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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…

Scientific evidence and evidence-based reasoning are likely to face epistemological challenges when brought into societal debate if their foundational assumptions generate cognitive dissonance among key elements of the community. The risk of dissonance is even greater when scientific demonstrations and models are concerned with the decisions and behaviours of people interacting with an environment of interest. In this case, scientific information is often perceived as distorted or biased due to the inherent uncertainties attached to human ecosystems Human ecosystems are complex and adaptive, largely due to our individual cognitive capacities and communication skills. Complex systems science aims to track uncertainties attached to these systems by exploring metaphoric models of reality.

Creative arts have long been used for making meaning and conveying knowledge. Music, dance, painting, and storytelling are art forms that have the power to connect us to each other. This research investigates using the arts to connect us to the planet as well. I refer to this relationship as Econnection. Originally published as “Creative Arts-based Pedagogies in Early Childhood Education for Sustainability (EfS): Challenges and Possibilities” (Ward, 2013) the central research question was: In what ways can self-generated creative arts experiences assist early childhood educators to support young children to learn about the environment?

Industrial poplar plantations represent a strategic source of wood products for many countries. Harvested after 10 to 30 years, they yield about 200 t ha-1 of timber and 100 t ha-1 industrial wood. The latter is obtained from poplar tops, which can be converted into chips, or a mix of pulpwood and chips. The study compared four options to process poplar tops. Alternatives derived from the intersection of two product strategies (pulpwood and chips, or chips only) with two pulpwood processing methods (manual or mechanized). Both mechanization and simplification (only one product) succeeded in reducing production cost, but the former had a stronger effect. The tests demonstrated that all options were cost-effective and could return some profits. However, the exclusive production of chips offered lower profits, compared to an articulate product strategy aimed at maximising value recovery. In the case of Italian poplar plantations, the price difference between pulp and chips is generally larger than the cost reduction obtained with integral chipping. Similar conclusions were reached by other authors working with spruce and beech in Central Europe. Of course, this is only true for the current price levels of pulpwood and chips: results may change, if this price balance will be altered by the growing demand for biomass fuel.

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]

In this current period of the Anthropocene, where human impact on planetary systems is greater than ever before (Crutzen & Ramanathan, 2000; Guggenheim, 2006), the practice of, and research about, sustainability education for young children is becoming more nuanced and multidisciplinary. The research discussed in this chapter is based on the premise that engaging in ecological place-based stories and arts experiences for investigating the natural world help us to understand the basis of our relationship with these ecosystems in our local, regional and global environments (Ward, 2013). Indeed, the arts are an important, multifaceted lens through which to investigate, interpret and understand the natural world (for example, see contributions by Shirvington and Gray & Thomson, this volume). Our exploration of natural and manufactured materials, our understanding of their visceral realness and provenance, is discovered, conceptualised, felt, imagined and rendered tangible by the arts.

The aim of this study was to evaluate the utility of the [(14)C]-sodium bicarbonate/urea technique to detect physical activity-induced increases in total energy expenditure in free-living healthy men. Thirteen healthy males aged 34.1 +/- 11.7 yrs with body mass index 24.1 +/- 3.1 kg/m(2) were studied on three separate occasions, during which [(14)C]-bicarbonate was infused over 48-hours and urine was collected during the second 24-hours. On three separate occasions and in random order, subjects either remained sedentary, or performed a bout of physical activity on an electro-magnetically braked cycle ergometer sufficient to increase energy expenditure by 7% or 11% above predicted sedentary total energy expenditure. Urine samples were analyzed to evaluate the amount of [(14)C]-bicarbonate incorporated into urinary urea, thereby reflecting the amount of CO(2) produced per day, and upon conversion, the number of kilojoules of energy expended in 24-hours. All 13 subjects successfully completed the two physical activity treatments and there were no adverse events. As measured by the [(14)C]-urea assay, mean total energy expenditure values were not significantly different between sedentary activity (17902 +/- 905 kJ/day), the physical activity treatment designed to increase TEE by 7% (17701 +/- 594 kJ/day) and the physical activity treatment designed to increase TEE by 11% (18538 +/- 485 kJ/day) (P=0.668). In conclusion, although the [(14)C]-sodium bicarbonate/urea technique was well tolerated and did not interfere with normal daily activities, it was not able to accurately measure physical activity-induced increases in EE in the range of 7-11% above predicted sedentary total energy expenditure.

Der Klimawandel wird sich voraussichtlich auf das Grundwasser auswirken, aber die Prognosen sind sehr unsicher. Die Quantifizierung der historischen Auswirkungen ermöglicht ein besseres Verständnis der Reaktion des Grundwassers, wurde aber aufgrund des komplexen Einflusses verschiedener Faktoren, wie Grundwasserentnahme für die landwirtschaftliche Bewässerung und Landnutzungsänderungen, nur selten untersucht. Diese Arbeit zielt darauf ab, zum Verständnis und zur Quantifizierung der historischen Auswirkungen von Klimawandel und -schwankungen auf das Grundwasser durch drei miteinander verbundene Forschungsfragen beizutragen: Frage 1: Wie sensitiv reagieren der Grundwasserstand und die Grundwasserneubildung auf Klimaschwankungen in Australien? Frage 2: Wie stark sind die Veränderungen des Grundwasserstands auf den anthropogenen Klimawandel in Australien zurückzuführen und wann haben sich diese Auswirkungen auf das Grundwasser bemerkbar gemacht? Frage 3: Wie haben und werden sich die langfristigen Klimawandel und -schwankungen auf den Grundwasserabfluss (niedriger, mittlerer und hoher Abfluss) in einem großen Karsteinzugsgebiet (schneebeeinflusst, gemäßigtes Klima) in Mitteleuropa auswirken? Die Frage 1 wurde durch Quantifizierung der Sensitivität des Grundwasserstands und der Grundwasserneubildung gegenüber Klimaschwankungen in Australien untersucht. Insgesamt 4350 Messstellen wurden zunächst mit der Zeitreihen-Grundwasser-Toolbox HydroSight modelliert, und 1143 (26%) davon wurden als klimadominierte Messstellen identifiziert. Zur Quantifizierung der Grundwassersensitivität wurde dann ein multipler linearer Regressionsansatz angewandt, der an Studien zur Elastizität von Wasserflüssen adaptiert wurde. Die Ergebnisse zeigen, dass der Grundwasserstand und die Grundwasserneubildung etwa achtmal sensitiver auf Niederschläge reagieren als auf Veränderungen der potenziellen Evapotranspiration. Die inhärenten Eigenschaften der Gebiete, wie Klimatyp und Hydrogeologie, scheinen eine wichtige Rolle bei der Kontrolle der Grundwassersensitivität zu spielen. Die Frage 2 wurde untersucht, indem historische Veränderungen des Grundwasserstands in Australien festgestellt und auf den anthropogenen Klimawandel zurückgeführt wurden. An den vom Klima dominierten Standorten wurde ein Modellierungsexperiment durchgeführt, um die Veränderungen des Grundwasserstands sowohl in der faktischen als auch in der kontrafaktischen (natürlichen) Welt mit und ohne menschlichen Einfluss zu simulieren. Die Ergebnisse zeigen, dass 90% der Standorte seit den 1950er Jahren eine signifikante Grundwasserabsenkung erfahren haben, die auf den anthropogenen Klimawandel zurückzuführen ist. Im Südwesten Australien ist die Abnahme am höchsten und liegt viermal so hoch wie der nationale Median (-74 gegenüber -19 mm pro Jahr). Diese Ergebnisse gehören zu den ersten, die zeigen, dass das Grundwasser bereits seit längerer Zeit den negativen Auswirkungen des anthropogenen Klimawandels leidet. Zur Beantwortung von Frage 3 wurde die Reaktion des Grundwasserabflusses auf Klimawandel und -schwankungen in einem schneebeeinflussten Karsteinzugsgebiet der gemäßigten Breiten (Blautopf) in Süddeutschland zwischen 1952 und 2100 quantifiziert. In dieser Studie wurden statistische Methoden und konzeptionelle Modellierungen eingesetzt, um die langfristigen Auswirkungen zu quantifizieren. Die Ergebnisse zeigen, dass die Veränderungen des jährlichen mittleren und niedrigen Abflusses nicht signifikant waren, aber der jährliche Spitzenabfluss hat sich aufgrund der weniger intensiven Schneeschmelze auf einen niedrigen Wert (< 13,6 m3/s) verschoben. Trotz nicht signifikanter historischer Veränderungen werden alle hoch-, niedrig- und mittleren Abflüsse bis zum Jahr 2100 voraussichtlich abnehmen. Diese Ergebnisse können auf potenzielle Risiken der Wassermangelversorgung an ähnlichen klimatischen und geologischen Standorten hinweisen. Die Quantifizierung der historischen Auswirkungen von Klimawandel und -schwankungen auf das Grundwasser trägt zu einem besseren Verständnis der Reaktion des Grundwassers bei und erhöht die Zuverlässigkeit der Vorhersagen. Nur wenn wir die Vergangenheit verstehen, können wir bessere Vorhersagen für die Zukunft machen.

Most photovoltaic (PV) string inverters have the hardware capability to measure at least part of the current-voltage (I-V) characteristic curve of the PV strings connected at the input. However, this intrinsic capability of the inverters is not used, since I-V curve measurement and monitoring functions are not implemented in the inverter control software. In this paper, we aim to show how such a functionality can be useful for PV system monitoring purposes, to detect the presence and cause of power-loss in the PV strings, be it due to shading, degradation of the PV modules or balance-of-system components through increased series resistance losses, or shunting of the PV modules. To achieve this, we propose and experimentally demonstrate three complementary PV system monitoring methods that make use of the I-V curve measurement capability of a commercial string inverter. The first method is suitable for monitoring single or independent PV strings, and is based on evaluating the ratio of certain operation points on the string I-V curve. The second method is applicable to PV systems with identical strings, and is based on monitoring and inter-comparison of string I-V curve parameters. For PV systems with non-identical strings, or when all strings can be affected by faults, we propose to use in-plane irradiance and module temperature measurements, and a performance model of the PV strings, to predict the optimal string I-V curve parameters, and then perform the inter-comparison with the measured values, to identify the cause of the faults. 31st European Photovoltaic Solar Energy Conference and Exhibition; 1667-1674