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Agriculture, Forestry, and Other Land Use (AFOLU) is unique among the sectors considered in this volume, since the mitigation potential is derived from both an enhancement of removals of greenhouse gases (GHG), as well as reduction of emissions through management of land and livestock (robust evidence; high agreement). The land provides food that feeds the Earth’s human population of ca. 7 billion, fibre for a variety of purposes, livelihoods for billions of people worldwide, and is a critical resource for sustainable development in many regions. Agriculture is frequently central to the livelihoods of many social groups, especially in developing countries where it often accounts for a significant share of production. In addition to food and fibre, the land provides a multitude of ecosystem services; climate change mitigation is just one of many that are vital to human well-being (robust evidence; high agreement). Mitigation options in the AFOLU sector, therefore, need to be assessed, as far as possible, for their potential impact on all other services provided by land. [Section 11.1]

Anthropogenic climate change is predicted to be a major cause of extinctions. Therefore, a major aim of climate change ecology is to understand how species are being impacted and identify which species are most at risk. However, the ability to make these broad generalisations requires large-scale comparative analyses based on appropriate assumptions. This thesis investigates how European birds respond to changes in climate, the validity of several common assumptions, and identifies which species or populations are most at risk based on multiple long-term datasets. Our understanding of how different responses relate and how they affect population persistence is lacking. A conceptual hierarchical framework is introduced in chapter one to better understand and predict when climate-induced trait changes (phenology or physiology) impact demographic rates (survival or reproduction), and subsequently population dynamics. I synthesise the literature to find hypotheses about life-history and ecological characteristics that could predict when population dynamics will likely be affected. An example shows that, although earlier laying with warmer temperatures was associated with improved reproduction, this had no apparent effect on population trends in 35 British birds. Number of broods partly explains which species are most at risk of temperature-induced population declines. It is often assumed that populations within species respond similarly to climate change, and therefore a single value will reflect species-specific responses. Chapter two explores inter- and intra-specific variation in body condition responses to six climatic variables in 46 species over 21 years and 80 sites. Body condition is sensitive to all six variables (primarily in a non-linear way), and declines with warmer temperatures. I find that species signals might not exist as populations of the same species are no more alike than populations of different species. Decreased body condition is typically assumed to have detrimental consequences on species’ vital rates and population dynamics, but this assumption has rarely been tested. Expanding on chapter two, chapter three shows that temperature-induced declines in body condition have no apparent consequences on demography and population dynamics. Instead, temperature has strong effects on reproductive success and population growth rates via unknown traits and demographic rates. Much of the literature investigating climatic impacts assumes that temporal trends accurately reflect responses to climate change, and therefore investigate trait changes over time. In chapter four, I use two long-term datasets to demonstrate that, for four different types of trait responses, trait variation through time cannot be assumed to be due to warming. Non-temperature causal agents are important…

To date, the majority of world's primary energy is derived from fossil fuels. However, the fossil fuel recourses are in an inevitable decline as energy demand continues to grow exponentially with population growth, urbanization, and improved standards of living. Crude oil prices have recently risen several times and their current annual volatility exceeds 30%. The potential scarcity of fossil fuels has prompted a global search for alternative energy resources. Biodiesel fulfills the major requirements for production of alternative fuels such as feedstock availability, technical feasibility, and economic competitiveness. Together with other renewable biofuels, the use of biodiesel as a substitute of fossil-based fuels is expected to reduce the dependence on imported petroleum and associated political and economic vulnerability, decrease greenhouse gas emissions, and revitalize the economy. The objective of this article was to provide an update of the most recent technological advancements toward clean and sustainable biodiesel production through a thorough overview of biodiesel feedstocks, most promising transesterification processes, and opportunities for glycerol utilization for value-added products. A critical analysis of the techno-economical barriers and environmental challenges that need to be addressed in future R&D efforts toward commercialization and establishment of a sustainable and cost-efficient biodiesel production is provided. Keywords: biodiesel; waste oil; microbial oil; transesterification; microwave irradiation; lipase; glycerol; triacetin; greenhouse gas emissions; trends in biodiesel R&D