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Le barrage des trois Gorges (Chine)  [PDF]
Luc Merchez,Stéphane Puzin
Mappemonde , 1999,
Abstract: Le barrage des Trois Gorges, en construction sur le Yangzijiang, sera le plus grand barrage au monde. Le gigantisme du projet et sa médiatisation croissante en Occident permettent d'en saisir les enjeux environnementaux et humains. On analyse les grandes caractéristiques du projet et ses conséquences premières avant d'aborder le travail de recherche de l'équipe SIG de l'IGA de Grenoble qui vise à préparer la relocalisation de plus d'un million d'habitants, et à modéliser les impacts démographiques et sociaux.
Three Dimensional Seepage Analyses in Mollasadra Dam after Its Impoundments
GR Rakhshandehroo, M Vaghefi, ARH Zadeh
Journal of Applied Sciences and Environmental Management , 2011,
Abstract: Mollasadra dam is an earth fill dam with a clayey core and a height of 72 m from river bed, constructed on Kor River. pore water pressure in the dam was investigated following its construction and first and second impoundments. The dam was modeled by a finite element mesh. After the first and second dam impoundments, the overall trend in monitored pore water pressure was well modeled by the transient analysis. The result showed the six month time period between impoundments was long enough for the pore water pressure to reach equilibrium everywhere throughout the core, except where considerable initial constructioninduced pore water pressure was observed. High values of construction-induced pore water pressure at elevation 2050 m did not dissipate completely during the 6 month period of almost constant reservoir level (el. 2098.3 m) and the pore pressures were still at the transient state throughout the core. Therefore, it was concluded that pore pressures in the core of earth fill dams may not achieve steady state conditions even several months after the dam construction and impoundments.
Incremental Investment Value of Waterfowl Impoundments in the Upstate of South Carolina, USA  [cached]
R. Z. Clardy,W. M. Smathers, Jr.,T. J. Straka
Wildlife Biology in Practice , 2012,
Abstract: Financial incentives and economic factors play a role in expansion and survival of waterfowl in the Upstate of South Carolina. Satisfying a basic biological need, waterfowl impoundments are an effective way to ensure that migrating ducks have a food source, cover, and water on their journey south during the winter months (duck hunting season), but also year-round to ensure these birds return annually. Development of the region’s rural areas has resulted in a decrease in total area of flooded wetlands designated to waterfowl and a decline in waterfowl populations. At the same time, the willingness to pay to hunt ducks has escalated. South Carolinians drive across the United States in search for duck hunting when the same hunting experience could be created in their own backyard. The incremental value of creating a waterfowl impoundment was determined on five different properties in the Upstate of South Carolina (the study area). A discounted cost flow analysis approach was used that considered initial costs (a pond leveler, site preparation work, and blind building), recurring costs, and hunter revenue. The model also considered the opportunity cost of foregoing the harvest of planted crops on the land. Realistic examples are provided with corresponding net present values and geographic information system generated maps illustrate the layout of these impoundments. Waterfowl impoundments were found to produce significant financial return.
Chlorophyll Detection and Mapping of Shallow Water Impoundments Using Image Spectrometry  [PDF]
Francisco Artigas,Alex Marti,Norman Yao,Ildiko Pechmann
International Journal of Ecology , 2008, DOI: 10.1155/2008/146217
Abstract: There exists a common perception that chlorophyll a concentrations in tidal coastal waters are unsuitable to be captured by remote sensing techniques because of high water turbidity. In this study, we use band index measurements to separate active chlorophyll pigments from other constituents in the water. Published single- and multiband spectral indices are used to establish a relationship between algal chlorophyll concentration and reflectance data. We find an index which is suitable to map chlorophyll gradients in the impoundments, ditches, and associated waterways of the Hackensack Meadowlands (NJ, USA). The resulting images clearly depict the spatial distribution of plant pigments and their relationship with the biological conditions of the waters in the estuary. Since these biological conditions are often determined by land usage, the methods in this paper provide a simple tool to address water quality management issues in fragmented urban estuaries.
Characterization and assessment of potential environmental risk of tailings stored in seven impoundments in the Aries river basin, Western Romania
Erika Levei, Tiberiu Frentiu, Michaela Ponta, Claudiu Tanaselia, Gheorghe Borodi
Chemistry Central Journal , 2013, DOI: 10.1186/1752-153x-7-5
Abstract: Tailings were found to be highly contaminated with several hazardous/priority hazardous metals (As, Cu, Cd, Pb), and pose potential contamination risk for soil, sediments, surface and groundwater. Two out of the seven studied impoundments does not satisfy the criteria required for inert wastes, shows acid rock drainage potential and thus can contaminate the surface and groundwater. Three impoundments were found to be highly contaminated with As, Pb and Cd, two with As and other two with Cu. The tailings impoundments were grouped based on the enrichment factor, geoaccumulation index, contamination factor and contamination degree of 7 hazardous/priority hazardous metals (As, Cd, Cr, Cu, Ni, Pb, Zn) considered typical for the studied tailings. Principal component analysis showed that 47% of the elemental variability was attributable to alkaline silicate rocks, 31% to acidic S-containing minerals, 12% to carbonate minerals and 5% to biogenic elements. Leachability of metals and ions was ascribed in proportion of 61% to silicates, 11% to acidic minerals and 6% to the organic matter. A variability of 18% was attributed to leachability of biogenic elements (Na, K, Cl-, NO3-) with no potential environmental risk. Pattern recognition by agglomerative hierarchical clustering emphasized the grouping of impoundments in agreement with their contamination degree and acid rock drainage generation potential.Tailings stored in the studied impoundments were found to be contaminated with some hazardous/ priority hazardous metals, fluoride and sulphate and thus presents different contamination risk for the environment. A long term monitoring program of these tailings impoundments and the expansion of the ecologization measures in the area is required.Exploitation of mineral resources containing base and precious metals is one of the main activities that have contributed to the development of humanity. In the same time, mining has a negative reputation because of the large amounts of as
Destratification induced by bubble plumes as a means to reduce evaporation from open impoundments
M van Dijk, SJ van Vuuren
Water SA , 2009,
Abstract: The use of thermal mixing by means of compressed air appears to have important potential for evaporation suppression on deep reservoirs. Current methods used to reduce evaporation from open-water impoundments such as floating covers, modular covers, monolayers and shade structures have many disadvantages and negative impacts on the environment. These methods impact the natural/modified aquatic ecosystem established in the dam; alter aesthetic qualities; increase the risk of dam failure in times of flood; could potentially lead to an oxygen reduction in the water; and may compromise the natural water treatment functions and operations such as the reduction of harmful bacteria, exposure to sunlight (form of disinfection) and natural and mechanical aeration thereby increasing treatment costs. The methodology proposed in this paper to help reduce evaporation losses from open-water impoundments, which indirectly addresses problems of water shortage and the associated economic impacts, involves the destratification of the water body using a bubble plume operated with minimal energy input to reduce surface water temperatures, with, a subsequent reduction in evaporation. The literature, although limited, indicates that this proposed method has merit and requires further research to identify specific reservoirs (size, depth, usage) that could benefit from such a destratification system. Evaporation suppression of as high as 30 % was achieved in some case studies.

Xu Ping,Yang Tingqing,Xu Chunmin,Zhou Huoming,

岩石力学与工程学报 , 2002,
Abstract: The results of creep test in site for rock mass and discontinuity in shiplock area of the Three Gorges Project are introduced. Considering the effects of construction excavation and seepage pressure, the rheological analysis on the stability of shiplock slope is made during construction and running. The analysis results are validated by measured data in site.
三峡船闸高边坡岩体的细观损伤 及长期稳定性研究

Sun Jun,Ling Jianming,
孙 钧

岩石力学与工程学报 , 1997,
Abstract: With a scanning electron microscope, the authors carried out a series of tests on the amphibole plagioclase granite, taken from the weakly weathered zone of the high slope of the Three Gorges shiplocks, and investigated the meso time dependent damage behaviour of the rock. Then, on the basis of the meso damage theory for brittle elastic rock mass, which was established by the authors, this paper analysed the influences of meso time dependent damage of the rock on the stability of the shiplocks slope. It is shown that the long term stability of the slope will be very good if only from the point of view of the creep rupture time of the rock material.
A Review of Research on Tourism Geography of The Three Gorges  [PDF]
ZHANG Shu-lin,GE Xiao-tao
Journal of Chongqing Normal University , 2010,
Abstract: The Study of Yangtze River Three Gorges Tourism Geography have great significance for the Yangtze River Three Gorges tourism development.With the completion of the Three Gorges Project and the development of the tourism, the research is gradually increasing about the Yangtze River Three Goreges tourism geography.In a comprehensive analysis of nearly a decade on the basis of relevant literature,in this paper,used by geography and tourism science-related research methods.This article focuses on several major reviews and studies of the hot areas of development of tourism resources,tourism activities and geographical environment,the improvement of tourism traffic,joint development of regional tourism,tourism development and its regional impact,tourism industry geography and so on. Through the last decade the analysis of relevant literature and collation,can be drawn Study of the Yangtze River Three Gorges Tourism Geography plays an important role for the development of domestic Tourism Geography,but at present there are still some problems,example lack of innovation in research methods, theoretical support for small, pairs of case studies have not enough attention and so on.Accordingly,Should Improve discipline, and widen the scope of the study; strengthen theoretical innovation; to build research methods system; Transformation of thinking, Expansion of research vision and so on. Hope this thesis can helps to provide reference to in-depth study about Geography Tourism of the Three Gorges.
Comparative analyses of the vascular flora of the P inja river gorges in Serbia and Macedonia  [PDF]
Zlatkovi? B.,Nikoli? L.,Ran?elovi? V.,Ran?elovi? N.
Archives of Biological Sciences , 2011, DOI: 10.2298/abs1104157z
Abstract: The study’s aim is the comparative chorologic and ecological analysis of the vascular flora of the two gorges of the P inja River in Serbia and Macedonia which are 27 km apart. In the two gorges 1564 taxa have been recorded, 1057 being in the upper gorge in Serbia and 1174 in the lower gorge in Macedonia. Common to both gorges are 666 taxa. Chorological spectra show that in both gorges the most abundant are Mediterranean-submediterranean plants, 32.85% being in the upper and 43.97% in the lower gorge. Differences in the studied vegetation result from a diverse participation of other floristic elements such as Central European ones that are more abundant in the upper gorge (17.05%) than in the lower gorge (10.86 %). The life-form spectrum reveals that the flora in both gorges is hemicryptophyte-therophyte in character. Both gorges belong to an enclave of a Mediterranean-submediterranean region, i.e. to its submediterranean Macedonian- Thracian province.
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