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Ghana ist ein Musterbeispiel dafür, dass ein Entwicklungsland den Weg zu Good Governance schaffen kann. In vielen Studien wird dem Land im afrikanischen Vergleich heute bescheinigt, hier ein Vorreiter zu sein. Dies ist Ausgangslage der vorliegenden Studie, die der Frage nachgeht „Welche Gründe, Muster und Bedingungen führen zur Entstehung von Good Governance?“. Im Zentrum der vorliegenden Studie steht, wie aus der erkenntnisleitenden Fragestellung hervorgeht, eine empirische Untersuchung zur Entstehung von Good Governance und damit ein Transformationsprozess. Dieser wird bewusst über einen sehr langen Zeitraum (über ein halbes Jahrhundert) untersucht, um auch langfristige Entwicklungen einbeziehen zu können. Die Studie wird mit Hilfe eines „Mixed-Methods-Ansatzes“ sowohl unter Rückgriff auf quantitative als auch auf qualitative Methoden durchgeführt, was sich im Rückblick als sehr ertragreich erwiesen hat. Zunächst wird die Qualität der Governance über den gesamten Zeitraum anhand von sechs Indikatoren gemessen. Danach werden qualitativ die Gründe für die Fort- und Rückschritte analysiert. Dabei lassen sich immer wieder Systematiken herausarbeiten, wie zum Beispiel zirkuläre Entwicklungen, die über viele Jahre den Weg hin zu Good Governance verhinderten, bis jeweils Ausbrüche aus den Kreisläufen geschafft werden konnten. Sowohl in der demokratischen und rechtsstaatlichen Entwicklung als auch bezogen auf die Versorgung der Bevölkerung mit öffentlichen Gütern und die wirtschaftliche Entwicklung. Auch wenn die verschiedenen Bereiche von Good Governance zunächst einzeln untersucht werden, so zeigen sich gleichzeitig deutlich die Wechselwirkungen der Komponenten. Zum Beispiel kristallisiert sich klar heraus, dass Rechtsstaatlichkeit sowohl auf die Stabilität politischer Systeme wirkt, als auch auf die wirtschaftliche Entwicklung. Ebenso beeinflussen diese wiederum die Korruption. Ähnliche Verknüpfungen lassen sich auch bei allen anderen Bereichen nachvollziehen. Die Entwicklung eines Landes kann also nur unter Berücksichtigung eines komplexen Governance-Systems verstanden und erklärt werden. Dabei können die Wechselwirkungen entweder konstruktiv oder destruktiv sein. Die Verflechtungen der einzelnen Bereiche werden in einem Negativ- und dann in einem Positiv-Szenario festgehalten. Diese Idealtypen-Bildung spitzt die Erkenntnisse der vorliegenden Arbeit zu und dient dem analytischen Verständnis der untersuchten Prozesse. Die Untersuchung zeigt, wie Good Governance über das Zusammenspiel verschiedener Faktoren entstehen kann und dass es wissenschaftlich sehr ertragreich ist, Transformationsforschung auf ein komplexes Governance-System auszuweiten. Hierbei werden die vielen empirisch erarbeiteten Ergebnisse zu den einzelnen Transformationen zu komplexen, in sich greifenden Gesamtszenarien zusammengeführt. Da es bisher keine explizite Good Governance-Transformationsforschung gab, wurde hiermit ein erster Schritt in diese Richtung getan. Es wird darüber hinaus deutlich, dass eine Transformation zu Good Governance nicht durch eine kurzfristige Veränderung der Rahmenbedingungen zu erreichen ist. Es geht um kulturelle Veränderungen, um Lernprozesse, um langfristige Entwicklungen, die in der Studie am Beispiel Ghana analysiert werden. In vielen vorangegangenen Transformationsstudien wurde diese zeitliche Komponente vernachlässigt. Ghana hat bereits viele Schritte getan, um einen Weg in die Zukunft und zu Good Governance zu finden. Die Untersuchung dieser Schritte ist Kern der vorliegenden Arbeit. Der Weg Ghanas ist jedoch noch nicht abgeschlossen.
Groundwater is critical in supporting current and future reliable water supply throughout Africa. Although continental maps of groundwater storage and recharge have been developed, we currently lack a clear understanding on how the controls on groundwater recharge vary across the entire continent. Reviewing the existing literature, we synthesize information on reported groundwater recharge controls in Africa. We find that 15 out of 22 of these controls can be characterised using global datasets. We develop 11 descriptors of climatic, topographic, vegetation, soil and geologic properties using global datasets, to characterise groundwater recharge controls in Africa. These descriptors cluster Africa into 15 Recharge Landscape Units for which we expect recharge controls to be similar. Over 80% of the continents land area is organized by just nine of these units. We also find that aggregating the Units by similarity into four broader Recharge Landscapes (Desert, Dryland, Wet tropical and Wet tropical forest) provides a suitable level of landscape organisation to explain differences in ground-based long-term mean annual recharge and recharge ratio (annual recharge / annual precipitation) estimates. Furthermore, wetter Recharge Landscapes are more efficient in converting rainfall to recharge than drier Recharge Landscapes as well as having higher annual recharge rates. In Dryland Recharge Landscapes, we found that annual recharge rates largely varied according to mean annual precipitation, whereas recharge ratio estimates increase with increasing monthly variability in P-PET. However, we were unable to explain why ground based estimates of recharge signatures vary across other Recharge Landscapes, in which there are fewer ground based recharge estimates, using global datasets alone. Even in dryland regions, there is still considerable unexplained variability in the estimates of annual recharge and recharge ratio, stressing the limitations of global datasets for investigating ground-based information.
Die nachfolgende Länderstudie ist während eines längeren Arbeitsaufenthaltes im Rahmen der internationalen Zusammenarbeit in Kamerun entstanden. Mit ihr versuchen wir, unsere persönlichen Eindrücke und täglichen Beobachtungen in einem Land zu verarbeiten, in dem offenbar alle Hoffnung darauf beruht, dass der alternde Staatspräsident Paul Biya seinen Abschied von der politischen Bühne nimmt und damit ein autokratisches, korruptes Regime sein Ende findet. Diese Hoffnung scheint mit der Erwartung von Francis Fukuyama verbunden zu werden, der 1992 nach dem Zusammenbruch des Sowjet-Imperiums das „Ende der Geschichte“ erklärte, in der Überzeugung, dass das demokratische Gesellschaftsmodell bald überall Einzug halten würde. Bekanntlich hat sich diese Erwartung als zu optimistisch erwiesen. Mit unserer Untersuchung versuchen wir aufzuzeigen, warum sich die Hoffnung auf eine gerechtere Gesellschaft trotz langjähriger Bemühungen westlicher Geber um die Stärkung der Zivilgesellschaft und die Dezentralisierung staatlicher Aufgaben auch in Kamerun kaum erfüllen wird. Ein „Ende der Geschichte“ lässt sich auch für die Zeit nach Paul Biya nicht prognostizieren.
Forage supply of savanna grasslands plays a crucial role for local food security and consequently, a reliable monitoring system could help to better manage vital forage resources. To help installing such a monitoring system, we investigated whether in-situ hyperspectral data could be resampled to match the spectral resolution of multi- and hyperspectral satellites; if the type of sensor affected model transfer; and if spatio-temporal patterns of forage characteristics could be related to environmental drivers. We established models for forage quantity (green biomass) and five forage quality proxies (metabolisable energy, acid/neutral detergent fibre, ash, phosphorus). Hyperspectral resolution of the Hyperion satellite mostly resulted in higher accuracies (i.e. higher R-2, lower RMSE). When applied to satellite data, though, the greater quality of the multispectral Sentinel-2 satellite data leads to more realistic forage maps. By analysing a three-year time series, we found plant phenology and cumulated precipitation to be the most important environmental drivers of forage supply. We conclude that none of the investigated satellites provide optimal conditions for monitoring purposes. Future hyperspectral satellite missions like EnMAP, combining the high information level of Hyperion with the good data quality and resolution of Sentinel-2, will provide the prerequisites for installing a regular monitoring service.
The name Mandela became first inscribed in the annals of African liberation as nothing particularly unusual at the time. The late fifties was an era of trials and detentions in the colonies. The Treason Trial, which took place from 1956 to 1961, was closely followed by those of my generation largely through Drum Magazine.
The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021-2050) and far-term period (2071-2100) with reference to 1976-2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021-2050 and between +131 and +388% during 2071-2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture.
Scenarios have become a key tool for supporting sustainability research on regional and global change. In this study we evaluate four regional scenario assessments: first, to explore a number of research challenges related to sustainability science and, second, to contribute to sustainability research in the specific case studies. The four case studies used commonly applied scenario approaches that are (i) a story and simulation approach with stakeholder participation in the Oum Zessar watershed, Tunisia, (ii) a participatory scenario exploration in the Rwenzori region, Uganda, (iii) a model-based prepolicy study in the Inner Niger Delta, Mali, and (iv) a model coupling-based scenario analysis in upper Thukela basin, South Africa. The scenario assessments are evaluated against a set of known challenges in sustainability science, with each challenge represented by two indicators, complemented by a survey carried out on the perception of the scenario assessments within the case study regions. The results show that all types of scenario assessments address many sustainability challenges, but that the more complex ones based on story and simulation and model coupling are the most comprehensive. The study highlights the need to investigate abrupt system changes as well as governmental and political factors as important sources of uncertainty. For an in-depth analysis of these issues, the use of qualitative approaches and an active engagement of local stakeholders are suggested. Studying ecological thresholds for the regional scale is recommended to support research on regional sustainability. The evaluation of the scenario processes and outcomes by local researchers indicates the most transparent scenario assessments as the most useful. Focused, straightforward, yet iterative scenario assessments can be very relevant by contributing information to selected sustainability problems.
Scenarios have become a key tool for supporting sustainability research on regional and global change. In this study we evaluate four regional scenario assessments: first, to explore a number of research challenges related to sustainability science and, second, to contribute to sustainability research in the specific case studies. The four case studies used commonly applied scenario approaches that are (i) a story and simulation approach with stakeholder participation in the Oum Zessar watershed, Tunisia, (ii) a participatory scenario exploration in the Rwenzori region, Uganda, (iii) a model-based prepolicy study in the Inner Niger Delta, Mali, and (iv) a model coupling-based scenario analysis in upper Thukela basin, South Africa. The scenario assessments are evaluated against a set of known challenges in sustainability science, with each challenge represented by two indicators, complemented by a survey carried out on the perception of the scenario assessments within the case study regions. The results show that all types of scenario assessments address many sustainability challenges, but that the more complex ones based on story and simulation and model coupling are the most comprehensive. The study highlights the need to investigate abrupt system changes as well as governmental and political factors as important sources of uncertainty. For an in-depth analysis of these issues, the use of qualitative approaches and an active engagement of local stakeholders are suggested. Studying ecological thresholds for the regional scale is recommended to support research on regional sustainability. The evaluation of the scenario processes and outcomes by local researchers indicates the most transparent scenario assessments as the most useful. Focused, straightforward, yet iterative scenario assessments can be very relevant by contributing information to selected sustainability problems.
Vor 50 Jahren löste sich Algerien nach langem Kampf endgültig aus dem französischen Kolonialreich. Die anschließend durchgeführten Wirtschaftsreformen konnten das Land aber nicht befrieden, weil sie keine effektive Nutzung der Rente verwirklichten. Bis heute ist die Wirtschaft des Landes wenig diversifiziert und stark von Erdöleinnahmen abhängig. Ist eine exportorientierte Industrialisierung als Lösung der Probleme denkbar?
This cumulative habilitation thesis presents new work on the systematics, paleoecology, and evolution of antelopes and other large mammals, focusing mainly on the late Miocene to Pleistocene terrestrial fossil record of Africa and Arabia. The studies included here range from descriptions of new species to broad-scale analyses of diversification and community evolution in large mammals over millions of years. A uniting theme is the evolution, across both temporal and spatial scales, of the environments and faunas that characterize modern African savannas today. One conclusion of this work is that macroevolutionary changes in large mammals are best characterized at regional (subcontinental to continental) and long-term temporal scales. General views of evolution developed on records that are too restricted in spatial and temporal extent are likely to ascribe too much influence to local or short-lived events. While this distinction in the scale of analysis and interpretation may seem trivial, it is challenging to implement given the geographically and temporally uneven nature of the fossil record, and the difficulties of synthesizing spatially and temporally dispersed datasets. This work attempts to do just that, bringing together primary fossil discoveries from eastern Africa to Arabia, from the Miocene to the Pleistocene, and across a wide range of (mainly large mammal) taxa. The end result is support for hypotheses stressing the impact of both climatic and biotic factors on long-term faunal change, and a more geographically integrated view of evolution in the African fossil record.