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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.
周期性淹水对消落区水土环境的影响及控制对策   总被引：5，自引：0，他引：5  
三峡库区消落区生态脆弱,在水土交互作用下消落区土壤母岩风化成土进度加快、土壤侵蚀加剧、土壤氮磷等营养物质及重金属大量溶出,其中N、P、COD和重金属是主要的溶出因子,淹没的耕地是主要的污染源。成库初期消落区生态脆弱性增强、水土流失加剧、地质灾难增加、岸边污染加重,尤其在水流缓慢的库湾将会出现局部的富营养化现象;随着消落区稳定的库岸湿地生态系统的形成,水土耦合呈现正的环境效应。为了尽快构建健康的消落区生态系统,防止三峡库区消落区水土环境的退化,必须加强和发挥政府宏观调控职能、建立消落区土地保护区域、推广复合生态技术并做好库区污染防治与修复工作。  相似文献   

3.
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   

4.
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   

5.
Revitalization of waterfront-a precious resource of city has gradually become popular worldwide. Cities around the Three Gorges Reservoir grow and proper for the Yangtze River,thus waterfront in these cities has been long ignored or faced with "constructive destruction" with the city development. This paper divided urban waterfront public spaces around the Three Gorges into 3 kinds of spaces,namely point,line and surface,from the perspective of typology,and put forward strategies such as functional renovation,and improvement of spatial scale from the perspectives of land use and traffic,to enhance the vitality of waterfront public space.  相似文献   

6.
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   

7.
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   

8.
The relations between construction of Three Gorges Project and development of Wujiang River Basin are illustrated from three aspects. The importance of harmonious township development in Wujiang River Basin and Three Gorges Area is discussed and the strategies for harmonious development are proposed. Firstly, to promote the hydroelectric power development of the stream and accelerate the urbanization of Wujiang River Basin; next, establish rational urban system structure to realize the regional harmonious development within Three Gorges Area. Detailed proposition is given in this paper to establish the spatial relations between Wujiang River Basin and Three Gorges Area and further suggestion is put forward to perform research on urbanization and urban systems in these areas.  相似文献   

9.
The present status of water environment in three gorges area of Yangtze River is analyzed in this paper.The importance to enhance water environment protection and ecology environment protection in Three Gorges area of Yangtze River is also discussed in this paper. Some suggestions about water environment protection and ecology environment protection in Three Gorges of Yangtze River are also provided . Finally, the environment constructional targets to let clear water mirror on Three Gorges area of Yangtze River again are put forward.  相似文献   

10.
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   

11.
After the completion of the Three Gorges project,the navigation conditions of the reservoir region will be improved evidently,which has laid the foundation for straight run of the 10,000-ton-class fleet to Chongqing Port,and is the promotion of the development of shipping in Yangtze River.But according to the standard of the 10,000-ton-class fleet,there are still some reaches of the reservoir region can not meet the requirements of the waterway on smooth and safe navigation.Therefore,some regulation measures should be adopted to eliminate these obstructions.It is one of the important parts in the reservoir region waterway regulation work for the Fuling to Tongluo canyon reach blasting project.30 reef obstacle blocks of 14 reaches in this project were removed by blasting.Based on the analysis of obstruct features of various rocks,according to the standard of the 10,000-ton-class fleet,the design parameters and blasting regulation program were put forward,and the regulation effect is analyzed and forecasted.  相似文献   

12.
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   

13.
After the dam of the Three Gorges is built, the raising water will inevitably cause the revival of the part of ancient landslide and the generation of new landslide ,which will influence the town development and traffic safety in the Three Gorges Reservoir Area. In the light of the specific conditions of the Three Gorges Reservoir Area, this paper, taking Fengdu's MingShan landslide in Chongqing for an example, has considered ten typical calculative projects, offered the correspondent load systems acting on the sliding mass and put forward the analytical and calculative method to evaluate the stability of a landslide. The ten typical calculative projects include dry season(natural state), raining season (rainstorm or rain for a long period of time), dry season and water level (175m ) of the reservoir, raining season and water level (175 m) of the reservoir, dry season and earthquake, raining season and earthquake, dry season and water level (175 m ) of the reservoir and earthquake, raining season and water level (175 m) of the reservoir and earthquake, dry season and water level lowered from 175 m to 145 m, raining seasons and water level lowered from 175 m to 145 m, and so on.  相似文献   

14.
In view of the seriously-polluted water and broken eco-waterscapes in the Qiusuo Brook on campus of China Three Gorges University,this paper proposed the ecological restoration concept and mode of campus river according to field investigation and monitoring results,i.e. "reduce exogenous pollution—restore sediment microorganism—build intensified plant filter strip—build river water ecosystem and optimize landscapes—maintain ecological river course".In addition to introducing the design concept and principle of this mode,this paper specified the concrete projects such as sewage interception and water supplement,restoration of sediment microorganism,restoration of water plants,ecological restoration of embankment etc.,and also gave planar layouts and sketches of some projects,in order to provide references for the researches and practices of campus river ecological restoration in China Three Gorges University and other similar projects.  相似文献   

15.
Acid titration was performed to probe the acid buffering capacity of four types of typical soils from the Three Gorges Reservoir Region.The acid buffering capacity of soil was also applied to calculate the critical load for acid rain.The results indicated that the higher the pH value and CEC content of the soil,the greater the basic ions and acid buffering capacity of the soil would be.The critical load for acid rain was obviously different for four types of typical soils from the Three Gorges Reservoir Region.The order of the critical load for acid rain was red-brown purplish soil>red purplish soil>grey-brown purplish soil>yellow soil.The sensitivity of red-brown purplish soil to acid was much less than that of other three soils.  相似文献   

16.
充分运用遥感数据、数字高程模型和各种调查数据,以栅格为分析单元,利用层次分析法和GIS相结合的方法,实现了对三峡库区丰都县沿江地区土地生态安全状况的分析和评价,以期为三峡库区绿色生态屏障建设提供一定的指导。结果表明,研究区重警、中警、预警、较安全、安全状态的比例分别为0.15%、5.36%、41.85%、46.07%和6.57%,土地生态安全状态以较安全状态和预警状态为主。生态屏障区土地生态安全状况主要为重警、中警状态,该区域是沿江地区生态环境最为脆弱的区域。研究区长江南岸土地生态状况较好,而长江北岸土地生态状况主要以预警为主,土地生态功能退化较严重。通过对土地生态安全等级状况的分析,明确了区域土地生态安全格局和形成原因,为构建区域生态安全格局提供了有益参考。  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.
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   

19.
Some reasonable and suitable methods for factor calculation of the equation were chosen based on the American Universal Soil Loss equation,the characteristics of the Jialing River basin in P.R.China,and related research results.The soil erosion and loss in each hydrological unit of the basin were estimated using GIS.Employing the non-point source adsorbed nutrition load model,the loads of adsorbed nitrogen and phosphorus pollution were calculated and analyzed.The results show that the average sediment transportation module in the Jialing River Basin in recent years is 161.94 t/(km2a),and the loads of adsorbed nitrogen and phosphorus pollution are 29 620.8 t/a and 1 391.96 t/a,respectively,at the watershed outlet(Beibei hydrologic station).Adsorbed nitrogen and phosphorus pollution are serious in the Bailong River and Xihanshui basins.The descending order of land type with adsorbed nitrogen and phosphorus loss modulus is as follows: wild land,bush,turf,field,city and forest.  相似文献   

20.
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   

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