei,Anhui Province.Through field investigations,a total of 36 ornamental grasses were identified,with Liliaceae having the most species and the Lamiaceae the least.The results show that there are more warm season ornamental grasses,of 23 species;Acorus gramineus and Melinis minutiflora have poor overwintering ability;Arrhenatherum elatius,Festuca glauca,and Stipa tenuissima have poor summer tolerance;most ornamental grasses have strong drought resistance and resistance to pests and diseases.The comprehensive investigation shows that ornamental grasses have good application prospects and adaptability in the road flower borders in Hefei city.
文摘From the land use and ecological environment of Hefei Economic Circle,this paper established two sets of subsystem evaluation indicator system. It separately determined the weight coefficient of indicators in two indicator system. Using the coordination degree model,it made a scientific evaluation and analysis of coordinated development of land use and ecological environment in Hefei Economic Circle. Finally,on the basis of analysis results,it came up with pertinent recommendations for coordinated development of land use and ecological environment in Hefei Economic Circle.
基金supported by the National Natural Science Foundation of China (No. 41072080)China Post-doctor Science Foundation of China (No. 60878)National Project for Deep Exploration Technology and Experimentation (Sinoprobe-08)
文摘The Hefei Basin is the largest basin in the North China landmass with complete and well-preserved Mesozoic and Cenozoic strata. In the basin there developed a suite of extremely thick ＂red beds＂ in the Mesozoic. Owing to complex evolution processes and a lack of paleontological traces, there have been controversies regarding the division and correlation of this suite of red beds. Based on results obtained in recent years in drilling, seismic and surface geological investigations and in consideration of relationships between seismic sequences and regional tectonic events, as well as evidence in paleontology, petrology and isotopic dating, this paper preliminarily puts forward the following ideas about the sequence stratigraphic framework of the continental ＂red beds＂ in the Hefei Basin. （1） The Zhougongshan Formation and the Yuantongshan Formation have similar lithologic, geophysical and paleontological characteristics, so we incorporate them into a single formation, called the Yuantongshan Formation, and the original Zhougongshan and Yuantongshan Formations are regarded as the upper and the lower parts of the newly defined Yuantongshan Formation. Its age is the Middle Jurassic; （2） the Zhuxiang Formation belongs to the Upper Jurassic Series and （3） the age of the Xiangdaopu Formation is the Lower Cretaceous. Furthermore, signatures of depositional evolution are analyzed in the paper based on features of seismic reflection, outcrops and drilling data. The Early and Middle Jurassic is characterized by a foreland basin, which is influenced mainly by uplift and longitudinal compression of the Dabieshan Mountains; the Lower Jurassic System has a relatively small depositional area; the Middle Jurassic strata are distributed extensively over the whole basin, marking the summit of basin development; a flexure basin is characteristic of the Late Jurassic, manifesting a joint effect of the Dabieshan and Zhangbaling Mountains with the former being more significant. In the Early Cretaceous, the Xiangdaopu Formation was distributed in the Daqiao depression, evidently affected by extension of the Tanlu fault; in the Late Cretaceous, the Hefei Basin was subjected to dismembering and the Zhangqiao Formation was distributed in the east-west direction along the downthrown side of the fault.
基金Supported by Anhui Young Talents Fund(2011SQRW188)Anhui Provincial Natural Science Research Project(KJ2012B029)
文摘This paper carries out calculation and analysis of various kinds of ecological footprint and 104 yuan GDP in Hefei City during the period 2005-2010,and the results show that in recent years,the industrial economic development in Hefei City is accelerated,people's living standards are improved,and the momentum of urbanization is gathered.At the same time,as the resource utilization rate is increased year by year,the city's economic development has already begun to be resource-intensive.
基金Supported by Soft Science Research Project of Department of Land and Resources of Anhui Province(2012012)
文摘This paper stated the background under which beautiful countryside construction was proposed;reviewed the new countryside construction profile of Hefei City before beautiful countryside construction was proposed;analyzed the practices of beautiful countryside construction of Hefei City from the perspective of the land consolidation when considering the development of new-type urbanization conjunctively;then,on the basis of the analysis,it proposed a consideration that the land consolidation and beautiful countryside construction practices of Hefei City should be used for reference,that is to say,the city should focus on beautiful countryside construction planning and comprehensively promote the land consolidation.And it also indicated that there were three kinds of relations needed to be treated well and"five combinations"needed to be done well in land consolidation.
