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Ecological response to the climate change on the northern slope of the Tianshan mountains in Xinjiang

Science china Earth sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2. ZHOU Kefa1, LOU Shaoping3 & YE Minquan4 1. Xinjiang Institute of Ecology and Geography, chinese Academy of sciences, Urumqi 830011, {2. 2. Institute of Geographical and Resources sciences, chinese Academy of sciences, Beijing 100101, {2. 3. Urumqi Meteorological-satellite Land Station, Urumqi 830011, {2. 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 830011, {2. Correspondence should be addressed to Chen Xi Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Institute of Geographical and Resources sciences Chinese Academy of Sciences Beijing China Urumqi Meteorological-satellite Land Station Urumqi China Seismological Bureau of Xinjiang Uygur Autonomous Region Urümqi China

The Tianshan mountains is a high and huge mountain body lying across the central part of Xinjiang, {2., and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2. the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3) the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

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Relationship between Surface Pollen and Modern Vegetation in Southwestern china

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Journal of mountain Science 2010年第2期7卷 176-186页

作者： PAN Tao DAI Erfu and WU Shaohong Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese Academy of sciences BeO'ing 100049 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant quadrats,the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal range-gorge region (LRGR) in Southwestern china.R-values (referring to pollen assemblages) are calculated with pollen percentage and plant *** coefficients of similarity between pollen and vegetation are *** results show that the pollen assemblages on surface soil of all vegetation zones can basically represent the native vegetation,but the pollen assemblages are not fully according with the *** is due to the influencing factors including pollen preservation ability,pollen production,amount of exotic pollen and pollen *** pollen representation in surface soil is different in families and *** pollen of woody plants such as Pinus,Tsuga,Alnus,Fagus and Castanopsis are over-representative,but those of Quercus,Carpinus Myrica,Elaeocarpaceae,Ericaceae,Theaceae and Llex are underrepresentative;the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative,while those of others including Gramineae and Araliaceae are *** R-values of the same taxon pollen in different vegetation zones are different,depending on their distances from the pollen *** coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%,which indicate again that the surface soil pollen and spores assemblages can represent the *** is concluded that there is a good corresponding relationship between surface pollen assemblages and native vegetation in LRGR,and it is of great significance for reconstructing the past vegetation and paleoclimate using quantitative fossil pollen data in this region.

关键词： Longitudinal range-gorge region (LRGR) Pollen assemblage Vegetation R-value Coefficient of similarity

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MICROWAVE OBSERVATION HIGHLIGHTS OF AR562.

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天文研究与技术 1990年第4期 189-192页

作者： Zhou Aihua Xu FuyingPurple mountain {2., chinese Academy of sciences nanjing, 2.0008, china

Active Region 562. was extraordinary for both its flare production rate in asunsport region with moderate area and for the largest X—ray flare,ever observed by theGOES spacecraft,an estimated X2. at 0118UT on 16 ***,... 详细信息

关键词： hemisphere moderate extraordinary spacecraft burst Polarization Solar everyday exceed rarely

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^(137)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-137(137 Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 137 Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 137 Cs redistribution in a karst area of Southwest *** results indicated that the 137 Cs inventories of the surface soil on the slope studied were much lower than that of the local 137 Cs reference inventory and the 137 Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 137 Cs inventories was characterized by considerable *** high 137 Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 137 Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 137 *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 137 Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^137Cs fallout, ^137Cs inventory karst area runoff

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THE MOTION PROPERTIES OF THE STARS CONFINED TO THE SYMMETRIC AXIS OF AN OSCILLATION KUZMIN DISK

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南京大学学报(自然科学) 1997年第4期 151-153页

作者： Fu Yanning 1,2. \ \ Sun Yisui 1) ( 1) Department of Astronomy, nanjing University, 2.0008, nanjing, PRC 2. Purple mountain observatory, Academia Sinica, 2.0008, nanjing, PRC)

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）Ｄ... 详细信息

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）ＤｅｐａｒｔｍｅｎｔｏｆＡｓｔｒｏｎ...

关键词： celestial mechanics galactic dynamics galaxy oscillation

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The Suitability of Using Leaf Area Index to Quantify Soil Loss under Vegetation Cover

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Journal of mountain Science 2011年第4期8卷 564-570页

作者： ZHANG Wentai YU Dongsheng SHI Xuezheng WANG Hongjie GU Zhujun ZHANG Xiangyan TAN Manzhi State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 21o0o8 China Graduate University of the chinese Academy of sciences Beijing 100039 China School of Bio-Chemical and Environmental Engineering Nanjing Xiaozhuang University Nanjing 211171 China

Soil erosion by water under forest cover is a serious problem in southern china.A comparative study was carried out on the use of leaf area index(LAI) and vegetation fractional coverage(VFC) in quantifying soil loss under vegetation *** types of vegetation with varied LAI and VFC under field conditions were exposed to two rainfall rates(40 mm h-1 and 54 mm h-1) using a portable rainfall *** rate,sediment concentration and soil loss rate were measured at relatively runoff stable *** negative exponential relationship(p 2.= 0.83) and linear relationship(p 2.= 0.84) were obtained between LAI and sediment concentration,while no significant relationship existed between VFC and sediment *** mechanism by which vegetation canopy prevents soil loss was by reducing rainfall kinetic energy and sediment *** could better quantify such a role than ***,neither LAI nor VFC could explain runoff rate or soil loss *** must be taken when using LAI to quantify the role of certain vegetation in soil and water conservation.

关键词： Leaf area index(LAI) Runoff steady state Sediment concentration Simulated rainfall

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Transpiration Rates of Carex Meyeriana in Relation to Micrometerological Factors in a mountain Valley Wetland

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Journal of mountain Science 2009年第3期6卷 293-298页

作者： XU Huifeng JIN Yanming DENG Wei XU Kezhang WANG Zhen College of Agriculture Jilin Agricultural University Changchun 130008 P.R. China. Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610042 P.R. China. University of Nebraska-Board of Regents Lincoln NE 68503-1435 USA

In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai mountain valley in dry (July) and wet (September) of 2.03, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2.s-1) compared to those (varied from 7 to 14 mol·m-2.s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05).

关键词： Micrometerological factors transpiretion rates Carex meyeriana mountain valley wetland

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Numerical simulation of air-water two-phase flow over stepped spillways

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Science china(Technological sciences) 2006年第6期49卷 674-684页

作者： CHENG Xiangju1, CHEN Yongcan1 & LUO Lin2.1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. State Key Laboratory of Hydraulics and mountain River Engineering, Sichuan University, Chengdu 610065, china Department of Hydraulic Engineering Tsinghua University Beijing China State Key Laboratory of Hydraulics and mountain River Engineering Sichuan University Chengdu China

Stepped spillways for significant energy dissipation along the chute have gained interest; popularity among researchers; dam engineers. Due to the complexity of air-water two-phase flow over stepped spillways, the finite volume computational fluid dynamics module of the FLUENT software was used to simulate the main characteristics of the flow. Adopting the RNG k- turbulence model, the mixture flow model for air-water two-phase flow was used to simulate the flow field over stepped spillway with the PISO arithmetic technique. The numerical result successfully reproduced the complex flow over a stepped spillway of an experiment case, including the interaction between entrained air bubbles; cavity recirculation in the skimming flow regime, velocity distribution; the pressure profiles on the step surface as well. The result is helpful for understanding the detailed information about energy dissipation over stepped spillways.

关键词： stepped spillway, mixture model, RNG k-εmodel, air-water two-phase flow.

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The structure of molecular cloud W51 and dense cores ——CO（J=1-0） and HCO+（J=1-0） spectral line mapping

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Science china(Physics,Mechanics & Astronomy) 2005年第2期 42-51页

作者： MA Hongjun, PEI Chunchuan & ZENG QinPurple mountain {2., chinese Academy of sciences, nanjing 2.0008, china

We present a large scale map of about 15′×15′of CO(J=1-0) toward W51 giant molecular cloud (GMC), which covers the most active star-forming region of W51 GMC, and an interferometry HCO+(J=1-0) map of a high spatial resolution (i.e. 8″.7× 6″.1) with a field of view (2.×2.) centered at W51IRS1. A structure model of W51GMC is obtained according to the results of the observations and analyses. The observations demonstrate that some small molecular cores generated by the collision between the W51GMC and the 60—73 km·s-1 foreground cloud are collapsing toward their own centers. In addition, 16 new molecular cores are discovered from the HCO+(J=1-0) map.

关键词： molecular core continuum source star formation.

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Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in china

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Journal of mountain Science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China Graduate University of the chineseAcademy of sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2.08 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method

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