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Quantitative analysis of lake area variations and the influence factors from 1971 to 2004 in the Nam Co basin of the Tibetan Plateau

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Chinese Science Bulletin 2010年第13期55卷 1294-1303页

作者： ZHU LiPing xie manping WU YanHong Key Laboratory of Tibetan Environment Changes & Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Digital Earth Sciences Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

By using remote sensing and GIS technologies, spatial analysis and statistic analysis, we calculated the water area and volume variations of the Nam Co Lake from 1971-2004, and discussed their influence factors from the viewpoints of climatic change and water balance. Data source in this study includes bathymetric data of the lake, aerial surveyed topographic maps of 1970, remote sensing images of 1991 and 2004 in the lake catchment, meteorological data from 17 stations within 1971-2004 in the adjacent area of the lake catchment. The results showed that the lake area expanded from 1920 km2 to 2015 km2 during 1971 to 2004 with the mean annual increasing rate (MAIR) of 2.81 km2 a-1, and the lake volume augmented from 783.23×108 m3 to 863.77×108 m3 with the MAIR of 2.37×108 m3. Moreover, the MAIR of the lake area and volume are both higher during 1992 to 2004 (4.01 km2 a-1 and 3.61×108 m3 a-1) than those during 1971 to 1991 (2.06 km2 a-1 and 1.60×108 m3 a-1). Analyses of meteorological data indicated that the continue rising of air temperature conduced more glacier melting water. This part of water supply, together with the increasing precipitation and the descending evaporation, contributed to the enlargement of Nam Co Lake. The roughly water balance analyses of lake water volume implied that, in two study periods (1971-1991 and 1992-2004), the precipitation supplies (direct precipitations on the lake area and stream flow derived from precipitations) accounted for 63% and 61.92% of the whole supplies, while the glacier melting water supplies occupied only 8.55% and 11.48%, respectively. This showed that precipitations were main water supplies of the Nam Co Lake. However, for the reason of lake water increasing, the increased amount from precipitations accounted for 46.67% of total increased water supplies, while the increased amount from glacier melting water reached 52.86% of total increased water supplies. The ratio of lake evaporation and lake volume augment showed

关键词：西藏的高原 Nam 公司湖湖区域变化遥感水平衡

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Composition, spatial distribution, and environmental significance of water ions in Pumayum Co catchment, southern Tibet

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Journal of Geographical Sciences 2010年第1期20卷 109-120页

作者： ZHU Liping JU Jianting WANG Yong xie manping WANG Junbo PENG Ping ZHEN Xiaolin LIN Xiao Institute of Tibetan Plateau Research CAS Beijing 100085 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The chemistry of major cations （Mg^2＋, Ca^2＋, Na^＋, and K^＋） and anions （HCO3^-, SO4^2-, and CI^-） in the water of Lake Pumayum Co and its inflow river was studied, revealing the obvious ionic difference among various inflow rivers and the lake. The chemical type of the lake water was Mg^2＋-Ca^2＋-HCO3^- -SO^2＋, but the major ions of the main inflow rivers were Ca^2＋-Mg^2＋-HCO3^-. In the lake inlet of Jiaqu River, the main inflow river, there was significant variance of water chemistry within the depth less than 2 m. However, it was almost homogeneous at other area of the lake. Therefore, with the evidence of distribution of water chemistry and oxygen isotope of lake water, a conclusion can be outlined that Jiaqu River had a distinct effect on the hydrochemistry of the water on the submerged delta, whereas this is not the case for other rivers. The Gibbs plot revealed that the dominant mechanism responsible for controlling chemical compositions of the lake water was rocks weathering in the drainage area. Ion ratios and ternary plots further explored the main processes controlling the water chemistry of the catchment, i.e., carbonate weathering, pyrite weathering, and silicate weathering. The different hydrochemistry characteristics between river water and lake water may result from the CaCO3 precipitation. The findings will benefit the explanation of the environmental significance of carbonate in paleolimnological studies in the lake.

关键词： Lake Pumayum Co hydrochemistry spatial distribution sedimentary process carbonate

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A TAXONOMICAL AND ECOLOGICAL OVERVIEW OF RECENT AND HOLOCENE OSTRACODES OF THE NAM CO REGION, SOUTHERN TIBET

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第四纪研究 2009年第4期29卷 665-677页

作者： C. Wrozyna P. Frenzel manping xie Liping Zhu A. Schwalb Institut far Umweltgeologie Technische Universit~it Braunschweig PockelsstraBe 3 38106 Braunschweig Germany Institut fur Geowissenschaften Friedrich-Schiller-Universitat Burgweg 11 07749 Jena Germany Institute of Tibetan Plateau Research Chinese Academy of Sciences BeijingChina

We present a list of living and (sub) fossil Ostracoda (Crustacea) from Holocene sediments from Lake NamCo,Southern Tibet, including descriptions, distribution and ecological data of the important taxa from the Nam Cocatchment. Species associations from lake surface sediments, sediment cores and outcrop samples consist of eight speciesincluding Candona candida ( O.F. Müller, 1776 ) , Candona xizangensis ( Huang, 1982 ) , Eucypris afghanistanensis( Hartmann, 1964) , Fabaeformiscandona danielopoli ( Yin & Martens, 1997 ) , Ilyocypris cf. mongolica ( Martens, 1991 ) ,? Leucocythere dorsotuberosa ( Huang, 1982 ) , Leucocytherella sinensis ( Huang, 1982 ) and Limnocythere inopinata ( Baird,1843). The dominant species are ? L. dorsotuberosa and L. sinensis. They show morphological variations with different degreesof ornamentation. We regard the variable noding and rib formation as intraspecific variability possibly driven byenvironmental factors. In general,the number and degree of ribs increases with water depth in ? L. dorsotuberosa. Thus,theornamentation may present a means to reconstruct(paleo) water depths. Our list is intended to serve as a taxonomical andpaleoecological primer for future paleolimnological work.

关键词：化石甲壳类西藏沉积物

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Environmental changes reflected by n-alkanes of lake core in Nam Co on the Tibetan Plateau since 8.4 kaB.P.

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Chinese Science Bulletin 2008年第19期53卷 3051-3057页

作者： LIN Xiao ZHU LiPing WANG Yong WANG JunBo xie manping JU JianTing Roland MAUSBACHER Antje SCHWALB Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institut for Geographie Friedrich-Schiller-Universitat D-07743 Jena Germany Institut für Umweltgeologie Technische Universitat 38106 Braunschweig Germany

The n-alkanes are extracted from NMLC-1 core that was drilled in the Nam Co, central Tibet. They are measured by using Gas Chromatography and Mass Spectrometry (GC/MS) for componential and quantitative analyses. According to the constructed depth-age model, the component and concentration of n-alkanes, together with total organic carbon (TOC), total nitrogen (TN) and carbonate are used to elu- cidate palaeoenvironmental changes of Nam Co during the past 8.4 ka. The results indicate that Holo- cene environment performs three stages in the lake area. In the stage of 8.4―6.7 kaB.P., it was warmer while precipitation slightly increased. This stage was ended by an obvious cold/dry event. During 6.7― 5.8 kaB.P., temperature increased rapidly and reached its maximum values at about 6.0 kaB.P. The environments were warm/wet optimum for the blooming of terrestrial plants and submerged aquatic plants. After that, temperature decreased continuously and showed the lowest values at about 3.0 kaB.P. From 2.9 kaB.P. to the present, temperature rose again but alternated with cold and warm. The lake area tended to be dry after 1.4 kaB.P. During 600―400 aB.P., the environmental feature was the reflection of "Little Ice Age".

关键词：湖泊沉淀物环境变化链烷烃西藏

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Hydrodynamic process of Tibetan Plateau lake revealed by grain size:Case study of Pumayum Co

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Chinese Science Bulletin 2012年第19期57卷 2433-2441页

作者： JU JianTing ZHU LiPing FENG JinLiang WANG JunBo WANG Yong xie manping PENG Ping ZHEN XiaoLin LÜXinMiao Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Tourism and Geography Sciences Yunan Normal UniversityKunming 650500China

Under the background of global warming,some lakes on the Tibetan Plateau(TP) are potentially sensitive to temperature *** a case study of Pumayum Co,where glacier meltwater is important to supply(we call this a glacier-fed lake hereafter),we analyze the sensitivity of lake sediment grain size to temperature *** is done by resolving the modern hydrodynamic process,coupled with comparison of paleoclimatic *** to the spatial distributions of parameters,percentage of grain size and the grain size frequency distribution curve,hydrodynamic processes are *** clastic sedimentation types are thereby *** the open lake area,suspended load transport is the main transport *** Size Trend Analysis(GSTA),a sediment dynamics model,reveals a trend toward eastward *** indicates that the largest and glacier-fed river,the Jiaqu River,influences the entire lake(not just the subsurface alluvial fan),and that lake sediment grain size may serve as a temperature *** series comparison between grain size of a short core from the central lake and meteorological data confirms this temperature indication,which in turn shows reliability of the method discriminating the hydrodynamic *** case study will improve the ability of paleoclimatic reconstruction using lake sediment in glacier-fed lakes on the Tibetan Plateau.

关键词：高原湖泊青藏高原晶粒尺寸水动力过程案例显示沉积物粒度动力学过程

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Twinning aspects and their efficient roles in wrought Mg alloys: A comprehensive review

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JOURNAL OF MAGNESIUM AND ALLOYS 2024年第6期12卷 2201-2230页

作者： Shah, S. S. A. Liu, manping Khan, Azim Ahmad, Farooq Abdullah, M. R. Zhang, Xingquan Xu, Shiwei Peng, Zhen Jiangsu Univ Sch Mat Sci & Engn Zhenjiang 212013 Peoples R China Anhui Univ Technol Sch Mech Engn Maanshan 243002 Peoples R China Hunan Univ Coll Mech & Vehicle Engn Changsha 410082 Peoples R China

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium (Mg) alloys. Specifically, twins play a crucial role in initiating dynamic recrystallization (DRX), while twin regions experience rapid recrystallization during static recrystallization (SRX). The activation of twinning can lead to changes in lattice orientation, significantly impacting the final texture in Mg alloys. The active roles of twinning are influenced by various factors during the activation process, and the mobility of twin boundaries (TB) can be amplified by stress effects, dislocation interactions, and thermal effects. Conversely, annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them, restraining their motion. Events such as segregation may also alter the twinning propensity in Magnesium-rare earth (Mg-RE) alloys. While {10-111 contraction twins (CT) and {10-111-{10-121 double twins (DT) can promote dynamic recrystallization (DRX), they also pose a risk as potential sources of voids and cracks. Additionally, understanding the nucleation and growth mechanisms of twinning is crucial, and these aspects are briefly reviewed in this article. Considering the factors mentioned above, this article summarizes the recent research progress in this field, shedding light on advancements in recent eras. (c) 2024 Chongqing University. Publishing services provided by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license ( http://***/licenses/by-nc-nd/4.0/ ) Peer review under responsibility of Chongqing University

关键词： Mg alloys Twinning Recrystallization Texture Mechanical properties AZ31 MAGNESIUM ALLOY 0 (1)OVER-BAR 2 ROLLED MG-3AL-1ZN ALLOY GD-Y ALLOY STATIC RECRYSTALLIZATION BEHAVIOR ENHANCED STRETCH FORMABILITY COMPRESSION YIELD ASYMMETRY GREATER-THAN DISLOCATION GRAIN-BOUNDARY MOTION MECHANICAL-PROPERTIES

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On the Unusual Holocene Carbonate Sediment in Lake Nam Co,Central Tibet

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Journal of Mountain Science 2009年第4期6卷 346-353页

作者： LI Minghui KANG Shichang ZHU Liping WANG Feiyue WANG Junbo YI Chaolu FANG Xiaomin xie manping Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research CAS Beijing 100085 China State Key Laboratory of Cryospheric Science CAS Lanzhou 730000 China Department of Environment and Geography and Department of Chemistry University of Manitoba Winnipeg MB R3T 2N2 Canada

In lacustrine sediments,aragonite is a widespread mineral,whereas monohydrocalcite is a rare carbonate mineral. In the cold and high-attitude Xizang (Tibetan) Plateau,where aragonite has been commonly found in lacustrine sediments,there is no aragonite,but low-Mg calcite,monohydrocalcite and trace dolomite. The lake receives solutes primarily from surface runoffs and remains fairly constant water chemistry for a long time. The total CaCO3 percentage in sediments could be controlled by evaporation and inflow of detrital materials. The absence of aragonite is unusual when compared to other lacustrine sediments from the Tibetan Plateau. This could be due to low Ca/Mg ratio,low salinity,low Mg and Ca concentration. Monohydrocalcite might precipitate from the lake water mediated by biological activities. Low-Mg calcite originated from minor ostracoda shell and the precipitation of lake water with biological activities.

关键词：湖泊沉积物碳酸盐矿物西藏中部纳木错全新世盐湖西藏高原地表径流

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西藏色林错沉积物介壳同位素重建的2000年以来气候变化研究

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第四纪研究 2023年第1期43卷 83-94页

作者：郭姝雯余芳艳王哲何志兴尚发美谢曼平云南师范大学地理学部云南省高原地理过程与环境变化重点实验室云南昆明650500 中国电建集团昆明勘测设计研究院有限公司云南昆明650000 云南省澄江县第一中学云南澄江652599

青藏高原作为印度季风与西风交汇的特殊区域,对全球气候变化响应敏感,成为了古气候研究的热点地区。青藏高原湖泊众多,存在巨厚连续的湖泊沉积物,为古气候重建提供了优良载体。而介形类壳体在湖泊中沉积连续,生长过程记录了气候变化,同... 详细信息

青藏高原作为印度季风与西风交汇的特殊区域,对全球气候变化响应敏感,成为了古气候研究的热点地区。青藏高原湖泊众多,存在巨厚连续的湖泊沉积物,为古气候重建提供了优良载体。而介形类壳体在湖泊中沉积连续,生长过程记录了气候变化,同时有效屏蔽了湖泊水体中同位素的累积效应,能够反映介壳生长阶段短时间尺度的同位素水平,理论上是高精度气候重建的理想载体。基于此,本研究选取青藏高原中部地区湖泊色林错湖芯(SL16-1-1)顶部0~107cm部分为对象,对其中的介形类壳体进行种属鉴定及碳氧同位素分析,以期建立高分辨率的古环境变化记录,结合沉积物Rb/Sr、Ti/Si环境代用指标,重建色林错湖区近2000年来的气候变化记录,结果揭示了:1)介形类壳体碳氧稳定同位素变化对气候变化(尤其冷气候)尤为敏感,是重建高分辨率环境变化过程的优良载体;2)色林错地区对小冰期冷事件的响应较早于其他地区;3)色林错介形类壳体2000年来的气候重建结果与青藏高原研究成果大体一致,特别是与内地文献记录和物候史料记载高度一致,说明色林错湖泊记录具有广泛代表性,同时证实利用湖泊沉积物介形类壳体进行古气候高分辨率重建具有可靠性。

关键词：介形类青藏高原湖泊沉积物 2000年气候变化

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云南纳帕海17Ka的植硅体记录以及环境意义

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当代化工研究 2023年第7期 75-78页

作者：何志兴郭姝雯吴璇谢曼平云南师范大学地理学部云南650500

地处中国滇西北横断山脉中段的纳帕海受印度季风和高原季风的共同影响,气候复杂多变,利于研究南亚季风和东亚季风的耦合关系。本文从植硅体角度对香格里拉纳帕海湖芯钻孔(ZD981)0~6.35m部分进行古气候研究,得到了一系列环境气候信息,结... 详细信息

地处中国滇西北横断山脉中段的纳帕海受印度季风和高原季风的共同影响,气候复杂多变,利于研究南亚季风和东亚季风的耦合关系。本文从植硅体角度对香格里拉纳帕海湖芯钻孔(ZD981)0~6.35m部分进行古气候研究,得到了一系列环境气候信息,结合已有的AMS14C测年数据,重建纳帕海近17Ka的古气候演化过程,并探讨其变化规律以及影响因素。分析结果表明,由于局部环流和地形作用的影响,纳帕海植硅体记录所反映的气候特征与其他地区所重建气候存在明显差异性,17800年以来纳帕海的气候变化主要经过了温凉偏干—温暖—湿热—温—湿热—温凉偏干的6个阶段。该结果丰富了我国西南地区古气候变化、古环境变迁的相关研究。

关键词：植硅体纳帕海气候变迁季风作用古环境

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卡维地洛联合生长抑素治疗肝硬化食管胃底静脉曲张破裂出血患者的效果

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中国民康医学 2024年第4期36卷 42-44页

作者：黄曼萍商丘市第三人民医院感染科河南商丘476000

目的:观察卡维地洛联合生长抑素治疗肝硬化食管胃底静脉曲张破裂出血患者的效果。方法:回顾性分析2019年1月至2023年2月该院收治的75例肝硬化食管胃底静脉曲张破裂出血患者的临床资料,按照治疗方法不同将其分为对照组(n=37)和观察组(n=... 详细信息

目的:观察卡维地洛联合生长抑素治疗肝硬化食管胃底静脉曲张破裂出血患者的效果。方法:回顾性分析2019年1月至2023年2月该院收治的75例肝硬化食管胃底静脉曲张破裂出血患者的临床资料,按照治疗方法不同将其分为对照组(n=37)和观察组(n=38)。两组均予以常规治疗,在此基础上,对照组予以生长抑素治疗,观察组在对照组基础上联合卡维地洛治疗。比较两组临床指标(止血时间、住院时间和输血量)水平、治疗前后门静脉指标(门静脉压、门静脉血流速度、门静脉血流量)水平、不良反应发生率和再出血发生率。结果:观察组止血时间、住院时间均短于对照组,输血量少于对照组,差异有统计学意义(P0.05);观察组再出血发生率为7.89%(3/38),低于对照组的27.03%(10/37),差异有统计学意义(P<0.05)。结论:卡维地洛联合生长抑素治疗肝硬化食管胃底静脉曲张破裂出血患者可改善临床指标水平,降低门静脉指标水平和再出血发生率,效果优于单纯生长抑素治疗。

关键词：生长抑素卡维地洛肝硬化食管胃底静脉曲张破裂出血门静脉不良反应再出血

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