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线性规划在徐州地下水资源开发中的应用 总被引：1，自引：0，他引：1
本文从地下水系统的观点出发,对徐州地区中寒武统—中奥陶统碳酸盐岩地下水系统进行了分析。并应用线性规划的原理和方法对徐州市西郊四个水源地地下水进行了水文地质计算。在规定水位允许降深的约束条件下,求得至2000年,该区地下水最大开采量为14万米~3/天及各水源地相应取水量的最佳分配。文中采用特定条件图解法计算多边界、多主井抽水干扰影响的方法,具有通用意义。 相似文献
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(Department of Hydraulic Engineering Feng Chia University Taichung TAIWAN China Environment Section Agricultural Engineering Research Center Chungli TAIWAN China Shaohua Marko HSU Wei-Sheng YU) 《国际泥沙研究》1999,(2)
IINTRODUCTIONByutilizingthenatUralpowerofflow,hydraulicflushingisaneconomicaltechniquetoremovethedepositedsedimentineitherasettlingbasinorareservoir.Inmanyreservoirsaroundtheworld,hydraulicflushinghasbeenprovenasaneffectivemethodtosustainthereservoirstoragecapacity.Hydraulicflushingprocessesmayinvolveboththeprocessesofscouringpreviousdepositsandpassingincomingsediment-ladenflow,suchasgravitycurrent,throughareservoirtobereleased.Inthisarticle,onlytheformercaseisdiscussed.Thekeythinginthef… 相似文献
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以北京地铁某线X站为例,研究由于该站受施工工法(两端明挖中部暗挖)限制及交通和地下管线的影响,无场地实施封闭式管井井点降水,利用现有场地条件,在无法实施降水井封闭的区域周边布设降水井,进行干扰降水的方法对该区域地下水进行控制的问题。本文通过计算基坑涌水量,并运用等值线预测地下水降深的方法,对暗挖段地下水位降深进行计算与预测,结合预测结果并综合考虑周边环境和场地实际情况等因素,优化降水井布置,合理选择降水井泵量,通过实践检验达到了预期效果,既解决了由于无法实施封闭式管井井点区域的地下水控制问题,降低了工程风险,又节约了施工成本。 相似文献
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《Limnologica》2015
Water level fluctuations due to reservoir operations often cause spatial and temporal differences in water chemistry, which in turn can have considerable biological effects. Nonetheless, few studies have investigated the effects of fluctuating water levels on water quality and benthic macroinvertebrates in reservoirs in tropical countries, and none in the Philippine archipelago. We investigated the littoral zone of a Philippine reservoir subject to strong water level fluctuations and determined whether (i) water quality and macroinvertebrate community health is reduced when water levels are low, (ii) water quality declines with increasing water depth regardless of the overall water level, and (iii) water quality and community health decrease more strongly with water depth during low water level periods. Our study included five sites and four depths at each site, with three collections each during high and low water levels. Low water levels may have negatively affected four water quality and 10 biological metrics, whereas depth may have negatively affected two water quality and five biological metrics. Significant overall water levels by depth interactions were detected for four common taxa but none for water physicochemistry. Our findings show that tropical reservoirs may experience reduced water quality at low water levels, which can affect their biodiversity and potentially their ecological functioning. 相似文献
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数值法预报出抽水井处的水位是均衡域的平均值，它既不代表抽水井井壁水位，更不代表抽水井井筒水位。在数值法拟合、预报结果的基础上，若以抽水井处拟合水位与实抽水位之差作为由计算方法和井的作用共同产生的附加除深（△hf），以附加降深（△hf）与实际单井涌水量（Q实）之比作为附加降深系数（β）；多个抽水井时，可取其算术平均值作为平均附加降深系数（β），附加降深系数（β或β）与设计单井开采量（Q设）之积则是设计开采条件下抽水井的附加降深（△hf），再以抽水井处的预报水位（hj）减去该附加降深（△hf），便可得到抽水井井筒水位（hn）。 相似文献
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A. R. Awad S. A. Taqieddin A. S. Al-Homoud E. A. Barakat 《Environmental Geology》1997,30(3-4):198-208
This paper was mainly initiated to estimate some parameters of the quality and hydraulics of water in the vicinity of a proposed
dam site in Jordan. The assessment of the chemical character was carried out to examine the suitability of the groundwater
for domestic, municipal, industrial or irrigation use. Also, the anticipated problems associated with the quality of the reservoir
water were delineated. Pumping tests were conducted at some wells that were drilled within the dam site zone and drawdown-time
curves were constructed, by means of which the transmissivity and storage coefficients were assessed using two different methods.
Total dissolved solids and electrical conductance were also measured and the relationship between them established. In addition,
sodium ion concentrations at different piezometric tip elevations were measured in a number of wells that were previously
drilled inside the dam site zone. This data indicates that the water quality as expressed in terms of total dissolved solids,
electrical conductance, and sodium ion concentration limits do not comply with internationally recommended standards. The
usage of this water for usual domestic purposes is therefore not viable, while the utilization of this water for irrigation
purposes is very restricted.
Received: 1 September 1995 · Accepted: 2 April 1995 相似文献
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Lewis and Clark Lake is located on the main stream of the Missouri River. The reservoir is formed behind Gavins Point dam near Yankton, South Dakota, U.S.A. The Lewis and Clark Lake reach extends about 40 km from the Gavins Point dam. The reservoir delta has been growing since the closure of Gavins Point dam in 1955 and has resulted in a 21% reduction of storage within the maximum pool of the reservoir. Among several sediment management methods, drawdown flushing has been recommended as a possible management technique. The engineering viability of removing sediments deposited in the lake should be examined by numerical modeling before implementing a drawdown flushing. GSTARS4 was used for this study and calibrated by using measured data from 1975 to 1995. Channel cross-section changes and amount of flushed sediment were predicted with four hypothetical flow scenarios. The flushing efficiencies of all scenarios were estimated by comparing the ratios between water consumption and flushed sediment during flushing. 相似文献
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Governments are increasingly supporting initiatives to address plastic pollution, but efforts are largely opportunistic or driven by national socio-political priorities. There is an urgent need to move away from piecemeal single product instruments (e.g. single use plastic bag taxes or plastic straw bans) to deliver system-wide strategies that minimise the most pervasive sources of plastic pollution. Developing a common understanding of a jurisdiction’s plastic waste stream and the solutions available to decision-makers is vital to build consensus across stakeholders and to align on an evidence-based portfolio of priority instruments.This paper presents the Plastic Drawdown framework as a boundary-spanning tool to quickly create a coherent, relevant, and credible analysis and visualisation for stakeholders of plastic waste, leakage hotspots and minimisation opportunities. Using a new plastic waste modelling framework with a consultative structure, Plastic Drawdown explores plastic waste and leakage over a ten-year period and assesses impacts of policy instruments on this projection. Plastic Drawdown is adaptable to the data poor environment typical of many countries and designed as a rapid assessment tool to support the decision making of governments operating in a highly resource-constrained context.The Maldives is used as a case study to show the utility of the tool, where it highlighted strategies with the potential to reduce leakage of plastic waste into the marine environment by up to 85% by 2030. Plastic Drawdown built the case for phasing out single-use plastic waste across the Maldives and supported the Government’s decision to set ambitious targets, as announced at the United Nations General Assembly in 2019. 相似文献