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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 sciences, Nanjing 2.0008,{2. 2. Graduate School of chinese academy of sciences, Beijing 100039,{2. 1. Taihu Lake Laboratory for Ecosystem Research Nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. Graduate School of chinese academy of sciences 100039 Beijing 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.

Natural abundant ^(15)N NMR detection of polypeptide and protein

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chinese Science Bulletin 1997年第19期42卷 1606-1611页

作者： HUANG He and MAO xi’anWuhan institute of Physics, chinese academy of sciences, Wuhan 430071,{2. Wuhan institute of Physics Chinese Academy of Sciences Wuhan China

THE ~15N NMR study is of general interest in the analysis of the protein conformations in solu-tions. When NMR is applied to the conformation study of macrobiomolecules, a heteronuclearmultiple quantum coherence (HMQC) spectrum of ~15N is usually measured first, so that theamide protons are assigned before other experiments, such as the total correlation

关键词： polypeptide and protein natural abundant 15N NMR heteronuclear multiple quantum coherence spectrum.

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science china earth {2. 2005年第5期48卷 585-600页

作者： YANG Wencai 1 , YANG Wuyang 1 , JIN Zhenmin 2.& CHENG Zhenyan 1 1. institute of Geology, chinese {2. of Geological sciences, Beijing 100037, china 2. china University of Geosciences, Wuhan 430074, china 1. chinese academy of Geological {2. Institute of Geology 100037 Beijing China 2. china University of Geosciences 430074 Wuhan China

Calibration of seismic reflectors appearing in the crust of the chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 11 km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu china, calibration of reflectors, lithospheric fabrics.

Simultaneous Strain and Temperature Measurement with Optical Fiber Gratings: Error Analysis

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chinese Journal of Lasers 2000年第3期9卷 52-57页

作者： JIA Hongzhi LI Yulin (xi’an institute of Optics & Precision Mechanics, The chinese academy of sciences, xi’an 710068,{2.) 中科院西安光学精密机械所陕西西安

Many schemes designed to simultaneously measure strain and t emperature with optical fiber grating sensors have been reported in recent years. In this paper, the influence of systematic errors associated with the measurement process is analyzed and the error formulas are derived. The results are applied to a range of techniques that are of current interest in the literature. The performance of these schemes is contrasted with respect to the influence of wavelength measurement error and sensitivity matrix error.

关键词： fiber grating sensors strain measurement temperature measurement error analysis

Precipitation Pulses and Soil CO_2.Emission in Desert Shrubland of Artemisia ordosica on the Ordos Plateau of Inner Mongolia,china

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Pedosphere 2009年第6期19卷 799-807页

作者： JIN Zhao DONG Yun-She QI Yu-Chun M. DOMROES institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 （China） institute of Geography Mainz University Mainz 55099 （Germany）

Precipitation is the major driver of ecosystem functions and processes in semiarid and arid regions. In such waterlimited ecosystems, pulsed water inputs directly control the belowground processes through a series of soil drying and rewetting cycles. To investigate the effects of sporadic addition of water on soil CO2.effux, an artificial precipitation event （3 mm） was applied to a desert shrub ecosystem in the Mu Us Sand Land of the Ordos Plateau in china. Soil respiration rate increased 2.8 4.1 times immediately after adding water in the field, and then it returned to background level within 48 h. During the experiment, soil CO2.production was between 2.047.0 and 7 383.0 mg m^-2. In the shrubland, soil respiration responses showed spatial variations, having stronger pulse effects beneath the shrubs than in the interplant spaces. The spatial variation of the soil respiration responses was closely related with the heterogeneity of soil substrate availability. Apart from precipitation, soil organic carbon and total nitrogen pool were also identified as determinants of soil CO2.loss in desert ecosystems.

关键词： desert shrub ecosystem Mu Us sand land soil respiration response water addition

Discovery of eclogite and its geological significance in Qiangtang area, central Tibet

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Science Bulletin 2006年第9期51卷 1095-1100页

作者： LI Cai1, ZHAI Qingguo2. DONG Yongsheng1 & HUANG xiaopeng11. College of earth sciences, Jilin University, Changchun 130061,{2. 2. institute of Geology, chinese academy of Geological sciences, Bei- jing 100037,{2. College of earth sciences Jilin University Changchun 130061 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 40Ar/39Ar age of 2.0 Ma and a phengite 40Ar/39Ar age of 2.1.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- chinese epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.

关键词： Qianghai-Tibet Plateau Qiangtang eclogite tectonics.

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1, ZHAO Zhenhua 1, SHI Manquan 1, YANG Shufeng 2.and CHEN Hanlin 2.1. Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640,{2. 2. Department of earth sciences, Zhejiang University, Hangzhou 31002.,{2. Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of earth sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 2.1 MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china earth {2. 2005年第9期48卷 1463-1469页

作者： xiE Shucheng1,HUANG Junhua1,WANG Hongmei2.YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4 1. Faculty of earth Science,china University of Geo{2.,Wuhan 430074,china 2. School of environmental Studies,china University of Geo{2.,Wuhan 430074,china 3. SKLLQG,institute of earth environment,chinese {12. of {2.,xi’an 710075,china 4. Department of Geology and Geophysics,University of Minnesota,MN55455,USA 1. Faculty of earth Science China University of Geosciences 430074 Wuhan China 2. School of environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C2. in carbon number, maximizing at C16, with a second dominance at C2.. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C2.). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2.ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china earth {2. 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3, LI Jiliang1, SUN Shanxue1 & WANG xinzheng1 1. institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,{2. 2. institute of Geophysics, chinese Seismological Bureau, Beijing 100081,{2. 3. institute of Deposition Resource, chinese academy of Geological sciences, Beijing 100037,{2. 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting