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The global restoration agenda can help solve the biodiversity extinction crisis by regenerating biodiversity-rich ecosystems, maximising conservation benefits using natural regeneration. Yet, conservation is rarely the core objective of restoration, and biodiversity is often neglected in restoration projects targeted towards carbon sequestration or enhancing ecosystem services for improved local livelihoods. Here, we synthesise evidence to show that promoting biodiversity in restoration planning and delivery is integral to delivering other long-term restoration aims, such as carbon sequestration, timber production, enhanced local farm yields, reduced soil erosion, recovered hydrological services and improved human health. For each of these restoration goals, biodiversity must be a keystone objective to the entire process. Biodiversity integration requires improved evidence and action, delivered via a socio-ecological process operating at landscape scales and backed by supportive regulations and finance. Conceiving restoration and biodiversity conservation as synergistic, mutually reinforcing partners is critical for humanity's bids to tackle the global crises of climate change, land degradation and biodiversity extinction.

Synopsis Climate change can directly and indirectly affect species distribution. Warming may allow for invasive species, such as apple snails, to migrate to higher latitudes where temperatures are more conducive to their survival and invasion success. Higher temperatures and lower pH ranges have been previously documented to affect the form and function of calcium carbonate shells, which serve many functions, including protection from predators and thermoregulation. This study aimed to quantify differences in the morphology and mechanical properties of invasive apple snail, Pomacea maculata, shells after altering temperature and pH. We mechanically tested shells among three five-week treatments: control, higher temperature, and lower pH. Ultimate Strength increased in shells that were exposed to higher temperatures, but Young’s Modulus and Peak Load did not differ among control, temperature, and pH treatments. Apple snails in higher temperature tanks increased their shell length over the five-week trials. Although snail morphometrics did not differ between sexes, male shells exhibited a higher Peak Load, Young’s Modulus, and Ultimate Strength compared to female shells. Our findings are consistent with previous gastropod studies, in that a lower pH is associated with a decrease in shell size, and higher temperatures yield larger snail shells with a higher ultimate strength. Peak Load did not significantly differ among treatments, which suggests that the cross-sectional area is relatively important when considering this species mechanical performance today and in future climates. Due to the intense nutritional and calcium demands of egg production, female snails may be more susceptible to weakened shells due to low pH environments caused by climate change.

Synopsis Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO2) uptake and water vapor loss, important for predicting and managing the future of Earth’s ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.e., representing the ecosystem as an aggregate of its individuals or as a metaphorical or literal super-organ or organism. We review recent approaches to scaling-up plant water relations (hydraulics) concepts developed for organs and organisms to enable and interpret measurements at ecosystem-level. We focus on three community-scale versions of water relations traits that have potential to provide mechanistic insight into climate change responses of forest CO2 and H2O gas exchange and productivity: leaf water potential (Ψcanopy), pressure volume curves (eco-PV), and hydraulic conductance (Keco). These analyses can reveal additional ecosystem-scale parameters analogous to those typically quantified for leaves or plants (e.g., wilting point and hydraulic vulnerability) that may act as thresholds in forest responses to drought, including growth cessation, mortality, and flammability. We unite these concepts in a novel framework to predict Ψcanopy and its approaching of critical thresholds during drought, using measurements of Keco and eco-PV curves. We thus delineate how the extension of water relations concepts from organ- and organism-scales can reveal the hydraulic constraints on the interaction of vegetation and climate and provide new mechanistic understanding and prediction of forest water use and productivity.

From the British debate on the depletion of coal in 1865 to the First World Power Conference held in London in 1924, scientists, engineers, industrialists, and politicians produced new interpretations of the past, present, and future in terms of the mobilisation of energy resources. This thesis identifies an emerging ‘energy developmentalism’, which called for maximising energy use to maintain or improve a nation’s place in international competition. Energy developmentalism was not a marginal worldview confined to ‘energeticists’, but a coherent set of claims, measurements, and arguments that informed energy governance on an international scale. Rather than focusing on a single resource, energy developmentalism applied a unified schema to all energy sources, including those like solar and tidal energy that were still mostly theoretical. Drawing on sources from across Europe, while staying grounded in political changes in Britain and France, makes it possible to understand how a general formula for transforming raw materials with maximum efficiency was applied differently depending on specific political contexts. This period saw the articulation of problems like the depletion of resources, the difference between renewable and nonrenewable energy, the intermittency of renewables, the overreliance on a single source of energy, and the centrality of energy to modern economies – problems that are often associated with later periods. Scientific measurements of efficiency, horsepower, and kilowatts became operators in political debates centred on questions of national standing and progress. Even as oil became increasingly important in the world economy, the delegates at the First World Power Conference transformed a vision of a renewable energy future into one of a general expansion of energy consumption as the basis of progress. In so doing, they downplayed the continued importance of fossil fuels and equated ‘conservation’ with the fullest possible use of all energy sources, renewable or not.

Synopsis Since the late 1800s, anthropogenic activities such as fossil fuel consumption and deforestation have driven up the concentration of atmospheric CO2 around the globe by >45%. Such heightened concentrations of carbon dioxide in the atmosphere are a leading contributor to global climate change, with estimates of a 2–5° increase in global air temperature by the end of the century. While such climatic changes are mostly considered detrimental, a great deal of experimental work has shown that increased atmospheric CO2 will actually increase growth in various plants, which may lead to increased biomass for potential harvesting or CO2 sequestration. However, it is not clear whether this increase in growth or biomass will be beneficial to the plants, as such increases may lead to weaker plant materials. In this review, I examine our current understanding of how elevated atmospheric CO2 caused by anthropogenic effects may influence plant material properties, focusing on potential effects on wood. For the first part of the review, I explore how aspects of wood anatomy and structure influence resistance to bending and breakage. This information is then used to review how changes in CO2 levels may later these aspects of wood anatomy and structure in ways that have mechanical consequences. The major pattern that emerges is that the consequences of elevated CO2 on wood properties are highly dependent on species and environment, with different tree species showing contradictory responses to atmospheric changes. In the end, I describe a couple avenues for future research into better understanding the influence of atmospheric CO2 levels on plant biomaterial mechanics.

Climate change has been widely recognised as one of the most urgent and growing threats to natural and cultural heritage in the twenty-first century, and the indelible impact of humanity has led to the definition of a new geological epoch, the Anthropocene. Indigenous peoples are disproportionately affected by natural and human-induced changes to the environment. Their vulnerability is exacerbated by centuries of cultural and territorial disenfranchisement within settler-colonial nations. This dissertation aims at understanding Indigenous perceptions of heritage in the face of climate change and its intersection with the impacts of settler- colonialism. It analyses how these on-the-ground perceptions can, in turn, inform heritage organisations and contribute to safeguarding the many facets of tangible and intangible Indigenous heritage for future generations in the Anthropocene. This is accomplished through a comparative, transnational case study of two communities each from the Dehcho First Nations in the Northwest Territories, Canada, and the Aymara and Quechua peoples in northern Chile. I use a multi-method approach consisting of semi-structured interviews, oral histories and participant observation. The data is complemented by environmental and heritage legislation and grey literature at multiple organisational scales for both case studies. Three lines of enquiry are explored through an applied comparative thematic analysis: i) the perceptions of climate change and associated land loss/change among Indigenous groups and how this impacts each group’s notions of challenges to its cultural identity; ii) the intersection of the effects of post- colonialism, ongoing industrial activities and climate change on the intergenerational transmission of ancestral knowledge and notions of place attachment; and iii) how international, national and regional political and sociocultural rhetoric on environmental and heritage conservation affect local, grassroots considerations for safeguarding heritage. The similarities and contrasts of the Dehcho First Nations, Aymara and Quechua experiences of climate change across the North-South divide are related from the grassroots to arrive at redefining heritage practices in the Anthropocene. The results demonstrate that decolonising heritage is not only necessary, but that this decolonisation depends on building and actively engaging in intercultural empathy through the global threat of climate change. In order to understand how Indigenous practices, places, and items are valorised—attributed value—as heritage in the face of climate change, one must empathise with the cultural loss that exists in the temporal and cognitive spaces between Indigenous individuals’ moments of nostalgic reference and today.

Synopsis Foundational habitats such as seagrasses and coral reefs are at severe risk globally from climate warming. Infectious disease associated with warming events is both a cause of decline and an indicator of stress in both habitats. Since new approaches are needed to detect refugia and design climate-smart networks of marine protected areas, we test the hypothesis that the health of eelgrass (Zostera marina) in temperate ecosystems can serve as a proxy indicative of higher resilience and help pinpoint refugia. Eelgrass meadows worldwide are at risk from environmental stressors, including climate warming and disease. Disease outbreaks of Labyrinthula zosterae are associated with recent, widespread declines in eelgrass meadows throughout the San Juan Islands, Washington, USA. Machine language learning, drone surveys, and molecular diagnostics reveal climate impacts on seagrass wasting disease prevalence (proportion of infected individuals) and severity (proportion of infected leaf area) from San Diego, California, to Alaska. Given that warmer temperatures favor many pathogens such as L. zosterae, we hypothesize that absent or low disease severity in meadows could indicate eelgrass resilience to climate and pathogenic stressors. Regional surveys showed the San Juan Islands as a hotspot for both high disease prevalence and severity, and surveys throughout the Northeast Pacific indicated higher prevalence and severity in intertidal, rather than subtidal, meadows. Further, among sites with eelgrass declines, losses were more pronounced at sites with shallower eelgrass meadows. We suggest that deeper meadows with the lowest disease severity will be refuges from future warming and pathogenic stressors in the Northeast Pacific. Disease monitoring may be a useful conservation approach for marine foundation species, as low or absent disease severity can pinpoint resilient refugia that should be prioritized for future conservation efforts. Even in declining or at-risk habitats, disease surveys can help identify meadows that may contain especially resilient individuals for future restoration efforts. Our approach of using disease as a pulse point for eelgrass resilience to multiple stressors could be applied to other habitats such as coral reefs to inform conservation and management decisions.

Synopsis Climate change will increase the frequency and intensity of extreme climatic events (e.g., storms) that result in repeated pulses of hyposalinity in nearshore ecosystems. Sea urchins inhabit these ecosystems and are stenohaline (restricted to salinity levels ∼32‰), thus are particularly susceptible to hyposalinity events. As key benthic omnivores, sea urchins use hydrostatic adhesive tube feet for numerous functions, including attachment to and locomotion on the substratum as they graze for food. Hyposalinity severely impacts sea urchin locomotor and adhesive performance but several ecologically relevant and climate change-related questions remain. First, do sea urchin locomotion and adhesion acclimate to repeated pulses of hyposalinity? Second, how do tube feet respond to tensile forces during single and repeated hyposalinity events? Third, do the negative effects of hyposalinity exposure persist following a return to normal salinity levels? To answer these questions, we repeatedly exposed green sea urchins (Strongylocentrotus droebachiensis) to pulses of three different salinities (control: 32‰, moderate hyposalinity: 22‰, severe hyposalinity: 16‰) over the course of two months and measured locomotor performance, adhesive performance, and tube foot tensile behavior. We also measured these parameters 20 h after sea urchins returned to normal salinity levels. We found no evidence that tube feet performance and properties acclimate to repeated pulses of hyposalinity, at least over the timescale examined in this study. In contrast, hyposalinity has severe consequences on locomotion, adhesion, and tube foot tensile behavior, and these impacts are not limited to the hyposalinity exposure. Our results suggest both moderate and severe hyposalinity events have the potential to increase sea urchin dislodgment and reduce movement, which may impact sea urchin distribution and their role in marine communities.

Synopsis Climatic and geomorphological changes during the Quaternary period impacted global patterns of speciation and diversification across a wide range of taxa, but few studies have examined these effects on African riverine fish. The lower Congo River is an excellent natural laboratory for understanding complex speciation and population diversification processes, as it is hydrologically extremely dynamic and recognized as a continental hotspot of diversity harboring many narrowly endemic species. A previous study using genome-wide SNP data highlighted the importance of dynamic hydrological regimes to the diversification and speciation in lower Congo River cichlids. However, historical climate and hydrological changes (e.g., reduced river discharge during extended dry periods) have likely also influenced ichthyofaunal diversification processes in this system. The lower Congo River offers a unique opportunity to study climate-driven changes in river discharge, given the massive volume of water from the entire Congo basin flowing through this short stretch of the river. Here, we, for the first time, investigate the impacts of paleoclimatic factors on ichthyofaunal diversification in this system by inferring divergence times and modeling patterns of gene flow in four endemic lamprologine cichlids, including the blind cichlid, Lamprologus lethops. Our results suggest that Quaternary climate changes associated with river discharge fluctuations may have impacted the diversification of species along the system and the emergence of cryptophthalmic phenotype in some endemic species. Our study, using reduced representation sequencing (2RADseq), indicates that the lower Congo River lamprologines emerged during the Early-Middle Pleistocene transition, characterized as one of the earth’s major climatic transformation periods. Modeling results suggest that gene flow across populations and between species was not constant but occurred in temporally constrained pulses. We show that these results correlate with glacial–interglacial fluctuations. The current hyper-diverse fish assemblages of the lower Congo River riverscape likely reflect the synergistic effects of multiple drivers fueling complex evolutionary processes through time.