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Science china Earth sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of Geography, Nanjing institute of Meteorology, Nanjing 2.0044, china 2. institute of Geographic {3. and natural resources research, chinese academy of sciences, Beijing 100101, china Department of Geography Nanjing Institute of Meteorology Nanjing 210044 China Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 3. years data from 43. weather stations and 512.hydrological stations in{2., the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

Thresholds of geographic environmental elements in sediment yield of drainage basins

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Science china Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan institute of Geographic sciences and {2. {3. research, chinese academy of sciences, Beijing 100101, china institute of Forestry Science, chinese academy of Forestry Science, Beijing 100091, china research Center for Eco-Environment sciences, chinese academy of sciences, Beijing 100085, china Computing institute of Science and Engineering, North china Electric Power University, Beijing 102.06, china institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing China institute of Forestry Science Chinese Academy of Forestry Science Beijing China research Center for Eco-Environment sciences Chinese Academy of Sciences Beijing China Computing institute of Science and Engineering North China Electric Power University Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological sciences) 2004年第Z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2. WANG Yu3.& WANG Hongrui1 1. Beijing Normal University, Beijing 100875, china 2. {2. of Geographic Science and natural {3., chinese academy of sciences, Beijing 100101, china 3. Reconnaissance, Planning, Design and research {2., YRCC, Zhengzhou 450003. china Beijing Normal University Beijing China institute of Geographic Science and natural {2. Chinese Academy of Sciences Beijing China Reconnaissance Planning Design and Research Institute YRCC Zhengzhou China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science china(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2. GAO Yanhua1,3. CHENG Yu1,3. WEI Zheng1,3. XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese academy of sciences, Beijing 100101, china 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.002., china 3. Graduate University of chinese academy of sciences, Beijing 10003., china 4. Beijing {12. institute of Uranium Geology, Beijing 100875, china 5. institute of Geographic sciences and natural resources {12., chinese academy of sciences, Beijing 100101, china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate University Chinese Academy of Sciences Beijing 100039 China Beijing research institute of Uranium Geology Beijing 100875 China institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Ecological hydraulic radius model to calculate instream flow requirements for transporting sediment in the western water transfer region

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Science china(Technological sciences) 2009年第11期52卷 3401-3405页

作者： MEN BaoHui1 & LIU ChangMing2.1 Renewable Energy institute, North china Electric Power University, Beijing 102.06, china 2.Key Laboratory of Water Cycle and Related Land Surface Process, institute of geographical sciences and natural resources research, chinese academy of sciences, Beijing 100101, china Renewable Energy institute North China Electric Power University Beijing China Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Transporting sediment is a natural function of the river. To maintain the normal evolution of the river certain amount of water flow is required, which is called the instream flow requirements for transporting sediment (IFRTS). We defined the permitting flow velocity by the conception of IFRTS, and also put forward the ecological hydraulic radius model (EHRM) to estimate IFRTS. The calculating process of EHRM is explained by the example of Daofu Hydrological Station on Xianshui branch of Yalong River in the west line first-stage construction of South-North Water Transfer Project. The result shows that the IFRTS occupied 2..7%―59.5% of annual mean discharge in flood season, the average of IFRTS was about 100.2.m3.s during 1966―1987, it is close to the IFRTS 90 m3.s calculated by IFRTS conception. Hence, it is feasible to use EHRM to calculate IFRTS.

关键词： ecological hydraulic radius model (EHRM) instream flow requirements for transporting sediment (IFRTS) permitting flow velocity ecological hydraulic radius for transporting sediment

Continuous wavelet transform and discrete multi-resolution analysis of surface fluxes and atmospheric stability

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Progress in natural Science:Materials International 2006年第4期16卷 403-409页

作者： JIANG Zhaoyang, YU Qiang, WANG Tianduo, SUN Xiaomin and ZHANG Renhua Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 2.00{2., china institute of Geographic sciences and natural resources research, chinese academy of sciences, Beijing 100101, china Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing 100101 China

Variations of land surface fluxes of sensible heat (H), latent heat (LE), and CO2.F-CO2. obtained from the eddy-co-variance measurements above a winter wheat field from March 3. to April 2., 2.01 have been studied at scales ranging from 10 minutes to days. Wavelet transform is used in the analysis of land surface fluxes and atmospheric stability (ξ) calculated from the measurements to reveal the changes in land surface fluxes in hours to days scales. The main results are: (1) Concise and compact information about the fluxes, net radiation (Rn), temperature ( T) and ξ in the scale-time domain are extracted from the data by continuous wavelet analysis, and 1 day, 0.5 day and short-period (shorter than 0.5 day) components are revealed. Continuous wavelet coefficients can be used to characterize periodic components of changes in fluxes and ξ. (2. Discrete-time multi-resolution analysis can be used to concentrate total energy variance of time series of the measurements to a small number of coefficients, plotting the relative energy distribution to get several meaningful characteristics of the data. (3. Under neutral atmospheric conditions, the relative energy distributions of the Haar multi-resolution analysis of the three non-dimensional coefficients ( T/T* , q/q * and c/c * ) display clear similarities.

关键词： atmospheric stability flux continuous wavelet transform multi-resolution wavelet analysis.

Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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chinese Science Bulletin 2009年第13期54卷 2300-2308页

作者： CHEN Jin1,2.3.WANG LiLi1,4,5,ZHU HaiFeng1 & WU Pu1 1 institute of Geographic {2. and natural {3. research,chinese academy of {2.,Beijing 100101,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3.institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of {2.,Beijing 100044,china 4 institute of Tibetan Plateau research,chinese academy of {2.,Beijing 100085,china 5 institute of Desert and Meteorology,china Meteorological Administration,ürümqi 83.002.china institute of Geographic sciences and {2. {3. research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China institute of Desert and Meteorology China Meteorological Administration Ürümqi China

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2.00,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2. of the *** reconstructed results indicated a cold span of 153.years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

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

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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,{2., Urumqi 83.011, china 2. institute of geographical and resources sciences,{2., Beijing 100101, china 3. Urumqi Meteorological-satellite Land Station, Urumqi 83.011, china 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 83.011, china Correspondence should be addressed to Chen Xi Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China institute of geographical and {2. {3. 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, china, 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 {2. 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.

Astronomical function and date of the Taosi observatory

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1, CHEN MeiDong2.& LIU CiYuan3.1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012.{2. 2.institute for the History of {3. Science, chinese academy of sciences, Beijing 100010,{2. 3.National Time Service Center, chinese academy of sciences, Xi’an 710600,{2. National Astronomical Observatories Chinese Academy of Sciences Beijing China institute for the History of natural Science Chinese Academy of Sciences Beijing China National Time Service Center Chinese Academy of Sciences Xi’an China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1,which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1 was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2.and E12.was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 14C analysis archeologists dated the site to about 2.00 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E12.just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1 is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth sciences and {2. resources,{3. University of Geosciences, Beijing 100083.{3. 2. Faculty of Earth sciences,{3. University of Geosciences, Wuhan 43.074,{3. 3. Beijing SHRIMP Center, institute of Geology, chinese academy of Geological sciences, Beijing 10003.,{3. Faculty of Earth sciences and natural {2. China University of Geosciences Beijing China Faculty of Earth sciences China University of Geosciences Wuhan China Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.