对台州市北水南调工程的探讨

介绍台州市南片水资源供需发展预测，水资源的平衡、调配及措施，北水南调及西线一期的前期工程概况，跨流域引水的合理性和可行性。并提出实施工程运作机制的方向和指导原则。     

Economic valuation of irrigation water in south-eastern Mexico

Ongoing discussion on new water legislation in Mexico emphasizes the need to consider the economic dimension of water. Using the net income change method, in this article the economic value of irrigation water is estimated for banana cultivation in the state of Tabasco, which is a tropical region with high rainfall. The main results show that irrigated farms are 34–37% more profitable than rainfed ones with similar revenue levels, with corresponding water values of 1.48–1.75 USD/m³. These values are a proxy of farmers’ maximum willingness to pay, and can be used to inform tariff reform.     

南水北调山东段水资源优化配置研究

针对南水北调沿线受水区水资源供需矛盾十分突出的问题,以东线山东段为研究对象,研究南水北调受水区水资源供需平衡问题。受水区水资源配置是一个涉及多水源,多用途,不同区域的复杂问题。本文运用大系统分解协调原理,建立水资源优化调度模型,运用优化技术对模型进行求解,给出了优化决策算法的程序框架图,合理解决了多水源、多目标、多用户、多保证率的水资源配置问题,研究结果可为同类问题提供依据。     

Spain's Ebro river transfers: Test case for water policy in the European Union

The USA's 20th-century experience with major subsidized water development left a plethora of problems. Another generation now struggles with how to correct them. Today there is consensus among experts that water policy should be the result of broad public participation and should consider the social, economic and environmental effects of water use and development. Yet, formal institutions in the USA have been slow to incorporate innovations reflecting this consensus. The European Community's (EC's) Water Framework Directive and Spanish water law, however, appear to embody a progressive approach to water policy. Criticisms of Spain's proposed Ebro River transfers cast doubt on whether they would conform to Spanish or EC policy. The paper concludes that before the Ebro proposal proceeds it should be judged rigorously, according to policies expressed in Spanish law and the Directive.     

美国、墨西哥水利工程建设与水生态保护的几点启示

在与美国、墨西哥等地水利、环保等部门的座谈交流和实地调研的基础上,本文梳理两国在水利工程建设与水生态保护方面的基本经验,结合江西省水利工作相关需求,从全面推进鄱阳湖流域综合管理、注重水利工程建设模型试验、实现水体生态监测和改进水利科研管理模式等4个方面提出几点启示,为实现鄱阳湖的健康、绿色发展提供参考.     

Initial appraisal of water quality of Lake Santa Ana,Mexico

Lake Santa Ana is located in the Mexican central plateau, a semiarid region characterized by low rainfall and high evaporation rates. Because of the area's climatic conditions, most of its few existing lakes and reservoirs are ephemeral, with significantly reduced surface areas during the dry season. Mexican authorities currently pay little or no attention to these special aquatic ecosystems. As a consequence, several of these waterbodies are severely degraded in regard to both water quantity and quality. As a result, this report describes Lake Santa Ana as a case study. Several water quality parameters, including physicochemical, microbiological and heavy metal concentrations, were measured at eight sampling sites in the lake, and four sites in the lake basin, in 2005. Some dissolved ions were also analysed in 2007 in the lake, and in a well located close to the lake, in order to evaluate possible interactions between groundwater and surface waters. These study results indicate that the lake does not have significant interactions with groundwater in the local aquifer. Most of the measured water quality parameters do not meet the international suggested standards for inland surface waters to sustain aquatic life, and preserve the habitat for both endemic and migratory waterfowl. Loss of aquatic habitats puts at risk the value of the central portion of Mexico as a migratory route for North American waterfowl species.     

The application of economic-engineering optimisation for water management in Ensenada, Baja California, Mexico.

Mathematical optimisation is used to integrate and economically evaluate wastewater reuse, desalination and other water management options for water supply in Ensenada, Baja California Mexico with future levels of population and water demand. The optimisation model (CALVIN) is used to explore and integrate water management alternatives such as water markets, reuse and seawater desalination, within physical capacity constraints and the region's water availability, minimising the sum of economic costs of water scarcity and operating costs within a region. The modelling approach integrates economic inputs from agricultural and urban water demand models with infrastructure and hydrological information, to identify an economically optimal water allocation between water users in Ensenada. Estimates of agricultural and urban economic water demands for year 2020 were used. The optimisation results indicate that wastewater reclamation and reuse for the city of Ensenada is the most economically promising alternative option to meet future water needs and make water imports less attractive. Seawater desalination and other options are not economically viable alone, but may have some utility if combined with other options for the Ensenada region.     

Capacity Building in Mexico

An analysis of water quality and quantity in Mexico is presented. The tasks of the National Water Commission, the nation's water authority, are described. Advances in the planning of the Capacity Building Project are presented in three aspects: human resource formation, strengthening of institutional and community participation, and the adoption of an adequate environmental policy. The projects listed were selected by specialists from universities, NGOs, public, social and private institutions, and international and financial organisms in five areas: urban and rural drinking water and sanitation systems; environmental impact and water quality; integral planning and management of hydraulic resources; and hydroagricultural development and hydrometeorology.     

An evaluation of inter-basin water transfers as a mechanism for augmenting salmonid and grayling habitat in the River Wear,North-East England

Transfers of water from the Kielder system have been used for 12 years to avoid low flow problems in the River Wear. Transfers are scheduled to avoid breaches of the river's statutory Minimum Maintained Flow (MMF). Despite this routine use, the role of transfers in augmenting instream habitat has never been evaluated. A physical habitat simulation (PHABSIM) study was undertaken in 1996 to investigate the influence of transfers and the MMF policy on brown trout Salmo trutta, Atlantic salmon Salmo salar and grayling Thymallus thymallus instream habitat at three sites on the Wear. Transfers support total habitat levels up to 10% greater than unregulated conditions. They impact usable instream habitat (weighted usable area) to a much greater extent. For salmon parr, the species/lifestage whose habitat is most limited by low flows, transfers have maintained relatively stable usable habitat levels during periods when otherwise they would have fallen by as much as 70%. The MMF policy results in minimum flow values which are higher than those which would have been set using the Montana Method and the availability of salmon parr usable habitat does not fall below 10% of its mean annual value. Judged in these terms, the MMF-based transfer regime has played a positive role in avoiding extreme habitat loss in the Wear. Simulations of four alternative Kielder transfer release policies indicate that near-optimum habitat levels could be maintained throughout summer low flow periods. However, this would result in unnatural temporal patterns of flow and habitat availability. © 1998 John Wiley & Sons, Ltd.     

A review of the effects of water transfers in the La Grande Hydroelectric Complex (Québec,Canada)

Construction of the La Grande Complex in Eastern Canada called for complete or partial diversion of six rivers, the mean annual discharge of which varied from 60 to 1600 m³ s^?1, and the transfer of water from two adjoining watersheds (1586m³ s^?1) into La Grande Rivière. Three of these rivers with reduced flow, Eastmain (from 700 to 95m³ s^?1), Opinaca (from 260 to 35m³ s^?1), and Caniapiscau (from 1708 to 960m³ s^?1) and the waterways with increased flows, Boyd-Sakami (from 1 to 811m³ s^?1) and La Grande Rivière (from 1760 to 3400m³ s^?1) were intensively monitored from 1978 to 1988, while the others were surveyed sporadically. Very few modifications were observed, compared to previous conditions, in banks stability, water quality, and aquatic fauna of the affected rivers: those which appeared can be explained by the water level fluctuations, the water quality of the tributaries of the residual drainage basin, and/or by the direct influence of the reservoirs. In James Bay, the areal extent of the Eastmain River and La Grand Rivière plumes varied with discharge in an exponential relation, mostly under ice cover; resources from the coastal environment had not yet undergone any major changes. Because of the very small population dwelling in the area, less than 3000 inhabitants, modifications in the hydrological regime of these rivers did cause relatively few impacts, the main being greater banks instability in specific locations, reduction of the thickness and ice cover on La Grande Rivière, enhancement of navigation constraints on Eastmain River, and higher mercury levels in fish related to operation of the reservoirs.     

Hazard identification framework for water utilities with application to the city of Xalapa,Mexico

Abstract:

There is a growing need for a comprehensive approach for assessing drinking water systems that enables managers and engineers to quickly address critical hazards that impact their water supply systems and plan for system improvements. A hazard identification framework for water utilities is developed and applied to the municipal water supply system at Xalapa, Veracruz, Mexico, operated by the Comisión Municipal de Agua Potable y Saneamiento de Xalapa (CMAS Xalapa). The framework is designed to aid in the analysis of a water supply system from catchment to tap and consists of four components: system characterization, identification of hazards, assessment of the impacts of the major hazards, and determination of priority recommendations for system improvements. When the framework is applied to the CMAS Xalapa system, a number of significant hazardous events are identified including elevated turbidity events and high pressure surcharges. Recommendations for system improvements include increased data collection and analysis and enhanced management of control measures for mitigating the impacts of the hazards.     

Effect of irrigation water quality on organic matter, Cd and Cu mobility in soils of Central Mexico.

Untreated wastewater has been used for irrigation since 1912 at the Irrigation District 03, Central Mexico. Accumulated heavy metals are dominantly bound to the organic soil fraction. In a field study we evaluated the effect of wastewater irrigation on the quality of soil organic matter and the amount of water extractable Cu and Cd. In a column experiment we tested if water treatment affects the leaching of both metals and dissolved organic carbon (DOC) out of soils that have been irrigated for more than 90 years with untreated wastewater. The field study shows that long term irrigation increases the mineralizable carbon fraction and the DOC concentrations. The water extractable Cu and Cd concentrations also increase and correlate with DOC. In the column leachates the Cu concentrations also correlate with DOC, the Cd concentrations correlate with the sum of cations, chloride and DOC concentrations. Water treatment reduced Cd leaching, but it did have no substantial effect on Cu leaching.     

Phosphates in Lake Chapala, Mexico

Lake Chapala, the most important lake in Mexico, has suffered from cultural eutrophication problems for many years, manifested by the growth of aquatic vegetation and an increase in primary productivity. It was found that about 70% of the total phosphorus entering Lake Chapala is orthophosphate, thus increasing the biological availability of nutrients in the lake. In addition, the hydrologic imbalance in the lake, caused by the over‐use of water resources along the Lerma–Chapala basin, has significantly increased the hydraulic residence time of the inflow waters, thus increasing the effects of the added phosphorus, and creating conditions that increase the lake’s eutrophication status. The shallow characteristics of the lake and the action of the wind forces produce rapid changes in water quality, especially in the distribution of phosphate. The focus of this paper is on the development of a historical orthophosphate balance in Lake Chapala, quantifying the main point and non‐point sources that contribute to the enhancement of this nutrient in the lake. The estimation of the amount of phosphate in the lake can be used to determine appropriate management practices to reduce the phosphate loads on the lake.     

Reuse of oil and gas produced water in south-eastern New Mexico: resource assessment,treatment processes,and policy

The Permian Basin of south-eastern New Mexico in the United States exemplifies the combination of rapidly expanding oil and gas production with freshwater shortages and aquifer stress. Reuse of saline produced water can provide a stable supply of water for drilling, fracturing and completion and minimize consumptive use of freshwater. We discuss water withdrawals and use by the oil and gas industry in this region, processes for reuse and recycling of produced water in place of freshwater, and operational and policy changes to help improve maximal use of all available water resources in this arid region.     

Planktonic indicators of water quality: A case study in the Amacuzac River Basin (State of Morelos,Mexico)

Planktonic organisms are good indicators of water quality but are rarely used in Mexican riverine studies in spite of the high level of contamination in these lotic waters. In this study, we focused on the plankton of the river Amacuzac in Mexico and a large saline waterbody, Lake Tequisquitengo, which is located in the Amacuzac river basin. We collected samples at three sites in the River Amacuzac and one at Lake Tequisquitengo from May 2015 to March–April of 2016. We analysed the physicochemical variables, coliform bacteria, and biological oxygen demand levels. We also quantified phytoplankton and zooplankton. Our results indicate that the study sites are mesotrophic with high densities of diatoms and cyanobacteria. Among the zooplankton, the dominant organisms were rotifers. The constancy of planktonic taxa was high in the lake but low in the river. The Descy index ranged from 2.9 to 4.5 in the river and from 4.0 to 5.0 in the lake. The saprobic index shows that the system is β‐mesosaprobic. The species diversity was higher in the river than in the lake. Our study shows that plankton can efficiently be used to evaluate the water quality in rivers and lakes.     

Environmental Management of Water Resources in Mexico

ABSTRACT

The environment has been receiving high priority in Mexico in recent years. The country however is presently facing numerous environmental problems. These problems are already severe, and the financial and human resources available are limited. While a good beginning has been made, much more remains to be done.