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Aufsatz
Aqueous Leaching Prior to Dewatering Improves the Quality of Solid Fuels from Grasslands
(2018-04-04)
Renewable energies are necessary to reduce greenhouse gas emissions in energy production, and biomass plays a dominant role in the renewable energy sector. Combustion of biomass constitutes an efficient conversion technique, but is hindered by harmful elements which are frequently contained in residual grassland biomass. We investigated the effect of leaching on solid fuel quality with three independent experiments including the following treatments: (1) with or without leaching, (2) with leaching at various water ...
Bachelorarbeit
Vereinbarkeit von muttergebundener Kälberaufzucht und automatischen Melksystemen
(2019-12)
Muttergebundene Kälberaufzucht stößt sowohl in der Öffentlichkeit als auch bei milchviehhaltenden (Öko-)Betrieben auf zunehmenden Zuspruch. Gleichzeitig steigt die Zahl der installierten AMS auf den Milchviehbetrieben. Diese Entwicklungen weisen darauf hin, dass in Zukunft mehr Betriebe die muttergebundene Kälberaufzucht mit den AMS kombinieren werden. Bei der Kombination besteht die Herausforderung darin, den Kühen das individuelle Melken im AMS zu gewähren und gleichzeitig die Kälber an diesen Kühen aufzuziehen. ...
Aufsatz
Urban Agriculture Oriented towards Self-Supply, Social and Commercial Purpose: A Typology
(2016-08-17)
Urban agriculture, a dynamic multifunctional phenomenon, affects the spatial diversification of urban land use, its valorization and its governance. Literature acknowledges its contribution to the development of sustainable cities. The dimension and extent of this contribution depends significantly on the particular form and function of urban agriculture. However, the complexity of interests and dimensions is insufficiently covered by theory. This paper proposes a typology for urban agriculture, supporting both theory ...
Dissertation
Entwicklung eines Modells zur Abbildung von Verfahrensketten für nachwachsende Rohstoffe
(2018-12-16)
Neben Nahrungs- und Futtermitteln werden auf landwirtschaftlichen Flächen zunehmend nach-wachsende Rohstoffen erzeugt. Dieser Trend wird durch die deutsche Bundesregierung aktiv gefördert – auch um die gesetzten Klimaziele zu erreichen. Derzeit konzentriert sich das Interesse auf Energiepflanzen und deren Verwertung. Jedoch können nachwachsende Rohstoffe auch in der Industrie eine signifikante Rolle spielen und dort unter anderem konventionelle, endliche Rohstoffe substituieren. Beispielsweise werden bereits heute ...
Aufsatz
Adoption of Organic Farming as an Opportunity for Syrian Farmers of Fresh Fruit and Vegetables: An Application of the Theory of Planned Behaviour and Structural Equation Modelling
(2017-11-04)
Exporting organic fresh fruit and vegetables (FFV) to the European Union could represent a great opportunity for Syrian farmers and exporters. Yet, the organic sector in Syria is comparatively young and only a very small area of FFV is organically managed. To date, little is known about Syrian farmers’ attitudes towards organic FFV production. Therefore, the aim of this study was to explore the intentions and attitudes of Syrian farmers of FFV towards organic farming and how likely they are to convert their farms to ...
Aufsatz
Heavy Metals and Polycyclic Aromatic Hydrocarbons in Urban Leaf Litter Designated for Combustion
(2017-03-03)
Vast amounts of leaf litter have to be disposed of by city administrations. This biomass has the potential for energy conversion, but contamination with pollutants can adversely affect this usage. We investigated leaf litter samples from the city of Kassel by analyzing their heavy metal and polycyclic aromatic hydrocarbon (PAH) concentrations. Leaf samples were indeed contaminated with heavy metals and PAHs and contamination was influenced by provenience and collection technique. A simple cleaning system of washing ...
Aufsatz
High-Quality Solid Fuel Production from Leaf Litter of Urban Street Trees
(2016-11-30)
Leaf litter is a growing concern for cities. Due to adherent dirt such biomass is rarely utilized nowadays but may constitute a renewable energy source for communities or private households. Leaf litter from main roads, residential areas and city centres collected by the vacuum technique or the sweeper technique was sampled and analysed for ash content and chemical composition. Ash content of leaf litter collected by the sweeping technique was higher (21.6%–40.1% dry matter, DM) than in material collected by the ...
Aufsatz
Effects of three leafy vegetables on the growth performance of Giant African Snail Achatina (Lissachatina) fulica
(2019-06-07)
This present research was performed to evaluate the effects of three leafy vegetable diets [bitter leaf (Vernonia amygdalina), fluted pumpkin leaf (Telfairia occidentalis) and pawpaw leaf (Carica papaya)] on the growth performance of Giant African Snail (Achatina fulica). A total of ninety (90) A. fulica were used for the study. Thirty (30) snails each were subjected to three different dietary treatments in three replicates of 10 snails per replicate and fed with the fresh leaves of these vegetables over a period of ...
Aufsatz
The impact of uncertainty on smallholder farmers' income in Kyrgyzstan
(2019-12-12)
The farming systems in the mountain areas of Kyrgyzstan are primarily characterised by small-scale crop and livestock activities. Farmers are faced with several environmental, socio-economic and political challenges and constraints that result in significant uncertainties affecting their operations. This paper attempts to model how various sources of uncertainty collectively affected the smallholders’ farm incomes during a mid-term horizon using Monte Carlo simulation. The analyses were based on data collected through ...