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Eco-environmental water requirement for wetlands in Huang-Huai-Hai Area, china

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Progress in natural Science:Materials International 2002年第11期 43-50页

作者： GUI Baoshan and YANG Zhifeng(1. Institute of environmental Sciences, beijing normal university State {2. Joint laboratory of environmental Simulation and Pollution Control, beijing 100875, china 2. Institute of Water Sciences, beijing normal university {2. laboratory for Water and Sediment Sciences, ministry of education, beijing 100875, china) Institute of environmental Sciences，beijing {2. university State key Joint laboratory of {2. Simulation and Pollution Control，beijing 100875，china Institute of environmental Sciences，beijing {2. university State key Joint laboratory of {2. Simulation and Pollution Control，beijing 100875，china Institute of Water Sciences Beijing Normal University key laboratory for Water and Sediment

Based on the related literature and the analysis of the relationship between wetland ecosystem and hydroperiod, the estimating and classifying methods of eco-environmental water requirement for wetlands are established. The data collected from Huang-Huai-Hai Area are from the electronic map (1:2.0000) of china National Topographical Database of 1997 and the historical statistics since the 1980s. The results indicate that the minimum eco-environmental water requirement for wetlands is 16.98 × 10 m and the optimal one is 38.38 × 109 m3 in the studied area. For the five wetland nature reserves covered in the area, the values are 1. 47 × 109 m3 and 3. 31 × 109 m3 respectively. The comparisons of the mentioned minimum water requirement with the status water use, which is 17.05 × 109 m3 for wetland ecosystem (1997 as the status year), suggest that the water use has not met the minimum eco-environmental water requirement in the Haihe and Huanghe Basins of the studied area. However, the status water use gu

关键词： eco-environmental water requirement wetlands Huang-Huai-Hai Area.

Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 College of Geographical Science, Chongqing normal university, Chongqing 400047,{2. 2.College of Resources and environmental Science, Chongqing university, Chongqing 400044,{2. 3 College of Resources Science & Technology, beijing normal university, beijing 100875,{2. College of Geographical Science Chongqing Normal University Chongqing 400047 China College of Resources and environmental Science Chongqing University Chongqing 400044 China College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern{2. in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern{2..

关键词：土地利用中国北方细胞自动机系统动力学

environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State key laboratory of Vegetation and {2. change,Institute of Botany,Chinese Academy of Sciences,beijing 100093, china 2.School of Geographic and Oceanographic Sciences,Nanjing university,Nanjing 2.0093,china 1. State key laboratory of Vegetation and {2. change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER

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Chinese Geographical Science 2001年第4期11卷 29-34页

作者： XIA Xing-hui1, CHEN Jing-sheng2. CAI Xu-yi3(1. Institute of environmental Sciences, beijing normal university / State {2. Joint laboratory of environmentalSimulation and Pollution Control, beijing 100875, P. R. china 2. Department of U Institute of environmental Sciences Beijing Normal University/ State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing P.R. China Department of Urban & environmental Science Peking University Beijing P. R. China Geography Department Graduate School of University of Science and Technique of China Beijing P. R. China

ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2.+, Mg2. and HCO3-concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na + Cl- SO2.4 have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43. 9% , 45.1%, 54.3%, 33.9%, 30.3% and 42. 7% of the variance of Ca2.+, Mg2. HC03-, Na+ Cl-, SO2.4, respectively, at Wuhan from 1962.to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data.

关键词： major ions spectrum characteristic of water quality water quality change the Changjiang River

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发生沟蚀(切沟)的地貌临界研究综述

山地学报 2005年第5期23卷 55-60页

作者：胡刚伍永秋北京师范大学沙漠与沙区资源研究所北京师范大学沙漠与沙区资源研究所北京100875 北京师范大学环境演变与自然灾害教育部重点实验室北京100875

沟蚀研究是土壤侵蚀研究的主要内容之一,地貌临界理论作为地貌学中的重要理论在沟蚀研究中得到了广泛的应用。主要从临界理论在沟蚀研究中的发展过程入手,介绍了国外现有沟蚀临界理论模型研究的主要成果,并指出现有模型的不足,在总结前... 详细信息

沟蚀研究是土壤侵蚀研究的主要内容之一,地貌临界理论作为地貌学中的重要理论在沟蚀研究中得到了广泛的应用。主要从临界理论在沟蚀研究中的发展过程入手,介绍了国外现有沟蚀临界理论模型研究的主要成果,并指出现有模型的不足,在总结前人工作的基础上,指出了现有临界模型今后的发展方向。

关键词：土壤侵蚀临界理论沟蚀切沟

Hazard Assessment of Urban Flood disaster and Safety Protection Strategy for Flood disaster Prevention and Reduction in{2.

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Hazard Assessment of Urban Flood Disaster and Safety Protect...

2.04安全科学与技术国际会议

作者： WANG Jingai1 2 3 WANG Jue1 2 & YE Tao1 3 (1 School of Geography beijing normal university beijing 100875 china) (2 key laboratory of Regional Geography of beijing normal university beijing normal university beijing 100875 china) (3key laboratory of environmental change and National disaster of ministry of education of china beijing normal university beijing 100875 china)

Based on disaster system theory and analysis of 70 cities in china whose population is over 600 thousand, a hazard assessment system has been established combining hazard-formative environments, hazar

关键词： urban flood disaster system integrated hazard index security of urban areas security protection strategy for flood prevention and reduction

Influence of Reaumuria Soongorica on Soil Properties and Soil Water Distribution at the Microscale in the Semiarid Loess Region of china

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Influence of Reaumuria Soongorica on Soil Properties and Soi...

国际农业工程大会

作者： Xiaoyan Li PhDchina Center of Desert Research beijing {2. university beijing 100875 chinaCollege of Resources Sciences and Technology beijing {2. university beijing 100875 chinaThe key Lab of Environment change and natural disaster ministry of education beijing 100875 china Lianyou Liu PhDchina Center of Desert Research beijing {2. university beijing 100875 chinaCollege of Resources Sciences and Technology beijing {2. university beijing 100875 chinaThe key Lab of Environment change and natural disaster ministry of education beijing 100875 china

＜正＞ The spatial distribution of Reaumuria Soongorica is characterized by a mosaic of patchy vegetation and bare area. However, little knowledge exists about the effects of these patterns on soil characteristics and water redistribution. The objectives of this paper are to study the effects of microscale distribution pattern of R. Soongorica on soil fertility, dust accumulation and soil water variation on loess slope. The results of this study indicated that the spatial

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Researches on the sand event frequency and the corresponding visibility in beijing District

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Researches on the sand event frequency and the corresponding...

第三届国际沙尘暴与降尘天气专题学术研讨会

作者： QIU Yu-jun~(1,2., ZOU Xue-yun~(1,2.,SUN Yong-liang~(1,2. (1.china Center of Desert Research, beijing normal university, {2., 100875,china 2.key laboratory of environmental change and natural disaster of the ministry of education of{12., beijing normal university, beijing 100875,china )

＜正＞ The negative effect of sand events to environment has been received increasing attention from home and abroad. It causes enormous visibility declination and severe air pollution. Based on the analysis of sand event days and the according visibility from 1971 to 2.00 in beijing meteorology station, it finds the minimum of mean visibility occurs around 2.00 Pm, and the maximum frequency of low visibility occurs around 8:00 Am, which may be related to pollution recharge and atmosphere motivation. The visibility of dust haze and dust storm is always in the range of 100 km, and, of sand storm, is 40 km. In all kinds of sand events, the normal deviation of visibility is in the opposite trend compared to its mean value. The normal deviation of visibility is smallest in dust haze, followed by dust storm and sand storm respectively. The high frequency for dust haze and dust storm events to occur is in the range of 90 days, The frequency of dust haze event within 60 days occupies 68.5% of the whole occurrence frequency of dust hazes;of dust storm, it occupies 88.9%. Dew to the low frequency of sand storms, averagely one time in one year, there are always long between the adjacent sand storms. The accumulation rate of interval occurrence days of adjacent dust hazes, dust storms, and sand storms respectively is 2.72., 0.82., and 13.97%.

关键词： sand event visibility interval occurrence days frequency

Risk Assessment of Aeolian Sand disaster on Lake in Sandy Area of Inner Mongolia

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Risk Assessment of Aeolian Sand Disaster on Lake in Sandy Ar...

首届风险分析与危机反应国际学术研讨会

作者： Yao-Jie Yue~(1,2. Jing-Ai Wang~(1,3,*) Xue-Yong Zou~4 Pei-Jun Shi~3 1 School of Geography, beijing normal university, 100875, {2., china 2.key laboratory of Regional Geography, beijing normal university, 100875, {2., china 3 key laboratory of {12. change and natural disaster of ministry of education of china, beijing normal university, 100875, {2., china 4 Desert Research Center of china, beijing normal university, 100875, {2., china

＜正＞It is very important to prevent lake from sand encroachment induced by aeolian sand disaster （ASD） for water resources conservation and the ecology-sound land use *** study investigated the structure and function system of ASD by systematic analysis,then index system and classification standard for comprehensive risk assessment were proposed.A case study was done in Inner Mongolia of northern china,and the results indicated that nearly 70% of the lakes receive the hazards of ASD and 45.5% lakes are seriously *** suggests that human disturbance responds to ASD significantly,and ways to reduce risk of ASD include regional land use optimization and engineering measures.

关键词： Aeolian sand disaster Lake Risk assessment Inner Mongolia