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Research on the method for retrieving soil moisture using thermal inertia model

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Science china earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information college, South china Agricultural university, Guangzhou 510642, china 2. Graduate university of Chinese Academy of sciences, beijing 100049, china 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science china earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3. ZHANG RenHe2, SUN ShuFen1, BIAN LinGen2, XIAO CunDe4,2 & ZHANG TingJun5 1 Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china 2 Chinese Academy of Meteorological sciences, beijing 100081, china 3.Graduate university of Chinese Academy of sciences, beijing 100049, china 4 Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 73.000, china 5 The National Snow and Ice Data Center, university of Colorado, Boulder, CO 803.9-0449, USA 1. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3. 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of Chemistry and Chemical Engineering,Graduate university of Chinese Academy of sciences,{3. 100049,china 1. college of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

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天山北麓流域面积高度积分特征及其构造意义

山地学报 2009年第3期27卷 285-292页

作者：赵洪壮李有利杨景春司苏沛北京大学城市与环境学院北京大学地理科学中心地表过程分析与模拟教育部重点实验室

提取了天山北麓河流水系流域的常规地貌计量指标(盆地大小、面积和高差)以及面积高度积分,通过对流域面积高度积分曲线形态特征、面积高度积分值的分析,结合区域地质构造活动,探讨了面积高度积分对板内再生造山带新构造活动的指示意义... 详细信息

提取了天山北麓河流水系流域的常规地貌计量指标(盆地大小、面积和高差)以及面积高度积分,通过对流域面积高度积分曲线形态特征、面积高度积分值的分析,结合区域地质构造活动,探讨了面积高度积分对板内再生造山带新构造活动的指示意义以及天山北麓流域的地貌发育过程。研究表明,北天山流域的次集水盆地面积高度积分与次集水盆地的面积和高差都没有相关性,堆积作用和轻微构造抬升作用都会影响冲积扇区次集水盆地,使其面积高度积分值偏高。河流面积高度积分曲线形态和面积高度积分值在空间分布上的差异,反映了天山北麓3.逆断裂褶皱带的不同的构造活动特征。面积高度积分曲线的循环形态特征,揭示了强烈构造运动与河流剥蚀作用影响面积高度曲线形态发育的动态演绎过程。

关键词：面积高度积分构造运动河流天山

Interdecadal change in Western Pacific Subtropical High and climatic effects

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Journal of Geographical sciences 2002年第2期12卷 79-86页

作者： HE Xue-zhao1, GONG Dao-yi1,2 (1. laboratory of environmental Change and Natural Disaster Research, Institute of Resources Science, beijing Normal {3., beijing 100875, china 2. School of earth and environmental sciences, Seoul National {3. laboratory of environmental Change and Natural Disaster Research Institute of Resources Science 北京 100875 School of earth and environmental sciences Seoul National University 韩国 Seoul 151-742

Western North Pacific Subtropical High is a very important atmospheric circulation system influencing the summer climate over eastern china. Its interdecadal change is analyzed in this study. There is a significant decadal shift in about 1979/1980. Since 1980, the Western North Pacific Subtropical High has enlarged, intensified, and shifted southwestward. This change gives rise to an anti-cyclonic circulation anomaly over the region from the South china Sea to western Pacific and thus causes wet anomalies over the Yangtze River valley. During the summers of 1980-1999, the precipitation is 63.9 mm above normal, while during 1958-1979 it is 27.3.mm below normal. The difference is significant at the 99% confidence level as a t-test shown. The southwestward expanding of the Western North Pacific Subtropical High also leads to a significant warming in southern china, during 1980-1999 the summer mean temperature is 0.3.篊 warmer than that of the period 1958-1979. The strong warming is primarily due to the clearer skies associated with the stronger downward air motion as the Western North Pacific Subtropical High expanding to the west and controlling southern china. It is also found that the relative percentage of tropical cyclones in the regions south of 20篘 is decreasing since the 1980s, but in the regions north of 20篘 that is increasing at the same time. The Western North Pacific Subtropical High responds significantly to sea surface temperature of the tropical eastern Pacific with a lag of one-two seasons and simultaneously to sea surface temperature of the tropical Indian Ocean. The changes in the sea surface temperatures are mainly responsible for the interdecadal variability of the Western North Pacific Subtropical High.

关键词： Western Pacific Subtropical High interdecadal change climate change

Study on the simulation of transparency of Lake Taihu under different hydrodynamic conditions

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Science china earth sciences 2006年第z1期49卷 162-175页

作者： PANG Yong, LI Yiping & LUO Liancong college of environmental Science and Engineering, Hohai university, Nanjing 210098,{3. Nanjing Institute of Geography & Limnology, Chinese Academy of sciences, Nanjing 210098,{3. Hohai Univ Coll Environm Sci & Engn Nanjing 210098 Peoples R China Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210098 Peoples R China

It was indicated in this study that there were negative relations between the concentrations of suspended solid (SS) and transparency according to the analysis of measured data of Lake Taihu. Their relations in pervious studies were reviewed, which showed that the changes of transparency in Lake Taihu could be reflected by simulating suspended solid concentration (SSC). Measured data showed that the changes of SSC with wind speed were similar at different water *** increased with the increasing of wind speed. Both wave and lake current of Lake Taihu had positive relations with SSC. However, wave was the main factor affecting sediment suspension, while flow took the second place. In this study, a numerical model coupling lake current, wave and SSC of Lake Taihu was developed. In the SS model, the combined effects of wave and current were *** amounts of suspended and deposited sediments near the lake bed surface layer were treated separately. The stochastic characteristics of turbulent flow pulsation near lake beds were also considered, and the start-up conditions of sediment suspension were introduced to the model. The model elucidated the mutual exchange processes between sediment particles in SS and active sediments within and on the bed surface layer. Simulated results showed that lake current had relatively significant effects on the SSC at littoral areas of Lake Taihu, while SSC at the central area of the lake was mainly influenced by wave. The changes of transparency with SSC were simulated for Lake Taihu using this model. Calculated results were validated by measured data with good fitness, which indicated that the model is basically suitable for the simulation and prediction of transparency of Lake Taihu.

关键词： transparency suspended solid hydrodynamlc sediment suspension model.

Validation of Dietary Intake of Dichlorodiphenyltrichloroethane and Metabolites in Two Populations from beijing and Shenyang,china Based on the Residuals in Human Milk

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Validation of Dietary Intake of Dichlorodiphenyltrichloroeth...

Integrated erosion control measures and environmental effects in rocky mountainous areas in northern china

第五届全国环境化学大会

作者： Shu Tao~*,Yanxin Yu~+,Wenxin Liu~+,Xuejun Wang~+,Jun Cao~+,Bengang Li~+,Xiaoxia Lu~+,Ming H Wong (laboratory for earth surface {3.,college of Urban and environmental sciences,peking university,beijing 100871,china,Croucher Institute for environmental sciences,and Department of Biology,Hong Kong Baptist university,Kowloon Tong,Hong Kong,PR china

＜正＞This paper presents the results of an investigation on association between dietary intakes and human milk concentrations of dichlorodiphenyltrichloroethane and metabolites（DDTs）of two populations from beijing and Shenyang,*** analyzed human milk samples from 76 women and 287 composite food samples covering major food categories for concentrations of *** also collected information on food consumptions and calculated dietary intakes of DDTs of the participants on individual *** median values of the measured DDTs in human

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International Journal of Sediment Research 2010年第3期25卷 294-303页

作者： HE Jijun1, CAI Qiangguo2, LI Guoqiang3. and WANG Zhongke41 Ph. D, Lecturer, Capital Normal university, Elementary Educational college, beijing 100048,{3. State Key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Water and Soil Conservation, Chinese Academy of sciences and Ministry of Water Resources, Yangling 712100 Shanxi,{3.. 2 Prof., Institute of Geographical sciences and Natural Resources Research, Key laboratory of Water Cycle and Related Land surface processes, CAS, beijing 100101,{3., 3.Graduate student, Huazhong Agricultural university, college of Resources and Environment, wuhan 43.070,{3. 4 Prof., Zhangjiakou Supervision Station of Water Conservancy Project, Zhangjiakou Supervision Sub-station of Soil and Water Conservation and environment, Zhangjiakou 075000,{3. [a] Ph. D Lecturer Capital Normal University Elementary Educational College Beijing 100048 China State Key laboratory of Soil Erosion Dryland Farming on the Loess Plateau Institute of Water Soil Conservation Chinese Academy of Sciences Ministry of Water Resources Yangling 712100 Shanxi China [b] Prof. Institute of Geographical Sciences Natural Resources Research Key Laboratory of Water Cycle Related Land surface processes CAS Beijing 100101 China [c] Graduate student Huazhong Agricultural University College of Resources Environment wuhan 430070 China [d] Prof. Zhangjiakou Supervision Station of Water Conservancy Project Zhangjiakou Supervision Sub-station of Soil Water Conservation environment Zhangjiakou 075000 China

Based on observations of runoff plots and field investigations of gully cross-sections, impacts of various soil and water conservation measures on runoff and sediment yield are analyzed for different rainfall conditions. The results show that antecedent rainfall and rainfall intensity are the main factors affecting the runoff and soil erosion processes. Rainfall events with antecedent rainfall can produce high runoff and sediment yield. Large differences in the characteristics of two rainfall events will result in greater variations of total runoff and sediment yield from the same runoff plot. Under the same soil control measure and rainfall condition, soil and water conservation measures can reduce the impacts of antecedent rainfall and rainfall intensity on runoff and soil erosion. Among various measures, level terrace seems to be the greatest for soil conservation purposes. Combining with engineering measures,Vegetation measures is also effective in controlling runoff and soil erosion. In the initial stage of vegetation enclosure measures, engineering measure is necessary to improve the environment for ecological recovery. Gully head protection can control gully erosion effectively, but the effectiveness of gully head protection would be reduced when rainfall intensity increases. Therefore, the design of a gully head protection structure must be based on local hydrological conditions.

关键词： Rainfall character Antecedent rainfall Gully head protection Cumulated erosion amount

Late Cenozoic high-resolution magnetostratigraphy in the Kunlun Pass Basin and its implications for the uplift of the northern Tibetan Plateau

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Science Bulletin 2005年第17期 98-108页

作者： SONG Chunhui1, GAO Dongling1,2, FANG Xiaomin3.1, CUI Zhijiu4, LI Jijun1, YANG Shengli3. JIN Hongbo1, Douglas Burbank5 & Joseph L. Kirschvink6 1. moe Key laboratory of Western china’s {3. Systems (Lanzhou university), Ministry of Education & college of earth and Environment sciences, Lanzhou university, Lanzhou 73.000, china 2. Qinghai Institute of Salt Lakes, Chinese Academy of sciences, Qing-hai 810008, china 3. Institute of Tibetan Plateau Research, Chinese Academy of sciences, {13. 100085, china 4. college of {3. sciences, peking university, beijing 100871, china 5. Department of Geological sciences, university of California, Santa Barbara, USA 6. Paleomagnetics laboratory, Division of Geological and Planetary sciences, California Institute of Technology, Pasadena, CA 91125, USA

The Kunlun Pass Basin, located in the middle of the eastern Kunlun Mountains, received relatively con-tinuous late Cenozoic sediments from the surrounding mountains, archiving great information to understand the deformation and uplift histories of the northern Tibetan Pla-teau. The Kunlun-Yellow River Movement, identified from the tectonomorphologic and sedimentary evolution of the Kunlun Pass Basin by Cui Zhijiu et al. （1997, 1998）, is roughly coincident with many important global and Plateau climatic and environmental events, becoming a crucial time interval to understand tectonic-climatic interactions. How-ever, the ages used to constrict the events remain great un-certainty. Here, we present the results of detailed magneto-stratigraphy of the late Cenozoic sediments in the Kunlun Pass Basin, which show the basin sediments were formed between about 3.6 Ma and 0.5 Ma and the Kunlun-Yellow River Movement occurred at 1.2 to0.78 Ma. The lithology, sedimentary facies and lithofacies associations divide the basin into five stages of tectonosedimentary evolution, indi-cating the northern Tibetan Plateau having experienced five episodes of tectonic uplifts at3.6, 2.69-2.58, 1.77, 1.2, 0.87 and0.78 Ma since the Pliocene.

关键词： magnetostratigraphy Kunlun Pass Basin Late Cenozoic Tibetan Plateau.