检索结果-南通市图书馆

Impacts of Soil-Water Conservation in Jialing River on Sedimentation of the three gorges Reservoir

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2006年第4期11卷 922-928页

作者： LEI Xiaozhang CAO Shuyou JIANG Xiaohua State Key Laboratory of Hydraulics and Mountain RiverEngineering Sichuan University Chengdu 610065 Sichuan China Soil Water Conservation Bureau of Sichuan Chengdu 610065Sichuan China

The Jialing River is one of the main tributaries of the Yangtze River. The average annual runoff accounts for 16 % and the sediment load 26% of the total at Yichang therefore it＇s one of the main contributors of sediment to the three gorges Reservoir. Ever since 1989, our country has implemented ＂Yangtze River soil and water conservation＂ project, Till the end of 1996, altogether 25.8 % of erosion area in Jialing River has been improved after large scale conservation has taken effect. The analysis and comparison between records taken before and after the implementation of soil and water conservation on runoff and sediment yield indicated that the sediment load soil erosion in Jialing river basin has been taken under control to some extent. Amount of annual runoff in main conservations have generally dropped by exponential function. Obvious result has been achieved in Jialing River, efficiency of sand reduction is about 10%-25%. Therefore, sediment to three gorges Reservoir is decreased accordingly, and it will be beneficial to take advantage of reser- voir＇s synthetic benefit.

关键词： Jialing River soil-water conservation run-off sedimentation three gorges

Environmental emigration stress of slope farmland in the three gorges area

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 2002年第4期12卷 420-426页

作者： WANG Liming, GUAN Qingfeng, YANG Yanfeng(Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) Inst. of Geographic Sciences and Natural Resources Research CAS 北京 100101

The project of ‘grain for green’, to restore woodland and grass by retreating from slope farmland, as a fundamental measure of eco-environmental rehabilitation, is being conducted in the reservoir area of the three gorges gradually. However, the de-farming of slope farmland will reduce the amount of farmland in de-farmed areas, especially in the areas with concentrated slope farmland, which would cause the problems of environmental emigration. The people who cannot regain enough farmland by relocating farmlands within village after de-farming and have to emigrate to other places are called environmental emigrants or ecological emigrants. In the research, a de-farming stress index model and an environmental emigration model are developed based on GRID data, and the potential amount of environmental emigration caused by de-farming of slope farmland in the reservoir area is simulated aided with GIS. The simulation indicates that the potential emigration amount caused by de-farming is quite large. When the de-farming stress index reaches 40%, the amount is as large as 890,000 people, which is equivalent to the emigrants caused by the submergence of the three gorges reservoir. So it should be considered as a big problem during the eco-environmental rehabilitation in this area. Some suggestions are raised to tackle the problem. Firstly, the emigration plan should be included in the de-farming plan. Secondly, some provinces, especially those located in the lower reaches of the Yangtze River, should accommodate part of the environmental emigrants.

关键词： environmental emigration slope farmland de-farming three gorges

ON SOME KEY SEDIMENTATION PROBLEMS OF three gorges PROJECT (TGP)

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 1989年 57-74页

作者： Lin Bingnan Dou Guoren Xie Jianheng Dai Dingzhong Chen Jisheng Tang Richang and Zhang Ren (Members of the Sedimentation Specialist Group. for the feasibility study of TGP.)

This article addresses the problems of maintaining a useful life for the reservoir. flood stages to be anticipated at Chongqing, sedimentation in its region of fluctuating backwater. deposition of sediment in the vici... 详细信息

关键词： Reservoir sedimentation Flood stage Mathematical model Yangtze three gorges Estu- ary Degradation. Flood control

STUDY OF three gorges RESERVOIR MANAGEMENT AND SUSTAINABLE RESERVOIR RESOURCES UTILIZATION PROGRAMS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

STUDY OF THREE GORGES RESERVOIR MANAGEMENT AND SUSTAINABLE R...

水电2006国际研讨会

作者： Liu Di Director of the Department of Reservoir Management General Office State Council three gorges Project Construction Commission No. Middle Beifengwo Road Haidian District Beijing City 100038

Reservoirs and dams are two inseparable parts of water and hydropower projects, and reservoir management is the key to safe dam operation. In October 2006, the three gorges Project will witness the completion of Phase III – reservoir filling and power generation at El 165 m, and the reservoir will be operated to provide a larger water surface during construction. How to enable scientificalized, systemized, institutionalized and standardized reservoir management, develop the project into a environment-friendly one deserving the name, and achieve sustainable development of the reservoir as guided by the scientific development concept, will be an important subject greatly concerned by all. In the context of the three gorges Project, the main part of the reservoir is the management of reservoir resources on the basis of the “Program of Sustainable and Multipurpose Utilization of three gorges Reservoir Resources” （referred to as the “Program” hereinafter）. As the three gorges Reservoir （referred to as the “TGR” hereinafter） management involves a lot, there is a high degree of complexity and a large number of uncertainties. Especially, there is nearly no scientific research to support the elevation and range of ecological defenses, the mode of fishery development, the management and protection of drawdown areas, and the directional classification of water functions in the reservoir region involved in the Program, without available experience in the respect of policy measures, management mechanisms, and rules and regulations. Furthermore, reservoir management and eco-environmental changes, including remedy measures, have never been studied thoroughly and systematically. It is necessary to study the Program in the respect of problems in reservoir operation management by mobilizing scientific research resources from all sources, especially in the aspect of the trend of eco-environmental evolution and the protective utilization of resources upon creation of the reservoir, to provide a basis for preparing a program of susta

关键词： three gorges reservoir management program study

Characteristics and mechanism of deep weathering of argillaceous limestones at Fengjie County,three gorges Region,Central China

在线全文

cnki会议

学校读者我要写书评

暂无评论

Characteristics and mechanism of deep weathering of argillac...

中国科学院地质与地球物理研究所2012年度（第12届）...

作者： Shengwen Qi Faquan Wu Zhong Qi Yue Chunling Liu Key Laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences Department of Civil Engineering University of Hong Kong Aero-Geophysical Survey and Remote Sensing Center The Ministry of Land and Resource China

The paper reports the ground conditions in the Sanmashan area where people were relocated as a consequence of the impoundment of the three gorges Reservoir. Examination of the geology indicates the strong calcareous rocks were not only highly fractured to considerable depths but were also decalcified in the near surface layers.A combination of the highly fractured state and decalcified nature of the material resulted in significant changes in the bedrock parameters between the northern and southern parts of the study area;the southern area having been affected by the deep down-cutting of the Yangtze River, release of stress and the development of three large landslides.

关键词： Landslide Weathering Deep seated gravitational slope deformation（DSGSD） Karstification three gorges

On evaluating the stability of the Baiyian ancient landslide in the three gorges Reservoir area,Yangtze River:a geological history analysis

在线全文

cnki会议

学校读者我要写书评

暂无评论

On evaluating the stability of the Baiyian ancient landslide...

中国科学院地质与地球物理研究所2008学术年会

作者： Souting Lee Key Laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of SciencesBeijingChina

Numerous landslides have occurred during the construction of the three gorges Reservoir of the Yangtze River.Although the underlying causal factor of these landslides was heavy rainfall,the construction process was the trigger of some of them.We report here a systematic study aimed at reconstructing the geological history of an ancient landslide and,based on our results,an evaluation of the role of the history on current landslide stability.Data from detailed field surveys and the studies on geological dating revealed that the Baiyian landslide was composed of five structural parts of different geological ages,such as a sliding belt,disturbed rocks,ancient colluvium,alluvium of the Yangtze River and slope wash.The succession of ancient climates,terraces and tectonic processes in the study area were examined from 300 ka ago.The evolutionary history of the Baiyian ancient landslide can be divided into five distinct stages:development,occurrence, deposition,collapse and disintegration.Some parts of the ancient landslide are currently prone to instability due to the combination effects of heavy rainfall and construction of the reservoir.

关键词： Ancient landslide Evolution Geology dating Geological history Stability three gorges

Exploration and Practice on Joint Regulation of Cascade Reservoirs for Xiluodu-Xiangjiaba-three gorges

在线全文

cnki会议

学校读者我要写书评

暂无评论

Exploration and Practice on Joint Regulation of Cascade Rese...

中国水利学会2016学术年会

作者： Wang Yuhua three gorges Cascade Dispatch and Communication Center

As the core projects of West Power to East,Xiluodu and Xiangjiaba reservoirs were built and operated successfully.These two reservoirs can enhance regulation and storage capacity of water resources in Yangtze River and also have an important significance for promoting flood resources utilization and optimal allocation of water resources.Moreover,the dispatching and operating of these two reservoirs could change the hydrological situations of the lower reach.This variation appears more obvious in the farther downstream,which brings a new opportunity for improving comprehensive benefits of three gorges.With the construction of water and rainfall telemetric network stations and reservoirs information sharing platform,China three gorges Corporation carries out active exploration and practice in the field of joint operation of the cascade hydropower stations in Yangtze River in recent years.All these measures which include joint operation of flood control,impounding water in advance and drawdown not only ensure the safety of the Yangtze River flood control,but also enhance the water use efficiency and clean energy production,play an important role in Yangtze River Golden Waterway,improve the ecological environment,promote the regional economic and social development as well as realize the harmony and unity of the economic benefits,social benefit and ecological benefits.

关键词： Cascade Reservoirs Joint Regulation three gorges

Apportioning above-and below-ground effects of moss biocrusts on soil detachment by overland flow in a subtropical climate

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Mountain Science 2021年第10期18卷 2646-2655页

作者： ZHANG Guan-hua YI Liang DING Wen-feng LEI Xu WANG Yi-ran SUN Bao-yang LI Jian-ming Soil and Water Conservation Department Changjiang River Scientific Research InstituteWuhan 430010China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan 430010China Central-Southern Safety&Environment Technology Institute Co. LtdWuhan 430071China

Biocrusts affect soil detachment through above-ground(top crust’s surface covering)and below-ground(sub-crust’s binding and bonding,B&B)effects,which might vary with biocrust development or coverage.However,these effects in humid climates are still unclear.This study was conducted to apportion and quantify the surface covering and B&B effects of moss biocrusts with five coverage levels(1%–20%,20%–40%,40%–60%,60%–80%,and 80%–100%)on soil detachment by overland flow in a subtropical humid climate.Two treatments with one being intact moss crusts and one removing the aboveground moss tissues were designed for each coverage level,and bare soil was used as the baseline.The results indicated that soil detachment capacity(Dc)and rill erodibility(Kr)decreased with biocrust coverage.After removing the above-ground moss tissues,the impeding effect of biocrusts on soil detachment weakened,but still increasing soil erosion resistance relative to bare soil.For intact crust,Dc was reduced by 50%–95%compared with bare soil,wherein 36%–55%and 14%–40%were attributed to the surface covering and B&B,respectively.The top crust contributed more than sub-crust to the soil detachment reduction,which were related to but not linear with biocrust coverage.When biocrust coverage reached mid-to-higher level(40%–100%),both top crust and sub-crust steadily contributed to soil detachment reduction with 60%and 40%,respectively.The findings advance a better understanding of the influencing mechanism of biocrusts on soil erosion in humid climates and highlight the importance of saving biocrusts as ecosystem functions.

关键词： Soil detachment Rill erodibility Effect apportionment Contribution rate three gorges

TEMPORAL AND SPATIAL DISTRIBUTION OF PHOSPHORUS IN THE XIANGXI RIVER

在线全文

学校读者我要写书评

暂无评论

水生生物学报 2006年第6期30卷 647-651页

作者： FU Chang-Ying 1,2, FANG Tao 1, DENG Nan-Sheng 2and YU Hai-Qiao 1,3 (1. Institute of Hydrobiology,the Chinese Academy of Sciences, Wuhan 430072,China 2. School of Environmental Sciences and Resources,Wuhan University, Wuhan 430079 3. School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070) Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 School of Environmental Sciences and Resources Wuhan University Wuhan 430079

The phosphorus in water and sediment collected at different time from the Xiangxi River were analyzed. The results indicated that the phosphorus pollution have significant relations to human activities (especially the phosphorus industry). The concentrations of total-phosphorus (TP), total dissolved phosphorus (TDP) and dissolved phosphorus (DP) in Dec.2004 were higher than those in Jul. 2005; the TP contents of sites 15 and 16 were much higher than others’, the TP content of the largest site 16 was 1946.29mg/kg in Dec. 2004 and 1756.11mg/kg in Jul. 2005, respectively, which was much higher than the average (1497.51mg/kg and 1369.38mg/kg, respectively). The TP content in the sediment of the Xiangxi River was from 1179.53mg/kg to 1851.20mg/kg. The TP contents of most sites except site 18, 19 and 20 were higher in Dec. 2004 than those in Jul. 2005. The aluminium-phosphorus (Al-P) content in the sediment was obviously higher in Jul. 2005 than that in Dec.2004, which indicated that the stability of Al-P has a significant relation to the change of season.

关键词： Phosphorus Sediment Adsorption and release Xiangxi River three gorges