Refine
Year of publication
- 2020 (6) (remove)
Document Type
- Master's Thesis (6)
Language
- English (6)
Has Fulltext
- yes (6)
Keywords
Faculty
- Fakultät 12 / Institut für Technologie und Ressourcenmanagement in den Tropen und Subtropen (6) (remove)
Chagas disease is a parasitic infection endemic to America, caused by the protozoan Trypanosoma cruzi and mainly transmitted to humans by contact with insect species of the Triatominae subfamily (Hemiptera). The disease is known to affect disproportionally rural impoverished human communities where it is known to cause premature death and is considered a social and economic burden. The Mexican government has made important progress into the detection, surveillance, treatment, and prevention of the disease in the last decades, however, Chagas disease has also been reported in areas where it had not been previously reported, and there are still barriers for access to treatment. In the state of San Luis Potosi, the disease is more studied in the east, nevertheless, it has been estimated that the reported cases of the entire state have been underestimated. New approaches to detect Chagas risk areas could help prioritize locations for Chagas disease education and prevention programs, detect cases of the disease in a timely manner, and provide access to the necessary treatments. The objective of this study was to identify risk areas for the transmission of Chagas disease in San Luis Potosí using species distribution modelling to estimate vectors and reservoirs’ distributions. To do this, firstly, important vectors and one reservoir species of T. cruzi were identified by reviewing their reported infection rates in literature and the number of times reported in Mexico. Next, species distribution models were calculated for the chosen vector and reservoir species present in the state. The models were done using the Maxent algorithm. Lastly, the resulting distribution models were combined into a risk map by thresholding the model outputs to produce binary predictions and then performing an overlap spatial analysis. Vector species were found to have suitable areas in 36.08% of the state’s territory while areas suitable for both vectors and reservoir were 7.4% of the state’s total area. While this figure may look small at first glance, the analysis suggests that 30% of the rural population and 52% of the urban population of the state are living in an area suitable for vectors and reservoir and therefore at risk. Species distribution modelling can be a powerful tool for identifying human populations at risk of contracting Chagas disease. In the future, including different species of reservoirs into the analysis could help to discover new risk areas in the state.
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.
In 2015, the adoption of the 2030 Agenda for Sustainable Development, including the 17 Sustainable Development Goals (SDGs), and the Paris Agreement provided a basis for considerable optimism for the fight against climate change and efforts to promote sustainable development, but their implementation remains an enormous challenge. Finance, in turn, plays a key role in implementation. This thesis thus seeks to provide new insights into the challenge of implementing the Paris Agreement and the 2030 Agenda by examining pertinent financial flows while taking into considering that making use of thematic overlaps between these two agendas can help to leverage synergies, especially if financial flows take adequate account of these overlaps. Since energy plays an essential role in both the goals of the Paris Agreement and the 2030 Agenda (in SDG 7 and beyond it), this thesis focuses on countries’ energy-related national commitments. Against this background, this thesis investigates the question which role energy plays in the Nationally Determined Contributions (NDCs) under the Paris Agreement and to what extent climate finance is considered in the context of the energy system transition. The key finding is that financial flow for renewable energy and energy efficiency improves globally with an unchanged track of non-renewable energy in the post-NDC period.
This research analyzes the effects that eco-labels have on the demand for organic (Bio) and Fairtrade (FT) food products. The thesis also discusses the individual determinants and motivations behind those effects. The analysis builds on data obtained from a self-programmed and self-conducted survey, with a sample of 869 students from different universities of Cologne, Germany. The Bio/FT preference is measured experimentally by randomly assigning individuals to treatment and control groups. The experiment simulates life decisions using actual pictures and prices of four products: packed and processed spaghetti, fresh tomatoes, packed raw meat, and packed orange juice.
The existence, size, and direction of statistically significant eco-label effects were obtained with two sample tests of proportions. The results prove that the FT label has a positive differential effect on consumer’s demand. The presence of the FT label makes the purchase of this juice 9.1% higher than other juices not labeled as FT. This finding confirms the hypothesis that eco-labels have a positive effect on sustainable consumption. A surprising finding is that the presence of the Bio label lowers the purchase of organic pasta and tomatoes 7.7% and 9.4% respectively. This finding is interesting because it suggests that Bio labels are not driving the demand for sustainable tomatoes or pasta for this population. Regional and cheaper alternatives are preferred by consumers in this cases.
The motivations behind consumer choices of different options were thoroughly analyzed. Binomial logistic regressions and qualitative text analysis show that the variance in the intention to consume eco-labeled food is explained mainly by price concerns and attitudes about value for money, but also by the influence of life partners as shopping referents, and the perceived behavioral controls of time and ability to monitor compliance of label standards, thus trust them.
The final remarks support the use of the Fairtrade eco-label as a market-based instrument to guide sustainable food consumption among young adults in this context, and propose changes that could make the Bio label more attractive for the targeted population. The thesis demonstrates which individual factors should be inevitably considered when implementing labeling to foster sustainable consumption. Hence, it is useful for evaluations of public and private certification schemes, and for companies that support sustainable food markets. Projects looking to understand and drive sustainable production and consumption decisions should consider this reading.
Habitat loss due to land use and land cover change (LUCC) has been identified as the main cause of global environmental change, responsible for biodiversity decline and the deterioration of ecological processes. Habitat loss and fragmentation have been driven by
processes of LUCC such as deforestation, agricultural expansion and intensification, urbanization, and globalization. The objective of this research was to determine the effects of LUCC on the process of habitat loss and the patterns of fragmentation in the surrounding landscape of the Pacuare Reserve (PR) in the Caribbean lowlands of Costa Rica. The PR is a protected area of 800 ha surrounded by an agricultural landscape with a history of over 150 years of bananas monocultures. Landsat satellite images from 1978 to 2020 were used to conduct a temporal analysis of LUCC around the PR. Patterns of change were explored using landscape metrics from the land classification images. To explore potential connectivity routes, the least cost path analysis was used to connect the PR to other protected areas. Overall, forest cover decreased in the study area at a rate of -4.8% per year during the period of 1992-1997. In the year 2001 it reached its lowest cover and then increased at a mean annual rate of 1.6%. A mean overall accuracy of 92% was obtained for the land classification process. A clear fragmentation process was observed, as shown by a decreased in forest mean patch area and largest patch index and by the increase in patch density. Although forest cover increased in the last decade, fragmentation metrics suggest this recover happened in a spatially scattered manner, due to agricultural land abandonment. Connectivity maps showed the importance of forest fragments and of the already established biological corridors for the movement of species to and from the PR, however it also evidenced the lack of connectivity between the coastal forest fragments and further inside the country located protected areas, as well as the need to promote reforestation projects, particularly between fragments of the corridors identified.
Urbanization processes are one of the main factors for habitat loss and fragmentation, driving global biodiversity loss and species extinction. The neotropical Atlantic forest in Brazil is considered a global key biodiversity hotspot and used to be one of the most extensive forests of the Americas. Due to substantial deforestation over centuries, its landscape was transformed into a mosaic of small forest fragments surrounded by a predominantly agricultural matrix. Urban expansion and rural urbanization have created peri-urban zones, which still can harbor natural habitat remnants,
contributing to biological diversity and thus providing essential ecosystem services to urban and rural areas. The maintenance of such ecosystem services requires an understanding of the ecological processes in the ecosystem. A prerequisite for such an in-depth insight is the quantification of the underlying ecosystem functions. The ecosystem function pest control, a trophic interaction between insectivorous birds and herbivorous arthropods, was quantified in an empirical study using artificial caterpillars as prey models. This technique allows the identification of predator groups and the assessment of their predation rates. A total of 888 plasticine caterpillars were distributed at eight sites in secondary forest fragments surrounding the university campus of the federal university of São Carlos (UFScar) in peri-urban Sorocaba, southeastern Brazil. In sixteen point counts, 72 insect-eating birds, belonging to 19 species, were identified as possible artificial caterpillar attackers. Local habitat variables were measured to describe the forest vegetation structure and the landscape context. The study aimed to assess which structural components of the
forest fragments, together with the recorded bird community variables (abundance, richness, αdiversity), best explain the estimated predation rates by birds. The mean predation rate for birds was 8.25 ± 6.3 % for a reference period of eight days, representing the first quantification of the ecosystem function pest control for the study area. The three treatments of caterpillar placement heights (ground, stem: 0.5 -1.0 m, leaf: 1.5 - 2.0 m) were the best and only estimator to explain bird
predation rates. The little dense understory and ground vegetation might have facilitated the accessibility of artificial caterpillars, especially for carnivorous arthropods and birds. The detected contrast in their foraging and predation patterns suggests that arthropods and birds complement each other in their function of pest control. Bird predation rates were found to be negatively related to the vegetation structure. Thus, more open habitats, with less understory and low tree density, but high canopy cover and including dead trees were correlated with the highest predation rates and also exhibited more specialized forest-dependent bird species. This study confirms the importance of the maintenance of forest fragments in peri-urban areas, even if they are small, to preserve forest-associated birds, to contribute to the biological diversity on a broader scale, and to prevent the loss of ecosystem functions and services, mitigating some of the adverse effects of urbanization. Further investigation of the effect among the three treatments of caterpillar
placement on the predation rates is encouraged, including comparative studies among different habitat types. For future studies, it is recommended to model the avian community variables with the vegetation structure measures to predict habitat preferences of insectivorous birds. Therefore, the sampling of more units and on a bigger scale, including over a more extended period, is necessary to improve the robustness of the results, which could provide the basis for a monetary analysis of the ecosystem service pest control by birds.