Thesis (M. Sc.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 138-145).

Ãgua à um recurso essencial para o desenvolvimento social e econÃmico como tambÃm para manutenÃÃo saudÃvel dos ecossistemas. Devido sua importÃncia econÃmica e social à fonte de conflitos sociais entre os setores interessados em adquiri-la e usufruÃ-la, sendo a Ãpoca de escassez o momento de maior conflito. Assim, como forma de harmonizar conflitos de interesses entre os setores, este trabalho objetivou pesquisar e desenvolver mecanismos financeiros de gestÃo do risco climÃtico em recursos hÃdricos, fundamentado em seguro baseado Ãndice associado a contrato de opÃÃo e fundo financeiro que possibilitem menores variaÃÃes nos preÃos dos recursos hÃdricos, tendo como critÃrio o princÃpio da compensaÃÃo aos usuÃrios pela transferÃncia hÃdrica quando das falhas no abastecimento. A metodologia de avaliaÃÃo dos recursos financeiros que satisfizessem os setores foi a quantificaÃÃo econÃmica dos recursos transferidos a partir das equaÃÃes de benefÃcios especÃficas dos setores. Os valores dos recursos hÃdricos transferidos foram obtidos por meio da permuta de metodologia de alocaÃÃo: sistema de prioridades e rateio linear. Foram simulados cinco cenÃrios que dividiam as disponibilidades hÃdricas entre dois setores (irrigaÃÃo e urbano) com os seguintes coeficientes, respectivamente, para esses setores (0,10; 0,90), (0,25; 0,75), (0,50; 0,50), (0,75; 0,25) e (0,90; 0,10) para as garantias de 98%, 95% e 90%. Os pagamentos de opÃÃes fundamentados nos contratos de opÃÃes apresentaram linhas de tendÃncias semelhantes aos impactos negativos da irrigaÃÃo (perdas), porÃm com valores abaixo destes para todos os intervalos e garantias simulados. As perdas cresceram atà o cenÃrio de coeficientes (0,52, 0,48), a partir do qual os impactos econÃmicos do setor urbano (ganhos) superam aos da irrigaÃÃo. No entanto, para os cenÃrios de coeficientes acima de (0,90, 0,10), os ganhos diminuem a valores abaixo dos das perdas. Quanto ao fundo financeiro, somente para os cenÃrios com coeficientes localizados entre (0,50, 0,50) e (0,90, 0,10), considerado cenÃrios viÃveis, à que esse fundo possui viabilidade financeira, sendo, dentre os cenÃrios simulados, o de coeficientes (0,75, 0,25) que possui os maiores valores acumulados. Por fim, conclui-se que a viabilidade econÃmica das transferÃncias hÃdricas se concentrou apenas nos cenÃrios localizados entre os coeficientes (0,50, 0,50) e (0,90, 0,10). AlÃm disso, conclui-se que a associaÃÃo entre contrato de opÃÃes, seguro baseado no Ãndice vazÃo liberada e fundo financeiro pode contribuir para um entendimento mÃtuo entre os setores interessados nos recursos hÃdricos locais/regionais quanto à necessidade de se harmonizarem, principalmente, nos momentos mais conflituosos, no caso, Ãpocas de escassez hÃdrica. / Water is an essential resource for the social and economic development and to maintaining healthy ecosystems. Due to its economic and social importance is a source of social conflict between the sectors interested in acquiring it and enjoy it, being the lean season far more conflict. So, as a way to harmonize conflicting interests among sectors, this study aimed to investigate and develop financial mechanisms for climate risk management in water resources based on index-based insurance associated option contract and financial background to enable minor variations in resource prices water tended as the principle of compensation to users for transfer when the water supply disruption. The valuation methodology of financial resources that met the sectors was the quantification of economic resources transferred from the equations of specific benefits of sectors. The amounts of transferred water was obtained through the exchange of allocation methodology: linear priorities and assessment system. Five scenarios that divided water availability between two sectors (irrigation and urban) with the following coefficients, respectively, for these sectors (0.10, 0.90), (0.25, 0.75) were simulated, (0, 50, 0.50), (0.75, 0.25) and (0.90, 0.10) for guarantees of 98%, 95% and 90%. Payments of options based on options contracts had lines similar to the negative impacts of irrigation (losses) trends, but with values below these intervals for all warranties and simulated. Losses grew to the scene of coefficients (0.52, 0.48), from which the economic impacts of the urban sector (gains) outweigh the irrigation. However, scenarios for the above coefficients (0.90, 0.10), the gain values decrease below losses. On financial background, only for scenarios with localized coefficients between (0.50, 0.50) and (0.90, 0.10), considered viable scenarios, is that this fund has financial viability, being among the scenarios simulated, the coefficients (0.75, 0.25) having the highest accumulated values. Finally, it is concluded that the economic viability of water transfers only focused on scenarios located between the coefficients (0.50, 0.50) and (0.90, 0.10). Furthermore, it is concluded that the association between options contract based insurance index released flow and financial background can contribute to mutual understanding between the sectors interested in local / regional on the need to harmonize, especially in times water more conflicting in the case, times of water scarcity.

No description available.

La ville de Tamanrasset comme une ville récente du Sahara central, a été confrontée au long de son histoire à un problème d’approvisionnement en eau potable. Cette situation qui endure la population de la ville a dû d’une croissance démographique rapide (sédentarisation, immigration), une urbanisation anarchique et à des ressources en eau très limites. Avec, la persistance de la pénurie, les difficultés d’accès à l’eau potable, et une gestion étatique inefficace, les habitants ont toujours fait recours aux services des revendeurs d’eau par les camions-citernes, et ont développé des dispositifs de stockage plus au moins sophistiqués pour assurer une consommation régulière à l’intérieur de l’habitation, tout en étant indépendant du programme de rotation du distribution élaboré par l’A.D.E. Pour résoudre le problème de la pénurie d’eau ; il a fallu attendre l’intervention de l’état algérien par la réalisation d’un grand projet d’adduction en transférant des eaux fossiles (albienne) du bas Sahara vers la ville de Tamanrasset (700 km). Il est à signaler que ce passage d’une gestion de pénurie vers celle d’abondance reste un défi qui nécessite plus de moyens et d’attention. D’une manière plus précise, le travail que nous avons mené concerne les interactions entre le rationnement, imposé par les services de l’eau de la ville en conséquence du manque d’eau et d’une politique de gestion inadéquate avec les spécificités locales, et les solutions envisagées par les usagers et l’état. / The city of Tamanrasset as a new city in the central Sahara was faced throughout its history to a water supply problem. This situation endures the population of the city had a rapid population growth (settlement, immigration), uncontrolled urbanization and limits water resources. With the persistence of the shortage, lack of access to safe drinking water, and inefficient state management, people have always used the services of water reseller’s tankers, and developed storage devices more or less sophisticated to ensure regular consumption in within the housing, while being independent of rotation program distribution developed by the ADE. To solve the problem of shortage of water, it took the intervention of the Algerian state by carrying out a large supply project by transferring fossil water (Albian) of the down Sahara to the city of Tamanrasset (700 km). It should be noted that the passage of a management shortage to abundance that remains a challenge requiring more resources and attention. More specifically speaking, the work we've done for the interactions between the rationing imposed by the water services in the city as a result of lack of water and inadequate management policy, with specific local and the solutions envisaged by users and the state.

This dissertation is composed of three essays investigating three aspects of future water issues. The first essay focuses on an examination of water scarcity issues caused by rapid population growth and economic development in Texas. The second essay examines water scarcity under climate change scenarios in Texas. The third essay discusses arsenic-related water quality issues in the drinking water. An integrated economic, hydrological, and environmental model is developed for the first two essays by implicitly incorporating uncertainty about future climate, water demand from all types of water use, a spatial river flow relationship, interaction between ground and surface water, institutional regulations, and the possibilities of inter-basin water transfers (IBTs). In studying water scarcity under economic growth and population growth, we find that while some cities and counties have sufficient water, there are some other cities and counties (especially Dallas, Fort Worth and Austin) facing different degrees of water scarcity problems. In studying the climate change impact, four Global Circulation Models (GCMs) with three Special Report on Emissions Scenarios (SRESs) yield consistent results. Water scarcity becomes even more severe for cities. Texas realizes slight gains in earlier periods and a net loss beginning in 2060. This study finds that twelve IBTs, if there is no climate change, and fourteen IBTs, under the climate change scenario, will be economically feasible in 2060. These IBTs can not only greatly reduce water scarcity, but also create new growth opportunity for Houston. Water is transferred from in-stream flow in source basins. There is no significant impact on other sectors except in-stream flow and water flow out to bay. In the third essay, a two-stage structural model is developed to model household risk-averting behavior with respect to arsenic-related mortality risk in the drinking water. The empirical results suggest that risk perceptions for the parents and children are important in the decision of how much to spend on water treatment, but not in whether or not to treat water. Parents in our sample displayed mixed altruism. The information generated by this dissertation can help state agencies to manage water resources and to improve water-related human health, especially health for children, more effectively and more efficiently.

Le bois possède des propriétés physiques remarquables mais qui dépendent étroitement du taux d’humidité dans le matériau. Du fait de sa structure multi-échelle et des différents états de l’eau dans le bois, les mécanismes de transferts d’eau dans le bois sont encore mal appréhendés. Nous étudions les phénomènes physiques essentiels à l’origine des propriétés d’imbibition et de séchage du bois de feuillu. On montre d’abord par des expériences macroscopiques classiques, que la dynamique d’imbibition d’eau dans le bois est significativement ralentie (plusieurs ordres de grandeur) par rapport aux prédictions du modèle de Washburn utilisant la perméabilité et la mouillabilité du bois mesurées indépendamment. Les distributions d’eau liée et d’eau libre obtenues par IRM au cours de l’imbibition montrent que l’eau liée adsorbée dans les parois cellulaires progresse en fait (par diffusion) plus vite que l’eau libre dans les pores. Il faut attendre que les parois soient saturées en eau liée pour que l’eau libre avance à son tour dans les lumens du bois. L’analyse des images tomographiques aux rayons X suggèrent que le ralentissement de la pénétration d’eau liquide dans le bois est dû à la modification des conditions de mouillage par la teneur en eau liée dans les parois. Les expériences d’imbibition avec un « bois artificiel » à base d’hydrogel confirment cette hypothèse. Finalement, l’étude du séchage du bois par IRM montre également différentes dynamiques de séchage pour l’eau liée et l’eau libre. Le séchage du bois est contrôlé par l’évaporation d’eau libre à partir d’un front sec à des teneurs en eau élevées. L’évaporation d’eau liée ne devient significative qu’à partir de la disparition totale de l’eau libre / Wood has excellent physical properties which however depend closely on the moisture content in the material. Because of its multi-scale structure and different states of water existing in the material, the mechanisms of water transfers in wood are still poorly understood. The essential phenomena at the origin of imbibition/drying properties of hardwood are studied in this thesis. We first show with classical macroscopic measurements that, water imbibition in wood is significantly damped compared to Washburn’s law which predicts the dynamic of capillary imbibition in the porous medium. The bound water and free water distributions obtained by MRI during imbibition show that, the bound water adsorbed in cell walls diffuses more quickly than the free water located in the pores. Free water cannot penetrate in the pores unless the cell walls have been saturated with bound water. The tomographic image analysis reveals that the damped dynamic of liquid water penetration in wood is due to the modification of wetting conditions by bound water content in the cell walls. Imbibition Tests with a hydrogel-based “artificial wood” confirm our hypothesis. Finally, the observations of wood drying by MRI show also different drying dynamics for bound and free water. At high moisture content, wood drying is controlled by the evaporation of free water from a dry front. Bound water starts to evaporate significantly only after the total disappearance of free water

Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: South Africa‟s hydrological and geographical characteristics, coupled with the location of a large part of its mineral endowment, required the development of the complex Vaal River Supply System, including inter-basin water transfer (IBT) projects which have been in operation for over twenty-five years. This research compares the actual water transfers of two such IBTs with their original, appraisal stage, predictions. Transfers are shown to be significantly less and also more variable than predicted. Further research reveals that the state of the receiving system has a large bearing on year-to-year decisions regarding transfers. Past appraisals, following what is called the Incremental Approach, do not adequately consider the likely future inter-basin transfer operating regime. Examination of six case studies, four South African, one Chinese and one Australian, shows that the Incremental Approach is still in general use – despite tools available for an improved approach. A new approach is proposed to upgrade estimations of variable costs associated with water transfers – often substantial life-cycle cost components of IBTs. The generally used unit reference value (URV) measure for appraising and ranking water resource projects in South Africa is also rooted in the economic theory of cost-effectiveness. This shows that the current approach is conceptually flawed; it fails to distinguish between water transfers and effectiveness outputs. The determination of the URV equation is expanded and improved. The upgraded appraisal approach, inclusive of the improved URV methodology, is named the Comprehensive Approach. A step-wise demonstration of the Comprehensive Approach is provided. Uncertainty regarding future water transfers and associated variable costs are provided for by stochastic simulation modelling. Decision analysis theory is applied to obtain the appropriate input value of variable costs. It is shown that the Comprehensive Approach can lead to an outcome significantly different from the Incremental Approach. The research provides new insights, placing water resource planning practitioners in a better position to recommend appropriate IBTs in future. These insights can also be transferred to the design of institutional and financial models related to IBTs, as well as the configuration and operation of supply systems including sea-water desalination projects. / AFRIKAANSE OPSOMMING: Suid-Afrika se hidrologiese en geografiese eienskappe, gekoppel aan die ligging van 'n groot deel van sy minerale bates, het gelei tot die ontwikkeling van die komplekse Vaalrivier Voorsieningstelsel, insluitend tussen-bekken oordragskemas waarvan sommige al vir meer as vyf-en-twintig jaar in werking is. Hierdie navorsing vergelyk die werklike wateroordragte van twee sulke oordragskemas met die oorspronklike vooruitskattings tydens die beplanning-stadium. Daar word getoon dat oordragte noemenswaardig minder en ook meer onreëlmatig was as wat voorspel is. Verdere ondersoek toon dat die stand van die stelsel, aan die ontvangskant, die besluitneming rakende die jaar-tot-jaar oordrag beïnvloed het. Historiese evaluerings het 'n “Inkrementele Benadering” (soos hier genoem) gevolg, wat nie voldoende die toekomstige bedryfsomgewing ten opsigte van tussen-bekken oordragte inagneem nie. Ondersoek van ses gevalstudies, vier Suid-Afrikaans, een Sjinees en een Australies, toon dat die Inkrementele Benadering nog algemeen in gebruik is, ten spyte daarvan dat hulpmiddels vir 'n verbeterde benadering beskikbaar is. 'n Nuwe benadering word voorgestel vir die verbetering van vooruitskattings van veranderlike koste wat met wateroordragte geassosieer word – dikwels 'n aansienlike gedeelte van die lewenssiklus-koste van sodanige skemas. Die Eenheidverwysingswaarde (EVW) maatstaf, wat algemeen in Suid-Afrika gebruik word om waterbronprojekte te beoordeel en in rangorde te plaas, word ook geanker in die ekonomiese teorie van koste-effektiwiteit. Daarmee word getoon dat die huidige gebruik van die EVW konsepsioneel gebrekkig is; dit tref nie 'n onderskeid tussen wateroordragte en effektiwiteitsuitsette nie. Die bepaling van die EVW vergelyking is verbreed en verbeter. Die opgegradeerde benadering, met insluiting van die verbeterde EVW metodiek, word die Omvattende Benadering genoem. 'n Stapsgewyse uiteensetting van die Omvattende Benadering word voorsien. Onsekerhede ten opsigte van wateroordragte en geassosieerde veranderlike koste word deur middel van stogastiese modellering aangespreek. Besluitnemingontledingsteorie word ingespan om die toepaslike insetwaarde van die veranderlike koste te bepaal. Daar word getoon dat die Omvattende Benadering tot 'n resultaat kan lei wat aansienlik verskil van wat met die Inkrementele Benadering verkry word. Die navorsing verskaf nuwe insigte wat die waterbronbeplanner in 'n beter posisie sal plaas om gepaste tussen-bekken oordragskemas voor te stel. Hierdie insigte kan ook oorgedra word na die ontwerp van institusionele en finansiële modelle rakende oordragskemas, asook die uitleg en bedryf van voorsieningstelsels, insluitend seewater-ontsoutingsaanlegte.

published_or_final_version / abstract / toc / China Area Studies / Master / Master of Arts

A região Nordeste, primeira a ser ocupada após a chegada dos portugueses no Brasil no século XVI, possui 53% do seu território sob regime do clima semiárido. Nesse espaço, onde vivem 12 milhões de pessoas, as crises causadas por escassez de água, apontadas como barreiras ao desenvolvimento, são conhecidas há mais de um século, causaram perdas agrícolas, migrações e mortes. A região, de conhecida variabilidade climática, é ainda uma das mais vulneráveis do globo às mudanças climáticas. Até o fim desse século, previsões indicam que a temperatura pode subir 4 C em relação à era pré-industrial, com forte impacto sobre os recursos hídricos e desertificação. Diante desse cenário, medidas que oferecem às populações locais condições de se adaptarem se fazem urgentes. Proposto há mais de um século como solução dos problemas trazidos pela escassez de água no semiárido, a transposição do rio São Francisco passou a ser implantada a partir de 2007 sob nome oficial de Projeto de Integração do rio São Francisco com as Bacias Hidrográficas do Nordeste Setentrional (PISF). Trata-se da maior obra de infraestrutura hídrica do país, projetada para transferir 26,4 m3/s por dois eixos principais, Norte e Leste, o volume transportado pelos canais é destinado principalmente ao consumo humano e dessedentação animal. Esta dissertação tem o objetivo de analisar o Eixo Leste do PISF como potencial medida de adaptação às mudanças climáticas. A estratégia de investigação aplicada nesse trabalho interdisciplinar se enquadra na pesquisa qualitativa, apoia-se em documentos, imagens, entrevistas não estruturadas e visitas de campo. A pesquisa conclui que a distribuição de água feita pelo Eixo Leste do PISF não contribui para que as populações mais vulneráveis do semiárido se adaptem às mudanças climáticas, mas que o projeto tem potencial para se converter em tal medida. / The Brazilian Northeast region, the first to be occupied after the arrival of the Portuguese in the 16th century, has 53% of its territory under a semi-arid climate regime. This space is home to 12 million people, it has been hit by crises caused by water shortages, which are understood as barriers to development. Known by its climatic variability, the semiarid portion of the Northeast is one of the world\'s most vulnerable region to climate change. By the end of this century, predictions indicate that temperature could rise by 4 C as compared to the pre- industrial time, with a strong impact on water resources and desertification. Given this scenario, it is urgent to discuss measures that offer the local population conditions to adapt. Proposed more than a century ago as a solution to the problems brought about by the water scarcity in the semiarid, the project to divert Brazil\'s Sao Francisco river began to be implemented in 2007 under the official name of the São Francisco River Integration Project with the Northern Northeast Hydro Basins (PISF). It is the largest water infrastructure project in the country, designed to transfer 26.4 m3/s through two main axes, Northern and Eastern. The volume transported by the channels is mainly intended for human and animal consumption. This dissertation aims to analyze the Eastern Axis of the PISF of the Northeast of Brazil as a potential adaptation to climate change measure. The research strategy applied in this interdisciplinary work fits the qualitative research, relies on documents, images, unstructured interviews and field visits. The research concludes that the distribution of water by the Eastern Axis of the PISF does not contribute to the adaptation of most vulnerable populations in the semiarid region, but that PISF has the potential to convert to that such measure.

Le palmier-dattier constitue une des rares cultures à vocation alimentaire adaptées aux conditions climatiques extrêmes (sécheresse, salinité), telles que rencontrées à Djibouti. Dans un contexte de ressources en eau fortement limitées, la connaissance des modalités de l’alimentation hydrique du palmier dattier est essentielle. L’objectif de ce travail de recherche est d’acquérir cette connaissance, dans le contexte pédoclimatique de Djibouti, par la réalisation d’un suivi in situ du fonctionnement hydrique du système sol-palmier, à l’échelle d’un individu, et la quantification du puits racinaire du palmier-dattier. Un palmier-dattier, pleinement développé, a été instrumenté à l’échelle de la cuvette d’irrigation, à l’aide de plusieurs tubes d’accès de sonde à neutrons, pour le suivi de la teneur en eau volumique du sol, et de plusieurs tensiomètres, répartis de 10 à 160 cm de profondeur. Trois expériences d’infiltration/redistribution a été réalisées successivement, la première sans altérer le fonctionnement du système sol-palmier, la seconde après avoir coupé le palmier, tout en permettant l’évaporation de la surface du sol, la dernière après avoir couvert la surface du sol afin d’empêcher l’évaporation. Les résultats mettent en évidence une forte hétérogénéité des propriétés hydriques du sol, avec une stratification liée au contexte sédimentaire littoral. L’impact du puits racinaire sur la dynamique hydrique du sol est observé jusqu’à 80 cm de profondeur. Pour la période fraîche, les besoins en eau du palmier dattier sont estimés à 130 L par jour, avec une fréquence d’irrigation d’une fois toutes les 2 semaines. Pour la première fois, le coefficient cultural du palmier dattier (kc = 1,39) a été établi dans les conditions climatiques de Djibouti. Les résultats obtenus contribueront à une meilleure gestion de l’irrigation et à une meilleure maîtrise du risque de salinisation du sol dans le contexte pédoclimatique de la République de Djibouti. / Date palm is one of the few food crops adapted to the extreme weather conditions (drought, salinity), such as encountered in Djibouti. In the context of highly limited water resources, knowledge of the date palm water requirements is essential. The objective of this research was to determine the date palm water requirements, in the Djibouti pedoclimatic context, using in situ monitoring of water transport in the soil-plantatmosphere system, at the scale of a single date palm tree, and to quantify the date palm root water uptake. A fully developed date palm tree was instrumented at the irrigation basin scale, using several access tubes for neutron probe for monitoring the soil volumetric water content, and several tensiometers, installed from 10 to 160 cm depth. Three infiltration/redistribution experiments have been performed successively, the first without alteration of the soil-plant system, the second after cutting off a date palm tree while allowing the surface evaporation, the last with covering the soil surface to avoid evaporation. The results show large heterogeneity in soil hydraulic properties, with stratification linked to the coastline sedimentary context. The root water uptake is observed up to 80 cm depth. The date palm water requirements in the fresh period are estimated at 130 liters per day with a frequency of irrigation of one time every two weeks. For the first time, the date palm cultural coefficient has been established in the Djibouti climatic conditions (kc = 1.39). The obtained results will contribute to better management of irrigation and to improve the control of soil salinization in the pedoclimatic context of the Republic of Djibouti.