Search Results

Now showing 1 - 10 of 26
  • Item
    Bioenergy for climate change mitigation: Scale and sustainability
    (Oxford : Wiley-Blackwell, 2021) Calvin, Katherine; Cowie, Annette; Berndes, Göran; Arneth, Almut; Cherubini, Francesco; Portugal‐Pereira, Joana; Grassi, Giacomo; House, Jo; Johnson, Francis X.; Popp, Alexander; Rounsevell, Mark; Slade, Raphael; Smith, Pete
    Many global climate change mitigation pathways presented in IPCC assessment reports rely heavily on the deployment of bioenergy, often used in conjunction with carbon capture and storage. We review the literature on bioenergy use for climate change mitigation, including studies that use top-down integrated assessment models or bottom-up modelling, and studies that do not rely on modelling. We summarize the state of knowledge concerning potential co-benefits and adverse side effects of bioenergy systems and discuss limitations of modelling studies used to analyse consequences of bioenergy expansion. The implications of bioenergy supply on mitigation and other sustainability criteria are context dependent and influenced by feedstock, management regime, climatic region, scale of deployment and how bioenergy alters energy systems and land use. Depending on previous land use, widespread deployment of monoculture plantations may contribute to mitigation but can cause negative impacts across a range of other sustainability criteria. Strategic integration of new biomass supply systems into existing agriculture and forest landscapes may result in less mitigation but can contribute positively to other sustainability objectives. There is considerable variation in evaluations of how sustainability challenges evolve as the scale of bioenergy deployment increases, due to limitations of existing models, and uncertainty over the future context with respect to the many variables that influence alternative uses of biomass and land. Integrative policies, coordinated institutions and improved governance mechanisms to enhance co-benefits and minimize adverse side effects can reduce the risks of large-scale deployment of bioenergy. Further, conservation and efficiency measures for energy, land and biomass can support greater flexibility in achieving climate change mitigation and adaptation.
  • Item
    LivWell: a sub-national Dataset on the Living Conditions of Women and their Well-being for 52 Countries
    (London : Nature Publ. Group, 2022) Belmin, Camille; Hoffmann, Roman; Elkasabi, Mahmoud; Pichler, Peter-Paul
    Data on women’s living conditions and socio-economic development are important for understanding and addressing the pronounced challenges and inequalities faced by women worldwide. While such information is increasingly available at the national level, comparable data at the sub-national level are missing. We here present the LivWell global longitudinal dataset, which includes a set of key indicators on women’s socio-economic status, health and well-being, access to basic services and demographic outcomes. It covers 447 regions in 52 countries and includes a total of 265 different indicators. The majority of these are based on 199 Demographic and Health Surveys (DHS) for the period 1990–2019 and are complemented by extensive information on socio-economic and climatic conditions in the respective regions. The resulting dataset offers various opportunities for policy-relevant research on gender inequality, inclusive development and demographic trends at the sub-national level.
  • Item
    Small-Signal Stability of Multi-Converter Infeed Power Grids with Symmetry
    (Basel : MDPI, 2021) Yu, Jiawei; Yang, Ziqian; Kurths, Jurgen; Zhan, Meng
    Traditional power systems have been gradually shifting to power-electronic-based ones, with more power electronic devices (including converters) incorporated recently. Faced with much more complicated dynamics, it is a great challenge to uncover its physical mechanisms for system stability and/or instability (oscillation). In this paper, we first establish a nonlinear model of a multi-converter power system within the DC-link voltage timescale, from the first principle. Then, we obtain a linearized model with the associated characteristic matrix, whose eigenvalues determine the system stability, and finally get independent subsystems by using symmetry approximation conditions under the assumptions that all converters’ parameters and their susceptance to the infinite bus (Bg) are identical. Based on these mathematical analyses, we find that the whole system can be decomposed into several equivalent single-converter systems and its small-signal stability is solely determined by a simple converter system connected to an infinite bus under the same susceptance Bg. These results of large-scale multi-converter analysis help to understand the power-electronic-based power system dynamics, such as renewable energy integration. As well, they are expected to stimulate broad interests among researchers in the fields of network dynamics theory and applications.
  • Item
    The Economic Impact of Exchanging Breeding Material: Assessing Winter Wheat Production in Germany
    (Lausanne : Frontiers Media, 2020) Lüttringhaus, Sophia; Gornott, Christoph; Wittkop, Benjamin; Noleppa, Steffen; Lotze-Campen, Hermann
    Climate change impacts imply that the stabilization and improvement of agricultural production systems using technological innovations has become vital. Improvements in plant breeding are integral to such innovations. In the context of German crop breeding programs, the economic impact of exchanging genetic material has yet to be determined. To this end, we analyze in this impact assessment the economic effects on German winter wheat production that are attributable to exchanging parental material amongst breeders in the breeding process. This exchange is supported by the breeders’ exemption, which is an integral part of the German plant variety protection legislation. It ensures that breeders can freely use licensed varieties created by other breeders for their own breeding activities and aims to speed up the development of improved varieties. For our analysis, we created a unique data set that combines variety-specific grain yield, adoption, and pedigree information of 133 winter wheat varieties. We determined the parental pedigree of each variety to see if a variety was created by interbreeding varieties that are internal or external to its specific breeder. Our study is the first that analyzes the economic impact of exchanging genetic material in German breeding programs. We found that more than 90 % of the tested varieties were bred with exchanged parental material, whereby the majority had two external parents. Also, these varieties were planted on an 8.5 times larger area than the varieties that were bred with two internal parents. Due to lower adoption, these only contributed 11 % to the overall winter wheat production in Germany, even though they yielded more. We used an economic surplus model to measure the benefits of exchanging parental breeding material on German winter wheat production. This resulted in an overall estimated economic surplus of 19.2 to 22.0 billion EUR from production year 1972 to 2018. This implies tremendous returns to using the breeder’s exemption, which, from an economic perspective, is almost cost-free for the breeder. We conclude that the exchange of breeding material contributes to improving Germany’s agricultural production and fosters the development of climate-resilient production systems and global food security. © Copyright © 2020 Lüttringhaus, Gornott, Wittkop, Noleppa and Lotze-Campen.
  • Item
    Significant increase in natural disturbance impacts on European forests since 1950
    (Oxford [u.a.] : Blackwell Science, 2022) Patacca, Marco; Lindner, Marcus; Lucas‐Borja, Manuel Esteban; Cordonnier, Thomas; Fidej, Gal; Gardiner, Barry; Hauf, Ylva; Jasinevičius, Gediminas; Labonne, Sophie; Linkevičius, Edgaras; Mahnken, Mats; Milanovic, Slobodan; Nabuurs, Gert‐Jan; Nagel, Thomas A.; Nikinmaa, Laura; Panyatov, Momchil; Bercak, Roman; Seidl, Rupert; Ostrogović Sever, Masa Zorana; Socha, Jaroslaw; Thom, Dominik; Vuletic, Dijana; Zudin, Sergey; Schelhaas, Mart‐Jan
    Over the last decades, the natural disturbance is increasingly putting pressure on European forests. Shifts in disturbance regimes may compromise forest functioning and the continuous provisioning of ecosystem services to society, including their climate change mitigation potential. Although forests are central to many European policies, we lack the long-term empirical data needed for thoroughly understanding disturbance dynamics, modeling them, and developing adaptive management strategies. Here, we present a unique database of >170,000 records of ground-based natural disturbance observations in European forests from 1950 to 2019. Reported data confirm a significant increase in forest disturbance in 34 European countries, causing on an average of 43.8 million m3 of disturbed timber volume per year over the 70-year study period. This value is likely a conservative estimate due to under-reporting, especially of small-scale disturbances. We used machine learning techniques for assessing the magnitude of unreported disturbances, which are estimated to be between 8.6 and 18.3 million m3/year. In the last 20 years, disturbances on average accounted for 16% of the mean annual harvest in Europe. Wind was the most important disturbance agent over the study period (46% of total damage), followed by fire (24%) and bark beetles (17%). Bark beetle disturbance doubled its share of the total damage in the last 20 years. Forest disturbances can profoundly impact ecosystem services (e.g., climate change mitigation), affect regional forest resource provisioning and consequently disrupt long-term management planning objectives and timber markets. We conclude that adaptation to changing disturbance regimes must be placed at the core of the European forest management and policy debate. Furthermore, a coherent and homogeneous monitoring system of natural disturbances is urgently needed in Europe, to better observe and respond to the ongoing changes in forest disturbance regimes.
  • Item
    Simulating functional diversity of European natural forests along climatic gradients
    (Oxford [u.a.] : Wiley-Blackwell, 2020) Thonicke, Kirsten; Billing, Maik; von Bloh, Werner; Sakschewski, Boris; Niinemets, Ülo; Peñuelas, Josep; Cornelissen, J. Hans C.; Onoda, Yusuke; van Bodegom, Peter; Schaepman, Michael E.; Schneider, Fabian D.; Walz, Ariane
    Aim: We analyse how functional diversity (FD) varies across European natural forests to understand the effects of environmental and competitive filtering on plant trait distribution. Location: Forest ecosystems in Europe from 11°W to 36°E and 29.5°N to 62°N. Taxon: Pinaceae, Fagaceae and Betulaceae, Oleaceae, Tiliaceae, Aceraceae, Leguminosae (unspecific). Methods: We adopted the existing Dynamic Global Vegetation Model Lund-Potsdam-Jena managed Land of flexible individual traits (LPJmL-FIT) for Europe by eliminating both bioclimatic limits of plant functional types (PFTs) and replacing prescribed values of functional traits for PFTs with emergent values under influence of environmental filtering and competition. We quantified functional richness (FR), functional divergence (FDv) and functional evenness (FE) in representative selected sites and at Pan-European scale resulting from simulated functional and structural trait combinations of individual trees. While FR quantifies the amount of occupied trait space, FDv and FE describe the distribution and abundance of trait combinations, respectively, in a multidimensional trait space. Results: Lund-Potsdam-Jena managed Land of flexible individual traits reproduces spatial PFTs and local trait distributions and agrees well with observed productivity, biomass and tree height of European natural forests. The observed site-specific trait distributions and spatial gradients of traits of the leaf- and stem-resource economics spectra coincide with environmental filtering and the competition for light and water in environments with strong abiotic stress. Where deciduous and needle-leaved trees co-occur, for example, in boreal and mountainous forests, the potential niche space is wide (high FR), and extreme ends in the niche space are occupied (high FDv). We find high FDv in Mediterranean forests where drought increasingly limits tree growth, thus niche differentiation becomes more important. FDv decreases in temperate forests where a cold climate increasingly limits growth efficiency of broad-leaved summer green trees, thus reducing the importance of competitive exclusion. Highest FE was simulated in wet Atlantic and southern Europe which indicated relatively even niche occupation and thus high resource-use efficiency. Main Conclusions: We find FD resulting from both environmental and competitive filtering. Pan-European FR, FDv and FE demonstrate the influence of climate gradients and intra- and inter-PFT competition. The indices underline a generally high FD of natural forests in Europe. Co-existence of functionally diverse trees across PFTs emerges from alternative (life-history) strategies, disturbance and tree demography. © 2020 John Wiley & Sons Ltd
  • Item
    Sleep as a Novel Biomarker and a Promising Therapeutic Target for Cerebral Small Vessel Disease: A Review Focusing on Alzheimer’s Disease and the Blood-Brain Barrier
    (Basel : Molecular Diversity Preservation International, 2020) Semyachkina-Glushkovskaya, Oxana; Postnov, Dmitry; Penzel, Thomas; Kurths, Jürgen
    Cerebral small vessel disease (CSVD) is a leading cause of cognitive decline in elderly people and development of Alzheimer’s disease (AD). Blood–brain barrier (BBB) leakage is a key pathophysiological mechanism of amyloidal CSVD. Sleep plays a crucial role in keeping health of the central nervous system and in resistance to CSVD. The deficit of sleep contributes to accumulation of metabolites and toxins such as beta-amyloid in the brain and can lead to BBB disruption. Currently, sleep is considered as an important informative platform for diagnosis and therapy of AD. However, there are no effective methods for extracting of diagnostic information from sleep characteristics. In this review, we show strong evidence that slow wave activity (SWA) (0–0.5 Hz) during deep sleep reflects glymphatic pathology, the BBB leakage and memory deficit in AD. We also discuss that diagnostic and therapeutic targeting of SWA in AD might lead to be a novel era in effective therapy of AD. Moreover, we demonstrate that SWA can be pioneering non-invasive and bed–side technology for express diagnosis of the BBB permeability. Finally, we review the novel data about the methods of detection and enhancement of SWA that can be biomarker and a promising therapy of amyloidal CSVD and CSVD associated with the BBB disorders. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
  • Item
    Impact of extreme weather conditions on European crop production in 2018
    (London : Royal Society, 2020) Beillouin, Damien; Schauberger, Bernhard; Bastos, Ana; Ciais, Phillipe; Makowski, David
    Extreme weather increases the risk of large-scale crop failure. The mechanisms involved are complex and intertwined, hence undermining the identification of simple adaptation levers to help improve the resilience of agricultural production. Based on more than 82 000 yield data reported at the regional level in 17 European countries, we assess how climate affected the yields of nine crop species. Using machine learning models, we analyzed historical yield data since 1901 and then focus on 2018, which has experienced a multiplicity and a diversity of atypical extreme climatic conditions. Machine learning models explain up to 65% of historical yield anomalies. We find that both extremes in temperature and precipitation are associated with negative yield anomalies, but with varying impacts in different parts of Europe. In 2018, Northern and Eastern Europe experienced multiple and simultaneous crop failures - among the highest observed in recent decades. These yield losses were associated with extremely low rainfalls in combination with high temperatures between March and August 2018. However, the higher than usual yields recorded in Southern Europe - caused by favourable spring rainfall conditions - nearly offset the large decrease in Northern European crop production. Our results outline the importance of considering single and compound climate extremes to analyse the causes of yield losses in Europe. We found no clear upward or downward trend in the frequency of extreme yield losses for any of the considered crops between 1990 and 2018. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'. © 2020 The Authors.
  • Item
    Advances in Understanding and Managing Catastrophic Ecosystem Shifts in Mediterranean Ecosystems
    (Lausanne : Frontiers Media, 2020) van den Elsen, Erik; Stringer, Lindsay C.; De Ita, Cecilia; Hessel, Rudi; Kéfi, Sonia; Schneider, Florian D.; Bautista, Susana; Mayor, Angeles G.; Baudena, Mara; Rietkerk, Max; Valdecantos, Alejandro; Vallejo, Victoriano R.; Geeson, Nichola; Brandt, C. Jane; Fleskens, Luuk; Hemerik, Lia; Panagos, Panos; Valente, Sandra; Keizer, Jan J.; Schwilch, Gudrun; Jucker Riva, Matteo; Sietz, Diana; Christoforou, Michalakis; Hadjimitsis, Diofantos G.; Papoutsa, Christiana; Quaranta, Giovanni; Salvia, Rosanna; Tsanis, Ioannis K.; Daliakopoulos, Ioannis; Claringbould, Heleen; de Ruiter, Peter C.
    One of the most challenging issues in Mediterranean ecosystems to date has been to understand the emergence of discontinuous changes or catastrophic shifts. In the era of the 2030 Sustainable Development Goals, which encompass ideas around Land Degradation Neutrality, advancing this understanding has become even more critical and urgent. The aim of this paper is to synthesize insights into the drivers, processes and management of catastrophic shifts to highlight ways forward for the management of Mediterranean ecosystems. We use a multidisciplinary approach that extends beyond the typical single site, single scale, single approach studies in the current literature. We link applied and theoretical ecology at multiple scales with analyses and modeling of human–environment–climate relations and stakeholder engagement in six field sites in Mediterranean ecosystems to address three key questions: How do major degradation drivers affect ecosystem functioning and services in Mediterranean ecosystems? What processes happen in the soil and vegetation during a catastrophic shift? How can management of vulnerable ecosystems be optimized using these findings? Drawing together the findings from the use of different approaches allows us to address the whole pipeline of changes from drivers through to action. We highlight ways to assess ecosystem vulnerability that can help to prevent ecosystem shifts to undesirable states; identify cost-effective management measures that align with the vision and plans of land users; and evaluate the timing of these measures to enable optimization of their application before thresholds are reached. Such a multidisciplinary approach enables improved identification of early warning signals for discontinuous changes informing more timely and cost-effective management, allowing anticipation of, adaptation to, or even prevention of, undesirable catastrophic ecosystem shifts. © Copyright © 2020 van den Elsen, Stringer, De Ita, Hessel, Kéfi, Schneider, Bautista, Mayor, Baudena, Rietkerk, Valdecantos, Vallejo, Geeson, Brandt, Fleskens, Hemerik, Panagos, Valente, Keizer, Schwilch, Jucker Riva, Sietz, Christoforou, Hadjimitsis, Papoutsa, Quaranta, Salvia, Tsanis, Daliakopoulos, Claringbould and de Ruiter.
  • Item
    Challenges in producing policy-relevant global scenarios of biodiversity and ecosystem services
    (Amsterdam : Elsevier, 2020) Rosa, Isabel M.D.; Purvis, Andy; Alkemade, Rob; Chaplin-Kramer, Rebecca; Ferrier, Simon; Guerra, Carlos A.; Hurtt, George; Kim, HyeJin; Leadley, Paul; Martins, Inês S.; Popp, Alexander; Schipper, Aafke M.; van Vuuren, Detlef; Pereira, Henrique M.
    Scenario-based modelling is a powerful tool to describe relationships between plausible trajectories of drivers, possible policy interventions, and impacts on biodiversity and ecosystem services. Model inter-comparisons are key in quantifying uncertainties and identifying avenues for model improvement but have been missing among the global biodiversity and ecosystem services modelling communities. The biodiversity and ecosystem services scenario-based inter-model comparison (BES-SIM) aims to fill this gap. We used global land-use and climate projections to simulate possible future impacts on terrestrial biodiversity and ecosystem services using a variety of models and a range of harmonized metrics. The goal of this paper is to reflect on the steps taken in BES-SIM, identify remaining methodological challenges, and suggest pathways for improvement. We identified five major groups of challenges; the need to: 1) better account for the role of nature in future human development storylines; 2) improve the representation of drivers in the scenarios by increasing the resolution (temporal, spatial and thematic) of land-use as key driver of biodiversity change and including additional relevant drivers; 3) explicitly integrate species- and trait-level biodiversity in ecosystem services models; 4) expand the coverage of the multiple dimensions of biodiversity and ecosystem services; and finally, 5) incorporate time-series or one-off historical data in the calibration and validation of biodiversity and ecosystem services models. Addressing these challenges would allow the development of more integrated global projections of biodiversity and ecosystem services, thereby improving their policy relevance in supporting the interlinked international conservation and sustainable development agendas. © 2019 The Authors