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Dissertation
The status and barriers to the implementation and continuation of the school gardening projects in Germany, Nigeria and the United States of America
(2010-10-25)
In drawing a conclusion for this study, care must be taken in generalizing findings since the population of students and teachers investigated were limited to certain levels in the different schools and countries. This study recognized some complexity of the factors underlying the status of school gardening instruction and activities in Germany, Nigeria and the U.S. as inadequate time for decision-making in the process of gardening, motivation of teachers and students. This was seen as the major impediments that ...
Dissertation
Analyzing Gene Centres with the Help of the Checklist Method – the Case of Syria
(2016-06-07)
The present survey of species diversity of cultivated plants is the first for Syria. Some cultivated species will be added in the future, because due to the civil war in Syria, it was not possible to visit the country in the frame of the present work, as initially planned. Checklists proved to be a useful tool for overviewing the cultivated plants of selected areas and allow a characterization of the state of plant genetic resources of Syria.
Syria has experienced several civilizations. Man settled in this productive ...
Dissertation
Nitrogen and Energy Utilization on Conventional and Organic Dairy Farms in Norway
(2017-04-10)
Zusammenfassung:
In allen Wirtschaftszweigen muss die Ausnutzung der verwendeten Energie und Nährstoffe verbessert werden, um die umweltbezogene Nachhaltigkeit zu verbessern. Ziel dieser Arbeit war es, den Ausnutzungsgrad von Energie und Stickstoff auf norwegischen Milchviehbetrieben zu analysieren und zu untersuchen, ob der Ausnutzungsgrad erhöht werden kann.
Die Daten für die Studie wurden von 2010 bis 2012 auf 10 konventionell und 10 ökologisch bewirtschafteten Betrieben erhoben. Für Stickstoff wurde eine ...
Dissertation
Biomass, quality traits and methane production of extensive grassland: biodiversity effects and sensor approaches
(2016-06-07)
Energy policies around the world are mandating for a progressive increase in renewable energy production. Extensive grassland areas with low productivity and land use limitations have become target areas for sustainable energy production to avoid competition with food production on the limited available arable land resources and minimize further conversion of grassland into intensively managed energy cropping systems or abandonment. However, the high spatio-temporal variability in botanical composition and biochemical ...
Dissertation
Combined use of spectral signatures and ultrasonic sward height for the assessment of biomass and quality parameters in heterogeneous pastures
(2017-06-21)
Precision management of grasslands requires accurate information on sward characteristics at a spatial and temporal scale. Multi-sensor data fusion provides data for site-specific grassland management. The present study aimed to demonstrate the potential of using a combination of ultrasonic and hyper-spectral sensor data fusion to predict forage quality (crude protein and acid detergent fiber) and biomass in heterogeneous pastures. The ability of a mobile sensing system equipped with both sensors to quantify within-field ...
Dissertation
Energetische Verwertung städtischen Laubs
(2017-11-28)
Das relativ saubere Parklaub und verschmutzte städtische Straßenlaub wurde durch das IFBB-Verfahren nach seiner energetischen Verwertbarkeit untersucht. Das Parklaub wurde durch das typische IFBB-Verfahren verarbeitet. Da das Straßenlaub durch Störstoffe (Sand, Kies, Plastik, Papier, Metallstücke) belastet war, bestand die Notwendigkeit es gründlich zu reinigen. Deswegen wurde der Vorgang der Konditionierung des IFBB-Verfahrens bei 40°C bei Straßenlaub durch den Reinigungsprozess bei 10-12°C ersetzt. Das Pressen in ...
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 ...