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991.
992.
The drainage basin of the acidic mining lake RL 111 was characterized by hydrogeological and geochemical models to assess its influence on a planned biotechnological remediation of the lake water and lake sediment. Ground, seepage and lake water, as well as the surrounding sediments, were examined to model the hydrodynamic processes and the geochemical developmentof the lake. The geochemical conditions seem to behave in a stable manner (steady state conditions). A reduction of the high sulphate andacid input has not been observed since the beginning of our investigations. The biotechnological remediation of the whole lake should consider a treatment of the dump sediments to improvethe quality of the inflowing groundwater, as well as to reduce erosion. 相似文献
993.
Abstract: Water industry experts have been arguing that the traditional techniques are not an accurate means of measuring water contamination. This is mainly because these techniques emphasize neither the stochastic nature of the water contamination process nor the precision and the accuracy of the tested methods used by environmental laboratories. In this work, we describe the development and application of prototype Dynamic Bayesian Networks (DBNs) that model ground‐water quality to determine the impact of chemical contaminants on ground‐water quality in the Salalah area, which is allocated to the south of Oman. We also present a new technique for data pre‐processing because it is needed for the treatment of ground‐water datasets that are used as the data source to learn the probabilities for dynamic decision models. Among more than 20 wells in area, only four wells were selected to be analyzed and the results show that we achieved an acceptable level of efficiency. 相似文献
994.
995.
鄂尔多斯白垩系环河含水岩组中的地球化学反向模拟 总被引:1,自引:0,他引:1
在了解鄂尔多斯盆地的地形、地势、地貌、新构造运动、岩石类型、岩性构造和其他特征的基础上,运用化学热力学原理、质量作用定律和质量守恒定律,用反向模拟的方法对白垩系环河组地下水进行了水-岩作用的地球化学模拟。对该区地下水的演化过程进行了定量的分析研究,揭示了其水化学场的形成机理,总结了矿物的溶解沉淀规律,为该区水文地质模型的建立、地下水资源的水质水量评价及其合理开发利用和科学管理提供了科学依据,可供该地区水土流失等地质灾害的预防和综合治理参考。 相似文献
996.
Pesticides can have a number of adverse impacts on crops, soil and water. In this paper, we focus on the physical and hydraulic
properties of soils controlling the leaching of pesticides into the shallow groundwater of the Rattaphum Catchment in Thailand.
Results from an analysis of soil physical properties, hydraulic conductivity, dye tracer and bromide tests show that the top
10–30 cm of soils in the three agro-ecosystems (vegetables, fruits and rubber) have a high clay and organic carbon content
and are relatively impermeable with very low hydraulic conductivity (15–40 cm/day). Most of the dye and bromide were retained
in the top clayey layer; the bromide forming a miniature bulge below 30 cm in two profiles which dissipated after 30 days,
while the pesticides were mainly confined to the top 10 cm. 相似文献
997.
C. B. England 《Journal of the American Water Resources Association》1973,9(3):590-597
Leaching of soils with water can be both beneficial and hazardous in the same instance, removing salts harmful to plants and contributing dissolved substances to groundwater. The leaching potential of a given soil is difficult to assess, even with complex instrumentation. This paper suggests that the final infiltration rates associated with the Hydrologic Soil Groups used by the USDA Soil Conservation Service in watershed planning may provide a useful guide in estimating quantities of leaching water moving through soil profiles. 相似文献
998.
垃圾填埋场渗滤液的防渗措施和地下水的污染防护 总被引:14,自引:0,他引:14
本文首先介绍了垃圾填埋场对其附近地下水体的潜在污染危害,着重介绍了为防止地下水体污染填埋场而采用的防渗措施,包括封场后的顶部覆盖层、中间夹层、底部集排系统以及底层和四周的衬层系统.然后介绍了由于防渗措施局部失效或其他原因(如破损、腐蚀等)引起渗滤液污染地下水以后可采用的防护方法(物理和生化技术),主要有隔离措施、地下曝气、反应墙或反应井、人工补给或抽水、水力截获、原位生物修复技术.最后简要介绍了对填埋场污染地下水这一问题的研究现状,并对这一方面的技术研究提出展望. 相似文献
999.
This case study details the difficulties of landscape management, highlighting the challenges inherent in managing natural resources when multiple agencies are involved, when the land users have no incentive for conservation, and when government agencies have too few resources for effective management. Pumping of groundwater from the aquifer of La Costa de Hermosillo in the state of Sonora, Mexico, began in 1945 and developed so quickly that by the late 1950s salinity intrusion from the Gulf of California was occurring in the wells. In the 1970s, the irrigatable land in La Costa peaked at 132,516 ha and the extracted volume of water from the aquifer peaked at around 1.14 billion cubic meters annually. By the 1980s, 105 wells of the total of 498 were contaminated with seawater and, therefore, identified for closure. At present La Costa de Hermosillo still represents 15% of the total harvested land, 16% of the total annual production, and 23% of the gross agricultural production of the state of Sonora. However,
there are approximately 80,000 ha of abandoned fields due to salt water intension, lack of water
and/or lack of credit available to individual farmers. This unstable situation resulted from the interplay of water management policies and practices, and farm-land policies and practices. While government agencies have been able to enforce better water use for agricultural production, there remains a significant area that requires restoration from its degraded state. For this piece of the ecosystem management puzzle, government agencies have thus far been unable to affect a solution. 相似文献
1000.