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61.
秦皇岛市地下水污染现状及评价 总被引:2,自引:0,他引:2
周淑敏 《河北工程大学学报(自然科学版)》1998,(1)
对秦皇岛市区地下水污染现状进行了分析,并采用污染起始值的计算,对该区地下水环境进行评价,提出了治理的建议 相似文献
62.
J. W. Magee 《International Journal of Thermophysics》1998,19(5):1381-1395
The p--T relationships have been measured for 1,1-difluoroethane (R152a) and 1,1,1-trifluoroethane (R143a) by an isochoric method with gravimetric determinations of the amount of substance. Temperatures ranged from 158 to 400 K for R152a and from 166 to 400 K for R143a, while pressures were up to 35 MPa. Measurements were conducted on compressed liquid samples. Determinations of saturated liquid densities were made by extrapolating each isochore to the vapor pressure, and determining the temperature and density at the intersection. Published p--T data are in good agreement with this study. For the p--T apparatus, the uncertainty of the temperature is ±0.03 K, and for pressure it is ±0.01% at p>3 MPa and ±0.05% at p<3 MPa. The principal source of uncertainty is the cell volume (28.5 cm3), which has a standard uncertainty of ±0.003 cm3. When all components of experimental uncertainty are considered, the expanded relative uncertainty (with a coverage factor k=2 and thus a two-standard deviation estimate) of the density measurements is estimated to be ±0.05%. 相似文献
63.
为研究华北平原地区河道渗漏损失,以“引黄济津”跨流域调水实测数据为依据,利用两岸地下水位变幅资料分析,提出河道水量损失线性模型,为华北平原区域调水过程中的水资源配置、调度和优化提供科学理论依据。 相似文献
64.
Recharge dams in Oman detain floods to recharge groundwater. The impact of sedimentation on recharge at Wadi Sahalanowt Recharge Dam, in Salalah, Oman, was evaluated using field data and numerical modelling. Analysis of the thickness of sediments after flood events shows that maximum depositions were at the same locations after each event, coinciding with the lowest positions in the wadi. Numerical modelling suggests that the current practice of periodic removal of sediments will restore the storage capacity of the reservoir, but that ploughing or raking of the underlying native sedimentary rocks could be required to significantly improve infiltration rates. 相似文献
65.
This paper analyzes the use of managed aquifer recharge (MAR) in community water supply in Finland and presents some international experiences for comparison. The framework of MAR consists of the natural environment and physical infrastructure, as well as socio-economic aspects, all of which are interrelated. Local conditions form the basis of an MAR system and to a large degree determine infiltration options and the most suitable methods. Finnish hydrogeology, climate and local conditions are highly comparable to those in Sweden but differ from those of other parts of Europe, Australia, the USA and Asia. This article provides a holistic view of MAR not only as a technical means of resource enhancement for water supply but also as an element interacting with the natural environment and society. 相似文献
66.
Ahmet Apaydin 《国际水》2013,38(3):314-327
The uneven distribution of water resources, a growing population, urbanization and global climate change require new approaches for groundwater management in Turkey. “Safe yield” should yield to broader concepts such as “sustainability”. Groundwater management needs to consider future needs of the people and all ecosystems in accordance with basin development models. Groundwater law needs to be expanded beyond quantity to address quality concerns. A new institutional framework should be established and groundwater regulation should reflect new approaches and ideas, in particular to address problems of application. 相似文献
67.
Abstract The main brackish groundwater resources in the State of Kuwait are the groundwater located in the Kuwait Group and the Dammam limestone aquifers. Most of the groundwater used in the State of Kuwait is for irrigation, some part of it is used for domestic purposes and for small scale industries. Since rainfall is seasonal and is less than the annual evaporation, the recharge from rainfall is negligible. Water levels in both the aquifers are highly affected by the pumping rate from each well. The groundwater is extracted heavily resulting in decline of water levels and the deterioration of groundwater quality though there is underflow from Saudi Arabia. Improvement of the groundwater management is essential for maintaining long-term productivity of the aquifers in the State of Kuwait. 相似文献
68.
Abstract Emerging intrastate transboundary issues focus on use of the Mahomet aquifer, which underlies about fifteen counties and many other political entities in east-central Illinois. This sand and gravel aquifer in the lower part of the buried Mahomet Bedrock Valley ranges between four and fourteen miles wide and from about 50 to 200 feet thick. Much of the region's rural population, several large communities, and many small towns obtain water from the Mahomet aquifer, as do industrial, agricultural, and commercial users. Increased development of the Mahomet aquifer to meet growing demands for water has caused conflicts over real or perceived adverse effects. One result has been the creation of fifteen resource protection zones and twelve water authorities. For groundwater supplies, resource protection zones help municipalities protect water-supply wells from potential adverse impacts. Many resource protection zones overlap one another, however, so this situation could lead to disputes over use of the resource. The reason that several of the twelve water authorities were organized was to meet a challenge perceived from a demand to be placed on the aquifer, in other words, a potential for conflict of use. Complicating the situation is that some of the water authorities overlap the resource protection zones. This could lead to disputes not only about water use, but also over which jurisdiction has the authority to settle a dispute. The Mahomet Aquifer Consortium was recently organized by concerned people representing diverse groundwater interests at the local level, including the private sector, professional organizations, and various governmental units. The consortium brings together representatives of some groups that typically did not communicate with each other in the past. The consortium may provide a forum through which emerging transboundary issues pertaining to use of the Mahomet aquifer can be addressed. Because the consortium is a voluntary organization that relies on consensus building, the success it may achieve in resolving future conflicts over groundwater use from the Mahomet aquifer remains to be seen. 相似文献
69.
70.
Unmetered electricity supply to agriculture has given rise to a unique and invidious water–energy–food nexus in India. Metering of agricultural consumers has been suggested as a way to break the nexus, but most states have not been able to meter farmers due to their opposition . The only exception is the state of West Bengal. Using primary data from a household survey conducted in 2010 when the metering process was still underway, this paper argues that farmers’ support for metering in West Bengal can be explained in terms of the economics of groundwater use and politics surrounding agriculture and groundwater in the state. 相似文献