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Indoor imitation experimental study on driving factors of rainfall-runoff process

Science China Earth sciences 2005年第3期48卷 417-428页

作者： ZHANG Shifeng1, LIU Changming 1, XIA Jun1, TAN Ge 1, LI Lin1, LIU Caitang1, ZHOU Changqing 1 & GUO Lei2.1. institute of geographic sciences and natural resources Research, Chinese Academy of sciences, Beijing 100101, China 2. College of Water {2. and Hydropower Engineering, Wuhan University, Wuhan 430072. China 1. institute of geographic sciences and natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. College of Water resources and Hydropower Engineering Wuhan University 430072 Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south China region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north China where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north China region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north China region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north China region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south China region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science China Earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2. WANG Gangsheng1, TAN Ge1, YE Aizhong2.& G. H. Huang3 1. key laboratory of Water Cycle & Related Land Surface Processes,{2. Research, Chinese Academy of sciences, Beijing 100101, China 2. state key laboratory of Water resources & Hydropower Engineering sciences, Wuhan University, Wuhan 430072. China 3. Faculty of Engineering, University of Regina, 3737 Wascana Parkway, Regina, Sask., S4S 0A2. Canada Correspondence should be addressed to Xia Jun 1. key laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. state key {2. of Water resources & Hydropower Engineering sciences Wuhan University 430072 Wuhan China 3. Faculty of Engineering University of Regina 3737 Wascana Parkway S4S 0A2 Sask Regina Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern China and the Chaobai River basin located in the semihumid region of northern China. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different {2. conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

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Estimation of soil organic carbon reservoir in China

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Journal of geographical sciences 2001年第1期11卷 3-13页

作者： WANG Shao-qiang1, ZHOU Cheng-hu1, LI Ke-rang1, ZHU Song-li2. HUANG Fang-hong1 (1.The state key {2. of resources and environment Information system, institute of geographic sciences and natural resources Research, CAS, Beijing 100101, China The state key {2. of resources and environment Information system Institute of Geographic Sciences and Natural Resources Research CAS Beijing China institute of environment Science Beijing Normal University Beijing China

The paper respectively adopted physio-chemical properties of every soil stratum from 2.73 soil profiles of the second national soil survey. The corresponding carbon content of soils is estimated by utilizing conversion coefficient 0.58. In the second soil survey, the total amount of soil organic carbon is about 92..18xl08t and carbon density is about 10.53 kgC/m2.in China according to the area of 877.63x106hm2.surveyed throughout the country. The spatial distribution characteristics of soil organic carbon in China is that the carbon storage increases when latitude increases in eastern China and the carbon storage decreases when longitude reduces in northern China. A transitional zone with great variation in carbon storage exists. Moreover, there is an increasing tendency of carbon density with decrease of latitude in western China. Soil circle is of great significance to global change, but with substantial difference in soil spatial distribution throughout the country. Because the structure of soil is inhomogeneous, it could bring some mistakes in estimating soil carbon reservoirs. It is necessary to farther resolve soil respiration and organic matter conversion and other questions by developing uniform and normal methods of measurement and sampling.

关键词： terrestrial ecosystem global change soil carbon reservoir carbon cycle

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Spatial pattern of land cover change in China's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2.1 state key {2. of environment and resources Information system, institute of geographical sciences and resources Research, Chinese Academy of sciences, Beijing 100101, China 2.Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China Hong Kong Baptist Univ Dept Geog Kowloon Tong Hong Kong Peoples R China Chinese Acad Sci State Key Lab Environm & Resources Informat Syst Inst Geog Sci & Resources Res Beijing 100101 Peoples R China

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of China based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2. the establishment of land cover change classes based on an unification land cover classification theme, (3) the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, China. The results showed the land cover had undergone a remarkable change from 1991 to 2.02.in the study area (the changed area was over 30%). Rapid increase of cropland (12.5%), built-up area (131.4%) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile eco{2. of China’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of China remote sensing human activities

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Characterizing the Mass Elevation Effect across the Tibetan Plateau

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Journal of Mountain Science 2018年第12期15卷 2651-2665页

作者： HAN Fang ZHANG Bai-ping ZHAO Fang WAN Li TAN Jing LIANG Tian School of Civil and Architectural Engineering, Shandong University of Technology institute of geographic {2. and natural resources Research, state key laboratory of resources and environmental Information system, Chinese Academy of {2. College of environment and Planning, Henan University Chinese Research Academy of environmental {2. Beijing Aerospace TITAN Technology Co., Ltd School of Civil and Architectural Engineering Shandong University of TechnologyZibo 255000China institute of geographic {2. and natural resources Research State Key Laboratory of Resources and Environmental Information SystemChinese Academy of SciencesBeijing 100101China College of environment and Planning Henan UniversityKaifeng 455000China Chinese Research Academy of environmental sciences Beijing 100012China Beijing Aerospace TITAN Technology Co. LtdBelling 100083China

It is over 110 years since the term Mass Elevation Effect(MEE) was proposed by A. D. Quervain in 1904. The quantitative study of MEE has been explored in the Tibetan Plateau in recent years; however, the spatial distribution of MEE and its impact on the ecological pattern of the plateau are seldom known. In this study, we used a new method to estimate MEE in different regions of the plateau, and, then analyzed the distribution pattern of MEE, and the relationships among MEE, climate, and the altitudinal distribution of timberlines and snowlines in the Plateau. The main results are as follows:(1) The spatial distribution of MEE in the Tibetan Plateau roughly takes on an eccentric ellipse in northwestsoutheast trend. The Chang Tang Plateau and the middle part of the Kunlun Mountains are the core area of MEE, where occurs the highest MEE of above 11℃; and MEE tends to decreases from this core area northwestward, northeastward and southward;(2. The distance away from the core zone of the plateau is also a very important factor for MEE magnitude, because MEE is obviously higher in the interior than in the exterior of the plateau even with similar mountain base elevation(MBE).(3) The impacts of MEE on the altitudinal distribution of timberlines and snowlines are similar, i.e., the higher the MEE, the higher timberlines and snowlines. The highest timberline(4600–4800 m) appears in the lakes and basins north of the Himalayas and in the upper and middle reach valleys of the Yarlung Zangbo River, where the estimated MEE is 10.2.2.℃–10.6904℃. The highest snowline(6000–62.0 m) occurs in the southwest of the Chang Tang Plateau, where the estimated MEE is 11.2.59°C–11.5488℃.

关键词： Mass Elevation Effect (MEE) Distribution Pattern Timberline Snowline Tibetan Plateau

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Relationship between erosion and sediment yield in drainage basins of loess gully-hilly areas

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Journal of geographical sciences 2001年第1期11卷 71-79页

作者： CHEN Hao (institute of geographic {2. and natural resources Research, CAS, Beijing 100101, China) institute of geographic {2. and natural resources Research CAS Beijing China

From a long-term point of view, the balance between erosion and sediment yield in a drainage system can basically realize, i.e., the delivery ratio can be close to 1. However, substantial variations among individual rainfall events or between annual delivery ratio exist, causing frequent sediment retaining or re-erosion and re-delivery of the retained sediments in a short period of time. Thus the delivery ratio will be 1. The sediment delivery ratio is closely related to the spatial distribution of rainfall and magnitude of rise and fall of peak flood and that of runoff depth in the drainage system. Delivery ratio of single event in a drainage system and changes of delivery capacity of silt-laden runoff in various classes of gullies can be expressed by transformation mechanism of shear force of a single rainstorm event with flood resulting from increase and decrease of peak flood per unit area.

关键词： delivery ratio interaction flood and geomorphology dynamic mechanism rainstorm flood

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Validity of the Bouchet's complementary relationship at 102.observatories across China

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Science China Earth sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2.ZHANG YongQiang3,LIU ChangMing1,2.1 institute of geographic sciences and natural resources Research,Chinese Academy of sciences,Beijing 100101,China 2.{2. laboratory of Water Cycle and Related Land Surface Processes,Chinese Academy of sciences,Beijing 100101,China 3 CSIRO Land and Water,PO Box 1666,Canberra ACT 2.01,Australia institute of geographic {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China key laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing 100101 China CSIRO La

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102.observatories at different elevations across ***,the relationship is appropriate at the low elevations(<1000 m).With the increase of elevation,vapor transfer power becomes much less than radiation energy budget because of lower vapor pressure deficit and stronger global solar *** a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation China

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Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 College of resources & environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

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Spatio-temporal carbon isotope variation during the Ediacaran period in South China and its impact on bio-evolution

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Science China Earth sciences 2009年第10期52卷 1520-1528页

作者： WANG XinQiang1 & SHI XiaoYing1,2.1 School of Earth Science and Mineral resources, China University of Geosciences, Beijing 100083, China 2.{2. key laboratory of Geological Processes and Mineral resources, Beijing 100083, China School of Earth Science and Mineral resources China University of Geosciences Beijing 100083 China state key {2. of Geological Processes and Mineral resources Beijing 100083 China

The Ediacaran period is characterized by the extremely negative carbon isotope anomalies and great biotic evolution in Earth history. At least four negative carbon isotope anomalies have been reported from this interval in South China so far. It is traditionally argued that the isotope variations can be used as a useful tool for global correlation of Ediacaran succession; however, more and more researches argued against this idea. We reviewed the previously published carbon isotope data in South China, and distributed the mean values of a certain time to the paleogeographic maps. The results show that the carbon isotope values (δ13C) vary greatly in different environments, but a clear tendency of becoming lighter from shallow platform to deep basin, with a maximum variation up to 1‰ Moreover, the important changes in Ediacaran biota, marked by the introducing of new taxa or ecologic groups, seemed to always postdate the negative anomalies but coincide with the positive shift. If the negative excursions represented the oxidation of a large dissolved organic carbon (DOC) reservoir in the ocean, the diverse Ediacaran organisms and the carbon isotope anomalies may suggest totally different environments: oxic and anoxic/euxinic. We also suggest that the elimination of euxinic state through precipitation of pyrites is one of the important environment factors in prompting the Ediacaran bio-evolution.

关键词： Ediacaran South China carbon isotope spatio-temporal variations bio-evolution

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Estimation methods of eco-environmental water requirements: Case study

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Science China Earth sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2. CUI Baoshan1 & LIU Jingling 1. School of environment, Beijing Normal University, Beijing 100875, China 2. state {2. Joint laboratory of environmental Simulation and Pollution Control, Beijing 100875, China 1. School of environment Beijing Normal University 100875 Beijing China 2. state key Joint {2. of environmental Simulation and Pollution Control 100875 Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2.10, 2.30, 2.50) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84×1010m3 to 1.02.1011m3, the suitable water requirement ranges from 6.45×1010m3 to 1.78×1011m3, the water shortage ranges from 9.1×109m3 to 2.16×1010m3 under the minimum water requirement, and it is from 3.07×1010m3 to 7.53×1010m3 under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2.10, 2.30, 2.50) are 4.49×1010m3?1.73×1011m3, 5.99×10m3?2.09×1011m3, and 7.44×1010m3?2.52.1011m3, respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

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