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Journal of Geographical Sciences 2022年第4期32卷 605-616页

作者： CAO Liguo ZHOU Zhengchao WANG Ning XIAO Shun School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China

Due to the atmospheric nuclear weapon tests carried out,terrestrial environments have been extensively contaminated by global fallout of plutonium(Pu)worldwide.The^(239+240)Pu inventories in soil profiles from undisturbed and flat forest or grasslands(reference sites)mainly from Europe and Asia are considered as important background for evaluating soil erosion.Thus,we conducted a literature survey over an area extending from 2.6°W to 148.9°E and from 53.2°S to 76.6°N,with the purpose of analyzing the spatial distribution of^(239+240)Pu inventories and possible controlling factors.The aim of this work was to derive an empirical model of^(239+240)Pu inventory based on currently available^(239+240)Pu data,precipitation and latitude.The results show that,in general,the latitudinal distribution of^(239+240)Pu inventory was consistent with the UNSCEAR reports.However,the^(239+240)Pu inventories are higher than the UNSCEAR data,especially in the Northern Hemisphere.In addition,close relationships(at the 0.01 significance level)were identified between^(239+240)Pu inventories and annual precipitation and latitude.An empirical formula was therefore developed to estimate^(239+240)Pu inventories in soils based on latitude and precipitation data.However,future research may require more data of measured^(239+240)Pu inventories in soil profiles that can be used to compare,validate and improve upon the accuracy of the inferred empirical equation.

关键词： spatial distribution plutonium global fallout precipitation

spatial distribution of dissolved Pb,Hg,Cd,Cu and As in the Bohai Sea

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Journal of Environmental Sciences 2007年第9期19卷 1061-1066页

作者： WANG Chang-you WANG Xiu-lin College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China.

Characteristics of the spatial distribution of selected dissolved heavy metals were analyzed during large scale surveys from August t2 to 25, 2003 in the Bohai Sea. Dissolved Pb was the only element with average concentrations higher than the grade-one sea water quality standard of China. The spatial distribution of dissolved Pb in surface water was similar to those of Cd, Cu and As, where the isopleths generally indicated decreasing values from the bays to the central areas. Only for Hg did the high concentrations not only appear in Liaodong Bay, Bohai Bay and Laizhou Bay, but also in the Central Area, viz. not only in inshore but also in offshore areas. Vertical distributions of dissolved Pb, Cd, Cu and As were largely uniform, while that of dissolved Hg increased with depth. We infer that the input of pollutants from land was the main influencing factor for the detected distribution patterns of dissolved heavy metals, followed by the dynamics of sea water, release from bottom sediments and biochemical processes. Comparing with historical data, average concentrations of dissolved heavy metals appear to decline in recent years.

关键词： dissolved heavy metals spatial distribution pollution surveys Bohai Sea

spatial distribution of aerosol pollution based on MODIS data over Beijing,China

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Journal of Environmental Sciences 2007年第8期19卷 955-960页

作者： LI Ling-jun WANG Ying ZHANG Qiang YU Tong ZHAO Yue JIN Jun Beijing Municipal Environmental Monitoring Center Beijing 100044 China. Central University for Nationalities Beijing 100081 China Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

With the help of regression analysis, the relationships were detected between aerosol＇s contribution to apparent reflectance （ACR） derived from Moderate Resolution Imaging Spectroradiometer （MODIS） on board Terra and hourly PM10 mass concentration measured at 30 ground-based locations in Beijing for the August of 2003 and 2004. It was shown that there was a good correlation between the ACR and PM10 （linear correlation coefficient, R=0.56）. On the basis of this relationship, spatial distribution and possible sources of PM10 derived from MODIS were analyzed and two frequently heavily-polluted regions were found, namely downtown of the city and the district near Xishan Mountain. These two regions coincidently are also urban heat island centers. The foundings of this paper will be greatly useful for environmental monitoring and urban planning for Beijing, especially for the 2008 Olympic game to be held in Beijing.

关键词： MODIS PM10 spatial distribution

Quantifying spatial distribution of interrill and rill erosion in a loess at different slopes using structure from motion(SfM)photogrammetry

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International Soil and Water Conservation Research 2022年第3期10卷 393-406页

作者： Tao He Yang Yang Yangzi Shi Xiaozhen Liang Suhua Fu Gege Xie Baoyuan Liu Yingna Liu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China Beijing Key Laboratory of Environmental Remote Sensing and Digital Cities Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Chinese Academy of Sciences and Ministry of Water ResourcesYangling712100China

The spatial distribution of interrill and rill erosion is essential for unravelling soil erosion principles and the application of soil and water conservation practices.To quantify interrill and rill erosion and their spatial development,four 30-min rainfalls at 90 mm h^(-1)intensity were consecutively simulated on runoff plots packed with a loess at six slopes of 10°,15°,20°,25°,30°and 35°.The soil surface was measured using the structure from motion(SfM)photogrammetry upon each simulation run,and the runoff and sediment samples were collected and measured at every 10 min.Rills did not develop until the third simulation run.During the initial two runs,the lower third section was more severely eroded than the upper and middle thirds along the slope direction,yet the interrill erosion was statistically uniform from left to right.Rills tended to emerge by both sidewalls and in the lower portion in the third run.The corresponding rill erosion increased with slope from 10°to 20°and then decreased for the slopes steeper,which was consistent with the slope trend of the sediment yield directly measured.The rills expanded substantially primarily via head retreat and to a lesser extent via sideward erosion after receiving another 30-min rainfall.Rill erosion contributed 69.3%of the total erosion loss,and shifted the critical slope corresponding to the maximum loss from 20°to 25°.These findings demonstrate the significance of rill erosion not only in total soil loss but also in its relation to slope,as well as the effectiveness of SfM photogrammetry in quantifying interrill and rill erosion.

关键词： Interrill and rill erosion spatial distribution Structure from motion(SfM) photogrammetry Slope Rainfall simulation

spatial distribution of health risks for residents located close to solvent-consuming industrial VOC emission sources

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Journal of Environmental Sciences 2021年第9期33卷 38-48页

作者： Di Wang Xuan Li Xinmin Zhang Wenjuan Zhao Weiqi Zhang Shuaifeng Wu Xia Shao Lei Nie State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application Beijing Municipal Research Institute of Environment ProtectionBeijing 100037China China Institute of Water Resources and Hydropower Research Beijing 100038China

Emissions derived from the consumption of organic solvents have been proven to be the primary industrial source of volatile organic compounds(VOCs).In conjunction with epidemiologic studies, water-based paints(WBPs) and solvent-based paints(SBPs) were selected as representatives of newly developed solvents and traditional solvents, respectively,to simulate the effects of consuming solvents emitted during industrial production.And non-carcinogenic and carcinogenic risks to residents near emission sources were studied in detail.The results showed that the spatial distribution of health risks varied with meteorological conditions and type of emission source, and the prevailing wind direction strongly affected the distribution range and shape of the influenced area.The areas of influence maximized on heavy-polluting days for both WBP and SBP emission sources with the total span reaching 804 m and 16 km, respectively;meanwhile, the areas of influence for carcinogenic risk resulting from WBP emission sources were 1.2 and 2.3 times greater than those measured on fine and rainy days, respectively, and 1.8 and 2.9 times greater for SBP emission sources.Compared with WBPs, the total spans of negatively influenced regions resulting from SBP emission sources were 10.4, 12.5 and 19.9 times greater on fine, rainy and heavypolluting days, respectively.Therefore, carcinogenic risk was the dominant health threat for populations residing close to solvent-consuming industrial emission sources.The findings suggest that newly developed solvents are capable of significantly reducing consequent health threats, nevertheless, they could still pose occasional threats to nearby residents under specific meteorological conditions.

关键词： Secondary receptor spatial distribution Solvent-consuming emission source Potential health risk Acquirable risk-free region

Activity-density and spatial distribution of termites on a fine-scale in a tropical rainforest in Xishuangbanna,southwest China

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Soil Ecology Letters 2023年第1期5卷 169-180页

作者： Myo Thant Xiaobing Lin Anjana JAtapattu Min Cao Shang-wen Xia Shengjie Liu Xiaodong Yang CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesXishuangbanna 666303China University of Chinese Academy of Sciences Beijing 100049China Forest Department Ministry of Natural Resources and Environmental ConservationNay Pyi TawMyanmar Jiangxi Institute of Red Soil Nanchang 331717China Agronomy Division Coconut Research InstituteLunuwila 61150Sri Lanka State Key Laboratory of Biocontrol School of Life Sciences and School of EcologySun Yat-sen UniversityGuangzhou 510275China

The community composition and activity-density of termites can influence nutrient cycling and other ecological functions.However,the spatial distribution and the activity-density of termites on a fine-scale in tropical forests are still unknown.We checked the spatial distribution patterns of the feeding groups and species of termites and their co-occurrence pattern in a 1-ha(100 m×100 m)plot,and their correlatiion with the environmental factors.We used a standard protocol to collect termite assemblages and classified them into five feeding groups based on their preferrred diet:fungus growers,litter feeders,soil feeders,soil-wood feeders,and wood feeders.We measured the environmental factors:soil pH,litter mass,aboveground plant biomass,and topographic position index(TPI).Soil-wood feeders showed the highest activity-density,followed by wood feeders,fungus growers,soil feeders,and litter feeders.Soil-wood feeders and fungus growers demonstated a strong correlation while litter feeders showed weak correlations with other feeding groups.Termite feeding groups and most of the termite species displayed a positive association with the high TPI and the low soil pH patches.Our results indicated that the examined environmental factors influenced the termite community assemblages and distribution patterns on a fine-scale in tropical rainforests.

关键词： Competition Co-occurrence Feeding groups Fine-scale spatial distribution Tropical rainforest

spatial distribution of IL4 controls iNKT cell-DC crosstalk in tumors

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Cellular & Molecular Immunology 2020年第5期17卷 496-506页

作者： Lu Wang Zhilan Liu Lili Wang Qielan Wu Xiang Li Di Xie Huimin Zhang Yongdeng Zhang Lusheng Gu Yanhong Xue Ting Yue Gang Liu Wei Ji Haiming Wei Tao Xu Li Bai Division of Life Sciences and Medicine Department of Oncology of The First Affiliated HospitalThe CAS Key Laboratory of Innate Immunity and Chronic DiseaseUniversity of Science and Technology of China230027 HefeiChina National Key Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of Sciences100101 BeijingChina School of Life Sciences University of Science and Technology of China230027 HefeiChina National Synchrotron Radiation Laboratory University of Science and Technology of China230027 HefeiChina

The spatiotemporal distribution of cytokines orchestrates immune responses in vivo,yet the underlying mechanisms remain to be explored.We showed here that the spatial distribution of interleukin-4(IL4)in invariant natural killer T(iNKT)cells regulated crosstalk between iNKT cells and dendritic cells(DCs)and controlled iNKT cell-mediated T-helper type 1(Th1)responses.The persistent polarization of IL4 induced by strong lipid antigens,that is,α-galactosylceramide(αGC),caused IL4 accumulation at the immunological synapse(IS),which promoted the activation of the IL4R-STAT6(signal transducer and activator of transcription 6)pathway and production of IL12 in DCs,which enhanced interferon-γ(IFNγ)production in iNKT cells.Conversely,the nonpolarized secretion of IL4 induced by Th2 lipid antigens with a short or unsaturated chain was incapable of enhancing this iNKT cell-DC crosstalk and thus shifted the immune response to a Th2-type response.The nonpolarized secretion of IL4 in response to Th2 lipid antigens was caused by the degradation of Cdc42 in iNKT cells.Moreover,reduced Cdc42 expression was observed in tumorinfiltrating iNKT cells,which impaired IL4 polarization and disturbed iNKT cell-DC crosstalk in tumors.

关键词： spatial distribution Polarization IL4 iNKT DC Crosstalk Tumor

spatial distribution analysis of landslides triggered by the 2013-04-20 Lushan earthquake,China

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Earthquake Engineering and Engineering Vibration 2016年第1期15卷 163-171页

作者： Chang Ming Tang Chuan Xia Chenhao Fang Qunsheng State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection Chengdu University of Technology

The 2013-04-20 Lushan earthquake（seismic magnitude Ms 7.0 according to the State Seismological Bureau）induced a large number of landslides.In this study,spatial characteristics of landslides are developed by interpreting digital aerial photography data.Seven towns near the epicenter,with an area of about 11.11 km2,were severely affected by the earthquake,and 703 landslides were identified from April 24,2013 aerial photography data over an area of 1.185 km2.About 55.56% of the landslide area was less than 1000 m2,whereas about 3.23 % was more than 10,000 m2.Rock falls and shallow landslides were the most commonly observed types in the study area,and were primarily located in the center of Lushan County.Most landslide areas were widely distributed near river channels and along roads.Five main factors were chosen to study the distribution characteristics of landslides：elevation,slope gradients,fault,geologic unit and river system.The spatial distribution of coseismal landslides is studied statistically using both landslide point density（LPD）,defined as the number of landslides（LS Number）per square kilometer,and landslide area density（LAD）,interpreted as the percentage of landslides area affected by earthquake.The results show that both LPD and LAD have strong positive correlations with five main factors.Most landslides occurred in the gradient range of 40°-50° and an elevation range of 1.0-1.5 km above sea level.Statistical results also indicate that landslides were mainly formed in soft rocks such as mudstone and sandstone,and concentrated in IX intensity areas.

关键词： Lushan earthquake landslide spatial distribution impact factor

spatial distribution of heavy metals of agricultural soils in Dongguan, China

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Journal of Environmental Sciences 2004年第6期16卷 912-918页

作者： XIAYun-sheng LIFang-bai WANHong-fu MAJin YANGGuo-yi ZHANGTian-bin LUOWei GuangdongInstituteofEco-EnvironmentandSoilSciences GuangdongKeyLaboratoryofIntegratedControlofAgrn~EnvironmentGuangzhou510650China.

distribution and speciation of heavy metals of agricultural soils(85 surface soil samples and 4 soil profiles) in Dongguan were investigated, while total Cr, Cu, Ni, Pb, Zn(abbreviated as Cr, Cu, Ni, Pb, Zn) and available Cu, Zn(Av-Cu, Av-Zn) were analyzed by a flame absorption spectrophotometer(AAS), and total Cd(Cd) was analyzed using graphite furnace AAS. The content of Cd, Cu and Ni was partially much more than the second grade of GB15618-1995 even though the mean contents of all heavy metal were less than the threshold value of the second grade and only the mean content of Pb was more than the value of national background. Results of descriptive statistic showed that the mean content of heavy metals should depend on land utilization and spatial location at some extent. The heavy metal contents were higher in the Southwest and Northwest than in the Central. In addition, the mean contents of Zn and Pb in Dongguan paddy soils were significantly higher than those of Pearl River Delta(PRD) and Taihu Lake region(TLR). Correlation analyses indicated that there existed significant correlation between Cr and Ni in orchard soils, and among Zn, Cd and Cu, between Av-Cu and Cu, between Av-Zn and Cr, Ni, pH value in vegetable soils, and a weak relationship between Cd, Cu and Pb, between Av-Zn and Zn. Principal component analyses(PCA) showed that the order of importance should be Zn>Pb>Cr>Ni>Cu.

关键词： heavy metal spatial distribution agricultural soil Dongguan

Molecular evolution,virology and spatial distribution of HCV genotypes in Pakistan:A meta-analysis

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Infectious Medicine

Infectious Medicine 2023年第4期2卷 324-333页

作者： Arslan Habib Nadiya Habib Khalid Mahmood Anjum Riffat Iqbal Zeeshan Ashraf Muhammad Usman Taj Muhammad Asim Kanwal Javid Faezeh Idoon Saeid Dashti Cassio Rocha Medeiros Ana Pavla Almeida Diniz Gurgel Henrique Douglas Melo Coutinho Laboratory of Molecular Immunology School of Life SciencesFudan UniversityShanghai 200433China Department of Zoology University of GujratGujratPunjab 50700Pakistan Department of Zoology University of Veterinary and Animal SciencesLahore 54000Pakistan Department of Zoology Government College UniversityLahore 54000Pakistan Department of Fisheries and Aquaculture University of Veterinary and Animal SciencesLahore 54000Pakistan Department of Zoology University of NarowalNarowal 51600Pakistan Department of Geography Government College UniversityLahore 54000Pakistan Department of Surgical Technology Ferdows School of Allied Medicine and Public HealthBirjand University of Medical SciencesBirjand 97178Iran Ferdows School of Paramedical and Health Birjand University of Medical SciencesBirjand 97178Iran CECAPE College Juazeiro do Norte 63024-015Brazil Department of Engineering and Environment Federal University of ParaibaJoão Pessoa 58051-900Brazil Laboratory of Microbiology and Molecular Biology(LMBM) Department of Biological ChemistryRegional University of CaririCrato 63105-000Brazil

Background:Hepatitis C,caused by the Hepatitis C Virus(HCV),is the second most common form of viral hepatitis.The geographical distribution of HCV genotypes can be quite complex,making it challenging to ascertain the most prevalent genotype in a specific area.Methods:To address this,a review was conducted to determine the prevalence of HCV genotypes across various provinces and as a whole in Pakistan.The scientific literature regarding the prevalence,distribution,genotyping,and epidemiology of HCV was gathered from published articles spanning the years 1996-2020.Results:Genotype 1 accounted for 5.1%of the patients,with its predominant subtype being 1a at 4.38%.The frequencies of its other subtypes,1b and 1c,were observed to be 1.0%and 0.31%respectively.Genotype 2 had a frequency of 2.66%,with the most widely distributed subtype being 2a at 2.11%of the patients.Its other subtypes,2b and 2c,had frequencies of 0.17%and 0.36%respectively.The most prevalent genotype among all isolates was 3(65.35%),with the most frequent subtype being 3a(55.15%),followed by 3b(7.18%).The prevalence of genotypes 4,5,and 6 were scarce in Pakistan,with frequencies of 0.97%,0.08%,and 0.32%respectively.The prevalence of untypeable and mixed genotypes was 21.34%and 3.53%respectively.Estimating genotypes proves to be a productive method in assisting with the duration and selection of antiviral treatment.Different HCV genotypes can exhibit variations in their response to specific antiviral treatments.Different genotypes may have distinct natural histories,including variations in disease progression and severity.Some genotypes may lead to more rapid liver damage,while others progress more slowly.Conclusions:This information can guide screening and testing strategies,helping to identify individuals at higher risk of developing severe complications.Studying the distribution of HCV genotypes in a population can provide valuable insights into the transmission dynamics of the virus.

关键词： Genotypes HCV Molecular evolution Pakistan spatial distribution