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Groundw.ter recharge and climatic change during the last 1000 years from unsaturated zone of SE Badain Jaran Desert

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Chinese Science Bulletin 2003年第14期48卷 1469-1474页

作者： MAJinzhu LIDina ZHANGJiaw. w.M.edmunds C.Prudhomme CenterforAridEnvironmentandPaleoclimateResearch NationalLaboratoryofWesternChina'sEnvironmentalSystemCollegeofEarthandEnvironmentSciencesLanzhouUniversityLanzhou730000.China BritishGeologicalSurvey WallingfordOxfordshireUKorrespondenceshouldbeaddressedtoMaJinzhu

The history of groundw.ter recharge and climatic changes during the last 1000 years has been estimated and reconstructed using environmental chloride from unsaturated zone profile in the southeast Badain Jaran Desert, Nw.China. By using a steady-state model for duplicate unsaturated zone chloride profiles, the long-term recharge at the site w.s estimated to be 1.3 mm yr-1. From one profile, w.ich reached the w.ter table, the climatic change events of 10—20 years duration w.re w.ll preserved. There w.re 3 w.t phases and 4 dry episodes during the recent 800 years according to the peaks and troughs of recharge rate calculated via chloride concentration and moisture content. There w.s a dry episode before 1290 AD. At ca. 1500—1530 AD, w.ich is an important date, there w.s an abrupt change from drought to w.t conditions. At the beginning of the 1800s, local climate changed from w.t to dry occurred and subsequently deteriorated over the past 200 years. The unsaturated profile w.s compared w.th the Guliya ice core records. The agreement of w.t and dry phases from 1200 to 1900 AD is quite good, w.ilst trends diverged during the last 100 years. It seems that the large-scale climate difference took place betw.en mountain regions and the desert basin in Nw.China during the 20th century, w.ich closely correspond to the w.ter table reduction of some 1 metre.

关键词：地下水回灌补注气候变化不饱和带中国西北地区沙漠氯化物

On Self-Adjointness of the Product of Tw. Second-Order Differential Operators

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Acta Mathematica Sinica,English Series 1999年第3期15卷 375-383,385-386页

作者： D. E. edmunds Department of Mathematics Inner Mongolia University Huhhot 010021 P. R. China Centre for Mathematical Analysis and its Applications University of Sussex Palmer Brighton BN1 9QH England

In this paper, the problem of self-adjointness of the product of tw. differential operators is considered. A number of results concerning self-adjointness of the product L2L1 of tw. second-order self-adjoint differential operators are obtained by using the general construction theory of self-adjoint extensions of ordinary differential operators.

关键词： Self-adjoint operator Differential operator Product of tw. differential operators

Soil profile evolution follow.ng land-use change:implications for groundw.ter quantity and quality

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Soil profile evolution following land-use change:implication...

On a Measure of Non-compactness for Some Classical Operators

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Tianming Huang Zhonghe Pang w.mike edmunds Key Laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences Oxford University Centre for w.ter Research School of Geography and the Environment Oxford University

Soil and vadose zone profiles are used as an archive of changes in groundw.ter recharge and w.ter quality follow.ng changes in land use in an area of the Loess Plateau of China.A typical rain-fed loess-terrace agriculture region in Hequan,Guyuan,is taken as an example,and multiple tracers(chloride mass balance,stable isotopes,tritium and w.ter chemistry) are used to examine groundw.ter recharge mechanisms and to evaluate soil w.ter chloride as an archive for recharge rate and w.ter *** show.that groundw.ter recharge beneath natural uncultivated grassland,used as a baseline,is about 94-100 mm year and that the time it takes for annual precipitation to reach w.ter table through the thick unsaturated zone is from decades to hundreds of years(tritium free).This recharge rate is 2-3 orders of magnitude more than in the other semiarid areas w.th similar annual rainfall but w.th deep-rooted vegetation and relatively high *** of the w.ter that eventually becomes recharge originally infiltrated in the summer *** conversion from native grassland to w.nter w.eat has reduced gioundw.ter recharge by 42-50%(50-55 mm year for recharge),and the conversion from w.nter w.eat to alfalfa resulted in a significant chloride accumulation in the upper soil zone,w.ich terminated deep *** paper also evaluates the time lag betw.en potential recharge and actual recharge to aquifer and betw.en increase in solute concentration in soil moisture and mat in the aquifer follow.ng land-use change due to the deep unsaturated ***(?) 2012 John w.ley & Sons,Ltd.

关键词： groundw.ter recharge land-use change chloride mass balance Loess Plateau of China soil profile

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1847-1862页

作者： David E.edmunds Alberto FIORENZA Alexander MESKHI School of Mathematics Cardiff University Dipartimentodi Costruzioni e Metodi Matematici in Architettura Scuola Normale Superiore

The measure of non-compactness is estimated from below.for various operators, including the Hardy-Littlew.od maximal operator, the fractional maximal operator and the Hilbert transform, all acting betw.en w.ighted Lebesgue spaces. The identity operator acting betw.en w.ighted Lebesgue spaces and also betw.en the counterparts of these spaces w.th variable exponents is similarly analysed. These results enable the lack of compactness of such operators to be quantified.

关键词： measure of non-compactness maximal functions singular integrals embeddings w.ight

干旱区地下水补给与气候变化的包气带地球化学记录--以巴丹吉林沙漠为例

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地球学报 2003年第Z1期24卷 190-195页

作者：马金珠李丁陈发虎 w. M. edmunds 兰州大学甘肃兰州730000 British Geological Survey Wallingford OX10 8BBUK

氯平衡原理在降雨极其稀少的干旱区研究地下水补给具有较强的适用性,与H、O稳定同位素及含水量在包气带垂向的变化相结合,能够准确地计算地下水的多年平均补给率.在巴丹吉林沙漠南缘的2个钻孔剖面分别记录了过去574 a(B1)和812 a(B2)以... 详细信息

氯平衡原理在降雨极其稀少的干旱区研究地下水补给具有较强的适用性,与H、O稳定同位素及含水量在包气带垂向的变化相结合,能够准确地计算地下水的多年平均补给率.在巴丹吉林沙漠南缘的2个钻孔剖面分别记录了过去574 a(B1)和812 a(B2)以来的补给量变化过程及其所反映的气候波动特征,在该地区,多年降雨量为89 mm,而补给量平均仅为1.3 mm/a,从B2剖面完整的记录可以将800 a B P气候划分为4个干期和3 个湿期.1500～1530年是干旱区气候突变的时期,18世纪末至19世纪初是气候环境演化的又一个十分重要的时间界限,自此以后的漫长时间,干旱化进程进一步加剧.

关键词：地下水补给气候变化包气带氯平衡原理

Rene FRIEDMAN and Barbara ADAMS, ed. The Follow.rs ofHorus. Studies Dedicated to Michael Allen Hoffman. EgyptianStudies Association Publication No. 2 = Oxbow.Monograph ***: Oxbow.Books, 1992. ISBN 0 946897 44 1. Pp. [xxⅷ] +356, many llus. No pr

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Journal of Ancient Civilizations 1995年 10卷 149-154页

作者： edmunds.Meltzer IHAC.NortheastNormalUniversiy Changchun PRC

Michael Hoffman did a great deal to transform, perhaps even revolutionize, much of the archaeological enterprise in Egypt, most especially the archaeological study of Egyptian prehistory and the emergence of historic Egypt, before his untimely death. The goals, methods, priorities and perspectives of archaeologists as w.ll as historians have been catalyzed by his fieldw.rk, publications, and w.de presentation of his results. It is not too much to say that the consciousness of many of us has been raised, our agenda has changed, as a result of his "New.w.rld-style" anthropologically and environmentally grounded

关键词： enterprise ISBN VIEw

AN OBSERVATION ON NOMINAL SENTENCES w.TH N-DEMONSTRATIVES IN CLASSICAL EGYPTIAN

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Journal of Ancient Civilizations 1995年 10卷 83-100页

作者： edmunds.Meltzer IHACNortheastNormalUniversity PRC

The employment of both "bipartite" and "tripartite" nominal sentence patterns containing demonstratives of the n-series in Middle Egyptian^1 show. a characteristic sufficiently consistent to w.rrant the suggestion that a semantic constraint is operative: VIZ., that those sentences are employed w.th NPs that are [-PERSON], not [+PERSON]. Therefore, sentences such as ~*R’/it.i/ink (pw. nn/nf(3)/n3/nw.are excluded. In a sentence suc(?) as bit.i pw.n3 "This is my character/conduct"~2, bit.i "my character/conduct" is [-PERSON], w.ereas one could not say, e.g., ~*s3. i pw.n3 "This is my son." According to this hypothesis, all Middle

关键词：玉竹比久刀工比内山凹

巴丹吉林沙漠包气带Cl^-示踪与气候记录研究

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中国沙漠 2004年第6期24卷 674-679页

作者：马金珠李丁李相虎 edmunds w.M 兰州大学西部环境教育部重点实验室中德干旱研究中心甘肃兰州730000 British Geological Survey Wallingford Oxfordshire UK

Cl-是自然界中最稳定的示踪剂,包气带水Cl-浓度与降水中Cl-浓度的差异可以反映降水的有效入渗补给量和包气带水的年龄。基于CMB的氯累积年龄可以用36Cl/Cl在三个时间尺度上校正。利用CMB研究了巴丹吉林沙漠南缘的两个钻孔剖面的Cl-与含... 详细信息

Cl-是自然界中最稳定的示踪剂,包气带水Cl-浓度与降水中Cl-浓度的差异可以反映降水的有效入渗补给量和包气带水的年龄。基于CMB的氯累积年龄可以用36Cl/Cl在三个时间尺度上校正。利用CMB研究了巴丹吉林沙漠南缘的两个钻孔剖面的Cl-与含水量的分布状况,计算了800a以来的地下水补给量及其所反映的气候波动特征。在该地区,多年平均降雨量为89mm,而平均补给量仅为1 3mm。干旱沙漠地区最近800a气候明显经历了4个干期和3个湿期。1500—1530年是干旱区气候突变的时期,18世纪末至19世纪初是气候环境演化的又一个十分重要的时间界限,自此以后的漫长时间,干旱化进程进一步加剧。

关键词：气候记录补给量示踪巴丹吉林沙漠包气带平均降雨量气候突变入渗干旱 Cl^-

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石羊河流域水化学演化与地下水补给特征

资源科学 2005年第3期27卷 117-122页

作者：马金珠李相虎黄天明 w.M.edmunds 兰州大学西部环境教育部重点实验室兰州730000 Oxford Centre for w.ter Research Oxford University OxfordOX1 3TB

以地球化学和包气带氯质量平衡技术相结合,通过腾格里沙漠包气带沙芯记录和石羊河流域地下水、地表水地球化学的研究,探讨中国西北干旱区地下水补给历史及其气候特征和地下水地球化学演化规律。石羊河流域水化学在天然状态下具有水平分... 详细信息

以地球化学和包气带氯质量平衡技术相结合,通过腾格里沙漠包气带沙芯记录和石羊河流域地下水、地表水地球化学的研究,探讨中国西北干旱区地下水补给历史及其气候特征和地下水地球化学演化规律。石羊河流域水化学在天然状态下具有水平分带性,上游地表水矿化度小于360mg l,下游达1000mg l;武威盆地洪积扇地下水主要为HCO3-SO4型水,至民勤终端湖演变为Cl-SO4型水,矿化度相应由500mg l增加为17g l左右。在腾格里沙漠的一个钻孔剖面记录了过去930年以来的补给量变化过程及其所反映的气候波动特征,氯质量平衡法计算的地区补给量平均仅为1 26mm,从剖面完整的记录可以将930aBP气候划分为4个干期和3个湿期。

关键词：石羊河流域水化学演化补给特征腾格里沙漠水地球化学地下水补给西北干旱区质量平衡法平衡技术演化规律天然状态水矿化度武威盆地波动特征变化过程剖面记录包气带补给量特征和气候分带性洪积扇地表