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Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South China

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Science China earth sciences 2008年第11期51卷 1589-1600页

作者： ZHANG Yang1 & HE WeiHong1,2.1 Faculty of earth sciences, China University of Geosciences, Wuhan 430074, China 2.Key Laboratory of Biogeology and environmental Geology of Ministry of Education, China University of Geosciences, Wuhan 430074, China Faculty of earth sciences China University of Geosciences Wuhan China Key Laboratory of Biogeology and environmental Geology of Ministry of Education China University of Geosciences Wuhan China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South China.

关键词： brachiopod ornamentation size Permian South China

Quantitative relationships between vegetation and several pollen taxa in surface soil from North China

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Chinese Science Bulletin 2000年第16期45卷 1519-1523页

作者： LI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and environmental sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of sciences, Beijing 100093, China 3. school of Urban and environmental sciences, Northeast Normal University, Changchun 13002., China Correspondence should be addressed to Li Yiyin Department of Urbon and environmental sciences Peking University Beijing China school of Urban and environmental {2. Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation Northeast China Transect (NECT).

Dipole anomaly in the Arctic atmosphere and winter Arctic sea ice motion

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Science China earth sciences 2005年第9期48卷 1529-1536页

作者： WU Bingyi1, ZHANG Renhe1 & WANG Jia2.1. Chinese Academy of Meteorological sciences, Beijing 100081, China 2. International Arctic Research Center, University of Alaska Fairbanks, AK 99775, USA Chinese Academy of Meteorological sciences Beijing China International Arctic Research Center University of Alaska Fairbanks USA

This paper investigates a previously-ignored atmospheric circulation anomaly-di- pole structure anomaly in the arctic atmosphere, and its relationship with the winter sea ice mo- tion, based on analyses of the International Arctic Buoy Programme Data (1979―1998) and datasets from the national Center for {2. Prediction (NCEP) and the national Center for Atmospheric Research (NCAR) for the period of 1960―2.02. The dipole structure anomaly is the second-leading mode of EOF of monthly mean SLP north of 70°N during the winter season (Oct.―Mar.), which accounts for 13% of the variance. One of its two anomaly centers is over the Canadian Archipelago; the other is situated over northern Eurasia and the Siberian marginal seas. Due to the dipole structure anomaly’s strong meridionality, it becomes an important mechanism to drive both anomalous sea ice export out of the Arctic Basin and cold air outbreaks into the Barents Sea, the Nordic Seas and northern Europe.

关键词： dipole anomaly, winter season, Arctic, sea ice motion, sea ice export.

Separation of Red (Y_2._3:Eu^(3+)), Blue (BaMgAl_(10)O_(17):Eu^(2.)) and Green (CeMgAl_(10)O_(17):Tb^3) Rare earth Phosphors by Liquid/Liquid Extraction

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Journal of Wuhan University of Technology(Materials Science) 2009年第4期24卷 603-607页

作者：梅光军 school of Resource and environmental Engineering Wuhan University of Technology

A novel process for separation of red （Y2.3：Eu^3＋）, blue（BaMgAl10O17：Eu^2.） and green （CeMgAl10O17：Tb^3） rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively from an aqueous solution using a chelating collector 2.thenoyltrifluoroacetone （TTA） dissolved in heptane at alkaline pH condition, then, chloroform was used for extracting the green powder into organic phase. The red phosphor remains in aqueous phase with potassium sodium tartrate depressant （PST）. Therefore, three phosphors can be separated successfully from their artificial mixtures by liquid/liquid extraction, and grades and recovery of separated products reach respectively as follows： red is 96.9% and 95.2., blue is 82.7% and 98.8%, green is 94.6% and 82.6%.

关键词： rare earth phosphor solid-solid separation liquid/liquid extraction

environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,China

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State Key Laboratory of Vegetation and environmental Change,Institute of Botany,Chinese Academy of sciences,Beijing 100093, China 2.{2. of Geographic and Oceanographic sciences,Nanjing University,Nanjing 2.0093,China State Key Laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing China school of Geographic and Oceanographic sciences Nanjing University Nanjing China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

A HISTORICAL EXAMINATION ON LAND DESERTIFICATION IN NORTH CHINA

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Chinese Geographical Science 2001年第2期11卷 115-119页

作者： YAN Ting-zhen1 , CHEN Xi-bo2., HAN Guang-hui1 (1. Department of Urban and environmental sciences, Peking University, Beijing 100871, P. R. China 2. {2. of Humanities and Social sciences, Dalian University of Technology, Dalian 11602., P.R. China) Department of Urban and environmental sciences Peking University Beijing P. R. China school of Humanities and Social sciences Dalian University of Technology Dalian P. R. China

Desertification control has been facing severe situations in the interlocking area between cultivated land and grazing land in North China since the Qing Dynasty because of unreasonable land utilization. The paper analyzes the policies of all the previous governments to open up land, and examines the historical and geographical background and process by means of historical records. We consider that causes of the area of land desertification to extend are increase of farming migrants, the change of life style of Mongol and weather and land conditions. In order to control the spread of land desertification, we suggest the level of the government to make policies should be improved, the number of farming migrants should be controlled, the Government′s general and specific polices should be actively publicized, and investment in agriculture should be increased.

关键词： farming migrants life style of Mongol weather and land conditions land desertification Qing Dynasty

Petrology and tectonic significance of the early Mesozoic granulite xenoliths from the eastern Inner Mongolia, China

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Science China earth sciences 2011年第10期54卷 1484-1491页

作者： SHAO JiAn 1,2.& WEI ChunJing 1 1 The Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education school of earth and Space {2., Peking University, Beijing 100871, China 2.Key Laboratory of Mineral Resources, Chinese Academy of {2., Beijing 10002., China The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education school of earth and Space {2. Peking University Beijing China Key Laboratory of Mineral Resources Chinese Academy of Sciences Beijing China

Granulite xenoliths are found in the early Mesozoic diorite intrusions from Chifeng and Ningcheng areas, eastern Inner Mongolia. The granulites are granoblastic and weakly gneissic with mineral assemblage of hypersthene, diopside, plagioclase and minor biotite, amphibole and ilmenite. Some samples contain the intergrowth composed of labradorite and vermicular hypersthene, and some coarse-grained plagioclases of andesine and labradorite composition occasionally develop bytownite rims with vermicular hypersthene, indicating a possible presence of garnet. Presence of blastogabbroic texture and hypersthene with diopside exsolution lamellae in some samples suggests that the protolith of the granulite is norite or gabbro. On the basis of metamorphic research and thermobaric calculation, the evolution of the granulite xenoliths is summarized into the following stages: (1) Isobaric cooling of underplated noritic or gabbroic magma in the lower crust led to the formation of probable garnet-bearing medium-high pressure granulite. (2. These higher pressure granulites were adiabatically uplifted to upper crust by dioritic magma and transformed to low pressure two-pyroxene granulite during an isothermal decompression. (3) The two-pyroxene granulite underwent retrograde metamorphism of different degrees during an isobaric cooling process as a result of crystallization and cooling of the dioritic magma. The pyroxenite-dominated cumulates and the medium-high pressure granulites may have rejuvenated the lower crust during the early Mesozoic.

关键词： early Mesozoic granulite xenolith lower crust North China Craton

Subchronic toxicological effects of aquatic nitrobenzene on Medaka and Chinese rare minnow

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Science China Chemistry 2007年第5期50卷 707-717页

作者： ZHOU QunFang1, FU JianJie1,2. MENG HaiZhen1,2. ZHU XueYan1,2. JIANG GuiBin1, ZHANG JianBin1, LIU JieMin2.& SHI GuoQing2.1 State Key Laboratory of environmental Chemistry and Ecotoxicology, Research Center for Eco-environmental {2., Chinese Academy of {2., Beijing 100085, China 2.Department of Chemistry, school of Applied Science, University of Science and Technology Beijing, Beijing 100083, China State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing China Department of Chemistry School of Applied Science University of Science and Technology Beijing Beijing China

Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and Chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The Chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismu- tase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholi- nesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitro- benzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

关键词： nitrobenzene, Medaka, Chinese rare minnow, bioaccumulation, elimination, molecular biomarkers, histopathological effects

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1,2., Nie Baochi 3, Wang Lin 1 & Wu Wei 1 1. school of environmental and Biological Science and Technology, Dalian University of Technology, Dalian 11602., China 2. Urban and environmental school, Liaoning Normal University, Dalian 11602., China 3. Shenyang Buraue of Water Resources, Shenyang 110013, China. school of environmental and Biological Science and Technology Oalian University of Technology Oalian 116024 China Urban and environmental school Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water Resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences