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Infectious Disease Modelling 2020年第1期5卷 362-365页

作者： Gerry F.Killeen School of Biological Earth&Environmental Sciencesand Environmental Research InstituteUniversity College CorkIreland

Countries with ambitious national strategies to crush the curve of their Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)epidemic trajectories include China,Korea,Japan,Taiwan,New Zealand and Australia.However,the United States and many hard-hit European countries,like Ireland,Italy,Spain,France and the United Kingdom,currently appear content to merely flatten the curve of their epidemic trajectories so that transmission persists at rates their critical care services can cope with.Here I present a simple set of arithmetic modelling analyses that are accessible to non-specialists and explain why preferable crush the curve strategies,to eliminate transmission within months,would require only a modest amount of additional containment effort relative to the tipping point targeted by flatten the curve strategies,which allow epidemics to persist at supposedly steady,manageable levels for years,decades or even indefinitely.

关键词： Coronavirus COVID SARS2 Severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 Model Epidemiology Outbreak Zoonosis Emerging infection

人类活动改变了中亚1000年以来的火-气候关系:来自4200年的沉积物记录

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Science Bulletin 2021年第8期66卷 761-764,M0003页

作者：张山佳鲁轶文魏文钰仇梦晗董广辉刘兴起 College of Earth&Environmental Sciences Lanzhou UniversityLanzhou 730000China Center for Excellence in Tibetan Plateau earth sciences Chinese Academy of SciencesBeijing 100101China college of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China

火灾深刻地影响着人类的生产生活.中亚地区对气候变化响应敏感且有着悠久的放牧活动历史,然而由于缺乏高分辨率的火灾记录,该地区长时间尺度的火-气候-人类活动间的关系仍不清楚.本文通过对新疆卡拉库里湖泊(38.439°N, 75.057°E;3645 ... 详细信息

火灾深刻地影响着人类的生产生活.中亚地区对气候变化响应敏感且有着悠久的放牧活动历史,然而由于缺乏高分辨率的火灾记录,该地区长时间尺度的火-气候-人类活动间的关系仍不清楚.本文通过对新疆卡拉库里湖泊(38.439°N, 75.057°E;3645 masl)沉积物中的黑碳含量分析,重建了该地区首条高分辨率(~20年)的晚全新世火灾记录.综合古气候记录对比分析表明, 4200~1000 a BP,在年代际、百年际和千年际尺度上,湿润期对应火灾多发期;1000 a BP以来,在百年际和千年际尺度上,湿润期对应火灾少发期.我们认为,中亚地区草原火灾的变化受控于湿度所影响的植被载荷的变化,而人类活动(如牧业和农业)很可能通过减少地表生物量而抑制了近1000年来的火灾活动,打破了长期以来气候控制火灾变化的模式.本研究对以草原为主的中亚地区火-气候-人类活动之间的相互作用提供了有益的认知,有助于未来火灾管理政策的制定.

关键词：草原火灾晚全新世卡拉库里湖气候变化响应长时间尺度中亚地区高分辨率

Why lockdown?Why national unity?Why global solidarity?Simplified arithmetic tools for decision-makers,health professionals,journalists and the general public to explore containment options for the 2019 novel coronavirus

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Infectious Disease Modelling 2020年第1期5卷 442-458页

作者： Gerry F.Killeen Samson S.Kiware environmental Health and Ecological sciences Department Ifakara Health InstituteIfakaraMorogoroUnited Republic of Tanzania School of Biological Earth&Environmental Sciences and Environmental Research InstituteUniversity College CorkIreland

As every country in the world struggles with the ongoing COVID-19 pandemic,it is essential that as many people as possible understand the epidemic containment,elimination and exclusion strategies required to tackle it.Simplified arithmetic models of COVID-19 transmission,control and elimination are presented in user-friendly Shiny and Excel formats that allow non-specialists to explore,query,critique and understand the containment decisions facing their country and the world at large.Although the predictive model is broadly applicable,the simulations presented are based on parameter values representative of the United Republic of Tanzania,which is still early enough in its epidemic cycle and response to avert a national catastrophe.The predictions of these models illustrate(1)why ambitious lock-down interventions to crush the curve represent the only realistic way for individual countries to contain their national-level epidemics before they turn into outright catastrophes,(2)why these need to be implemented so early,so stringently and for such extended periods,(3)why high prevalence of other pathogens causing similar symptoms to mild COVID-19 precludes the use of contact tracing as a substitute for lock down interventions to contain and eliminate epidemics,(4)why partial containment strategies intended to merely flatten the curve,by maintaining epidemics at manageably low levels,are grossly unrealistic,and(5)why local elimination may only be sustained after lock down ends if imported cases are comprehensively excluded,so international co-operation to conditionally re-open trade and travel between countries certified as free of COVID-19 represents the best strategy for motivating progress towards pandemic eradication at global level.The three sequential goals that every country needs to emphatically embrace are contain,eliminate and exclude.As recently emphasized by the World Health Organization,success will require widespread genuine national unity and unprecedented global solidarity.

关键词： Coronavirus COVID-19 SARS2 Severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 Model Epidemiology Outbreak Zoonosis Emerging infection

Detecting anthropogenic impact on forest succession from the perspective of wood exploitation on the northeast Tibetan Plateau during the late prehistoric period

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Science China earth sciences 2022年第11期65卷 2068-2082页

作者： Fengwen LIU Shanjia ZHANG Hucai ZHANG Guanghui DONG Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environment ScienceYunnan UniversityKunming 650504China Ministry of Education Key Laboratory of Western China's environmental System College of Earth&Environmental SciencesLanzhou UniversityLanzhou 730000China

Human activities are usually considered to have had impacts on forest degradation and/or changes of forest composition in the past.The Tibetan Plateau,an environmentally sensitive area,has witnessed a high intensity of human activities since the late Neolithic,but the evidence is still incomplete concerning how human activities affected the environment,especially vegetation changes.This may result,in part,from the fact that research on prehistoric wood utilization by humans in the northeast Tibetan Plateau(NETP)is scarce,especially from the perspective of charcoal analysis,which is an archaeological index directly related to human activities.To fill this gap,we report new data here concerning charcoal analysis from 24 archaeological sites dated 5200–2300 a BP in the NETP,where this period saw remarkable environmental and social changes.By coupling the results with published paleoenvironment records(especially pollen),we aim to explore the utilization of wood and its spatial-temporal changes,as well as the anthropogenic impacts on past forest dynamics in the NETP.The results suggest that the wood resources collected by humans were mainly needleleaf trees(Picea L.and Pinus L.),broadleaved trees(Populus L.,Salix L.,and Betula)as well as shrubs(Hippophae L.and Tamarix L.),and that these were distributed around the human habitation areas.There was a clear spatial difference in the woody assemblage collected by humans in the period 3600–2300 a BP.This was likely related to the diversity of natural environments in local areas,but there was an abnormal spatial pattern of forest composition with broadleaved trees dominant above 2500 masl caused not by climate change,but by the rapid increase of human settlement and wood collection in high altitude areas of the NETP since 3600 a BP.

关键词： Charcoal records Late prehistoric period Northeast Tibetan Plateau Climate change Anthropogenic impacts

Long, thin transmission chains of Severe Acute Respiratory Syndrome Coronavirus 2 may go undetected for several weeks at low to moderate reproduction numbers: Implications for containment and elimination strategy

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Infectious Disease Modelling 2021年第1期6卷 474-489页

作者： Gerry F.Killeen Patricia M.Kearney Ivan J.Perry Niall Conroy School of Biological Earth&Environmental SciencesUniversity College CorkCorkIreland environmental Research Institute University College CorkCorkIreland School of Public Health University College CorkCorkIreland Wide Bay Public Health Unit QueenslandAustralia Faculty of Medicine University of QueenslandBrisbaneQueenslandAustralia

Severe Acute Respiratory Syndrome Coronavirus 1(SARS-CoV-1)infections almost always caused overt symptoms,so effective case and contact management enabled its effective eradication within months.However,Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)usually causes only mild symptoms,so transmission chains may grow to include several individuals before at least one index case becomes ill enough to self-report for diagnosis and care.Here,simple mathematical models were developed to evaluate the implications of delayed index case detection for retrospective contact tracing and management responses.Specifically,these simulations illustrate how:(1)Contact tracing and management may effectively contain most but not all large SARS-CoV-2 clusters arising at foci with high reproduction numbers because rapidly expanding transmission chains ensure at least one overtly symptomatic index case occurs within two viral generations a week or less apart.(2)However,lower reproduction numbers give rise to thinner transmission chains extending through longer sequences of non-reporting asymptomatic and paucisymptomatic individuals,often spanning three or more viral generations(2 weeks of transmission)before an overtly symptomatic index case occurs.(3)Consequently,it is not always possible to fully trace and contain such long,thin transmission chains,so the community transmission they give rise to is underrepresented in surveillance data.(4)Wherever surveillance systems are weak and/or transmission proceeds within population groups with lower rates of overt clinical symptoms and/or self-reporting,case and contact management effectiveness may be more severely limited,even at the higher reproduction numbers associated with larger outbreaks.(5)Because passive surveillance platforms may be especially slow to detect the thinner transmission chains that occur at low reproduction numbers,establishing satisfactory confidence of elimination may require that no confirmed cases are detected for two full months,throughout which presump

关键词： Coronavirus COVID SARS2 Severe Acute Respiratory Syndrome Coronavirus 2 SARS-CoV-2 Model Epidemiology Outbreak Case and contact management

Refined chronology of prehistoric cultures and its implication for re-evaluating human-environment relations in the Hexi Corridor,northwest China

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Science China earth sciences 2019年第10期62卷 1578-1590页

作者： Yishi YANG Shanjia ZHANG Chris OLDKNOW Menghan QIU Tingting CHEN Haiming LI Yifu CUI Lele REN Guoke CHEN Hui WANG Guanghui DONG Gansu Provincial Institute of Cultural Relics and Archaeology Lanzhou730000China MOE Key Laboratory of Western China抯environmental Systems College of Earth&Environmental SciencesLanzhou UniversityLanzhou730000China History and Culture School Lanzhou UniversityLanzhou730000China CAS Center for Excellence in Tibetan Plateau earth sciences Chinese Academy of Sciences(CAS)Beijing100101China

The reconstruction of high-resolution chronologies for prehistoric cultures is a prerequisite for understanding the history of human evolution and its relationship with environmental change, and is valuable for exploring the trajectory of transcontinental cultural exchanges in prehistoric time. The Hexi Corridor of northwest China was one of the earliest centers for long-distance culture exchange in the prehistoric world. The timing and sequence of cultural changes in this area remains poorly understood resulting from the lack of radiometric age control. This paper presents a refined radiocarbon(14 C) chronology to resolve the timing of human occupation and cultural evolution in the Hexi Corridor. Radiocarbon dating of crop remains, which have an annual life cycle, has the advantage of eliminating problems such as the carbon stored in ‘old wood’. As a result,14C dates from crop remains are used to test the validity of the14C dates derived from charcoal, bone and plant remains. The resultant database of ages is modelled using the Bayesian approach. The updated chronology presented in this paper shows generally good agreement with the original dates used to constrain cultural evolution in the Hexi Corridor. However, the occupation of the corridor by the Shajing and Shanma Late Bronze Age-Early Iron Age cultures appears to have taken place ~300 years later than previously thought. On the basis of comparing this updated chronology of cultural evolution with palaeoclimatic and historical records, it is proposed that the collapse of the Shajing and Shanma cultures occurred as a result of geopolitical impact rather than climate change.

关键词： Bayesian modelling Radiocarbon dating Neolithic and Bronze Age Chronology Geopolitical situation Climate change Hexi Corridor

Quantitative studies on charcoalification:Physical and chemical changes of charring wood

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Fundamental Research 2024年第1期4卷 113-122页

作者： Gang Li Linlin Gao Fengwen Liu Menghan Qiu Guanghui Dong MOE Key Laboratory of Western China's environmental Systems College of Earth&Environmental SciencesLanzhou UniversityLanzhou 730000China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environment ScienceYunnan UniversityKunming 650504China

Charcoal is commonly preserved in both natural and artificial sediments,and is intensively used in paleontological,paleoenvironmental,and archaeological studies due to the abundant bio-information it contains.The biochemical properties of charcoal are also used for paleoclimatic reconstruction;however,the reliability of this approach has been challenged due to a lack of clarity on how physicochemical properties change during the charring process,as well as the temperatures required for charcoalification.To address this lack,in this study,Qinghai spruce and Chinese pine wood samples from the northeastern Tibetan Plateau were heated at different temperatures and for different lengths of time under restricted oxygen conditions.The reflectance;carbon,nitrogen,and oxygen content;and tracheid morphology were quantified before and after heating to assess changes related to the charring process.Archaeological charcoal remains were then evaluated to determine the charcoalification temperatures by comparing with the experimental results.The minimum temperature required for wood charcoalification was∼300℃,while temperatures recorded by archaeological charcoal were concentrated at 400-500℃.During the charring experiments,the tracheid cell walls gradually homogenized,and tracheid cell wall thickness and lumen area decreased by∼20%.On average,50%mass losses were observed;the carbon and oxygen content(%wt.)approximately changed from 47%to 60%and 48%to 35%respectively,while the nitrogen content(%wt.)fluctuated around 0.2%.The reflectance increased slightly from 0%to 0.5%.We propose that the charcoalification of wood tissue refers to charring(in restricted air)and carbonization(in the almost absence of air)when the wood is exposed to a heat source,which then finally transforms into a black,inert solid.This quantitative study provided valuable data and a thorough assessment of the process of wood charcoalification,as well as accurately estimated the feasibility of using charcoal physicochemical properties in paleoclimatic research

关键词： Charcoalification Quantitative study Charcoal formation Archaeological charcoal Tracheid cell wall thickness Reflectance

Silurian Sedimentation in the South Qilian Belt: Arc-Continent Collision-related Deposition in the NE Tibet Plateau?

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 901-913页

作者： YAN Zhen FU Changlei Jonathan CAITCHISON ZHOU Renjie Solomon BUCKMAN CHEN Lei Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of earth and environmental sciences University of QueenslandBrisbaneQueensland4072Australia School of earth&environmental Science University of WollongongNSW 2522Australia

The South Qilian belt mainly comprises an early Paleozoic arc-ophiolite complex, accretionary prism, microcontinental block, and foreland basin. These elements represent accretion-collision during Cambrian to Silurian time in response to closure of the Proto-Tethyan Ocean in the NE of the present-day Tibet Plateau. Closure of the Proto-Tethyan Ocean between the Central Qilian block and the Oulongbuluke block and the associated collision took place from NE to SW in a zipper-like style. Sediment would have been dispersed longitudinally SW-ward with a progressive facies migration from marginal alluvial sediments toward slope deep-water and deep-sea turbidites. This migration path indicates an ocean basin that shrank toward the SW. The Balonggongga'er Formation in the western South Qilian belt represents the fill of a latest Ordovician-Silurian remnant ocean basin that separated the Oulongbuluke block from the Central Qilian block, and records Silurian closure of the Proto-Tethyan Ocean and subduction beneath the Central Qilian block. However, alluvial deposits in the Lajishan area were accumulated in a retro-foreland basin, indicating that continent-continent collision in the eastern South Qilian belt occurred at c. 450–440 Ma. These results demonstrate that the Proto-Tethyan Ocean closed diachronously during early Paleozoic time.

关键词： remnant ocean basin Qilian Orogen arc-continental collision Proto-Tethyan Ocean

燃烧源氨排放对灰霾期间北京大气铵的重要贡献

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Science Bulletin 2024年第7期69卷 978-987页

作者：吴礼彬王芃张强任红 Zongbo Shi 胡伟陈静谢巧蓉李林杰越思瑶韦莲芳宋琳琳张永根王子涵陈爽韦琬王小曼章炎麟孔少飞葛宝珠杨婷方运霆任露洁邓君俊孙业乐王自发张宏亮胡建林刘丛强 Roy M.Harrison Qi Ying 傅平青 Institute of Surface-earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Department of Atmospheric and Oceanic sciences Fudan UniversityShanghai 200438China IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200438China Ministry of Education Key Laboratory for earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China Air environmental Modeling and Pollution Controlling Key Laboratory of Sichuan Higher Education Institute Chengdu University of Information TechnologyChengdu 610225China Division of environmental Health&Risk Management School of GeographyEarth&Environmental SciencesUniversity of BirminghamBirmingham B152TTUK School of environmental Science and Engineering Tianjin UniversityTianjin 300072China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China Yale-NUIST Center on Atmospheric Environment International Joint Laboratory on Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric sciences School of Environmental Studies and Department of Environmental Science and TechnologySchool of Environmental StudiesChina University of GeosciencesWuhan 430074China Department of environmental Science and Engineering Fudan UniversityShanghai 200438China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlNanjing University of Information Science and TechnologyNanjing 210044China Department of environmental sciences/Center of Excellence in environmental Studies King Abdulaziz UniversityJeddah 21589Saudi Arabia Zachr

Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and formation mechanism of NH_(4)^(+)can provide scientific insights into air quality improvements.However,the sources of NH_(3)in urban areas are not well understood,and few studies focus on NH_(3)/NH_(4)^(+)at different heights within the atmospheric boundary layer,which hinders a comprehensive understanding of aerosol NH_(4)^(+).In this study,we perform both field observation and modeling studies(the Community Multiscale Air Quality,CMAQ)to investigate regional NH_(3)emission sources and vertically resolved NH_(4)^(+)formation mechanisms during the winter in Beijing.Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH_(3)emissions,including fossil fuel sources,NH_(3)slip,and biomass burning,are important sources of aerosol NH_(4)^(+)with more than 60%contribution occurring on heavily polluted days.In contrast,volatilization-related NH_(3)sources(livestock breeding,N-fertilizer application,and human waste)are dominant on clean days.Combustion-related NH_(3)is mostly local from Beijing,and biomass burning is likely an important NH_(3)source(~15%–20%)that was previously overlooked.More effective control strategies such as the two-product(e.g.,reducing both SO_(2)and NH_(3))control policy should be considered to improve air quality.

关键词： Particulate ammonium Nitrogen isotope PM2.5 The Community Multiscale Air Quality(CMAQ) Control policy

Groundwater recharge site suitability analysis through multiinfluencing factors(MIF)in West Bengal dry-land areas,West Bengal,India

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Acta Geochimica 2022年第6期41卷 1030-1048页

作者： Kartic Bera Michelle E.Newcomer Pabitra Banik Agricultural and Ecological Research Unit Indian Statistical Institute203Barrackpore Trunk RoadKolkataWest Bengal700108India Lawrence Berkeley National Laboratory Earth&Environmental Sciences AreaBerkeleyCAUSA

Groundwater levels are gradually declining in basins around the world due to anthropogenic and natural factors.Climate is not the only factor contributing to change in groundwater levels,population growth and economic progress are leading to increased water demand.Areas used for agricultural irrigation are expanding,necessitating the use of artificial groundwater recharge as a method to sustain pumping and enhance storage.The present study delineates potential locations of significant groundwater resources that already exist using a geostatistical approach as a method to identify potential groundwater recharge zones.The Multi-Influencing Factors(MIF)technique was applied to determine the relationship between different landscape and climatic factors that influence groundwater recharge.Factors include topography,climate,hydrogeology,population,economic change,and geology.Integration of these factors enabled the identification of potential locations of groundwater suitable for artificial recharge efforts based on weights derived through the MIF technique.We applied these weights to derive a groundwater recharge index(GRI)map.The map was delineated into three groundwater recharge zones classified by their potential areal coverage as a metric for recharge suitability,namely low,medium and high suitability,occupying areas of 8625 km2(30.06%),9082 km2(31.65%),and 10,989 km~2(38.29%),respectively.Our findings have important implications for designing sustainable groundwater development and land-use plans for the coming century.

关键词： Dry-lands Multi-influencing factor(MIF) Weighted index overlay(WIO) Groundwater suitable for artificial recharge(GSAR) Recharge volume(RV)