Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 41-47).

Climate change has become the most important global environmental problem we face today. Agriculture, forestry and the land use sector not only contribute to national economies but also provide a source of greenhouse gas (GHG) emissions as well as a carbon store, contributing approximately 20% but removing about 16%. Energy crops and associated increases in soil carbon sequestration from different ground covers through various land management strategies are examples of approaches that could be adopted to reduce GHG emissions. A number of these options have an associated economic cost to the land manager and it is important to understand what is economically and socially viable by understanding the link between energy crop adoption and a range of socio-economic factors. Agent-based modelling (ABMs) has been identified as providing a promising approach to integrate social, economic and biophysical processes. In the past these areas of research have been mainly studied separately but now there is an urgent need to address these areas in a combined way. Economic rationalisation is fundamental to farmers’ decision-making, although not wholly representative and non-economic factors were identified. The estimated GHG mitigation potential of bioenergy crops at current adoption levels is modest when taking Scotland’s national GHG emissions into account, however, more significant when considering the agricultural sector in isolation. This contribution can only increase with improved management practices and policy designed to encourage adoption and improve energy security. This work will contribute to a greater understanding of bioenergy land use strategies. This project used North East Scotland as the case study, with raw data collated by questionnaire, however, conclusions drawn add to the broader understanding of the link between socio-economic activity, bioenergy adoption and GHG emissions.

Thesis (Ph.D.)--University of Wisconsin--Madison, 2009. / Advisor: Kevin Shinners. Includes bibliographical references. Also available on the Internet.

The second generation bioenergy crops Miscanthus x giganteus and short rotation coppice (SRC) willow are the two main bioenergy crops in the UK and have become an integral part of legislation to provide an alternative to fossil fuels and to reduce national greenhouse gas (GHG) emissions. To reach emission targets, it is estimated that approximately 350,000 ha of land could be made available for bioenergy crops by 2020. Despite the promise of these crops, there have been very few field-studies regarding soil GHG (CO2, CH4 and N2O) emissions and many of the published studies are life cycle analyses or modelled fluxes from soils using default values from the IPCC. The first aim of this research was to quantify the in situ soil GHG budget and to establish the drivers of these GHG fluxes for Miscanthus and SRC willow. The second aim of this research was to provide a more in-depth understanding of C cycling under Miscanthus i.e. litter and roots through two field experiments. Overall, the results from this work confirm minimal emissions of CH4 and N2O from soil under Miscanthus and SRC willow. CO2 flux was found to be the major efflux from soils and it was found in Miscanthus, that the majority of this flux was derived from below ground respiration. Litter played an important part in providing nutrients to the soil, which is vital in systems that are not fertilised. Litter also contributed to SOM accumulation on the soil surface and may promote long-term C sequestration. The results from this work combined with other literature would suggest that these second generation crops offer advantages to first generation crops, but more field-based studies are required to say if they can offer the large-scale GHG savings needed to be a viable alternative to fossil fuels.

Development of biomass energy plantations is one approach to mitigate and adapt to climate change and the energy challenges related to it; however, climate change will affect the climate conditions and in turn the selection of crops and trees suitable for renewable energy sources. In Estonia, electricity is mainly based on oil shale but since their integration in the European Union they are required to increase the share of energy from renewable sources. In this study, the possible changes of suitable species are assessed by examining the current and the future prospects and potentials with biomass energy derived from energy plantations in Estonia, taking climate change into consideration. The biomass energy potentials for the species that are climate suitable in current and future time are manually estimated, using a case study approach when determining the yields. The study result suggests that biomass energy from crops and trees have great development possibilities and that climate is not a key limitation for the selection of suitable species; in addition, the energy crops and trees appear to suit the future climate conditions better than the current. The results indicate that the established national target of 25% of energy from renewable sources in gross final consumption of energy by 2020 could be achieved to a large extent by putting energy plantations into practice.

Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2009. / Submitted to the African Centre for Crop Improvement. Full text also available online. Scroll down for electronic link.

Thesis (Ph. D. - Arid Lands Resource Sciences)--University of Arizona, 1983. / Includes bibliographical references (leaves 164-170).