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1.
三峡库区消落带不同垂直高程土壤重金属污染调查与评价   总被引:3,自引:0,他引:3  
为了揭示三峡库区消落区不同垂直高程土壤重金属污染状况,笔者通过对三峡库区消落带不同垂直高程(145~155、155~165、165~175 m)土壤样品的分析,结果表明三峡库区消落带土壤重金属污染以As、Cd为主,Hg、Pb污染程度相对轻微。从长寿到巴东,即从库区的上游到下游,重金属含量普遍呈下降趋势。综合评价结果表明:三峡库区9个区县消落带中,除涪陵的3个垂直高程土壤重金属超过背景值,处于轻度污染状态,其余区县的3个垂直高程土壤重金属处于警戒线以下,土壤未受污染。总体来说,长寿、涪陵地区消落带土壤受重金属污染,控制污染源是防止消落带土壤重金属含量增加的有效方法。  相似文献   

2.
Once the water level of the reservoir of the Three Gorges rises above 175 m, Yangtz River in Kaixian County will be changed into a lake-like reservoir which will be rare in the Three Gorges areas, and water pollution would be seriously deteriorated. In order to testify whether water quality meets the requirements of the function divisions, two-dimension water dynamics quality model and homogeneous-mixed water quality model are used to simulate polluted water disposal of Kaixian County before and after sewage purification. The analysis indicates that sewage disposal without any pretreatment will cause serious and continuous pollution; while sewage disposal after purificaiton up to standard, there are two kinds of results: in abundant and normal period , the water quality improves obviously, the water quality can meet the function of river area, but in dry seasons, the water quality improvement is not so effective, and still exceeds the control standard of the water function. To guarantee water quality of Xiaojiang River, it is proposed that, first, sewage treatment plant should run normally and continuously; second, other measures must be added to control sewage discharges in dry season.  相似文献   

3.
The typical pushed landslide deform becomes stronger when water fills in the Three Gorges reservoir. In order to better recognize the landslides deformation characteristics and prevent the disaster by the water change regulation, the paper takes an example of the features of geological conditions and deformation of Liangshuijing landslide in Yunyang which is the typical pushed landslide in the Three Gorges reservoir, and designs monitoring project. Through monitoring data including the surface displacement, ground fissure, deep displacement, ground water level, rainfall and macroscopic patrol, the variety law and relationship among monitoring data are obtained. The regularity of landslide deformation and its deformation velocity are concluded when the variation of the rainfall and water level change. Combined the variation of bands-stabilization coefficient, deformation laws of the pushed landslide by the rainfall or the reservoir water are obtained. The deformation caused by rainfall is large in the back landslide, while the deformation caused by hydrodynamic pressure is large in the front landslide. The higher the water level, the severelier of the influence. The deformation is largely influenced by hydrodynamic pressure when reservoir water declines sharply in the front landslide, and the deformation is the largest when rainfall and reservoir sharpe water decline happened simultaneously in the whole landslide. The law provides scientific basis for reduction and prevention disaster of the pushed landslide.  相似文献   

4.
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   

5.
City street construction in the Three Gorges Reservoir Area has a specific character. Some streets have characteristics adapted to changing water levels in the reservoir and to topography. In this paper, we analyze the development course and building char  相似文献   

6.
The one-dimensional flow model based on Saint-Venant equation is developed.Then,it is applied to calculate the holistic hydraulic characteristics in the natural condition of the Three Gorges Reservoir in Chongqing region,which is the 500 km-long mainstream beginning at Cuntan and ending at the boundary of Chongqing.Further,the model is applied to predict the hydraulic characteristics of the calculating zone at the time of the second stage of the dam construction(156 m storage level at the dam) and the completion of the project(175 m storage level at the dam).When the reservoir is operated at the storage level of 156m,the river-width of most corss-section increasing 2 times and the cross-section average velocity is reduced by 2/3 compared with these in the natural condition.When the reservoir is operated at the storage level of 175 m,the river-width of most cross-section increasing 2.5 times and the cross-section average velocity is reduced by 3/4 compared with these in the natural condition.The validating result indicates that the model properly reflectes the holistic hydraulic characteristics.This model is an effective tool for the assessment of the environmental impacts of the Three Gorges operated at the different storage level.  相似文献   

7.
With GC/MS Approach, PAHs in raw water and effluent of six water purification plants in Three Gorges Reservoir Area are analyzed quantificationally. Six species of PAHs such as acenaphthene, phenanthrene, anthracene, pyrene, fluoranthene and acenaphthylene are determined. Of which, fluoranthene is priority pollutant firstly listed by SEPA. The results show that there are several variety of PAHs in raw water and effluent in water purification plants of Three Gorges Reservoir Area, but on the whole, PAHs concentration level is low. The results also show that PAHs removal capacity of conventional water treatment techniques is poor.  相似文献   

8.
Yulin River is the major secondary stream of Three Gorges Reservoir Area. According to the requirement of "The Prevention Plan of Water Pollution in Three Gorges Reservoir Area and the Upper Areas (2001-2010)", the water environment pollution in Yulin River valley should be controlled. In this paper the reason of the water pollution is analyzed through investigation and evaluation on the present situation of Yulin River in North Chongqing area, and then a proposal on the prevention and cure measure of water pollution of Yulin River is presented.  相似文献   

9.
为了从环境教育的视角提出有针对性的建议,以便从源头控制生活污水的排放,选取100个典型样本,通过问卷调查方式,对库区山地村落村民生活污水排放态度的积极程度、生活污水知识的掌握程度、生活污水处理的自觉程度进行数据分析。结果表明,对生活污水排放态度的积极程度较差的是40岁以上群体、女性群体以及初中以下文化水平的群体;对生活污水知识的掌握程度较差的是40岁以上群体、男性群体以及初中以下文化水平的群体。各群体获取信息来源不同,是造成这种差异的主要原因。因此,应针对不同群体进行不同的环境教育,以提高当地村民的生活污水排放意识,有效保护当地及三峡水库的水环境安全。  相似文献   

10.
The effects of flooding and subsequent air-drying on NH_4~+ adsorption and the release of nitrogen of typical soils adsorbed ammonia in Three Gorges reservoir were studied in the laboratory.The influence of adsorption and release of soils in Three Gorges Reservoir on Aquatic Environment Quality was also studied.The results show that: 1) The adsorption ability is enhanced by flooding and subsequent air-drying.The capacity of the ammonia adsorption capacity was increased from 666 mg/kg to 833 mg/kg.2) Nitrogen,which has been adsorbed by sample soils in drawdrown area of Three Gorge area,is released under simulating flooding condition.The more the soil adsorbed,the more the nitrogen released.The ratio between aerobic condition and anaerobic condition is 1.2~1.4.3) The soils in drawdrown area of Three Gorge Reservoir can adsorb nitrogen from surface runoff,and during submersion periods the nitrogen is released.The risk of Eutrophication is increased in Three Gorges Reservoir.  相似文献   

11.
三峡库区次级河流污染现状与对策研究   总被引:1,自引:1,他引:1  
沉水植物金鱼藻和黑藻在治理三峡库区次级河流水体污染具有广阔前景,对保护三峡水库的水环境贡献很大,在库区水体中可以发挥强大的环境生态功能。本文通过分析三峡库区次级河流的环境问题,预测了金鱼藻和黑藻在库区的应用前景,即防止水体富营养化、有机物污染、重金属污染、抑制藻类生长,以及维持生物多样性、生态完整性和稳定性。  相似文献   

12.
方平  姚启伦  陈发波 《种子》2012,31(1):5-8
以10个来自三峡库区的玉米地方品种为材料,通过盆栽实验和设置低氮胁迫处理,研究低氮胁迫下玉米地方品种的苗期植株形态和生理效应.结果表明,低氮胁迫对玉米地方品种幼苗植株形态和生理有不同程度的不利影响,不同玉米地方品种的耐低氮特性存在明显差异.不同地方品种的同一植株性状和同一地方品种的不同植株性状的耐低氮胁迫指数存在差异.侧根数、叶面积、根体积和植株干重可作为玉米地方品种耐低氮种质筛选的形态指标,硝酸还原酶活性和丙二醛含量可作为耐低氮种质筛选的生理指标.此外,三峡库区玉米地方品种中有较丰富的耐低氮种质可供玉米育种利用.  相似文献   

13.
Jinshajiang River, which has a drainage area of 485,100 Km 2, average flux of 142.9 billion m 3, and soil conveyance of 247 million t/a, is the largest branch of Changjiang river. It is also the largest soil resource of the Three Gorges reservoir and upper reach of Changjiang River. To research the development and trend of Jinshajiang sediment not only has a relation to Jinshajiang water resource strategy, but also has important meaning to control the silt in Three Gorges reservoir and the Changjiang water resource development. The paper statistically analyses the flux and sediment conveyance of the Pingshan station, which is the primary hydrological station in the Jinshajiang River Drainage Area. Through several non-parameter statistical methods such as Spearman order correlativity check, Kendell order correlativity check, and linear regression check, the paper concludes that the sediment evolvement trend of Pingshan station is not distinct.  相似文献   

14.
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   

15.
The eutrophication of water body will destroy the balance of ecological environment.To determine the total nitrogen content in water body exactly,is one of the most important evaluating indicators that whether the water body has been polluted by eutrophication or not.After the foundation of the Three Gorges Reservoir,current velocity lowers and it may result in the eutrophication of water body.In terms of the Lambert-Beer Law,the authors adopt potassium sulpersulphate oxidation-ultraviolet spectrophotometry to determine the total nitrogen content in the Three Gorges Reservoir.By analyzing a variety of possible factors,they bring forward a method to determine the total nitrogen which can be used in lab and also have high performance.With this improved method,the authors determine the factual water samples of the Three Gorges Reservoir in the main urban area of Chongqing,and the result is that the total nitrogen content is(0.6~1.0) mg/L,less than the limiting value(2.0 mg/L) in national standard.So the water body of the Three Gorges Reservoir still eutrophication does not take place.So eutrophication does not take place in water body of the Three(Gorges) Reservior.  相似文献   

16.
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   

17.
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   

18.
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   

19.
三峡库区(重庆段)植被覆盖变化分析及评价   总被引:1,自引:0,他引:1  
摘要:为分析三峡库区(重庆段)植被及植被变化,利用2000—2015年MODIS 3级归一化植被指数16日合成产品MOD13A1,分析了长江沿线重庆段22区县植被指数的时空分布特征及变化趋势,结果表明:(1)在三峡库区蓄水后,长江沿线的植被表现为向好趋势,植被生长环境也有所改善,长江沿线东部地区,植被好转尤为明显。(2)距河道越远的区域,植被覆盖和植被环境越好。从行政区划角度看,东部区域植被生态环境最好,其次是中部区域、西部区域,主城区植被及生态环境较其余3个区域略显不足。植被好的区县(地区),平均高度值偏大。(3)三峡大坝完成175 m蓄水后较蓄水前(2000—2003年阶段),三峡库区175m蓄水后,远离河道区域,植被指数在春、秋、冬季节呈现增加趋势,夏季被指数呈减小趋势;近河道区域,植被指数在春季降低、秋季增加,夏、冬季有增有减。由于夏季全河道处于雨季,降雨偏多,河道会长期处于洪峰或高水位过程,河道被淹没的区域扩大;加之三峡蓄水后,夏秋季节河道上空薄云、碎云等云雾增加,即使夏半年三峡库区处于放水阶段,夏秋季节植被指数仍略有减小的趋势。冬半年河道基本不会出现高水位,河道内裸露土增加, 适于植被生长. 冬半年虽然处于蓄水阶段,但植被指数仍有增加趋势。  相似文献   

20.
紫色土中联苯菊酯残留对土著微生物的影响   总被引:1,自引:1,他引:0  
为了阐明紫色土农药残留的生态环境效应特征及土壤微生物响应机理,以三峡库区具代表性的紫色土为材料,通过玉米盆栽模拟试验和平板计数法,研究了残留态联苯菊酯对紫色土土著微生物数量的影响。结果表明,低浓度联苯菊酯对土著细菌和放线菌有显著的促生效应,依联苯菊酯浓度从低到高,土壤细菌和放线菌数量随时间逐次出现最高峰值:第6天,LB-L处理下的细菌和放线菌数分别达9.02×106 个/g和2.77×106 个/g,约为相应对照的9倍和3倍;第11天,LB-M的细菌数约为对照的77倍,达到5.19×107 个/g;第16天时,LB-H的细菌数为1.71×107 个/g,LB-M和LB-H处理下的放线菌数分别为4.04×106 个/g、4.35×106 个/g。其次,联苯菊酯残留对土著真菌有显著且迅速的抑制作用,即使在2.50 mg/kg残留水平下,真菌数量也会在施加联苯菊酯后第2天发生显著降低。再次,紫色土中3种土著微生物类群对残留态联苯菊酯均表现出一定的生态适应性,但表现有所不同:土著细菌的生态响应存在阈值,土著放线菌表现为较长时期内稳定的促生效应,土著真菌则表现为可恢复的抑制效应。试验表明,土壤微生物数量等生物因素可作为联苯菊酯对紫色土根际微生态影响的重要评价指标。  相似文献   

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