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Now showing items 71-80 of 251
Dissertation
Challenges to ecosystem services of sustainable agriculture in West Africa
(2020)
Food security is still sub-optimal in many parts of West Africa calling for more efficient agricultural practices in mitigating food insecurity. Some of the problems faced in West African agricultural systems are bottlenecks in ruminant livestock supply, inefficiency in commercial poultry production, and loss of arthropod diversity. These issues require proper integration of farming systems, demand the closing of nutrient cycles, need diversi cation of production, and require enhancement of ecosystem services. To ...
Dissertation
Entwicklung einer Robotik-Lösung zur Schneckenbekämpfung in der Landwirtschaft
(2020)
Schnecken sind bedeutende Schädlinge in der Landwirtschaft. Die Ausbringung von Schneckenkorn zur Schneckenbekämpfung als Verfahren nach dem Stand der Technik hat jedoch erhebliche Nachteile. Der Erfolg ist abhängig von der vorherrschenden Witterung und damit unsicher, zudem schadet es auch Nützlingen. Eine Robotik-Lösung zu Schneckenbekämpfung arbeitet wetterunabhängig und ist in der Lage, zwischen Schädlingen und Nützlingen zu unterscheiden.
Durch einen Feldversuch konnte gezeigt werden, dass Überfahrten eines ...
Dissertation
Development of Energy use Profiles, Reduction Concepts, and Implementation of Renewable Energies in the Central Ugandan Pineapple Processing Chains
(2020-02)
Pineapples, like all fruits, are highly perishable and require either immediate consumption or preservation. To make them more stable and add value, four major processing methods are being employed in Uganda, i.e. drying, munaanansi (local drink), wine, and juice making. Energy is one of the main inputs required to achieve any of the processing methods. The aim of this research was to develop energy use profiles, gain insights into energy use reduction options, and to evaluate the applicability of renewable energies ...
Dissertation
The potential of UAV-based remote sensing for the prediction of aboveground biomass and N fixation in legume-grass mixtures
(2020-07)
The world population is growing steadily and with it the demand for meat and animal protein. A major source of feed for livestock is grassland, which serves as high quality and protein rich forage. In addition to permanent grassland, temporary grassland is a valuable crop rotation element, especially in organic farming, since legumes in legume-grass mixtures can fix atmospheric nitrogen (NFix). To further increase the intensification in agriculture, reliable non-destructive measurement techniques are needed as an ...
Dissertation
Interactions of organic amendments, pea (Pisum sativum L.) growth, arbuscular mycorrhizal fungi and other soil microorganisms
(2017-07-25)
Microbial decomposition of organic substances in soil is a central process for maintaining nutrient cycling, and it can be affected by the presence of plants, especially by mycorrhizal plants, in different ways. Organic fertilizers maintain soil fertility and increase crop productivity. Less attention has been paid to C-rich organic fertilizers. On the other hand, legumes are the main source of N input in organic farming. However, field peas grown as a sole crop suffer many problems that make the yield low and ...
Dissertation
Impact of sward type, cutting date and conditioning temperature on mass and energy flows in the integrated generation of solid fuel and biogas from semi-natural grassland
(2011-01-21)
Energy production from biomass and the conservation of ecologically valuable grassland habitats are two important issues of agriculture today. The combination of a bioenergy production, which minimises environmental impacts and competition with food production for land with a conversion of semi-natural grasslands through new utilization alternatives for the biomass, led to the development of the IFBB process. Its basic principle is the separation of biomass into a liquid fraction (press fluid, PF) for the production ...
Dissertation
Effects of plant diversity on bioenergy parameters in grassland biomass
(2013-01-28)
Extensive grassland biomass for bioenergy production has long been subject of scientific research. The possibility of combining nature conservation goals with a profitable management while reducing competition with food production has created a strong interest in this topic. However, the botanical composition will play a key role for solid fuel quality of grassland biomass and will have effects on the combustion process by potentially causing corrosion, emission and slagging. On the other hand, botanical composition ...
Dissertation
Alley cropping of willows and grassland for bioenergy provision: productivity, tree-crop interactions and energy balance
(2015-08-12)
The demand for biomass for bioenergy has increased rapidly in industrialized countries in the recent years. Biogenic energy carriers are known to reduce CO2 emissions. However, the resource-inefficient production of biomass often caused negative impacts on the environment, e.g. biodiversity losses, nitrate leaching, and erosion. The detrimental effects evolved mainly from annual crops. Therefore, the aim of modern bioenergy cropping systems is to combine yield stability and environmental benefits by the establishment ...
Dissertation
Urban Grass and Grass-Leaf Litter Mixtures as Source for Bioenergy Recovery
(2016-03-02)
Städtische Biomassen der Grünflächen bilden eine potentielle, bisher weitgehend ungenutzte Ressource für Bioenergie. Kommunen pflegen die Grünflächen, lassen das Material aber verrotten oder führen es Deponien oder Müllverbrennungsanlagen zu. Diese Praxis ist kostenintensiv ohne für die Verwaltungen finanziellen Ausgleich bereitzustellen. Stattdessen könnte das Material energetisch verwertet werden. Zwei mögliche Techniken, um Bioenergie zu gewinnen, wurden mit krautigem Material des städtischen Straßenbegleitgrüns ...
Dissertation
Nitrogen and carbon dynamics in grassland soils and plants after application of digestate
(2015-05-20)
A better understanding of effects after digestate application on plant community, soil microbial community as well as nutrient and carbon dynamics is crucial for a sustainable grassland management and the prevention of species and functional diversity loss. The specific research objectives of the thesis were:
(i) to investigate effects after digestate application on grass species and soil microbial community, especially focussing on nitrogen dynamic in the plant-soil system and to examine the suitability of the ...