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A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science china earth {2. 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

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china earth {2. 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3, QU Wenjun1 & CHEN Jiangfeng2.1. National Research Center of Geoanalysis, Beijing 100037, china 2. Laboratory for earth Material Cycling, School of earth and Space sciences, University of Science and Technology of china, Hefei 2.002., china 3. institute of Mineral Resource, chinese Academy of Geological sciences, Beijing 100037, china National Research Center of Geoanalysis University of Science and Technology of china chinese Academy of Geological sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 833 ± 35 Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 130 ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3). The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china earth {2. 2008年第5期51卷 654-664页

作者： HU Guang1,2. JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, institute of earth {2., chinese Academy of sciences, xi’an 710075, china 2.Graduate University of the chinese Academy of sciences, Beijing 100049, china 3 College of Resources and {2.al Science, Nanjing Agricultural University, Nanjing 2.0095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of the chinese Academy of sciences Beijing China College of Resources and environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2. the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Estimation on dynamic release of phosphorus from wind-induced suspended particulate matter in Lake Taihu

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Science china earth {2. 2004年第8期47卷 710-719页

作者： FAN Chengxin1, ZHANG Lu1,2. QIN Boqiang1, WANG Sumin1, HU Weiping1 & ZHANG Chen1 1. Taihu Lake Laboratory for Ecosystem Research, Nanjing institute of Geography & Limnology, chinese Academy of {2., Nanjing 2.0008, china 2. Graduate School of chinese Academy of {2., Beijing 100039, china Taihu Lake Lab. for Ecosystem Res. Nanjing Inst. of Geography/Limnology Chinese Academy of Sciences Nanjing 210008 China Grad. Sch. of chinese Acad. of Sci. Beijing 100039 China

Through man-made disturbance experiments, the corresponding relationships be-tween suspended particulate matter (SPM) and wind speed in different lake areas were simu-lated, the physicochemical formal transformation and biological mineralizing and decaying processes of phosphorus in SPM were studied, the contribution of phosphorus transformation to phosphorus loading of the water of Lake Taihu was quantitatively estimated. The results show that about 0.44 t·a-1 loading in Lake Taihu mainly comes from phosphorus-releasing action of SPM in physicochemical transformed to soluble reactive phosphorus (SRP), and the contribution mainly from biological mineralizing and decaying was about 42..8 t·a-1, which is equal to 15.0% of the total external loading of Lake Taihu, namely 4.7—7.5 times as much as SRP loading en-tering the lake by the rivers; thus it is the important source in dynamical internal loading of the lake. The determining factors for dynamical internal loading in lakes are organic phosphorus content in suspended solid and its biological transition availability.

关键词： phosphorus release,wind wave disturbance,particulate decaying,dynamical loading,Lake Taihu.

Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas

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Science china earth {2. 2005年第7期48卷 849-862页

作者： ZHENG Yadong 1 & WANG Tao2.1. Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University), Ministry of Education, Beijing 100871, china 2. institute of Geology, {2. Academy of Geological sciences, Beijing 100037, china Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University) Ministry of Education Beijing 100871 China institute of Geology Chinese Academy of Geological Sciences Beijinq 100037 China

The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.10 and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 165°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ～66°, while the later average kinematic vorticity was ～0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.

关键词： Mesozoic thrusting,late-orogenic collapse,kinematic vorticity number,stress state.

Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2.)Shui-Cai WANG~2.Jun-Fang HE~2.Hui CHEN~3 1 institute of Photonics and Photo-Technology,Northwest University,xi'an 710069,china 2.State Key Laboratory of Transient Optics and Photonics,xi 'an institute of Optics and Precision Mechanics,chinese Academy of sciences,xi'an 710068.china 3 Laboratoty of Photosynthesis Basic Research,institute of Botany,chinese Academy of sciences,Beijing 100093,china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb62.,Chlb646,Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 62. nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were determined to be 1.44ns,1.43 ns,636 ps and 713 ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern china

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Science china earth {2. 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions environmental and Engineering Research institute, {2. Academy of sciences, Lanzhou 730000, china 2. College of Geography, Nanjing Normal University, Nanjing 2.0097, china Cold and Arid Regions environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China College of Geography Nanjing Normal University Nanjing China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern china. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

Study of thin cloud removal method for CBERS-02.image

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Science china(Technological sciences) 2005年第S2期48卷 91-99页

作者： MA Jianwen1, GU xingfa1, FENG Chun2.& GUO Jianning2.1. institute of Remote Sensing Application, chinese Academy of {2., Beijing 100101, china 2. china Center for Resource Satellite Data and Applications, Beijing 100073, china institute of Remote Sensing Application Chinese Academy of Sciences Beijing 100101 China china Center for Resource Satellite Data and Applications Beijing 100073 China

The china Brazil earth Resources Satellite (CBERS) ended the dependence on foreign satellites. Along with the series of CBERS and the enhancement of satellite applications, it is necessary to search correlative data processing methods. Because cloud appears in the atmosphere, an image with clear sky conditions is often hard to obtain. How to remove cloud is an important sector of increasing image quality. An improved homomorphism filtering method is adopted to remove thin cloud qualitatively at first, and all bands are selected to classify pixels. Based on the fact that visible band images contain more aerosol effects than infrared bands, visible bands are used to determine clear or hazy regions and the reflectances of different surface classes in clear regions are calculated. At last the mean reflectance of the same classes in clear and hazy regions is matched to remove cloud. The image visual effect is improved; meanwhile, the ground reflectance is retrieved to meet the needs of remote sensing quantification.

关键词： CBERS-02 cloud removal surface reflectance mean reflectance matching.

Magma underplating and Hannuoba present crust-mantle transitional zone composition: Xenolith petrological and geochemical evidence

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Science china earth {2. 2005年第8期48卷 1089-1105页

作者： FAN Qicheng1,2. ZHANG Hongfu1, SUI Jianli1, ZHAI Mingguo1, SUN Qian2.& LI Ni2.1. institute of Geology and Geophysics, chinese Academy of {2., Beijing 10002., china 2. institute of Geology, china Seismological Bureau, Beijing 10002., china institute of Geology and Geophysics Chinese Academy of Sciences Beijing China institute of Geology China Seismological Bureau Beijing China

On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic.

关键词： magma underplating, xenolith petrology, geochemistry, cust-mantle boundary constituent, Hannuoba.