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1.
Using the revised BP-NN,this paper presented the neural network method for landslide stability analysis in the Three Gorges area.By choosing 30 typical landslides in this area as examples,the stability state estimated by the revised BP-NN method is highly consistent to that by conventional transfer coefficient method.And the method presented in this paper has following advantages:the input parameters are easily obtained and this method does not deeply rely on investigation quality and shear strength parameters of slips and is a quite simple one.The BP-NN method is a new measure to stability analysis of landslides in the Three Gorges area,which is especially suitable to the stability prediction of landslides before investigation.  相似文献   

2.
Such the geological hazards as landslide, rockfall, debris-flow and so on frequently occur in the Three Gorges Reservoir Area, so it is a very practical and immediate job to explore the mechanism caused the geological hazards and how to forecast and control the geological hazards. For this reason, this paper introduces the situation of the geological hazards occurred in the Three Gorges Reservoir Area and the major type and feature of the geological hazards occurred in Chongqing, and discusses the basic principle about the modern nonlinear science applied to the geological hazards and the creep-slip, stick-slip occurred on the joints of rock mass and the monitoring technology of the geological hazards.The basic thinking is put forward which can be applied the modern nonlinear science to the geological hazards occurred in the Three Gorges Reservoir Area.  相似文献   

3.
In this paper, the possible geological disasters in Three Gorges Reservoir Area are reviewed. Firstly, the types of geological disasters are classified and their influencing factors and growth characteristics are analyzed, then the damages, which have happened in this area up to now, are listed. On this basis, five aspects of dangers brought by geological disasters to society and economic environment are analyzed. Finally, a conclusion was drawn that the geological disasters in Three Gorges Reservoir Area have done some harms to this area and the situation becomes worse than before. So some reasonable measures should be taken quickly.  相似文献   

4.
作为控制食品安全的一种手段,很多国家和地区已经实施了HACCP体系,对羊肉生产过程中的各个环节可能存在的潜在危害进行了生物的、化学的、物理的分析,根据HACCP原理确定相应的关键控制点(CCP)和关键限值,并制定了相应的预防措施,建立了监控方法,将生产过程中的危害因素降低到最低程度,从而最大限度提高羊肉的食用安全性,旨在促进库区肉羊屠宰加工产业的发展。  相似文献   

5.
Suspended sediments play an important role in the transformation process of pollutants in rivers.The adsorption characteristic of suspended sediments in Three Gorges Reservoir Area to phosphate was studied in this paper.Based on the indoor adsorption balancing experiment and kinetic modeling experiment,the main factors for adsorption process of sediments(particle size of sediment,initial concentration etc.) were discussed.The major results of the experiment were as follows:(1) Three kinds of suspended sediments with different particle sizes were used for the study of adsorption characteristic with different sediment concentration.The amount of phosphate adsorption increased with the increase of the sediment concentration and sediment particle size.(2) With the help of Langmuir isotherm theory,the related parameters in kinetic model were estimated,the experiment results indicated that the adsorption isotherm of phosphate in Three Gorges Reservoir Area fitted with the fifth type of Langmuir adsorption isotherm,the maximum amount of phosphate adsorption would emerge when the phosphate concentration was relatively high,but it would move down when the phosphate concentration increased afterwards.(3) Phosphate adsorption increased with the increase of initial phosphate concentration,the average time for adsorption balance was 2-4 hours.  相似文献   

6.
There is a promising future for lateral aviation in the Three Gorges Reservoir Area of the Yangtze River because of the abundant natural and cultural tourism resources.The advantage of the lateral aviation is its low investment,convenience,speed,and wide service area.It is an important factor for the future development of tourism in cities in this area.This paper analyzes the realities and problems facing lateral aviation in this area and suggests some countermeasures and planning suggestions for lateral aviation development.  相似文献   

7.
针对三峡库区资源环境和农业生产现状及存在问题,探讨了农业资源持续高效利用的主要生产模式,即:种—养—加—销一体化模式、农林牧复合模式、农林复合模式、种—养立体农业模式和庭院高效生态农业模式等,并结合典型案例进行分析。此外,提出了实现农业资源持续高效利用的建议和对策。  相似文献   

8.
三峡库区农业非点源污染的思考   总被引:4,自引:0,他引:4  
三峡水库建成后,三峡库区生态系统服务价值将减少8852.90×104 ̄9708.35×104元。特殊生态环境有助于三峡库区农业非点源污染的发生,将对三峡水库水体安全造成极大威胁。建立不同土地利用类型下土壤养分流失模型是三峡库区农业非点源污染调控研究的核心,农业非点源污染防治的关键在于库区内土地利用结构的调整及拦截缓冲带的建立。  相似文献   

9.
A 1D hydrodynamic model on Pengxi Backwater Area (PBA) in the Three Gorges Reservoir during its preliminary operation period (2007 2008) is set up based on HEC RAS. In the large submerged area or water fluctuation zone, virtual levee is set up in the model between the conveyance channel and the storage area. The Manning’s n in PBA is calibrated and selected in the range of 0.27〖XC半字线.tif,JZ〗0.35. Calibrated model has good modeling results. Quasi Steady simulation approach is applied to calculate 1D hydrodynamic condition in the PBA during the study period. Analysis on the hydrodynamic condition in the PBA show that in the low water level operation stage, average velocity of upper reach in PBA will exceed 0.5 m/s, which is close to natural river. The Gaoyang Lake is formed as a relative independent and semi closure dam lake in the middle reach of PBA. Due to the enlarged cross section, the velocity at downstream of PBA is significantly decreased. In the high water level operation stage, no remarkable difference of velocity among cross sections in the PBA, indicating a significant hydrological characteristic of deep river based reservoir. The variation of reservoir capacity and hydraulic retention time in the PBA is 8.26×10 8〖XC半字线.tif,JZ〗2.51×10 8 m 3 and 157.0〖XC半字线.tif,JZ〗3.8 d respectively. The variation of reservoir capacity in PBA is impacted by the water level fluctuation more significantly. The hydraulic retention time in the PBA is impacted by both and river discharge dually. Frequency analysis show that 17.8% of hydraulic retention time data in the PBA is showed to be overflow reservoir type and 82.2% of that data showed to be transition type.  相似文献   

10.
三峡库区支流域澎溪河浮游动物的季节性变化与水质评价   总被引:1,自引:1,他引:0  
为研究三峡库区北岸最大支流澎溪河中浮游动物与水质状况的关系。本研究分别于2009年春季(3月)、夏季(7月)在澎溪河流域上游至下游5个河流断面进行采样,对水体中浮游动物的种类及数量进行监测,并应用Margalef丰富度指数(d)、Shannon-Wiener指数(H)和Pielou均匀度指数(J)对水体营养状况进行评价。研究发现:使用浮游动物评价水质状况得出的结论与营养水平评价结论存在较大差异,基于浮游动物种类及优势度评价得出的水质富营养化程度轻于基于营养盐的评价。  相似文献   

11.
The present study is to investigate the differences of Hg,Cr,Pb,Cd and Zn contents among water area ecology stystems of the three gorges Reservoir from water,dirt mud of the bottom and benthic fishes.The result show that content distribution of trace elements is:dirt mud of the bottom>benthic fishes>water;content distribution of trace elements in benthic fishes is:viscera>muscle>bone.The distribution factor of dirt mud of the bottom versus water,adsorption coefficient of benthic fishes versus dirt mud of the bottom and enrich coefficient of benthic fishes versus water is constant value in three Gorges Reservoir.Mercury is harm element to human in food chain.Besides,transform model of food chain in trace element are studied.  相似文献   

12.
综合考虑施肥管理方式和植物配置,本研究设置了常规施肥(CF)、常规施肥+生草覆盖(CF+GC)、常规施肥+生草覆盖+植物篱(CF+GC+PH)、水肥一体化(IWF)、水肥一体化+生草覆盖(IWF+GC)、水肥一体化+生草覆盖+植物篱(IWF+GC+PH)等管理措施,采用野外径流小区法,研究了不同管理措施对三峡库区柑橘园...  相似文献   

13.
为了解三峡库区花岗岩母质不同经济林模式的土壤养分状况,研究了各模式下土壤pH、有机质、全量养分和速效养分的特征,并利用主成分分析法对不同模式的土壤质量进行了综合评价。结果表明,除土壤pH外,经济林土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾等含量的变异较宽,为中等变异。随土壤层次的增加,各模式下土壤有机质、全氮、速效氮、速效磷和速效钾含量呈递减趋势,而全磷和全钾则存在不规律变化。土壤有机质、全氮和速效钾对经济林土壤质量的高低产生着主要作用,土壤养分综合排名表现为柑橘(精细管理)>柑橘(常规管理)>板栗林>茶园。因此,利用生物措施和精细化管理措施,可有效提高该区域经济林的土壤质量。  相似文献   

14.
The gases generated by anaerobic fermentation of organic solid wastes in Three Gorges Reservoir Area are CH_4,CO_2,H_2S,NH_3,H_2 and some micro-gases.Data analysis shows that in the cities and towns of Three Gorges Reservoir Area,4 380 thousand tones of garbage,3 800 thousand tones of faecal were generated each year.In landfill of the garbage in average of 290 millions kg of CH_4 was generated,also in average of 230 millions kg of CH_4 was generated from the faecal.CH_4 is a very important greenhouse gas;the proportion of its contribution to greenhouse effect is next to CO_2.Other gases only have small influence on the whole atmospheric environment.  相似文献   

15.
Complexity of mutual act and different sensation of different tourists are important factors influencing regional tourism resources evaluation. Fuzzy mathematic method can be used to up quantitative evaluation method on tourism resources evaluation. Taking Wushan Small Three Gorges as an example, the author carries out the evaluation of the tourism resources in the Three Gorges Reservoir. At the same time, the authors consider that five factors, such as improvement of the comunication of tourism resources, quickening the Steps of urbanization in reservior area, must be done well.  相似文献   

16.
After completion of Three Gorges Reservoir at Yangtze River, protecting and improving the ecological environment of this area is becoming increasingly important factor in comprehensive progress of the economy and society of Chongqing City. The industrial solid wastes are one of the crucial factors influencing the environment quality of Three Gorges Area and they are also the hot and difficult problems influencing the development of economy and society of Chongqing City. At this point, firstly, the discharge, present situation, prospect and development of treatment and utilization of industrial wastes in Chongqing are summarized. Secondly, the experience at home and abroad are analyzed. Then, the way and foreground for recycling the wastes with new technology are also discussed. Finally, countermeasure for treatment and utilization of industrial solid wastes after completion of Three Gorges Reservoir at Yangtze River is brought up. The study on treatment and utilization technology of industrial solid wastes will be beneficial not only to the protection of ecological environment of Three Gorges Area, but to the development of new Chongqing City as well. In a word, it will have great environmental, social and economic benefits.  相似文献   

17.
18.
The elements N and P are crucial to the water quality of Three Gorges Reservoir. After the present situation and characteristics of N and P pollutions analyzed and statistical method, flux method and modeling method adopted to estimate the quantity of N and P from upstream and reservoir area, the pollution loads of point and no-point pollution source, the conclusion that the main source of N and P pollutants are from both upstream of Reservoir and non-point pollution.  相似文献   

19.
Aiming at the problems emerging from the rapid construction of towns in Three Gorges Area,an incremental way of town designing is investigated, It is attempted to re-create a contemporary street and courtyard spaces, which evolved from the traditional local town spaces. As a conclusion, this paper puts forward some suggestion for further study and practice.  相似文献   

20.
The mechanical properties of slip soil play a key role in landslide stability. In order to study this control mechanism, multigroup experiments on the slip soil of a landslide were conducted in the Three Gorges reservoir in Zigui county involving consolidated quick direct shear test and consolidated drained direct shear test, through which the strain hardening property of this slip soil has been studiedas well as mechanism of landslide deformation resulting from the strain hardening slip soil. The results show that from plastic deformation to shear failure, the shear stress applied to this slip soil increases all the way. After repeated shearing, its shear strength increases, and the greater the normal stress, the more the shear strength increases, in which process the angle of internal friction contributes the most to its shear strength variation. Through the field investigation and numerical modeling, how the strain hardening slip soil affects the landslide stability was studied. In the process of sliding, the frictional strength of the strain hardening slip soil increases after being shearing, leading to the consumption of the landslide’s kinetic energy, following the phenomenon that a temporary steady state occurs after a short distance sliding.  相似文献   

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