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Younger groundwater found in some Omani aquifers is a result of recent recharge from cyclonic and storm events [Weyhenmeyer et al. (Science 287:842–845, 2000); Young et al. (J Appl Geophys 57:43–61, 2004)]. The analysis of the meteorological data in Oman indicates an anomalous rainfall on a decadal interval whereas cyclones frequency is expected to increase due to global climatic changes. The cyclone Gonu has severely struck the eastern Omani coasts in 2007 resulting in devastating floods. Huge volume of water (3,672 mm3) spread over the coastal plain calling for an assessment of potential groundwater recharge subsequent to this event. The present study evaluates groundwater recharge with respect to Gonu 2007 to assess the potential of recharge induced by such cyclones in the arid zones. The hydrographs of several piezometers sited along the coastal plain in Muscat Province have been studied and variation in water table rise has been analyzed. Significant water table rise is indicated for areas with geological and structural settings favoring rapid infiltration of water yielding considerable groundwater mound, whereas piezometers located in less favorable zones show minimum rise of water table. However, soon after the floods the aquifer hydrodynamics has readjusted to attain equilibrium and the groundwater mound dissipated. The cumulative rise of the water table on an areal extent does not exceed a few centimeters indicating lesser volume of recharge. Comparatively, recharge from frequent precipitation along favorable zones produces more significant recharge compared with cyclonic events where surface water residence time is shorter to allow for efficient infiltration.  相似文献   
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The Krishni–Yamuna interstream area is a micro-watershed in the Central Ganga Plain and a highly fertile track of Western Uttar Pradesh. The Sugarcane and wheat are the major crops of the area. Aquifers of Quaternary age form the major source of Irrigation and municipal water supplies. A detailed hydrogeological investigation was carried out in the study area with an objective to assess aquifer framework, groundwater quality and its resource potential. The hydrogeological cross section reveals occurrence of alternate layers of clay and sand. Aquifer broadly behaves as a single bodied aquifer down to the depth of 100 m bgl (metre below ground level) as the clay layers laterally pinch out. The depth to water in the area varies between 5 and 16.5 m bgl. The general groundwater flow direction is from NE to SW with few local variations. An attempt has been made to evaluate groundwater resources of the area. The water budget method focuses on the various components contributing to groundwater flow and groundwater storage changes. Changes in ground water storage can be attributed to rainfall recharge, irrigation return flow and ground water inflow to the basin minus baseflow (ground water discharge to streams or springs), evapotranspiration from ground water, pumping and ground water outflow from the basin. The recharge is obtained in the study area using Water table fluctuation and Tritium methods. The results of water balance study show that the total recharge in to the interstream region is of the order of 185.25 million m3 and discharge from the study area is of the order of 203.24 million m3, leaving a deficit balance of −17.99 million m3. Therefore, the present status of groundwater development in the present study area has acquired the declining trend. Thus, the hydrogeological analysis and water balance studies shows that the groundwater development has attained a critical state in the region.  相似文献   
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Atlantic Bluefin Tuna is an important but not well managed fishery in the Mediterranean Sea. In this paper, management system is evaluated with information on stock status, resource rent, and total employment. The non-restrictive implementation of International Commission for the Conservation of Atlantic Tunas (ICCAT) policies is found to be the institutional reason for its management failure, while the common-property and shared stock nature of this fishery is the fundamental reason. To address these major issues, policy schemes are proposed to help sustainably manage this valuable resource in the Mediterranean Sea.  相似文献   
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We present a contaminant treatment system (CTS) package for MODFLOW 6 that facilitates the simulation of pump-and-treat systems for groundwater remediation. Using the “nonintrusive” MODFLOW 6 application programming interface (API) capability, the CTS package can balance flows between extraction and injection wells within the outer flow solution loop and applies blended concentration/mass treatment efficiency within the outer transport solution loop. The former can be important when the requested extraction rate cannot be satisfied by the current simulated groundwater system conditions, while the latter can be important for simulating incomplete/imperfect treatment schemes. Furthermore, the CTS package allows users to temporally vary all aspects of a simulated CTS system, including the configuration and location of injection and extraction wells, and the CTS efficiency. This flexibility combined with the API-based implementation provide a generic and general CTS package that can be applied across the wide range of MODFLOW 6 simulation options and that evolves in step with MODFLOW 6 code modifications and advancements without needing to update the CTS package itself.  相似文献   
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As the world’s largest importer of marine ornamental species for the aquaria, curio, home décor, and jewelry industries, the United States has an opportunity to leverage its considerable market power to promote more sustainable trade and reduce the effects of ornamental trade stress on coral reefs worldwide. Evidence indicates that collection of some coral reef animals for these trades has caused virtual elimination of local populations, major changes in age structure, and promotion of collection practices that destroy reef habitats. Management and enforcement of collection activities in major source countries such as Indonesia and the Philippines remain weak. Strengthening US trade laws and enforcement capabilities combined with increasing consumer and industry demand for responsible conservation can create strong incentives for improving management in source countries. This is particularly important in light of the March 2010 failure of the parties to the Convention on International Trade in Endangered Species (CITES) to take action on key groups of corals.  相似文献   
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This paper used the Lesotho Highlands Water Project (LHWP) that transfers water from the Orange River Basin in Lesotho to the Vaal River Basin in South Africa as a case study to show how environmental sustainability aspects can be integrated into economic development planning. Using the Ecological Social Accounting Matrix (ESAM) for Lesotho that integrates ecological implications of the LHWP with economic benefits of the project, the paper analysed the impact of lost ecological services downstream the LHWP dams in Lesotho on the well-being of households directly affected by the project (riparians) and the general economy of the country. The results revealed that despite significant economic benefits, the project has unintended impacts on ecological resources and services with resultant deleterious well-being implications for riparians. The results from the ESAM analysis indicated that not only the income of riparians is likely to suffer, but also that of other households and social groups, as well as the general economy of Lesotho. While results of the ESAM analysis did not indicate large income impacts on the economy at large, they were significant for riparians. The importance of integrating ecological consequences into impact assessment of IBWT before such transfers can be implemented to ensure sustainable development and considering economy-wide impacts associated with IBWT was proven necessary for a holistic impact assessment of IBWT.  相似文献   
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The Lower Miocene Euphrates and Jeribe formations are considered as the main targets of the Tertiary petroleum system in the western part of the Zagros Basin. The formations consist of carbonates with some evaporate intercalations of the Dhiban Formation. This study utilized data from a field investigation including newly described outcrop sections and newly discovered productive oil fields within the Kirkuk embayment zone of the Zagros fold and thrust belt such as Sarqala and Kurdamir wells. This work is the first to show a stratigraphic correlation and paleoenvironmental interpretation by investigating both well data and new outcrop data. Three depositional environments were identified, (1) an inner and outer ramp belts environment, (2) shoal environment, and (3) restricted lagoon environment. Within these 3 environments, 12 microfacies were identified, based on the distribution of fauna mainly benthonic foraminifera, rock textures, and sedimentary structures. The inferred shallow water depths and variable salinities in both the Euphrates Formation and Jeribe Formation carbonates are consistent with deposition on the inner ramp (restricted lagoon and shoal) environments. Those found in the Euphrates Formation constrained the depositional environment to the restricted lagoon and shoal environment, while the microfacies in the Jeribe Formation provided evidence for an inner ramp and middle to outer ramp belt environments. This study represents the first detailed research that focuses on the stratigraphic correlation and changes in carbonate facies with the main aim to provide a wider understanding of stratigraphy of these carbonate reservoirs throughout the northern part of Iraq.  相似文献   
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