In this PhD study, I aim to deepen our understanding of the influence of major mycorrhizal types, namely arbuscular mycorrhizae (AM) and ectomycorrhizae (EM), on the global soil carbon cycle and... Show moreIn this PhD study, I aim to deepen our understanding of the influence of major mycorrhizal types, namely arbuscular mycorrhizae (AM) and ectomycorrhizae (EM), on the global soil carbon cycle and their potential distribution changes under future environmental shifts. The investigation comprises two main perspectives: Firstly, Chapter 2 delves into their direct impact on fungal biomass input to the soil via lab experiments. Secondly, Chapters 3, 4, and 5 explore their role in mediating litter decomposition through modeling. This thesis sheds light on the significance of mycorrhizal fungi in the soil carbon cycle and underscores the necessity of accounting for their effects when analyzing global soil carbon dynamics. Additionally, the research underscores the importance of understanding mycorrhizal fungi responses to environmental changes, given their sensitivity to factors like temperature and precipitation. Show less
Current climate and environmental changes have brought unprecedented rates of change to mountain ecosystems. These changes are impacting the provisioning of ecosystem services. Despite the... Show moreCurrent climate and environmental changes have brought unprecedented rates of change to mountain ecosystems. These changes are impacting the provisioning of ecosystem services. Despite the increase in academic publications on ecosystem services, research on cultural ecosystem services (CES) and their availability in mountain regions has largely been neglected. Here we analyse how important different CES are for inhabitants and visitors in the Lower Engadine region (Switzerland). We use questionnaires and maps to identify the most important CES for individual and collective wellbeing as well as their geographical location in the region. We had 48 participants in this study of which 28 grew up in the Lower Engadine. Our results show that the most important (i.e., ‘Highly important’) CES are: ‘The view of mountains, rivers or glaciers’; the presence of plants typical for the region, for example Fire Lily and Edelweiss (i.e., Lilium bulbiliferum subsp. croceum, Edelweiss-Leontopodium alpinum); ‘Hiking’; ‘Local customs’; ‘Watching large mammals’; and the importance of ‘Terraces for traditional Agriculture activities’. Results from the spatial analysis show that identical geographical locations in the Lower Engadine provide multiple CES and bring health benefits to the users. Show less
This research delves into the decision-making processes within Brazilian energy governance, with a particular focus on its engagement with international climate change mitigation agreements. The... Show moreThis research delves into the decision-making processes within Brazilian energy governance, with a particular focus on its engagement with international climate change mitigation agreements. The recurrent utilization of power relations strategies in the nation's energy governance hinders the development of policies that facilitate an transition towards sustainable energy sources. The presence of monopolistic and oligopolistic practices, fuelled by crony capitalism and rent-seeking, not only shapes policy decisions but also enforces the adoption of established technologies. Furthermore, the exploration of behavioural dynamics in policymaking, as investigated through behavioural economics, sheds light on the fact that policymakers are influenced not solely by political, economic, and institutional challenges, but also by deeply ingrained personal behaviours. These behaviours wield significant influence over the decision-making processes and contribute to the prevailing inertia in the Brazilian energy sector. Brazil stands as the fifth-largest country in the world, the sixth most populous, the thirteenth highest emitter of greenhouse gases, and boasts 60 percent of the Amazon, the planet's largest forest, within its borders. These attributes position Brazil at the forefront of global climate governance efforts. An in-depth understanding and vigilant monitoring of the Brazilian context play a vital role in advancing worldwide initiatives to combat climate change. Show less
Verstraeten, W.W.; Bruffaerts, N.; Kouznetsov, R.; Weger, L. de; Sofiev, M.; Delcloo, A.W. 2023
Changes in climate and land-use may elicit an increased emission of allergenic pollen amounts in the air, causing a rise in respiratory allergies and affecting public health more than previously... Show moreChanges in climate and land-use may elicit an increased emission of allergenic pollen amounts in the air, causing a rise in respiratory allergies and affecting public health more than previously thought. Here we have used a well -established pollen transport model SILAM (System for Integrated modeLling of Atmospheric coMposition) for attributing the long-term changes in airborne pollen concentrations of birches and grasses to climate change and vegetation dynamics. The pollen transport model is applied for Belgium and is driven by ECMWF ERA5 mete-orological data (European Centre for Medium-Range Weather Forecasts, fifth generation of ECMWF atmospheric reanalysis of the global climate). The dynamic vegetation components of the model are based on multi-decadal datasets for 1982-2019 on spatially distributed birch and grass pollen emission sources. For each model gridcell we have computed the change rate of the seasonal birch and grass pollen cycles based on daily pollen concen-trations, and of the daily meteorological model input. Finally, the gridcell based association between trends in pollen and climate change are derived. Our findings show that during the period 1982-2019 a strong increase in birch pollen concentrations is associated with increasing radiation, decreasing precipitation and decreasing horizontal wind speed near the surface. A strong decrease of grass pollen concentrations over time is driven by a decreasing trend in grass pollen sources, and it is also associated with decreasing precipitation. The magnitude of the associations between meteorology and airborne birch pollen concentrations are almost twice the association between meteorology and grass pollen, and the spatial variations are substantial even on the scales of small countries. The specific contribution of birch tree and pollen production dynamics to the concentrations of birch pollen in the air over time is highly associated with wind speed and precipitation. Introducing the inter-seasonal variation in birch pollen production during the period 1982-2019 intensifies the climate induced increase of airborne birch pollen concentrations with-6%. In contrast, the grass pollen production dynamics resulted into-10 times less grass pollen over the studied period compared to climate change effects. Show less
This chapter provides an overview of the kind of questions one has to answer to take position on the question of who owes what to future generations in the context of climate change and discusses... Show moreThis chapter provides an overview of the kind of questions one has to answer to take position on the question of who owes what to future generations in the context of climate change and discusses several possible answers as well as their upsides and downsides. It first asks whether we have duties of justice to future at all, raising several challenges to the idea of including future generations under the scope of justice. Second, it asks how much we owe to future people: equality, sufficiency, or just basic human rights. Even if there are theoretical reasons to embrace a more demanding account, there may be political or feasibility reasons to endorse a less demanding view. The third question is what we owe to future people: what kind of world, with what kind of goods and opportunities, do we owe to future people? Before concluding, the chapter discusses the distribution of duties to future people among contemporaries, the idea that we might have to limit the amount of future people, and possible institutional responses to challenges of intergenerational justice. Show less
Harpprecht, C.I.; Miranda Xicotencatl, B.; Nielen, S.S. van; Meide, M.T. van der; Li, C.; Li, Z.; Steubing, B.R.P. 2023
Metals have an important role in the global economy. With the energy transition, the demand for many metals is expected to sharply increase in the future. Although many studies apply prospective... Show moreMetals have an important role in the global economy. With the energy transition, the demand for many metals is expected to sharply increase in the future. Although many studies apply prospective LCA to assess future environmental impacts of metal supply, the methods have not yet converged to a common approach. This study aims to provide an overview of these studies and their approaches, following 2 research questions: 1. Which metals have been addressed by previous prospective LCA studies and what are their expected future supply impacts according to the identified studies? 2. What are the studied parameters of the metal supply chains, the applied scenario modelling approaches, and data sources used? We performed a systematic literature review to identify studies which assess future environmental impacts due to the supply of metals. This includes publications about absolute impacts of global metal demand, but also relative impacts assessed by comparative LCAs of emerging technologies. For these studies, we analysed both the results and the methods to integrate prospective elements in the LCA models focussing on the choice of parameters, background scenarios, data sources and modelling approaches. The literature review yielded 40 papers. We found that the majority of publications investigate bulk metals like Cu, Fe and Al. Most studies investigate relative impacts (i.e. per kg metal produced). Fewer studies also address absolute impacts of the total future demand; however, these mostly agree that absolute environmental impacts associated with global metal demand are likely to increase. Moreover, the results show that the majority of studies assess CO2 emissions, while other impacts are less often investigated. Furthermore, we found that the parameters considered most frequently are future ore grades, recycling shares, and energy efficiency. Background scenarios were primarily energy scenarios, which were most often electricity scenarios from the integrated assessment model IMAGE. Background scenarios modelling other developments are less common. Overall, the review reveals a wide variety of parameter choices, scenario modelling approaches and data sources. This study stresses the necessity to reduce environmental impacts of metal supply. Moreover, it highlights the need for guidelines for prospective LCA as well as for the documentation of modelling choices, LCI and scenario data to facilitate transparency and sharing of LCA scenarios in the community. Show less
Decarbonizing the building stock is critical for realizing the climate-neutral target for the Netherlands. This thesis uses multi-source data, mainly including GIS data of building footprints and... Show moreDecarbonizing the building stock is critical for realizing the climate-neutral target for the Netherlands. This thesis uses multi-source data, mainly including GIS data of building footprints and the archetypes representative of Dutch residential buildings, to develop a series of bottom-up building stock models to track future material stock and flows, energy demand, electricity generation, and GHG emissions. Results demonstrate the great potential for decarbonizing the Dutch residential building sector, while decarbonization strategies should be effectively and extensively implemented. Saving space heating energy consumption is the most direct way to reduce annual GHG emissions. Considering that most existing residential buildings will still be in use in 2050, renovating them with high energy performance standards is required. Despite the great potential of renovation, it alone is not enough to realize the climate-neutral target in the residential building stock because the upstream fossil fuel-based energy systems still emit large amounts of GHG. Replacing fossil fuels with renewable energy sources is a critical path, mainly involving onsite natural gas combustion for space heating and offsite natural gas and coal combustion for electricity and heat (in heat networks) generation. Urban mining cannot contribute to as much GHG emission reduction as energy transition strategies, though, should still be implemented as it can reduce the primary material consumption and CDW landfill. In addition to the technical aspects considered in this thesis, it is also necessary to develop feasible policies in terms of socioeconomic aspects to guarantee the effective and quick deployment of these technical strategies. Show less
This thesis examines the impacts and challenges of water use of electric power system. This thesis found that there are large differences in water use of electricity technologies, with hydropower... Show moreThis thesis examines the impacts and challenges of water use of electric power system. This thesis found that there are large differences in water use of electricity technologies, with hydropower and thermal power being two large water users. Water is used for power production and then virtually transmitted via power transmission networks. From this angle, regional water stress can be influenced by power transmission across regions. The power system has further impacts on freshwater biodiversity because of its freshwater consumption and thermal emissions. Power system faces challenges when its water demand cannot be met. Carbon capture and storage is an important approach to reducing carbon emissions of power plants, while it requires additional water resources and could exacerbate the vulnerability of power system to water stress. It is necessary to deepen the analyses of the links between energy and water systems and incorporate the results into future energy and water management. Show less
This book honours Prof Bob Wishitemi. Commemorating his death in 2021, this book includes articles by his former colleagues and other scientists who worked with him over the years. The volume... Show moreThis book honours Prof Bob Wishitemi. Commemorating his death in 2021, this book includes articles by his former colleagues and other scientists who worked with him over the years. The volume contains 12 articles and presents a variety of approaches to address the major challenges facing sustainable tourism in sub-Saharan Africa: climate change and biodiversity loss. Show less
The global agri-food system plays a critical role in food security and environmental issues. Increasing globalization has resulted in a complex international food system where production and... Show moreThe global agri-food system plays a critical role in food security and environmental issues. Increasing globalization has resulted in a complex international food system where production and consumption along the international supply chain can incorporate many geographically distinct regions. This interconnection means that it is difficult for any single producer or consumer to address these impacts. This thesis represents a step towards mapping the global food system from producers to consumers and offers several policy-relevant insights, especially in the national accounting of environmental footprints. Given that many drivers occur locally, but are traded globally, and that inter-regional differences in consumption are increasingly important, it is a natural next step to find approaches that can connect local impacts (production side) with global consumption (consumption side) through trade.Global spatially explicit multi-regional input-output (SMRIO) analyses can help identify hotspots of local production and associated social and environmental impacts driven by global consumption. In this thesis, I assess the use of SMRIO in the past and build a SMRIO model in three different case studies to assess its use. I use SMRIO models to investigate three critical issues (i.e. food security, biodiversity loss, and climate change) in the agri-food system.These sorts of assessments can help provide insights into how we might avoid catastrophic environmental problems in a globalized world. However, any of the benefits highlighted in these studies will require significant international action and collaboration. They will have to be sensitive to local conditions and the economic ramifications of rapid food transitions. Show less
This study has examined traditional coping systems, emerging adaptation strategies and barriers to the adoption of these strategies. Structured questionnaires on coping and adaptation strategies... Show moreThis study has examined traditional coping systems, emerging adaptation strategies and barriers to the adoption of these strategies. Structured questionnaires on coping and adaptation strategies were conducted among Nyangatom households, expounded by focus group discussions and key informant interviews. Correlations between times series (1987–2016) on rainfall, temperature and the local perceptions on CC were examined. The time series analysis confirmed pastoralists' perception that the frequency of extreme drought has increased since 1987. The Nyangatom responded by temporal migration and herd diversification. Other responses include flood cultivation and enhancing alliance formation with other ethnic groups. Multi-nominal logistic regression analyses indicated that age of household head (−), livestock ownership (+), crop productivity (+), off-farm income (+) and access to climate information (+) proved to be key determinants with a statistically significant (negative or positive) effect on adoption. Other factors that hindered climate change adaption include intermittent conflicts with neighbouring ethnic groups and limited access to alternative livelihood options. Interventions to facilitate transition towards sustainable, adaptation-based communities need to incorporate deliberate, longer-term, risk-reducing strategies, including rangeland management, water harvesting and small scale-irrigation schemes. Improved education access, extension services, and a conducive pastoral policy environment will help to enhance the Nyangatom adaptive capacity. Show less
Woolly mammoth fossils on an island where the species eventually dies out, human and animal fossils on the bottom of the North Sea, remains of Siberian unicorns and exceptionally well-preserved... Show moreWoolly mammoth fossils on an island where the species eventually dies out, human and animal fossils on the bottom of the North Sea, remains of Siberian unicorns and exceptionally well-preserved bones from 300,000 years ago from the famous Schöningen archaeological site in Germany: these are the main topics discussed in this thesis.In this dissertation, a vast amount of isotope (d13C and d15N) data from bulk collagen of Quaternary mammalian fossils are presented and discussed. Most of these data are measured at the Centre for Isotope Research (CIO), Groningen (n > 400). The dataset consists of samples from various localities within Eurasia and are taken from human fossils, but mainly from fossils of various animal taxa including extinct species. Many of these faunal species belong to the typical ‘Mammoth steppe fauna’.The results shed light on dietary and habitat characteristics of these animals and hominins through time and space, often during episodes of dramatic climate change. Overall, this thesis, a study of stable isotope data from mammalian fossils, contributes to our understanding of ecological conditions during the Pleistocene / Early Holocene in Eurasia. Show less
The coexistence of different species of large herbivores (ungulates) in grasslands and savannas has fascinated ecologists for decades. However, changes in climate, land‐use and trophic structure of... Show moreThe coexistence of different species of large herbivores (ungulates) in grasslands and savannas has fascinated ecologists for decades. However, changes in climate, land‐use and trophic structure of ecosystems increasingly jeopardise the persistence of such diverse assemblages. Body size has been used successfully to explain ungulate niche differentiation with regard to food requirements and predation sensitivity. But this single trait axis insufficiently captures interspecific differences in water requirements and thermoregulatory capacity and thus sensitivity to climate change. Here, we develop a two‐dimensional trait space of body size and minimum dung moisture content that characterises the combined food and water requirements of large herbivores. From this, we predict that increased spatial homogeneity in water availability in drylands reduces the number of ungulate species that will coexist. But we also predict that extreme droughts will cause the larger, water‐dependent grazers as wildebeest, zebra and buffalo–dominant species in savanna ecosystems – to be replaced by smaller, less water‐dependent species. Subsequently, we explore how other constraints such as predation risk and thermoregulation are connected to this two‐dimensional framework. Our novel framework integrates multiple simultaneous stressors for herbivores and yields an extensive set of testable hypotheses about the expected changes in large herbivore community composition following climate change. Show less
The rate of climate warming in the Arctic nearly doubles warming in the temperate regions. In the arctic tundra, this warming has already altered vegetation, with strong declines in lichens... Show more The rate of climate warming in the Arctic nearly doubles warming in the temperate regions. In the arctic tundra, this warming has already altered vegetation, with strong declines in lichens and mosses and expansion of shrubs. This process called “the greening of the Arctic” has important consequences for the global nutrient cycling and emission of green-house gases to the atmosphere. Even though, plant community dynamics has been monitored in tundra, the effect of climate warming on belowground fungi remained largely unknown, despite the known key roles that fungi play providing the plants with water and nutrients in nutrient-poor arctic soils. This thesis addresses the effect of climate warming on arctic soil fungal communities by DNA-metabarcoding. Climate warming had a strong effect on fungal community composition leading to a strong decline in diversity of lichenized, moss-associated, and ectomycorrhizal fungi. Instead, many species of saprotrophic and parasitic fungi took over. These changes are expected to alter nutrient turnover in tundra soils (including decomposition and CO2 flux) and affect populations of plants and animals (for example, caribous that are feeding on lichenized fungi in winter). Show less
Van der Horn, Sarah A.; Van Kolfschoten, Thijs; Van der Plicht, Johannes; Hoek, Wim Z. 2015
Lake Victoria cichlids show the fastest vertebrate adaptive radiation known which is why they function as a model organism to study evolution. In the past 40 years, Lake Victoria experienced severe... Show moreLake Victoria cichlids show the fastest vertebrate adaptive radiation known which is why they function as a model organism to study evolution. In the past 40 years, Lake Victoria experienced severe environmental changes including the boom of the introduced, predatory Nile perch and eutrophication. Both environmental changes resulted in a decline of haplochromine cichlid species and numbers during the 1980s. However, during the 1990s and 2000s, some haplochromine species recovered. With the use of the unique Lake Victoria cichlid of collection of the Naturalis Biodiversity Center, this thesis showed how the haplochromines have adapted their ecomorphology to the changed environment. In response to a decrease in water clarity, increased predation, larger prey and low dissolved oxygen levels, these fish adapted their eyes, body shape, upper jaw and gills in a way that would be beneficial to the survival of the fish. These adaptive responses could be the result of phenotypic plasticity or genetically based changes such as natural selection or hybridization or a combination of these three mechanisms. This research showed that the Lake Victoria cichlids are able to adapt extremely fast which is likely to have contributed to their extreme fast adaptive radiation. Show less
Throughout history, climate change has been an important driving force behind human behaviour. This archaeological study seeks to understand the complex interrelations between that behaviour and... Show moreThroughout history, climate change has been an important driving force behind human behaviour. This archaeological study seeks to understand the complex interrelations between that behaviour and climatic fluctuations, focussing on how climate affected the social relations between neighbouring communities of occasionally differing nature. It is argued that developments in these relations will fall within a continuum between competition on one end and cooperation on the other. The adoption of a particular strategy depends on whether that strategy is advantageous to a community in terms of the maintenance of its well-being when faced with adverse climate change. This model will be applied to northern Mesopotamia between 3000 and 1600 BC. Local palaeoclimate proxy records demonstrate that aridity increased significantly during this period. Within this geographical, chronological, and climatic framework, this study looks at changes in settlement patterns as an indication of competition among sedentary agriculturalist communities, and the development of the Amorite ethnic identity as reflecting cooperation among sedentary and more mobile pastoralist communities. Show less
Rising atmospheric CO2 levels are predicted to have major consequences upon carbon cycle feedbacks and the overall functioning of terrestrial ecosystems. Photosynthetic activity and the structure... Show moreRising atmospheric CO2 levels are predicted to have major consequences upon carbon cycle feedbacks and the overall functioning of terrestrial ecosystems. Photosynthetic activity and the structure of terrestrial macrophytes is expected to change, but it remains uncertain how this will affect soil-borne communities dependent on plant-derived carbon, and their feedbacks on ecosystem function. Our main objective is to assess the impact of increased atmospheric carbon dioxide on microbial community dynamics in the rhizosphere. Using a controlled growth system, we examined the short-term and long-term impact of elevated atmospheric CO2 on soil-borne microbial communities by comparing belowground community responses associated with plants grown under ambient versus double ambient CO2 environments. Results on the structure and dynamics of broad and specific microbial groups provided insight into the plant-microbe interactions of the r hizosphere under elevated CO2. We also showed that the specific microbial groups are affected by elevated CO2 and demonstrate that presumably rhizo-competent bacteria and fungi are most highly affected by increased atmospheric CO2. These patterns were consistent with observed changes in the density of antibiotic production genes as well as changes in exudation patterns. The results demonstrate that elevated CO2 influenced different parts of the soil microbial community, but that the effects depend on the plant species and soil type. Pulse labelling studies demonstrates that elevated atmospheric CO2 increases translocation of plant-fixed carbon, via arbuscular mycorrhizal fungi (AMF), and that distinct microbial populations incorporate plant-derived carbon under different levels of atmospheric CO2. As opposed to simply increasing the activity of soil-borne microbes resident at ambient CO2 conditions, elevated atmospheric CO2 clearly selects for opportunistic plant-associated microbial communities, with a shift in dominant AMF species, as well as rhizosphere bacterial and fungal populations. These experiments also showed that AMF are the main conduit in the transfer of carbon between plants and soil. The microbial carbon dynamic model derived from our results provides a general framework for reappraising our view of carbon flow paths in soils and their effects on soil biodiversity under elevated atmospheric CO2 concentration. Show less
