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Fungal spore record of pastoralism on the NE Qinghai-Tibetan Plateau since the middle Holocene

Science China Earth Sciences 2021年第8期64卷 1318-1331页

作者： haicheng wei Chongyi E Ronglei DUAN Jing ZHANG Yongjuan SUN Guangliang HOU Jingyi GAO Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Physical Geography and Environmental Processes School of Geographic ScienceQinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810008China

Pastoralism is considered a crucial factor in the eventual year-round occupation of high-altitude regions(>3000 m asl)of the Qinghai-Tibetan Plateau,and the northeastern Qinghai-Tibetan Plateau(NE-QTP)was an important corridor for early human occupation.We analyzed fossil fungal spore records for the last 8500 years from a high resolution aeolian section at Langgeri(LGR)on the NE-QTP.Thirty-two fungal spore types were identified in the LGR section,including seven coprophilous types.We combined analysis of coprophilous fungal spores,Cyperaceae,Artemisia,and Hippophae pollen,and the charcoal>50µm fraction to explore the timing and controls of pastoralism on the NE-QTP since the middle Holocene.Pastoralism commenced at LGR shortly before ca.5.5 ka and gradually increased between ca.5.5–3.5 ka,but markedly intensified after ca.2.2 ka,with three periods of growth at ca.2.1–1.9,1.4–1.2,and 0.6–0 ka,and a decline at ca.1.1–0.6 ka.The timing of changes in pastoral activity on the NE-QTP based on the coprophilous fungal spore record is supported by regional archeology and historical documents.Technological and political developments,rather than climate change,played key roles in the long-term fluctuations of regional pastoralism on the NE-QTP in the late Holocene.

关键词： Coprophilous fungal spores Pastoralism Qinghai Lake basin Holocene Qinghai-Tibetan Plateau

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Optical and scintillation properties of Bi_4Si_3O_(12):RE(RE=Eu^(3+), Sm^(3+),Ho^(3+), Tb^(3+))single crystals

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Journal of Rare Earths 2019年第3期37卷 260-264页

作者： Xuefeng Xiao Jiayue Xu haicheng wei Yaoqing Chu Bobo Yang Xuefeng Zhang Key Laboratory of Physics and Photoelectric Information Functional Materials Sciences and Technology North Minzu University College of Electric and Information Engineering North Minzu University School of Materials Science and Engineering Tongji University School of Materials Science and Engineering Shanghai Institute of Technology Ningxia Ju Jing Yuan Crystal Technology Company Limited

Bi_4 Si_3 O_(12):RE(BSO:RE, RE = Eu^(3+), Sm^(3+), Ho^(3+), Tb^(3+)) crystals were grown by the modified vertical Bridgeman method, and doping effects on scintillation properties were investigated. Under γ-ray irradiation, the light yield of BSO doped with small doses of Eu^(3+) increases slightly, and the energy resolution improves significantly compared to pure BSO, therefore the ability of distinguishing between particles will be improved for BSO crystals with a small amount of Eu^(3+) dopant. The results show that a small amount of Eu^(3+) doping can sensitize the Bi^(3+) ions. The sensitization effect enables the reduction of intrinsic defects, and thus improves the scintillation properties. However, the relative light yield of BSO:Tb(1.0 mol%) crystal is 4.3%, which is smaller than 5.0% of pure BSO. The improved light yield and energy resolution in the BSO:Eu and BSO:Sm crystals are considered an impressive achievement in the optimization of this scintillator which is already suitable for applications such as dual-readout calorimeters and homogeneous hadron calorimeters.

关键词： BSO crystal Vertical Bridgeman method Scintillation characteristics Relative light yield Rare earths

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Characterization of the retinal vasculature in fundus photos using the PanOptic iExaminer system

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Eye and Vision 2020年第2期7卷 444-453页

作者： Huiling Hu haicheng wei Mingxia Xiao Liqiong Jiang Huijuan Wang Hong Jiang Tatjana Rundek Jianhua Wang Shenzhen Key Laboratory of Ophthalmology Shenzhen Eye HospitalJinan UniversityShenzhenChina Department of Ophthalmology Bascom Palmer Eye InstituteUniversity of Miami Miller School of Medicine1638 NW 10th AvenueMcKnight Building-Room 202AMiamiFL 33136USA Department of Electrical and Computer Engineering Florida International UniversityMiamiFLUSA School of Electrical and Information Engineering North Minzu UniversityYinchuanNingxiaChina Eye hospital China Academy of Chinese Medical SciencesBeijingChina Department of Neurology University of Miami Miller School of MedicineMiamiFLUSA

Background:The goal was to characterize retinal vasculature by quantitative analysis of arteriole-to-venule(A/V)ratio and vessel density in fundus photos taken with the PanOptic iExaminer System.Methods:The PanOptic ophthalmoscope equipped with a smartphone was used to acquire fundus photos centered on the optic nerve head.Two fundus photos of a total of 19 eyes from 10 subjects were imaged.Retinal vessels were analyzed to obtain the A/V ratio.In addition,the vessel tree was extracted using deep learning U-NET,and vessel density was processed by the percentage of pixels within vessels over the entire image.Results:All images were successfully processed for the A/V ratio and vessel density.There was no significant difference of averaged A/V ratio between the first(0.77±0.09)and second(0.77±0.10)measurements(P=0.53).There was no significant difference of averaged vessel density(%)between the first(6.11±1.39)and second(6.12±1.40)measurements(P=0.85).Conclusions:Quantitative analysis of the retinal vasculature was feasible in fundus photos taken using the PanOptic ophthalmoscope.The device appears to provide sufficient image quality for analyzing A/V ratio and vessel density with the benefit of portability,easy data transferring,and low cost of the device,which could be used for pre-clinical screening of systemic,cerebral and ocular diseases.

关键词： Smartphone ophthalmoscope Image analysis Deep learning Arteriovenous ratio Vessel density Retina

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Evaluation of boron isotopes in halite as an indicator of the salinity of Qarhan paleolake water in the eastern Qaidam Basin, western China

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Geoscience Frontiers 2019年第1期10卷 253-262页

作者： Yongsheng Du Qishun Fan Donglin Gao haicheng wei Fashou Shan Binkai Li Xiangru Zhang Qin Yuan Zhanjie Qin Qianhui Ren Xueming Teng Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Key Laboratory of Salt Lake Geology and Environment of Qinghai Province University of Chinese Academy of Sciences Tianjin Center China Geological Survey

In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western China were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isotopic compositions. The B concentrations and δ^(11) B values of brines in the QSL range from 51.6 mg/L to138.4 mg/L, and from +9.32& to +13.08&, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, p H values and δ^(11) B values of brines, previously elemental ratios(K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ^(11) B values of halite from a sediment core(ISL1 A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ^(11) B values of brines, which demonstrate that higher B concentrations and more positive δ^(11) B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ^(11) B values of halite in core ISL1 A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46-34 ka and26-9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1 A,drier climate phases documented from the δ^(18) O record of carbonate in core ISL1 A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ^(11) B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions.

关键词： B isotope compositions Brine Chemical concentrations Qarhan salt lake Western China Salinity of paleolake water

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柴达木盆地可鲁克湖沉积物表层花粉散布规律及其对区域植被的指示意义

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盐湖研究 2024年第1期32卷 66-75页

作者：李鸿宇魏海成成艾颖樊启顺段荣蕾中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室青海西宁810008 中国科学院大学北京100049 青海省海西蒙古族藏族自治州盐湖管理局青海德令哈817000

可鲁克湖是柴达木盆地东部荒漠区重要的生态屏障,对全球气候变化响应十分敏感。利用沉积物化石花粉重建湖泊生态系统演变历史及其对全球气候变化响应过程和机制的分析是当前重要的研究方向,本研究系统采集了可鲁克湖沉积物表层样品开展... 详细信息

可鲁克湖是柴达木盆地东部荒漠区重要的生态屏障,对全球气候变化响应十分敏感。利用沉积物化石花粉重建湖泊生态系统演变历史及其对全球气候变化响应过程和机制的分析是当前重要的研究方向,本研究系统采集了可鲁克湖沉积物表层样品开展花粉分析。研究结果显示,花粉组合以藜科、禾本科、蒿属、莎草科为主。花粉总浓度在湖泊沉积中心及偏西南区域显著偏高,其中藜科、莎草科、蒿属、白刺属、麻黄属、紫菀属花粉与总浓度变化特征较为一致,而禾本科花粉在湖泊东南部显著富集。湖泊沉积物中的藜科和蒿属花粉较好地指示了柴达木盆地东部灌木-矮灌木荒漠和荒漠草原整体植被特征,而禾本科和莎草科花粉主要指示湖岸周边隐域性沼泽和河滩草甸植被群落;白刺属花粉对湖泊北岸一级阶地上的白刺群落发育和湖面变化具有较好的指示意义,谷物类禾本科和十字花科花粉能较为灵敏地反映湖泊附近的农耕活动,桦木属和云杉属花粉则主要由风力和河流远距离输入。研究揭示了可鲁克湖水深、水动力条件、湖岸周围植被群落分布以及风力作用是影响花粉散布和沉积的重要影响因素,此项研究也为青藏高原湖泊沉积物花粉组合的精确解译提供了重要数据资料和分析依据。

关键词：花粉可鲁克湖青藏高原湖泊沉积物柴达木盆地

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铅、锌、镉同位素示踪技术在沉积物重金属污染源解析中的应用:综述与展望

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盐湖研究 2024年第1期32卷 128-138页

作者：高春亮文进心成艾颖闵秀云魏海成中国科学院青海盐湖研究所中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 青海省盐湖地质与环境重点实验室青海西宁810008 中国科学院大学北京100049

沉积物重金属污染防治的关键在于识别其污染源,采用铅、锌、镉多元同位素示踪技术是对其进行污染源解析的最佳手段之一。铅同位素示踪技术较为成熟且应用广泛,锌和镉同位素示踪技术作为新兴技术,在重金属污染源解析研究中可作为有力补... 详细信息

沉积物重金属污染防治的关键在于识别其污染源,采用铅、锌、镉多元同位素示踪技术是对其进行污染源解析的最佳手段之一。铅同位素示踪技术较为成熟且应用广泛,锌和镉同位素示踪技术作为新兴技术,在重金属污染源解析研究中可作为有力补充。本文系统概述了Pb-Zn-Cd同位素的示踪机理、组成特征及其在沉积物重金属污染溯源中的应用,提出未来研究工作的重点是采用多元同位素示踪技术,并结合沉积物形态中重金属稳定同位素的组成示踪污染源。

关键词：铅、锌、镉同位素沉积物重金属污染源解析示踪技术

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青海湖流域高原鼠兔(Ochotona curzoniae)粪花粉和真菌孢子组合及其生态指示意义

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微体古生物学报 2024年第1期41卷 78-92页

作者：侯艺林魏海成鄂崇毅段荣蕾李鸿宇苟华婷青海师范大学地理科学学院西宁810008 中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室西宁810008 中国科学院大学地球与行星科学学院北京100049

高原鼠兔(Ochotona curzoniae)是青藏高原生态系统中的关键物种,是高寒草地生态系统演化过程中的重要组成部分,其对高寒生态系统的影响作用是广泛关注的热点科学问题。本研究采集了青藏高原东北部青海湖流域高寒草甸和温性草原植被群落... 详细信息

高原鼠兔(Ochotona curzoniae)是青藏高原生态系统中的关键物种,是高寒草地生态系统演化过程中的重要组成部分,其对高寒生态系统的影响作用是广泛关注的热点科学问题。本研究采集了青藏高原东北部青海湖流域高寒草甸和温性草原植被群落中的27个高原鼠兔粪样品并开展花粉和真菌孢子分析。结果表明,高原鼠兔粪样品中花粉组合以蒿属、禾本科、莎草科、豆科、菊科、蔷薇科和龙胆科等为主,通过与研究区表土花粉组合对比发现,高原鼠兔的主要食物类型为禾本科和豆科植物,蒿属、莎草科、紫菀属、蔷薇科、蒲公英属和龙胆科等植物也是其少量采食的植物类型。高寒草甸和温性草原植被群落中高原鼠兔粪花粉组合存在一定的差异,表明植物群落组成对高原鼠兔食物的选择产生一定的影响;高原鼠兔粪便真菌孢子组合中荚孢腔菌属占显著优势,是监测高原鼠兔种群密度变化的潜在指示性属种。此外,粪壳菌属、条黑粉菌属、毛壳菌属、格孢腔菌属、Fungi type-1和Fungi type-10也是重要的粪生真菌孢子类型。鼠兔粪样品真菌孢子组合中球囊霉属百分含量较低,指示高原鼠兔对植物根系啃食程度较低。本研究对于深入理解高原鼠兔采食习性,以及对区域植被生态的影响研究提供了重要基础资料,为今后青藏高原草地资源管理、生态恢复治理和高原鼠兔防治策略的制定提供了科学依据。

关键词：高原鼠兔粪花粉真菌孢子生态系统青海湖

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基于SWAT模型的格尔木河上游分布式水文模拟和径流预测

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盐湖研究 2024年第3期32卷 1-10页

作者：易磊陈富洪韩积斌刘小宝杨建文周震鑫卢晓航马喆魏海成韩凤清中国科学院青海盐湖研究所中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 青海省盐湖地质与环境重点实验室青海西宁810008 中国科学院大学北京100049 青海大学三江源生态与高原农牧业国家重点实验室青海西宁810016 青海省海西蒙古族藏族自治州盐湖管理局青海德令哈817099

研究格尔木河流域水文循环过程并预测未来流域水资源的变化特征,对地区生态环境保护和下游盐湖矿产资源可持续开发利用具有重要意义。选取格尔木水文站以上区域构建SWAT(Soil and Water Assessment Tool)分布式水文模型。采用大气同化... 详细信息

研究格尔木河流域水文循环过程并预测未来流域水资源的变化特征,对地区生态环境保护和下游盐湖矿产资源可持续开发利用具有重要意义。选取格尔木水文站以上区域构建SWAT(Soil and Water Assessment Tool)分布式水文模型。采用大气同化数据集为气象驱动,联合区域内纳赤台和格尔木水文站的实测月尺度径流数据进行参数的率定和验证。在率定期和验证期内,纳什效率系数、确定性系数和相对偏差系数均达到了良好的标准,表明SWAT模型在格尔木河高寒山区流域水文过程模拟中具有较好的适用性。研究表明流域降水量偏少,地表径流量、壤中流量与降水量的变化趋势具有较好的一致性,降水量年际变化中蒸散发量为主要消耗量,占40.26%。根据未来气候预测模型RegCM4.6,预测路径浓度RCP2.6、RCP4.5和RCP8.53种情景下格尔木河未来40年径流量呈增加趋势。3种情景下的年平均径流量较基准期(2006—2018年)分别增加了7.63%、11.01%、15.96%;随着温室气体排放浓度的增加,径流量呈现出增加趋势,特别是夏秋季增幅较大。短时间内径流量增大可能会引发格尔木市洪涝灾害,破坏盐湖企业生产设施;但若将洪水资源进行调控和利用,不仅防范了洪涝灾害,同时也利于解决盐湖企业日渐增大的用水需求难题。

关键词：格尔木河上游流域分布式水文模拟 SWAT 未来气候模型径流预测

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Establishment of a TLC Identification Method for Ensete wilsonii

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Plant Diseases and Pests 2024年第1期15卷 4-6页

作者： Yongjing SU Ao XIE Wenwen LIANG Fanglin ZENG haicheng WEN wei wei Guangxi University of Chinese Medicine Nanning 530001China

[Objectives]The paper was to establish a TLC identification method for Ensete wilsonii.[Methods]Usingβ-sitosterol as the reference,the effects of preparation methods of test solutions,developing solvents,developing distances and color developing agents on TLC analysis were investigated,and the best TLC conditions for E.wilsonii were determined.[Results]The test solution prepared with 90%methanol solvent was dotted on TLC silica gel G plate,and developed with dichloromethane-toluene-methanol=10:5:1.5 as the developing solvent.Then the plate was sprayed with 10%sulfuric acid ethanol solution,and dried with hot blast for color development.Finally,the plate was examined under an ultraviolet lamp at 365 nm.The TLC results of E.wilsonii obtained showed good separation and color development effect,and the spots were clear and characteristic.[Conclusions]This method is safe,specific,and easy to operate,and can be used as a TLC identification method for E.wilsonii.

关键词： Ensete wilsonii TLC identification Developing solvent Color developing agent

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A 94-ka Pollen Record of Vegetation Change in Qaidam Basin,Northeastern Qinghai-Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 31-33页

作者： wei haicheng FAN Qishun ZHAO Yan MA Haizhou AN Fuyuan' YUAN Qin CAS Key Laboratory of Salt Lake Resources and Chemistry Qinghai Institute of Salt Lakes Chinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

1 Introduction The northeastern Qinghai-Tibetan Plateau(NE QTP),located at a triple junction of influences of the Asian summer monsoon,westerly jet stream and Siberian high,is of considerable significance with regard ... 详细信息

关键词： Pollen record Climate change Qaidam Basin Late Pleistocene Qinghai-Tibetan Plateau(QTP)

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