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961.
膨胀土(岩)渠道破坏机理和处理技术研究 总被引:2,自引:1,他引:1
通过多种研究手段综合研究了南水北调中线工程总干渠膨胀土(岩)渠坡破坏机理,提出了适合的膨胀土(岩)渠坡稳定性分析方法;针对性地研究了膨胀土(岩)渠道的处理措施,主要措施在试验渠段进行了现场验证比较,提出了经济可行的处理方案。研究成果不仅为南水北调中线工程膨胀土(岩)渠坡处理提出更为可靠合理的解决方案,其研究思路和成果也可供类似研究和工程应用参考。 相似文献
962.
博弈论模型在解决水资源管理中利益冲突的运用 总被引:2,自引:1,他引:1
本文运用非合作与合作博弈的方法,对南水北调中线工程水资源管理中的有关利益冲突进行模拟和分析。其中,以统计学和经济计量学的回归分析法构建博弈各方的效益函数,以经济价值评估法折算水资源的价值和水污染的损失,用成本效益分析法比较不同战略下的博弈结果。模拟结果显示,若以北京为博弈的甲方,则非合作结果使局中的乙方、丙方和丁方分别获得0.15~0.32亿元、0.59~0.364亿元和0.08~0.29亿元的利益,但整体却遭受662.01~1218.33亿元的损失,而合作的结果恰恰相反。因此,如果能够把合作所带来的部分净收益从赢利方转向损失方,以补足损失方的损失,博弈各方均能受益。此模拟方法及结果不仅有利于博弈各方,而且也为水资源管理部门提供决策支持。 相似文献
963.
Abdrabbo A. Abou Kheira 《Water Resources Management》2009,23(11):2317-2342
The Egyptian Ministry of Water Resources and Irrigation (MWRI) has expressed concern about the current high cost of the Irrigation Improvement Project (IIP) implemented in the “old lands” of the lower reaches of the Nile River. Because the IIP is financed through fees paid by the direct beneficiaries of the project, i.e., irrigation water users, these same Egyptian agricultural producers are especially sensitive to the higher than expected costs that the project has incurred to date. The objective of the current study is to evaluate whether this cost reduction is associated with any deficiency in irrigation performance. This Monitoring and Evaluation (M&;E) study aims to answer questions such as: Does reducing pump capacity and increased pump operation affect the farmers negatively? And, does the use of electricity instead of diesel fuel affect the farmers positively? Six indicators were used to compare new design criteria in the W10 and the IIP1 irrigation system designs, water savings, irrigation cost, irrigation time, night irrigation, and land savings. The W10 project design achieved the minimum actual operating cost per unit of area and per unit of water compared to the IIP1 project design on both Meet Yazied and El-Mesk Canals. The total cost per unit of area in the W10 project design is lower than IIP1 by 19.33% and 24.92% on the Meet Yazied and El-Mesk Canals, respectively. The total cost per unit of water in the W10 design is also lower than IIP1 on the Meet Yazied and El-Mesk Canals. Average irrigation time for rice and cotton crops cultivated in the W10 area are higher than average irrigation time for these crops cultivated in the IIP1 area for all locations on the Mesqa (head, middle and tail), because of increased pump operation in the W10 area (16 to 20 h d???1). The number of irrigation events at the head of the Sefsafa Canal in the W10 area is higher than on the Meet Yazied and El-Mesk Canals in the IIP1 areas because of the increased pump operation in the W10 area. 相似文献
964.
The pressures of human population and patterns of development frequently jeopardize the integrity of river systems worldwide.
An integrated approach to water resources management is essential, particularly in developing countries. This study presents
the results of the water resources optimization conducted for the Lower Litani River Basin in Lebanon. The overall aim of
the project is to develop, test, and critically evaluate an innovative approach to water resources management in the Mediterranean
region. The method explores the ways in which multiple environmental, economic, and social benefits can be achieved through
integrated management of water resources. The Water Resources Model was utilized to assess the efficiency of the baseline
model scenario and for the optimization process of the different scenarios of the Litani Lower Basin. Strengths, weaknesses,
opportunities and threats analysis was applied in order to derive the objectives and constraints. Results revealed that the
potential retained scenarios aim at decreasing water consumption and demand, losses, and return flow. These scenarios mainly
include the shift to drip irrigation, awareness campaigns, and losses control in domestic supply pipes. Other retained scenarios
having a higher shortfall rely on the use of the Channel concrete lining to decrease losses and return flow, in addition to
the awareness campaigns in both domestic and irrigation sectors, and less consumptive/more efficient irrigation methods such
as sprinkler and drip irrigation at variable application percentages. Hence, most of the interventions or measures proposed
are generally not costly and can be implemented. 相似文献
965.
Groundwater Exploration and Assessment in Rural Communities of Yobe State, Northern Nigeria 总被引:1,自引:1,他引:0
The provision of adequate water supply and sanitation to the rapidly growing urban populations is increasingly becoming a
problem for governments throughout the world. The continuing expansion of the numbers of people in cities who need water and
sanitation services form a continuous pressure to either invest in additional production capacity or to stretch the available
supplies to serve more people. Due to rapid increase in population growth in the Yobe State north of Nigeria, there is a shortage
in the water supply to Damaturu city the capital of the state and surrounding villages. At the present the total water supply
is about 10,000 m3/day abstracted form the shallow alluvial groundwater aquifer using 29 production wells. Due to the expected increase in water
demand and the limited potentiality of shallow aquifer system, other deep aquifers were explored and investigated to evaluate
their potentiality for future water demand. Vertical Electrical Sounding Method was used for the geophysical survey of the
study area. Groundwater flow model was developed and calibrated against the historical information. Three wellfields were
designed to provide Damaturu city and surrounding villages with the required water. The calibrated model has been used to
evaluate the aquifer potentiality and the effect of future withdrawals on the deep aquifer system. It was found that the aquifer
system within the study area consists of two main layers. The upper layer is the Chad formation comprises an alluvial sand
and gravel with intercalation of thin sility clay layers. The second layer is Keri-Keri formation consists of sandstone formation
which is not explored before. During this study the Kerri-Kerri aquifer system was investigated as an alternative source for
groundwater for future demand. The study presents an integrated groundwater resources management strategy for present and
future water supply for rural communities. 相似文献
966.
Groundwater constitutes the largest single source of fresh water in many parts of the world and provides a risk buffer to
sustain critical water demands during cyclic and prolonged dry periods, especially in semi-arid and arid regions. However,
unprecedented socio-economical growths are threatening the viability of these precious resources through fast depletion of
already critically low stocks accompanied by persistent degradation of water quality due to salinization, and contamination
by pesticides and fertilizers, urban sewage and industrial waste. These circumstances are particularly true of the Upper Litani
Basin (ULB), which houses over 500,000 of Lebanon’s 4 million population and provides the bulk of the country’s agricultural
output. Uncontrolled urban, agricultural and industrial growths following a prolonged civil strife and foreign occupation
have resulted in the deterioration of the quality of the basin’s surface water and potentially its groundwater resources.
An assessment study of groundwater quality conditions in the ULB was conducted in support of efforts to manage water quality
in the basin. Geostatistical analysis of groundwater nitrate levels was conducted using data collected through an extensive
basin-wide water quality survey sponsored by the USAID and covered two periods representing the summer and winter periods.
The results of analysis include maps of nitrate contamination and probability of exceedance of drinking-water nitrate regulatory
limit. The results indicate a significant, widespread and persistent nitrates contamination of groundwater in the ULB. Nitrate
levels in groundwater exceed standard limits for drinking water in many parts of the basin. These findings were examined with
respect to those of a DRASTIC groundwater vulnerability assessment conducted by the USAID BAMAS project. Comparative analysis
of the two assessments shed the light on several issues related to the application and interpretation of DRASTIC scores and
the groundwater nitrate contamination process. 相似文献
967.
Water use patterns are not distributed evenly over space and time. Determining the amount of water used within a region, as
well as the various ways in which water is used is important for making adequate and sustainable water management policies
and determining future water availability. We examined differences in spatial trends in Oregon freshwater use (total, municipal,
and agricultural water withdrawals), by county, between the years 1985 and 2005. We also explored biophysical and socioeconomic
factors that explain spatial patterns using Moran’s I, local index of spatial autocorrelation (LISA), and spatial regression
models. There was a moderate positive spatial autocorrelation among counties that had similar total and irrigation withdrawals.
LISA analysis identified hot spots between certain arid agricultural counties in the southeastern Oregon and cold spots between
certain humid northwestern counties, including within the Portland metro area. Annual precipitation and income are negatively
associated with total water withdrawals. Summer temperature and farm size is positively associated with irrigation water withdrawals,
while net cash return and income are negatively associated with irrigation water withdrawals. When compared to ordinary least
square regression models, spatial error models that take into account spatial dependence provide a more comprehensive explanation
of the variations of water use, suggesting that water resource planning and management should incorporate spatial and neighborhood
effects to effective manage limited natural resources. 相似文献
968.
Incorporating Eco-environmental Water Requirements in Integrated Evaluation of Water Quality and Quantity—A Study for the Yellow River 总被引:2,自引:2,他引:0
River water has dual functions; it can be withdrawn for agricultural, industrial, and domestic uses and provides eco-environmental
water (EEW) for riverine systems. A concept of intensity of ecological function of river water (IEFRW) has been put forward,
and an integrated water quantity and quality evaluation method in combination with eco-environmental water requirements has
been developed for a river. Based on the monthly data of water quality and quantity as well as the withdrawals during 1997
to 1999, an integrated evaluation of water resources has been conducted for the Yellow River. The results indicated that actual
IEFRW can directly reflect the health state of riverine ecosystems. The actual increments of water resources availabilities
caused by providing EEW for the riverine systems were lower than the eco-environmental water requirements of the riverine
ecosystem, leading to the intermittent interruption of river flow and other eco-environmental problems of the Yellow River. 相似文献
969.
Water Productivity in a Rigid Irrigation Delivery System 总被引:4,自引:2,他引:2
The rotational irrigation water delivery (warabandi) system practiced in the Indus river basin of Pakistan has continued for 100 years. Irrigation water allocated to the farmers
under the warabandi system is proportional to farm size and is fixed. This rigid allocation system has been partly justified by its contribution
to social equity though this may have been at the cost of economic gains. In order to assess the operation of warabandi’s basic rules, a farmers’ survey was completed from 124 farmers located on five watercourses. A questionnaire was administered
to each farmer and farm management data were gathered. As fresh water resources are under stress and becoming scarce their
efficient use in all applications should be assured in water allocations. It is shown from the survey results that water allocation
based on very limited criteria does not maximize the socio-economic benefits gained from the use of scarce water. Thus, it
is suggested that the existence or non-existence of fresh groundwater resources along with other critical variables should
be taken into consideration when making canal water allocation decisions. Missed water deliveries due to failure of the canal
system appear to be the largest cause of losses. Water charges need to be increased to fund large improvements in canal maintenance
programs. It is pointed out that a framework should be developed as a tool to improve water productivity for Pakistan. This
should include: consideration of the gross area of a tertiary canal, sensitivity of crop growth stage to water shortage, crop
value, bias of allocation towards most water use efficient areas and water use efficient crops, the potential losses from
water deficiency. 相似文献
970.
Conjunctive Management of Large-Scale Pressurized Water Distribution and Groundwater Systems in Semi-Arid Area with Parallel Genetic Algorithm 总被引:2,自引:2,他引:0
Frank T.-C. Tsai Vineet Katiyar Doug Toy Robert A. Goff 《Water Resources Management》2009,23(8):1497-1517
This study develops a production well management model for the conjunctive management of water resources in semi-arid areas.
The management model integrates a large-scale pressurized water distribution system and a three-dimensional groundwater model
under an optimization framework. The well pump operations optimization problem is formulated as a Boolean integer nonlinear
programming (BINLP) problem to optimize the periodic 24-h pump on/off operations over a 1-week operation horizon. The management
model considers multiple objectives and is solved by a parallel genetic algorithm (PGA) to overcome the difficulty of solving
the BINLP problem. The PGA significantly reduces computation time for a case study in Chandler, Arizona. The Chandler water
distribution model is built based on EPANET, and the Chandler three-dimension groundwater model is developed using MODFLOW.
The high performance computing (HPC) of the genetic algorithm makes it possible to obtain 24-h real-time operations in the
7-day forecast model. The tank reliability, resilience, and vulnerability (R-R-V) are evaluated to infer the system reliability.
The Pareto curve provides compromise solutions between the two competing objectives of energy reduction and pressure violation
reduction. 相似文献