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101.
Using the hydrogeological and socio-economic data derived from a European Commission research project on the measurement, monitoring and sustainability of the coastal environment, two optimization models have been applied to satisfy the future water resources needs of the coastal zone of Bardez in Goa, India. The number of tourists visiting Goa since the 1970s has risen considerably, and roughly a third of them go to Bardez taluka, prompting growth in the tourist-related infrastructure in the region. The optimization models are non-linear mixed integer models that have been solved using GAMS/DICOPT++ commercial software. Optimization models were used, firstly, to indicate the most suitable zones for building seaside resorts and wells to supply the tourist industry with an adequate amount of water, and secondly, to indicate the best location for wells to adequately supply pre-existing hotels. The models presented will help to define the optimal locations for the wells and the hydraulic infrastructures needed to satisfy demand at minimum cost, taking into account environmental constraints such as the risk of saline intrusion.
Résumé A l’aide de données hydrogéologiques et socio-économiques, dérivées d’un projet de recherche de la Commission Européenne sur l’étude, la surveillance et la durabilité de l’environnement c?tier, deux modèles d’optimisation ont été appliqués en vue de satisfaire les besoins futurs en ressources en eau de la zone c?tière de Bardez au Goa en Inde. Le nombre de touristes qui visitent le Goa depuis les années 70 a considérablement augmenté et environ un tiers d’entre eux se rend à Bardez taluka, ce qui encourage la croissance des infrastructures liées au tourisme dans la région. Les modèles d’optimisation sont des modèles non linéaires mixtes en nombres entiers qui ont été résolus en utilisant le logiciel commercial GAMS/DICOPT++. Les modèles d’optimisation ont été utilisés pour indiquer premièrement les zones les plus appropriées pour construire des stations balnéaires et des puits pour approvisionner en quantité d’eau suffisante l’industrie touristique, et deuxièmement pour indiquer la meilleure localisation de puits pour l’alimentation des h?tels préexistants. Les modèles présentés aideront à définir les localisations optimales des puits et des infrastructures hydrauliques nécessaires à la satisfaction de la demande à un co?t minimum, tout en prenant en compte les contraintes environnementales, tel que le risque d’intrusion saline.

Resumen Se han aplicado dos modelos de optimización en base a datos socio-económicos e hidrogeológicos derivados de un proyecto de investigación de la Comisión Europea sobre medición, monitoreo y sostenibilidad del ambiente costero para satisfacer las necesidades futuras de recursos hídricos de la zona costera de Bardez en Goa, India. El número de turistas que visita Goa desde la década de 1970′s ha subido considerablemente y cerca de un tercio de ellos van a Bardez taluka impulsando el crecimiento en la infraestructura turística de la región. Los modelos de optimización son modelos de números enteros mixtos no-lineales que se han resuelto usando el programa comercial GAMS/DICOPT++. Los modelos de optimización se usaron, primero para indicar las zonas más adecuadas para la construcción de centros de diversión en las márgenes del océano y pozos para abastecer la industria turística con una adecuada cantidad de agua, y segundo, para indicar la mejor localización de pozos para el abastecimiento de hoteles pre-existentes. Los modelos que se presentan ayudarán a definir las localizaciones óptimas para los pozos y las infraestructuras hidráulicas necesarias para satisfacer la demanda al mínimo costo, tomando en consideración restricciones ambientales tal como el riesgo de intrusión salina.
  相似文献   
102.
Broad relationships between weather and human health have long been recognized, and there is currently a large body of research examining the impacts of climate change on human health. Much of the literature in this area examines climate–health relationships at global or regional levels, incorporating mostly generalized responses of pathogens and vectors to broad changes in climate. Far less research has been done to understand the direct and indirect climate-mediated processes involved at finer scales. Thus, some studies simplify the role of climate and may over- or under-estimate the potential response, while others have begun to highlight the subtle and complex role for climate that is contingent on other relevant processes occurring in natural and social environments. These fundamental processes need to be understood to determine the effects of past, current and future climate variation and change on human health. We summarize the principal climate variables and climate-dependent processes that are believed to impact human health across a representative set of diseases, along with key uncertainties in these relationships.  相似文献   
103.
川滇震旦系灯影组葡萄石的沉积环境   总被引:1,自引:0,他引:1  
曹仁关 《云南地质》2002,21(2):208-213
川镇地区震旦系地层发育,其中,灯影组含葡萄石。本文记述云南宜良九乡震旦系剖面以及川滇地区震旦系葡萄石,并探讨其沉积环境。  相似文献   
104.
根据丘陵浅山地区8个测点低空风速实测资料进行风速廓线拟合,求得风速幂指数,将大气环境质量预测中的风速模式化,用来预测大气污染物的浓度分布。  相似文献   
105.
Previous research by our group (e.g., [Chem. Geol. 132 (1996) 25; Geochim. Cosmochim. Acta 64 (2000) 1363]) has shown that an aerobic Pseudomonas mendocina bacterium enhances Fe(hydr)oxide dissolution in order to obtain Fe under Fe-limited conditions. The P. mendocina is incapable of utilizing Fe as a terminal electron acceptor and requires several orders of magnitude lower Fe concentrations than do dissimilatory Fe reducing bacteria. The research reported here compared the effects of the P. mendocina on dissolution of well and poorly ordered Clay Minerals Society Source Clay kaolinites KGa-1b and KGa-2, respectively, under Fe-limited conditions. KGa-1b and KGa-2 contain 0.04 and 0.94 bulk wt.% Fe, respectively, and their surface Fe/Si atomic RATIOS=0.008 and 0.012. Following strong cleaning of the kaolinites in 5.8 M HCl at 85 °C, the surface Fe/Si atomic ratios decreased to 0.004 and 0.008, respectively. Both kaolinites also developed a Si-enriched surface precipitate upon strong cleaning.

Because the P. mendocina take up Fe, we could not measure Fe release from the kaolinite directly, but rather had to monitor it indirectly by comparing microbial populations sizes under Fe-limited growth conditions. We found that microbial growth on uncleaned, weakly cleaned, and strongly cleaned kaolinites increased with the amount of Fe readily available to organic ligands as estimated by dissolution in 0.001 M oxalate (pH 3). This suggests that it is the amount of readily accessible Fe that controls Fe acquisition and hence microbial growth. The trend is based on only a relatively small range of kaolinite Fe contents, and the research thus needs to be expanded to include kaolinites with a broader range of bulk and surface Fe concentrations.

Significant enhancement of Al release was observed in the presence of the bacteria, along with generally some enhancement of Si release. This enhancement of kaolinite dissolution could be related to an observed pH increase from 7–8 to 9 in the presence of the bacteria and/or to production of Al chelating agents. The P. mendocina produce a variety of organic exudates, including siderophores [Chem. Geol. 132 (1996) 25; Geomicrobiology (2001b)], and further studies into the effects of the siderophores on Al complexation and on kaolinite dissolution are ongoing.  相似文献   

106.
A process of urban regeneration of the former industrial dock area of east London by the London Docklands Development Corporation (LDDC) recognised the importance of geotechnical and geoenvironmental information. A systematic programme of data collection was implemented and stored in a series of bespoke computer database systems and cartographic registers. These allowed retrieval and manipulation of the data to provide rapid site assessments. The understanding of the natural setting of the area was enhanced as a consequence of the collation exercise. The data stored included geotechnical and environmental information on soil and groundwater. The hydrogeological regime was modelled by computer to determine the consequences of development on groundwater movement. In addition, a cartographic register of historic land use was developed. This gave instant detail on the potential for contamination of a site and became a fundamental tool in the UK planning process of the area. The information from the separate systems was finally combined into a geographic information system.  相似文献   
107.
青藏高原东北部古喀斯特过程与环境   总被引:6,自引:0,他引:6  
崔之久  陈怀录 《地理学报》1996,51(5):408-417,T001
本文介绍了青藏高原东北部地区的古喀斯特现象,并对相关沉积进行了化学成、粘土矿物的X-射线衍射以及石英砂表面结构等气候代用指标的分析。分析结果一致,指示了温暖湿润的亚热带气候条件。重结晶方解石的裂变径迹测年结果表明,该地区古喀斯特发育于中中新世。  相似文献   
108.
The relation of two well-known ancient carbonate deposits to hydrocarbon seepage was confirmed by this study. Archaea are found to be associated with the formation of Oxfordian seep carbonates from Beauvoisin and with a Miocene limestone from Marmorito ("tube-worm limestone"). Carbonates formed due to a mediation by archaea exhibit extremely positive or extremely negative δ13Ccarbonate values, respectively. Highly positive values (+15‰) reflect the use of 13C-enriched CO2 produced by methanogenesis. Low δ13C values of the Marmorito carbonates (–30‰) indicate the oxidation of seepage-derived hydrocarbons. Likewise, the δ13C content of specific tail-to-tail linked isoprenoids, biomarkers for archaea, was found to be strikingly depleted in these samples (as low as –115‰). The isotopic signatures corroborate that archaea were involved in the cycling of seepage-derived organic carbon at the ancient localities. Another Miocene limestone ("Marmorito limestone") shows a strong imprint of methanotrophic bacteria as indicated by δ13C values of carbonate as low as –40‰ and biomarker evidence. Epifluorescence microscopy and field-emission scanning electron microscopy revealed that bacterial biofilms were involved in carbonate aggregation. In addition to lucinid bivalves previously reported from both localities, we infer that sponges from Beauvoisin and tube worms from Marmorito depended on chemosynthesis as well. Low δ13C values of nodules related to sponge taphonomy (–27‰) indicate that sponges might have been linked to an enhanced hydrocarbon oxidation. Tube worm fossils from Marmorito closely resemble chemosynthetic pogonophoran tube worms from Recent cold seeps and are embedded in isotopically light carbonate (δ13C –30‰). Received: 13 October 1998 / Accepted: 5 February 1999  相似文献   
109.
21世纪世界的资源和环境   总被引:2,自引:0,他引:2  
20世纪世界人口从15亿增长到60亿.而经济成长更为快速,自1950年至今已增长4倍.目前世界人口每年增加8000余万人,至2050年将达到90亿,世界经济是否能持续发展以提升或维持现有的生活水准,值得研讨.资源的消长和环境的变迁是具有决定性的两大重要议题.  相似文献   
110.
效益-费用分析方法是环境影响评价中一种重要的方法。本文介绍了环境影响评价中的效益-费用分析方法的理论、程序及定量评价技术,概述了环境影响评价中效益-费用分析方法的理论及应用进展,并针对其存在问题,进行了探讨。  相似文献   
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