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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. institute of geographic Science and natural resources, chinese academy of sciences, beijing 100101, china 3. Reconnaissance, Planning, Design and research institute, YRCC, Zhengzhou 450003, china beijing Normal University institute of geographic Science and natural resources Chinese Academy of Sciences Reconnaissance Planning Design and Research Institute YRCC

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

N_2O emissions from agricultural soils in the North china Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG yun\|she 1,2,3 , Dieter Scharffe 2, Manfred Domroes 3, QI yu chun 1, zhang Shen 1 (1. institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2O emissions from intensively agricultural soils of the North china Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2O emissions by a factor of 24.1—28.1, the calculated annual chemical N fertilizer\|transformed N\-2O\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2O emissions, which combined with the use of chemical N increased about 20% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2O N. Annual mean N 2O emission from our study area of fertilized soils was estimated to be 57.1 μgN 2O/(m 2·h). A weak correlation was also found between N 2O emissions and soil available nitrogen content NH + 4.

关键词： N_2O emissions the North china Plain agricultural soils chemical nitrogen organic manure

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 200032, 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 natural resources 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 30 to April 24, 2001 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.

Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, yu Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and zhang Renhua ( chinese academy of Meteorological Science, beijing 100081, china institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 200032, china) chinese academy of Meteorological Science Beijing 100081 China institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China Mathematics Department Ocean University of China Qingdao 266071 China Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china Plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

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

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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 resources and Hydropower Engineering, Wuhan University, Wuhan 430072, china institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing China College of Water resources and Hydropower Engineering Wuhan University 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.

Spatial-Temporal Changes of Soil Organic Carbon During Vegetation Recovery at Ziwuling, china

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Pedosphere 2005年第5期15卷 601-610页

作者： LI yu-yuan SHAO Ming-An ZHENG Ji-Yong zhang Xing-Chang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 （China）

To probe the processes and mechanisms of soil organic carbon (SOC) changes during forest recovery, a 150-yearchronosequence study on SOC was conducted for various vegetation succession stages at the Ziwuling area, in the centralpart of the Loess Plateau, china. Results showed that during the 150 years of local vegetation rehabilitation SOC increasedsignificantly (P 3,respectively. The decrease in SOC from 60 to 150 years of abandonment implied that the soil carbon pool was a sink forCO2 before the shrubland stage and became a source in the later period. This change resulted from the spatially variedcomposition and structure of the vegetation. Vegetation recovery had a maximum effect on the surface (0-20 cm) SOCpool. It. was concluded that vegetation recovery on the Loess Plateau could result in significantly increased sequestrationof atmospheric CO2 in soil and vegetation, which was ecologically important for mitigating the increase of atmosphericconcentration of CO2 and for ameliorating the local eco-environment.

关键词： soil organic carbon density spatial-temporal change vegetation recovery vegetation succession

Study on the changes of water cycle and its impacts in the source region of the Yellow River

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Science china(Technological sciences) 2004年第z1期47卷 142-151页

作者： zhang Shifeng1, JIA Shaofeng1, liu changming1, CAO Wenbing2, HAO Fanghua3, liu Jiuyu4 & YAN Huayun5 1. institute of geographic sciences and natural resources research, chinese academy of sciences, beijing 100101, china 2. china University of Geosciences, beijing 100083, china 3. beijing Normal University, beijing 100875, china 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 450003, china 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 810001, china institute of geographic sciences and natural resources research Chinese Academy of Sciences Beijing 100101 China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

Variation of fluxes of water vapor, sensible heat and carbon dioxide above winter wheat and maize canopies

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Journal of geographical sciences 2002年第3期12卷 295-300页

作者： zhang yongqiang, SHEN Yanjun, yu Qiang, liu changming,A. Kondoh, TANG Changyuan, SUN Hongyong, JIA Jinsheng(1. Inst. of geographic sciences and natural resources research, CAS, beijing 100101, china 2. Shijiazhang Inst. of Agricultural Modernization, CAS, Inst. of geographic sciences and natural resources research CAS Beijing China Shijiazhang Inst. of Agricultural Modernization CAS Shijiazhuang China Center for Environmental Remote Sensing Chiba Univ. Chiba Japan Graduate School of Science and Technology Chiba Univ. Chiba Japan

Surface energy fluxes were measured using Bowen-Ratio Energy Balance technique (BREB) and eddy correlation system at Luancheng of Hebei Province, on the North china Plain from 1999 to 2001. Average diurnal variation of surface energy fluxes and CO2 flux for maize showed the inverse “U” type. The average peak fluxes did not appear at noon, but after noon. The average peak CO2 flux was about 1.65 mg m-2 s-1. Crop water use efficiency (WUE) increased quickly in the morning, stabilized after 10:00 and decreased quickly after 15:00 with no evident peak value. The ratio of latent heat flux (λE) to net solar radiation (Rn) was always higher than 70% during winter wheat and maize seasons. The seasonal average ratio of sensible heat flux (H) divided byR n stayed at about 15% above the field surface; the seasonal average ratio of conductive heat flux (G) divided by Rn varied between 5% and 13%, and the averageG/R> n from the wheat canopy was evidently higher than that from the maize canopy. The evaporative fraction (EF) is correlated to the Bowen ratio in a reverse *** for winter wheat increased quickly during that revival stage, after the stage, it gradually stabilized to 1.0, and fluctuated around 1.0. EF for maize also fluctuated around 1.0 before the later grain filling stage, and decreased after that stage.

关键词： latent heat flux sensible heat flux carbon dioxide flux water use North china Plain

Nitrogen export by runoff and sedimentunder different types of land use inWest Tiaoxi catchment

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Journal of geographical sciences 2002年第4期12卷 443-450页

作者： LIANG Tao1, zhang Xiumei1, zhang Shen1, yu Xingxiu2, WANG Hao3(1. Inst. of geographic sciences and natural resources research, CAS, beijing 100101, china 2. Nanjing institute of Geography and Limnology, CAS, Nanjing 210008, china 3. institute of Reso Inst. of geographic sciences and natural resources research CAS Beijing China Nanjing institute of Geography and Limnology CAS Nanjing China institute of resources Science Beijing Normal University Beijing China

Five typical land covers in West Tiaoxi catchment of china, including mulberry garden, bamboo forest, pinery, vegetable plot and paddy field, were studied on nitrogen loss in artificial rainstorm runoff and sediment. Triple duplication experiments have been carried out under the artificial rain condition with an intensity of 2 ***?1 and lasting 32 minutes in 3 m2 field. Export of various species of nitrogen in runoff and sediment were investigated. The results show that nitrogen loss amount and rate are quite different among five kinds of land covers. The loss of total nitrogen in runoff of mulberry is the largest and that of paddy field is the smallest. Particle nitrogen accounts for 70–90% of total nitrogen in runoff of various kinds of land covers. Loss of dissolved nitrogen in pinery is much higher than in other kinds of land covers, which are similar among them. More detailed species of dissolved nitrogen show their respective features among various land covers. Total amounts of nitrogen loss from the top 10 cm layer of 5 kinds of soils are estimated as high as 4.66–9.40 g.m?2, of which nitrogen loss through sediment of runoff accounts for more than 90%. The rate of total nitrogen losses are ranged in 2.68–14.48 mg.m?***?1 in runoff, which is much lower than that of 100.01–172.67 mg.m?***?1 in sediment of runoff.

关键词： surface runoff nitrogen export artificial rainstorm land use