500 Naturwissenschaften und Mathematik
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- Fakultät 12 / Institut für Technologie und Ressourcenmanagement in den Tropen und Subtropen (28)
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- Fakultät 02 / Cologne Institute of Conservation Sciences (1)
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In the Mesoamerican forest Selva Maya, multiple driving forces create an imbalance in the sensitive human-nature relation and demand for innovative management strategies for its re-establishment. Within the Guatemalan Maya Biosphere Reserve (MBR), core areas are under strict protective legislation and agricultural activity is permitted only within a bordering buffer zone (BZ), which covers great part of the Guatemalan department Petén. Here, the implementation of agroecological practices by multiple stakeholders aims at tackling the principle driving forces of environmental degradation and thus at reducing the pressure on Central America’s largest tropical forest area. Since 2011, the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) has assisted local stakeholders by carrying out the project “Conservation and sustainable use of the Selva Maya”. This project has offered technical support, cooperated with national institutions, and assisted multiple target groups to nudge agroecological transitions at the household and community level. As the establishment of agroecological systems face main obstacles stemming from the socio-ecological setting of the respective area, the following work presents a context specific analysis for the adaption of established strategies in the MBR BZ. Therefore, it raises the following research questions: What are the current properties of the socio-ecological system that describes the BZ? How has the GIZ’s project nudged and guided agroecological transitions? Which factors have favored or limited the turn to agroecological farming? And finally: Which recommendations derive for the navigation of agroecological transitions? The overall research approach is orientated on the framework of ecosystem stewardship1 and incorporates elements of system theory and resilience science. The framework has been adapted by combining two approaches on different management levels. The social-ecological system approach2 is used to describe the socio-ecological system of the BZ, while the evaluation of the pilot groups‘ AESs follows the Mexican MESMIS3 approach for sustainability assessments. By the integration of both approaches, it is revealed that the socio-economic context impedes or hinders the implementation of agroecological strategies for the majority of farmers. The application of the MESMIS framework has revealed that the installed monitoring mechanism is dysfunctional. Findings further indicate that there is potential for transitions of individual AESs, but they demand investments and support with the current circumstances of reducing farmers’ vulnerability. The rapidly decreasing social and environmental conditions for family farmers in the BZ are most likely not addressed by solutions that the agroecological approach tackles. Recommendations for the immediate improvement of the strategy include adjustments of the project’s proceedings as well as fundamental changes in conservation paradigm and governance to maintain the necessary functionality of the socio-ecological system.
Die vorliegende Masterarbeit behandelt die Bewertung der eingegangenen Unternehmensrisiken im Rahmen der Lebensversicherung und die hiervon abgeleiteten Auswirkungen zur Unternehmenssteuerung.
Dabei wird einerseits die Angemessenheit der sog. „Standardformel“ nach Solvency II überprüft, die in den europäischen Mitgliedsstaaten einen weitestgehend einheitlichen Ansatz bei der Bewertung der Risiken von Versicherungsunternehmen verwendet. Andererseits werden unter ökonomischen Überlegungen versicherungsmathematische Methoden vorgestellt, wie ein Lebensversicherer seine Risiken unternehmensindividueller ermitteln und damit seinen tatsächlichen Risikokapitalbedarf bestimmen kann.
Zur Quantifizierung der Ergebnisse werden die Berechnungsvorgaben der Standardformel für ausgewählte Risikomodule nachgebildet und mit den in dieser Arbeit vorgestellten unternehmensindividuellen Berechnungen verglichen und analysiert. Es zeigt sich, dass trotz der Komplexität des Solvency II-Modells eine noch differenziertere Herangehensweise notwendig ist, damit ein einzelnes Unternehmen seine Risiken adäquat und möglichst individuell bestimmen kann. Zur Gewährleistung einer nicht bestandsgefährdenden Unternehmensfortführung müssen die Versicherungsunternehmen bei Betrachtung ihrer Risiken mithilfe des EU-weiten Aufsichtssystems Solvency II in der Lage sein, die korrekten Rückschlüsse zur Unternehmenssteuerung zu ziehen. Die in dieser Arbeit vorgestellten versicherungsmathematischen Ansätze können dabei den Prozess zur unternehmenseigenen Risiko- und Solvabilitätsbeurteilung (ORSA) unterstützen.
Due to the global phenomenon of climate change the region of Mara Siana is projected to increasingly face extreme weather events that particularly comprise prolonged droughts and
heavier rainfalls. To be able to adequately adapt to these changing circumstances and maintain their livelihoods communities need to build respective capacities. As the main objective, this research aims at determining landowners’ climate change adaptative capacity (CCAC) across different villages in Mara Siana. Accordingly, a semi-quantitative approach was carried out including qualitative interviews and the subsequent quantitative calculation of CCAC based on a multidimensional indicator set and a respective coding
system. In addition to predominantly positive results of socio-cultural characteristics and the quality of natural resources, this work reveals clear weaknesses and potential for improvement in the areas of income security and financial stability, the expansion and resilience of infrastructure, and the relationship between communities and local authorities. Moreover, differences in capacity results are not only identified between the investigated villages as well as between individual households but also systemic disadvantage in capacity building affecting female landowners and community members can be indicated from the obtained interview data. Therefore, this research gives concrete recommendations for the implementation and verification of suitable adaptive measures that are particularly tailored for the improvement of low-performance indicators while following a gendertransformative approach and thus hold the potential to increase CCAC in the long-term.
The increase in greenhouse gas emissions, mainly due to the burning of fossil fuels and land use change, has led to changes in the global climate. Agriculture is one of the economic sectors most vulnerable to the impacts generated by climate change. For this reason, the challenge facing humanity today is to develop innovative solutions to address the complexity of agricultural sustainability.
On the other hand, sugarcane is one of the crops that emits the most pollutants into the atmosphere, mainly due to the burning of sugarcane before and after harvesting. Most of these atmospheric pollutants are precursors of climate change and have an impact on the health and quality of life of communities. Moreover, this agricultural practice causes the gradual deterioration of the soil, directly affecting sugarcane production. Consequently, several sugarcane-producing countries have established regulations or dispositions to eliminate this agricultural practice, and one option to eliminate it is the mechanization of harvesting. However, its implementation implies social, environmental, and economic impacts that must be analyzed systemically to avoid potential failures during the technological transition process. It is for this reason that this research, through the MICMAC method, focused on identifying the variables associated with the reduction of sugarcane burning in Campos dos Goytacazes and Tamasopo, to subsequently analyze their direct and indirect interrelationship, and, thus, determine the opportunities and limitations of each locality for the reduction of sugarcane burning.
Through this analysis, it became evident that although the technological transition is an imminent step for the sustainability of sugarcane cultivation, certain factors such as legislation, technological innovation, and the perception of the stakeholders regarding the consequences of sugarcane burning, is what defines in the study sites the speed and subsequent success of this process of change towards green harvesting.
Aim: European cities are facing heighten hydrological risks as a result of climate change at the same time as ecological degradation has reduced the environmental capacity to absorb and regulate such fluctuations. Climate forecasts predict more intense convective rainfall and winter flood events in the Wupper Basin in Germany, against a background trend of reduced mean rainfall during the summer months. On 14 July 2021 intense convective rainfall fell at points across Western Germany and led to flash floods in the Wupper Basin, many sites were inundated and the Wupper and Dhünn rivers rose to new record highs. Green-blue infrastructure offers strategies to reduce the impacts of hazards at the same time as providing a range of co-benefits. A study was undertaken to find which green-blue interventions will be most effective at reducing the impacts of hydrometeorological hazards for a study area in the west of the Wupper basin. Furthermore, as landscape features are highly influential in hydrology, the study sought to establish which sites within the landscape can provide maximum results from green-blue interventions, with a minimum of change to current land uses.
Region: Europe, peri-urban and rural, undulating, low mountainous landscapes
Methods: Literature findings on observed and projected climate data are summarised and long-term rainfall data from the study area is analysed to confirm rainfall trends. A state-of-the-art review is conducted and summarised to form a toolbox of potential interventions. The most recent hazardous hydrometeorological event is analysed to inform the locational priorities of potential interventions. Landscape features that have the most influence on basin hydrology are identified from the literature. These sites are paired with green-blue interventions that are shown to have the highest potential impact on interception, infiltration, runoff and flooding. A series of spatial analyses are carried out to produce maps detailing location and intervention with high potential to reduce the impact of hydrometeorological hazards in the study area. All of the evidence gathered from the literature analysis is combined in an implementation guide for green-blue interventions in the Wupper Basin.
Results: The hazards caused by the hydrometeorological extremes of flooding and drought are addressed or minimised through the green-blue interventions that increase interception and infiltration and reduce runoff and flooding. Priority locations are identified as the riparian zone with slope ≤15%, hilltop, lower slope and toe slope, all locations with a slope ≥30% and areas with a high topographic wetness index (TWI). A series of spatial analyses were carried out and suggestions made including potential locations for retention or detention areas and ponds, sites for revegetation and potential locations for implementation of shelterbelts/hedgerows, buffer strips, conservation tillage or strip tillage, reduced mowing intensity or frequency and biochar additions. An implementation guide is created that provides a summary of the highest potential green-blue interventions and landscape locations, and a description of the mechanisms involved in addressing the hydrometeorological hazards.
Keywords: Green-blue interventions, hydrometeorological hazard reduction, Wupper Basin hydrology
Mangrove forests have been studied broadly in the recent three decades for their outstanding ability to sequester carbon in the beneath soil and other beneficial ecosystem services. Endeavors to conserve and regenerate mangrove cover are still increasing worldwide as a mechanism to include them in NDCs and carbon markets. Therefore, decision-makers in the private and public sectors require identify possible areas for conservation and restoration prior to blue carbon project investment. Thus, an integral assessment of potential mangrove carbon reservoirs in a landscape scale, considering environmental and socioeconomic factors was performed. This study was aimed to determine areas with the highest blue carbon sequestration potential in the Gulf of Guayaquil through the construction of a Blue Carbon Potential Index (BCPI) based on Spatial Multicriteria Analysis (SMCA). A narrative integrative literature review was employed to select indicators of mangrove carbon sequestration gains and losses. These indicators were pondered following the Analytical Hierarchy Process (AHP) with the judgments of two experts and reclassified in four potential categories based on their thresholds. Since no consensus was achieved in the indicator importance hierarchization, a comparative of equal weighting method and AHP weighting was implemented. The linear combination rule was used to integrate these factors into a unique-scaled index supported by a geographic Information System (GIS). The results showed that 15.82% and 16.21% of the study area belonged to high and moderate potential of blue carbon sequestration respectively. Moreover, no significant differences were found between the two weighting methods applied. The BCPI provides a comprehensive understanding of spatial distribution of blue carbon potential reservoirs and grants a quantification of this potential to prioritize conservation and restoration areas.
Carbon Sequestration under different land uses and soils in the State of Quintana Roo, Mexico
(2017)
Rising in global temperature is evidently related to atmospheric carbon dioxide (CO2) and methane (CH4) concentrations; this has become an environmental problem. The use of renewable energy, the development of eco-friendly merchandise and the enforcement of biomass management have been proposed to mitigate the issue. In the ecosphere, the pedosphere stores 1,500 to 2,500 PgC, which is four times more than the carbon stored in biomass; hence, it is very important to carry out soil carbon studies because of more long-term stability of such storage. In the study, soil carbon quantification was applied to the entire state of Quintana Roo, using a purpose oriented sampling, to observe the dynamic between land uses and soils, relating all relevant characteristics and properties of the landscape. To study the carbon content stored in soils, total carbon was estimated through loss-on-ignition, organic carbon by Walkley-Black method and inorganic carbon by calcium carbonate determination. The result portrays that the coastal dune vegetation-Arenosol (1,256 Mg C ha-1) is the combination with the highest soil carbon density, while Leptosol is the soil type with the highest storage capacity (852 MtC). Consequently, the soil carbon storage not only relates to soil properties but also associates with the surface area occupied by the specific soil type. In addition, the characteristics of the landscape play an important role in the storage of soil carbon. Due to that, soil carbon storage can be explained by biogeomorphoedaphic factors.
Due to its location at the south-west coast of Ireland County (Co.) Cork is frequently affected by post tropical cyclones (PTCs). There have been several records of these post hurricanes in the past with the last severe PTC being Hurricane Ophelia in 2017. It caused severe disruption in the whole country, especially in Co. Cork with several thousand people without water, power and mobile service for up to 10 days and thousands of uprooted trees which blocked roads. PTCs, like Ophelia, will become more frequent under climate change conditions due to warmer sea surface temperatures and decreased vertical wind shear. Hence, hurricanes can reach northern latitudes more easily and have a higher chance of making landfall in Co. Cork. This thesis assesses the risk perception towards natural hazards (NHs) and the perception of the risk communication of hurricane Ophelia by the citizens of Co. Cork and suggests improvements in communication based on the people’s perception. This was achieved by conducting a standardised survey to analyse the perception. The risk communication chain, its content and media involved were evaluated with interviews with professionals involved in risk management in Ireland. Improvement suggestions were extracted of the survey and the expert interviews as well and have been ranked by the participating experts according to their importance. The people of Co. Cork are not overly concerned about being affected by NHs. The three hazards they feel threatened by most, after Ophelia hit the country, are storms, river floodings and hurricanes. Before Ophelia made landfall, they only ranked hurricanes in the 8th place (out of 8). Ergo, after experiencing Ophelia people are much more aware of hurricane risk in Ireland. People were very satisfied with the information they received during Ophelia. The improvements they wished for are: 1) information on how to deal with and how to prepare for impacts of the storm, 2) the impacts that can be expected locally and 3) information where to go to in case of severe impact to property. These are mostly in line with the improvements the experts ranked as most important for Cork. Experts voted the suggestion to include information on behavioural advice into risk communication before the NH hits and advice on how to organise for impacts afterwards as their number one priority. Their second rank is to have education and training for the citizens in Cork. On third place they voted for a change to impact forecasting. Even there are no central buildings or shelters available in Co. Cork, this improvement suggestion was only voted on rank 13 by the experts (out of 14). Having a participatory approach in risk communication can overcome the discrepancies between the wishes of the population and the ones of the experts and would lead to a better understanding of all stakeholders involved in risk communication and can reduce vulnerability of the people in Co. Cork to the impacts of NHs. The implementation of these activities would be in line with best practice examples and would support the guidelines of the Irish Framework for Major Emergency Management.
Policy measures are essential tools for the transition from fossil fuels to renewable energy sources in the electricity generation. Feed-in tariffs (FITs) are the most used policy for support of renewable technologies globally. Nevertheless, Ecuador phased-out FITs in 2016 and adopted auctions in 2015. Ecuador’s implementation of auctions reflects an approach with little relation to practices in other countries and without a technology-specific design. On the other hand, Germany demonstrates a long trajectory in policy-making with vast experience in FITs. Moreover, in 2017 Germany adopted auctions as the official policy to support renewable projects with a scope larger than 750 kW. However, FITs are still in use and complement auctions.
This thesis analyses and compares the country-specific contexts where these policies are implemented through the lens of a multi-level perspective framework. As a result, the most important success factors in Germany have been identified: long-term planning, institutional continuity, legislative stability and principally an actively participating society, which is environmentally aware. Obstacles for the transition in Ecuador are institutional discontinuity, legislative inconsistency, the lack of long-term planning and absence of society as actors of the transition. Due to Germany’s pioneering role plus the successful growth of renewable sources during the last twenty years, their policy implementations appear desirable to adopt in other contexts. Therefore, a prospective transferability of the auction policy from Germany to Ecuador is additionally analyzed.
Water risk assessment is becoming an essential part of any decision-making process in the business sector. In the world where freshwater resources are becoming scarcer, water risks are growing and causing high costs to businesses. Therefore, numerous frameworks, guidelines, methodologies, tools, and other approaches were developed during the last century. Various scholars have appeared to give an economic value or price for environment goods in order to understand trade-offs better. Nowadays, the corporate world tends to use different approaches to convert sustainability management data to the financial language of decision-makers. This study explores the possible ways for a company to measure the costs of water related risks. It examines how to convert water risks to financial risks using a Peruvian agricultural company. The results show, that from all today’s available frameworks, guidelines or tools there is no one commonly accepted and recognised as the best for water risk assessment and monetising. It was learned, that available tools could provide just a simple overview of possible water related risks and calculate their costs in a very general way. The work also highlights the importance of regular and appropriate data collection on the company level in order to be able to assess water risk related costs for the business.