Thesis (Ph. D.)--University of Bonn, 2001. / Includes bibliographical references (p. 119-126).

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2000. / Includes bibliographical references.

Zugl.: Hamburg, Universiẗat Diss., 1999. / Hergestellt on demand. - Zugl.: Hamburg, Univ. Diss., 1999.

Organisation und Management zur verbesserten Wassernutzung in der Landwirtschaft des Sudan - eine empirische Studie Der Sudan, das größte Land Afrikas, kann stellvertretend gesehen werden für die Probleme, die den afrikanischen Kontinent bewegen. An erster Stelle ist die Ernährungssicherung für eine steigende Bevölkerungszahl anzusehen. Bei Betrachtung der Dürre-Probleme dieser Region, die ihren Höhepunkt Mitte der 80er Jahre hatten, wird das Thema Bewässerung zunehmend zu einem Pfeiler, wenn es um die Verbesserung der Nahrungsmittelversorgung geht. Dieser Sub-Sektor spielt, historisch gesehen, eine wichtige Rolle für die Produktion von Nahrungsmitteln und landwirtschaftlichen Exportprodukten im Sudan. Jedoch gibt es zunehmende Anzeichen dafür, daß die Ausdehnung der Bewässerungssysteme generell in Konfrontation mit einer beschränkten Verfügbarkeit von Fremdwährung und Wasserressourcen stehen wird. Die erste Beschränkung ist abhängig von der Leistungsfähigkeit der sudanesischen Wirtschaft und die zweite von den Plänen anderer Länder. Da der erste Faktor seinen kritischen Punkt erreicht hat, ist es klar, dass Wasser, und nicht andere Ressourcen, die entscheidende Rolle bei der Entwicklung der Bewässerungssysteme spielen wird. Somit ist es notwendig, wenn die sudanesische Landwirtschaft entwickelt werden soll, das Management der Wassernutzung und die damit verbundenen organisatorischen Rahmenbedingungen zu vervollkommnen. Folglich war es die Hauptaufgabe der Studie, die Faktoren, die dem Ziel einer wirtschaftlichen Wassernutzung hinderlich sind, herauszuarbeiten. Die Studie teilt sich in zwei Abschnitte. Der erste Teil setzt sich mit den theoretischen Rahmenbedingungen relevanter Konzepte und Ansätze auseinander. Es werden die verschiedenen Aspekte, die Einfluß auf die Leistungsfähigkeit von Bewässerungssystemen haben, hervorgehoben. Dabei werden besonders Technologie und Umwelt betont. Zusätzlich werden die Bedeutungen und Bedingungen des Institutionellen Wandels diskutiert. Der zweite Teil der Studie widmet sich der Empirie, d.h. den Methoden und Ergebnissen der Feldforschung. Diese wurde in zwei Bewässerungs-Schemes durchgeführt: New Halfa Scheme in Ostsudan und Gendettu Scheme im Norden des Landes. Die Ergebnisse dieser Studie zeigen auf, daß ein umfassender Entwicklungsansatz alle natürlichen Ressourcen einbeziehen muß. Weiterhin dürfen auch die politischen Verhältnisse im Umfeld der Schemes nicht vernachlässigt werden. Das Ergebnis weist besonders auf die Frage hin, in welchem Ausmaß Partizipation anwendbar ist in den bürokratisch organisierten Bewässerungs-Systemen in Ländern mit ähnlichen Bedingungen. Es konnte festgestellt werden, daß auch die sozioökonomische Dimension beachtet werden muß, wenn die Effizienz der Bewässerung betrachtet wird, d.h. Produktivität und Rentabilität müssen in die Kalkulationen miteinbezogen werden. In diesem Zusammenhang ist es von von äußerster Wichtigkeit, der Modernisierung entsprechender Technologien und der Einbeziehung unterstützender Institutionen große Bedeutung zukommen zu lassen. Die zentrale Schlußfolgerung dieser Studie ist also, daß die Effizienz der Wassernutzung auch die gleichzeitige effiziente Nutzung anderer Ressourcen und Inputs, die von zuliefernden Institutionen zur Verfügung gestellt werden, erfordert. Zusätzlich ist anzumerken, daß das Nichtvorhandensein von Pächter-Partizipation und die Vorherrschaft der Interessen der Scheme-Verwaltung, als Repräsentanten des Staates, der Effizienz entgegenwirken, das heißt, daß sich die Effizienz der Wassernutzer und die des Staates diametral gegenüberstehen. Besonders hervorgehoben werden muß die mangelnde Kommunikation zwischen den verschiedenen Beteiligten der Schemes. Dieser Punkt führt die Aufmerksamkeit direkt zur Rolle der Bauernorganisationen als Verbindung zwischen den Wassernutzern und dem Scheme Management. Die Schlussfolgerung, die aus dieser Analyse gezogen werden kann, ist, daß die Bauernorganisationen ihre Aufgaben unabhängig wahrnehmen müssen. Schließlich betont die Studie, daß zur Erreichung der Ziele, die mit der Erhebung von Bewässerungsgebühren verbunden sind, gleichzeitig instutionelle Veränderungen erforderlich sind.

Univ., Diss.--Kassel, 2007.

Zugl.: Regensburg, Universiẗat, Diss., 2008.

Der intersektorale Wasserkonflikt zwischen urbaner und agrarischer Wassernutzung in Hyderabad und die Konkurrenz zwischen den Bedürfnissen der Stadt und den Ansprüchen der Landwirtschaft werden verschärft durch willkürliche Verteilungspraktiken, die den offiziellen Zuteilungsrichtlinien oft widersprechen. Übersetzt in die Sprache von Ostrom, gilt die vorliegende Untersuchung der Kernfrage, warum bestimmte praktizierte Regeln (rules-in-use) fortbestehen, obwohl formale Regeln (rules-in-form) im Bereich der Nutzungsrechte an Wasser vorhanden sind. Die Arbeit versucht dementsprechend zu erklären, wie bestehende Institutionen und Governancestrukturen die Interaktionen beteiligter Akteure und deren Verhalten beeinflussen und wie daraus eine durch Willkür gekennzeichnete Umverteilung erwächst. Knights Verteilungstheorie institutionellen Wandels und sein Ansatz über Machtressourcen vermögen zu erklären, wie menschliche Interaktionen in Zusammenhang mit solchen Konflikten über begrenzte Ressourcen zustande kommen. Die Ergebnisse der Arbeit zeigen ebenfalls, welche Wirkungen die Charakteristika verschiedener Gruppen von Wassernutzern und deren spezifische Abhängigkeit von Wasserressourcen auf ihre Fähigkeit zur politischen Einflussnahme ausüben. Solche Ausprägungen von Ressourcenabhängigkeiten bedingen Machtasymmetrien und erhöhen das Ausmaß willkürlicher Umverteilungen von Wasser. Die Untersuchung identifiziert eine Literaturlücke im Bereich der Politik der Wassergovernance, indem sie den Wählereinfluss als Machtressource im Land-Stadt-Konflikt um Wasserressourcen empirisch belegt. Die Arbeit zielt insgesamt darauf, das Erklärungspotential von Eigentumsrechtstheorien zu nutzen und anhand von Wasserkonflikten in Hyderabad ein Beispiel zur Anwendbarkeit aktueller Theorien institutionellen Wandels zu geben. / Hyderabad’s inter-sectoral water conflict and competition between the city’s urban needs and the agricultural sector have been fueled by persistent arbitrary water reallocations against the prescribed allocation guidelines. To translate the key question into Ostrom’s language; this study seeks to unravel the persistence of rules-in-use, despite the rules-in-form already in place within the realms of property rights. Ostrom’s Institutional Analysis and Development framework identifies exogenous variables and its influences on the role of institutions which shapes human interaction and decision making processes. It attempts to explain how the existing water-allocation mechanism has propagated the way rules and actors currently interact to influence such arbitrary water re-allocation. Knight’s distributional theory of institutional change and his concept of power resources provide good explanations of human interaction in the context of such conflicts over limited resources. The study results also reveal how the characteristics of water-user groups and its dependence on water resource have the ability to exert political influence over water allocation. Such attributes of resource dependence characterizes power asymmetry, thereby increasing the scale of arbitrary water reallocations. Henceforth, this study addresses the gap in ‘politics of water governance’ in existing literature by empirically deriving ‘political electorate’ as a power resource in rural-urban water contestation. Overall, this study seeks to employ the theoretical explanations of property rights and attempts to provide a case on the applicability of contemporary theories of institutional change by taking the case study of Hyderabad’s water contestation.

Policy makers adopt irrigated agriculture for food security, since irrigation doubles crop production. Therefore, the development of large irrigation systems has a long history in many places worldwide. Although large-scale irrigation schemes play an important role in improving food security, many schemes, especially in Africa, do not yield the expected outcomes. This is related to poor water management, which is generally due to a lack of effective evaluation and monitoring. The objective of this study, therefore, is to propose a new methodology to assess, evaluate and monitor large-scale irrigation systems. Information on irrigation indicators is needed to enable the evaluation of irrigation performance. The evaluation is the first and the most significant step in providing information about how it is performing. After reviewing extensive literature, a list of indicators related to the performance of irrigation, rainwater supply and productivity is suggested. The irrigation efficiency indicators Relative Irrigation Supply (RIS) and Relative Water Supply (RWS) are selected. Potential rainwater supply to crops can be tested based on the Moisture Availability Index (MAI) and the Ratio of Moisture Availability (RMA). Water productivity can be assessed by Crop Yield (Y) and Water Use Efficiency (WUE). However, the central problem facing large-scale irrigation schemes is always the lack of data, which calls for the development of a new method of data acquisition that allows evaluation and monitoring. Remote Sensing (RS) technology makes it possible to retrieve data across large areas. Two different approaches via RS, the Normalized Difference Vegetation Index (NDVI) and Actual Evapotranspiration (ETa), can be utilized for monitoring. The well-known Vegetation Condition Index (VCI), derived from the NDVI, is modified (MVCI) to allow a qualitative spatio-temporal assessment of irrigation efficiency. MVCI takes into account crop response to water availability, while ETa indicates whether water is used as intended. Furthermore, the assessment of the possible hydrological impact of the irrigation system should be considered in the evaluation and monitoring process. The Sudanese Gezira Scheme of 8,000 square kilometers in the Nile Basin, where performance evaluation and monitoring are absent or poorly conducted, is no exception. This research takes the large-scale irrigation of the Gezira Scheme as a case study, as it is the largest scheme, not only in the Nile Basin but also in the world, under single management. The first long-term historical evaluation of the scheme is conducted for the period 1961–2012 rather than only on a short-time scale as is the common practice. An increase in RIS and RWS values from 1.40 and 1.70 to 2.23 and 2.60, respectively, since the 1993/94 season shows decreasing irrigation efficiency. MAI and RMA for summer crops indicate a promising rainfall contribution to irrigation in July and August. The Gezira Scheme achieves low yield and WUE in comparison to many irrigation schemes of the globe. Low productivity is mainly due to poor distribution and irrigation mismanagement. This is indicated by the 15-year MVCI spatio-temporal analysis, which shows that the northern part of the scheme experiences characteristic drought during the summer crop season. Although MVCI can be considered a monitoring tool, the index does not deduct the soil water content, and water could be wasted and available in other ways (e.g. water depressions). Spatio-temporal information for ETa is required to better quantify water depletion and establish links between land use and water allocation. However, several RS models have been developed for estimating ETa. Thus, improving the understanding of performance of such models in arid climates, as well as large-scale irrigation schemes, is taken into account in this study. Four different models based on the energy balance method, the Surface Energy Balance Algorithm for Land (SEBAL), Mapping EvapoTranspiration at High Resolution with Internalized Calibration (METRIC™), Simplified Surface Energy Balance (SSEB) and MOD16 ET are applied in order to determine the optimal approach for obtaining ETa. Outputs from these models are compared to actual water balance (WB) estimates during the 2004/05 season at field scale. Several statistical measures are evaluated, and a score is given for each model in order to select the best-performing model. Based on ranking criteria, SSEB gives the best performance and is seen as a suitable operational ETa model for the scheme. SSEB subsequently is applied for summer and winter crop seasons for the period 2000–2014. Unfortunately, one of the limitations faced in the current research is the absence of validation data on a regional scale. Therefore, the assessment focuses on spatial distribution and trends rather than absolute values. As with the MVCI distribution, the seasonal ETa for the Gezira Scheme is higher in the southern and central parts than in the northern part. This confirms the robustness of the developed MVCI. To avoid using absolute values of ETa, the ratio of ETa from agricultural areas (ETagr) to the total evapotranspiration (ET) from the scheme (ETsum) is calculated. The ETagr/ETsum ratio shows a descending trend over recent years, indicating that the water is available but not being utilized for agricultural production. This study shows that SSEB is also useful for identifying the location of water losses on a daily basis. Around 80 channels are identified as having leakage problems for the 2013/14 crop season. Such information is very useful for reducing losses at the scheme. In addition, Rainwater Harvesting (WH) is addressed and found to be applicable as an alternative solution for accounting for rainfall in irrigation. It is seen that these management scenarios could save water and increase the overall efficiency of the scheme. It is possible to save 68 million cubic meters of water per year when the overall irrigation efficiency of the scheme is improved by only 1%. A level of efficiency of 75% is predicted from the proposed management scenarios, which could save about 2.6 billion cubic meters of water per year. In conclusion, the present study has developed an innovative method of identifying the problems of large-scale schemes as well as proposing management scenarios to enhance irrigation water management practice. Improved agricultural water management in terms of crop, water and land management can increase food production, thereby alleviating poverty and hunger in an environmentally sustainable manner.

Policy makers adopt irrigated agriculture for food security, since irrigation doubles crop production. Therefore, the development of large irrigation systems has a long history in many places worldwide. Although large-scale irrigation schemes play an important role in improving food security, many schemes, especially in Africa, do not yield the expected outcomes. This is related to poor water management, which is generally due to a lack of effective evaluation and monitoring. The objective of this study, therefore, is to propose a new methodology to assess, evaluate and monitor large-scale irrigation systems. Information on irrigation indicators is needed to enable the evaluation of irrigation performance. The evaluation is the first and the most significant step in providing information about how it is performing. After reviewing extensive literature, a list of indicators related to the performance of irrigation, rainwater supply and productivity is suggested. The irrigation efficiency indicators Relative Irrigation Supply (RIS) and Relative Water Supply (RWS) are selected. Potential rainwater supply to crops can be tested based on the Moisture Availability Index (MAI) and the Ratio of Moisture Availability (RMA). Water productivity can be assessed by Crop Yield (Y) and Water Use Efficiency (WUE). However, the central problem facing large-scale irrigation schemes is always the lack of data, which calls for the development of a new method of data acquisition that allows evaluation and monitoring. Remote Sensing (RS) technology makes it possible to retrieve data across large areas. Two different approaches via RS, the Normalized Difference Vegetation Index (NDVI) and Actual Evapotranspiration (ETa), can be utilized for monitoring. The well-known Vegetation Condition Index (VCI), derived from the NDVI, is modified (MVCI) to allow a qualitative spatio-temporal assessment of irrigation efficiency. MVCI takes into account crop response to water availability, while ETa indicates whether water is used as intended. Furthermore, the assessment of the possible hydrological impact of the irrigation system should be considered in the evaluation and monitoring process. The Sudanese Gezira Scheme of 8,000 square kilometers in the Nile Basin, where performance evaluation and monitoring are absent or poorly conducted, is no exception. This research takes the large-scale irrigation of the Gezira Scheme as a case study, as it is the largest scheme, not only in the Nile Basin but also in the world, under single management. The first long-term historical evaluation of the scheme is conducted for the period 1961–2012 rather than only on a short-time scale as is the common practice. An increase in RIS and RWS values from 1.40 and 1.70 to 2.23 and 2.60, respectively, since the 1993/94 season shows decreasing irrigation efficiency. MAI and RMA for summer crops indicate a promising rainfall contribution to irrigation in July and August. The Gezira Scheme achieves low yield and WUE in comparison to many irrigation schemes of the globe. Low productivity is mainly due to poor distribution and irrigation mismanagement. This is indicated by the 15-year MVCI spatio-temporal analysis, which shows that the northern part of the scheme experiences characteristic drought during the summer crop season. Although MVCI can be considered a monitoring tool, the index does not deduct the soil water content, and water could be wasted and available in other ways (e.g. water depressions). Spatio-temporal information for ETa is required to better quantify water depletion and establish links between land use and water allocation. However, several RS models have been developed for estimating ETa. Thus, improving the understanding of performance of such models in arid climates, as well as large-scale irrigation schemes, is taken into account in this study. Four different models based on the energy balance method, the Surface Energy Balance Algorithm for Land (SEBAL), Mapping EvapoTranspiration at High Resolution with Internalized Calibration (METRIC™), Simplified Surface Energy Balance (SSEB) and MOD16 ET are applied in order to determine the optimal approach for obtaining ETa. Outputs from these models are compared to actual water balance (WB) estimates during the 2004/05 season at field scale. Several statistical measures are evaluated, and a score is given for each model in order to select the best-performing model. Based on ranking criteria, SSEB gives the best performance and is seen as a suitable operational ETa model for the scheme. SSEB subsequently is applied for summer and winter crop seasons for the period 2000–2014. Unfortunately, one of the limitations faced in the current research is the absence of validation data on a regional scale. Therefore, the assessment focuses on spatial distribution and trends rather than absolute values. As with the MVCI distribution, the seasonal ETa for the Gezira Scheme is higher in the southern and central parts than in the northern part. This confirms the robustness of the developed MVCI. To avoid using absolute values of ETa, the ratio of ETa from agricultural areas (ETagr) to the total evapotranspiration (ET) from the scheme (ETsum) is calculated. The ETagr/ETsum ratio shows a descending trend over recent years, indicating that the water is available but not being utilized for agricultural production. This study shows that SSEB is also useful for identifying the location of water losses on a daily basis. Around 80 channels are identified as having leakage problems for the 2013/14 crop season. Such information is very useful for reducing losses at the scheme. In addition, Rainwater Harvesting (WH) is addressed and found to be applicable as an alternative solution for accounting for rainfall in irrigation. It is seen that these management scenarios could save water and increase the overall efficiency of the scheme. It is possible to save 68 million cubic meters of water per year when the overall irrigation efficiency of the scheme is improved by only 1%. A level of efficiency of 75% is predicted from the proposed management scenarios, which could save about 2.6 billion cubic meters of water per year. In conclusion, the present study has developed an innovative method of identifying the problems of large-scale schemes as well as proposing management scenarios to enhance irrigation water management practice. Improved agricultural water management in terms of crop, water and land management can increase food production, thereby alleviating poverty and hunger in an environmentally sustainable manner.