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Science china Earth sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2. XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, institute of Atmospheric Physics, chinese Academy of {2., beijing 10002., china 2. Graduate School of the chinese Academy of {2., beijing 100039, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate School of the chinese Academy of sciences Beijing China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2. XIONG Shangfa3 & HUANG Fengbao1 1. Nanjing institute of geology and Paleontology,{2. Academy of sciences,Nanjing 2.0008,china 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. institute of geology and Geophysics,{2. Academy of sciences,beijing 10002.,china Nanjing institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 872. a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 872. to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Palynological characters of Glycyrrhiza,Glycyrrhizopsis,and Meristotropis(Leguminosae),with special reference to their taxonomic significance

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Journal of Systematics and Evolution 2010年第6期48卷 455-463页

作者： 1,2.ei MENG 2.iang-Yun ZHU 1(College of Biological sciences,china Agricultural University,{2. 100094,china) 2.institute of Botany,chinese Academy of sciences,{2. 100093,china) (College of Biological sciences China Agricultural University Beijing 100094 China) (institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The pollen morphology of 11 species of the genus Glycyrrhiza *** one from each of the genera Glycyrrhizopsis Boiss.& *** Meristotropis Fisch.& *** investigated by scanning electron *** pollen morphology,the main differences between Glycyrrhizopsis and Glycyrrhiza are:Glycyrrhizopsis-pollen grains 36.63 × 40.42.μm in size,oblate spheroidal in shape;and Glycyrrhiza-pollen grains 2..47-33.18 × 2..82.31.83 μm in size,prolate spheroidal in *** and Glycyrrhiza should be recognized as two distinct genera based on palynological and morphological *** and Glycyrrhiza are similar in many important palynological and morphological characters,suggesting that the two should be *** Glycyrrhiza,two types of pollen grains,3-lobed-circular or subtriangular in polar view,are found in different species,in accordance with morphological differences in the two groups,shedding light on the classification and evolution of the genus.

关键词： exine sculpture morphological character pollen morphology taxonomic revision.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, chinese Academy of {2., beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the chinese Academy of {2., beijing 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the chinese Academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Seasonal variation of global stratosphere-troposphere mass exchange

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Progress in Natural Science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2. Lu Daren2.and Sun Zhaobo1(1. institute of Atmospheric sciences, Nanjing University of Information Science and Technology, Nanjing 2.0044,{2. 2. LAGEO, institute of Atmospheric Physics, chinese Academy of sciences, beijing 10002.,{2.) institute of Atmospheric sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2.01 using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.

Boundedness of solutions and existence of invariant tori for generalized pendulum type equation

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chinese Science Bulletin 1997年第20期42卷 1673-1675页

作者： HUANG Hai and YUAN Rong1. institute of Mathematics, chinese Academy of {2., beijing 100080, china 2. Department of Mathematics, beijing Normal University, beijing 100875, china institute of Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Beijing Normal University Beijing China

MOTIVATED by various significant applications to non-Newtonian fluid theory, diffusion offlows in porous media, nonlinear elasticity, and theory of capillary surfaces, several authors(see refs.[1,2. and references cited therein ) have recently studied the existence of periodicsolutions and other properties for the following differential equation:

关键词： boundeduess of solutions invariant tori quasiperlodic solutions Moser’s small twist theorem.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. institute of Tibetan Plateau Research, chinese Academy of {2., beijing 100085, china 2. Faculty of Earth {2. and Mineral Resources, china University of Geo{2., beijing 100083, china 3. Tianjin institute of geology and Mineral Resources, Tianjin 300170, china institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Faculty of Earth sciences and Mineral Resources China University of Geosciences Beijing China Tianjin institute of geology and Mineral Resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

Jinning granodiorite and diorite deeply concealed in the central Tarim Basin

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Science china Earth sciences 2005年第12期48卷 2061-2068页

作者： LI Yuejun1, 2. SONG Wenjie2. WU Genyao1, WANG Yifen1, LI Yuping2.& ZHENG Duoming2.1. institute of geology & Geophysics, {2. Academy of sciences, beijing 10002., china 2. Tarim Oil-field Company, Petrochina, Korla 841000, china institute of geology & Geophysics Chinese Academy of Sciences Beijing China Tarim Oil-field Company PetroChina China

The 72.0-m-deep Well Tacan 1 in the central Tarim Basin is the deepest in china. Purplish gray medium-grained granodiorite containing dark gray fine-grained diorite xenolith is revealed at the base of the well (7169―72.0 m), and they are results of the Jinning magmatic activities. Trace-element geochemistry and REE profiles of both rock types are similar, indicating that they are calc-alkaline series I-type granitoid. Proxies of diorite signify the development of a magmatic arc due to subduction at ca. 12.0 Ma. The granodiorite was formed before 890―932.Ma. However, more study is needed to clarify if the arc diorite represents a ca. 300 Ma extension of the subduction or a reactivation during the orogenic collision event at ca. 900 Ma.

关键词： diorite, granodiorite, magmatic arc, Jinning orogeny, Tarim Basin.

Global convergence property of s-dependent GFR conjugate gradient method

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chinese Science Bulletin 1998年第23期43卷 1959-1965页

作者： WANG Changyu 1,2.and ZHANG Yuzhong\+1 1. institute of Operations Research in Qufu Normal University, Qufu 2.3165, china 2. institute of Applied Mathematics, chinese Academy of sciences, beijing 100080, china institute of Operations Research Qufu Normal University Qufu China institute of Applied Mathematics Chinese Academy of Sciences Beijing China

An \%S\%_dependent GFR method and a generalized conjugate gradient method are designed. Two estimated values of upper bounds for the ratio of β k to β FR k are given. The two convergence theorems are proved. The global convergent properties of \%s\%_dependent GFR method are obtained adopting several choice strategies of steplength and some results in recent literature are extended.

关键词： steplength linear search global convergence conjugate gradient.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South china Sea institute of Oceanology, {2. Academy of sciences. Guangzhou 510301, china 2. State Key Laboratory of Loess and Quaternary geology, Earth Environmental institute, {2. Academy of sciences, Xi’an 710075, china 3. institute of geology and Geophysics, {2. Academy of sciences, beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.