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    Process disturbances in agricultural biogas production—causes, mechanisms and effects on the biogas microbiome: A review
    (Basel : MDPI AG, 2019) Theuerl, S.; Klang, J.; Prochnow, A.
    Disturbances of the anaerobic digestion process reduce the economic and environmental performance of biogas systems. A better understanding of the highly complex process is of crucial importance in order to avoid disturbances. This review defines process disturbances as significant changes in the functionality within the microbial community leading to unacceptable and severe decreases in biogas production and requiring an active counteraction to be overcome. The main types of process disturbances in agricultural biogas production are classified as unfavorable process temperatures, fluctuations in the availability of macro- and micronutrients (feedstock variability), overload of the microbial degradation potential, process-related accumulation of inhibiting metabolites such as hydrogen (H 2 ), ammonium/ammonia (NH 4 + /NH 3 ) or hydrogen sulphide (H 2 S) and inhibition by other organic and inorganic toxicants. Causes, mechanisms and effects on the biogas microbiome are discussed. The need for a knowledge-based microbiome management to ensure a stable and efficient production of biogas with low susceptibility to disturbances is derived and an outlook on potential future process monitoring and control by means of microbial indicators is provided.
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    The concerns of the young protesters are justified: A statement by Scientists for Future concerning the protests for more climate protection
    (München : Oekom Verl., 2019) Hagedorn, Gregor; Loew, Thomas; Seneviratne, Sonia I.; Lucht, Wolfgang; Beck, Marie-Luise; Hesse, Janina; Knutti, Reto; Quaschning, Volker; Schleimer, Jan-Hendrik; Mattauch, Linus; Breyer, Christian; Hübener, Heike; Kirchengast, Gottfried; Chodura, Alice; Clausen, Jens; Creutzig, Felix; Darbi, Marianne; Daub, Claus-Heinrich; Ekardt, Felix; Göpel, Maja; Hardt, Judith N.; Hertin, Julia; Hickler, Thomas; Köhncke, Arnulf; Köster, Stephan; Krohmer, Julia; Kromp-Kolb, Helga; Leinfelder, Reinhold; Mederake, Linda; Neuhaus, Michael; Rahmstorf, Stefan; Schmidt, Christine; Schneider, Christoph; Schneider, Gerhard; Seppelt, Ralf; Spindler, Uli; Springmann, Marco; Staab, Katharina; Stocker, Thomas F.; Steininger, Karl; Hirschhausen, Eckart von; Winter, Susanne; Wittau, Martin; Zens, Josef
    In March 2019, German-speaking scientists and scholars calling themselves Scientists for Future, published a statement in support of the youth protesters in Germany, Austria, and Switzerland (Fridays for Future, Klimastreik/Climate Strike), verifying the scientific evidence that the youth protestors refer to. In this article, they provide the full text of the statement, including the list of supporting facts (in both English and German) as well as an analysis of the results and impacts of the statement. Furthermore, they reflect on the challenges for scientists and scholars who feel a dual responsibility: on the one hand, to remain independent and politically neutral, and, on the other hand, to inform and warn societies of the dangers that lie ahead. © 2019 G. Hagedorn et al.; licensee oekom verlag.This Open Access article is published under the terms of the Creative Commons Attribution License CCBY4.0 (http://creativecommons.org/licenses/by/4.0).
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    Synthesizing plausible futures for biodiversity and ecosystem services in europe and central asia using scenario archetypes
    (Wolfville, Nova Scotia : Resilience Alliance, 2019) Harrison, Paula A.; Harmáčková, Zuzana V.; Karabulut, Armağan Aloe; Brotons, Lluis; Cantele, Matthew; Claudet, Joachim; Dunford, Robert W.; Guisan, Antoine; Holman, Ian P.; Jacobs, Sander; Kok, Kasper; Lobanova, Anastasia; Morán-Ordóñez, Alejandra; Pedde, Simona; Rixen, Christian; Santos-Martín, Fernando; Schlaepfer, Martin A.; Solidoro, Cosimo; Sonrel, Anthony; Hauck, Jennifer
    Scenarios are a useful tool to explore possible futures of social-ecological systems. The number of scenarios has increased dramatically over recent decades, with a large diversity in temporal and spatial scales, purposes, themes, development methods, and content. Scenario archetypes generically describe future developments and can be useful in meaningfully classifying scenarios, structuring and summarizing the overwhelming amount of information, and enabling scientific outputs to more effectively interface with decision-making frameworks. The Intergovernmental Platform for Biodiversity and Ecosystem Services (IPBES) faced this challenge and used scenario archetypes in its assessment of future interactions between nature and society. We describe the use of scenario archetypes in the IPBES Regional Assessment of Europe and Central Asia. Six scenario archetypes for the region are described in terms of their driver assumptions and impacts on nature (including biodiversity) and its contributions to people (including ecosystem services): Business-as-usual, economic optimism, regional competition, regional sustainability, global sustainable development, and inequality. The analysis shows that trade-offs between nature’s contributions to people are projected under different scenario archetypes. However, the means of resolving these trade-offs depend on differing political and societal value judgements within each scenario archetype. Scenarios that include proactive decision making on environmental issues, environmental management approaches that support multifunctionality, and mainstreaming environmental issues across sectors, are generally more successful in mitigating tradeoffs than isolated environmental policies. Furthermore, those scenario archetypes that focus on achieving a balanced supply of nature’s contributions to people and that incorporate a diversity of values are estimated to achieve more policy goals and targets, such as the UN Sustainable Development Goals and the Convention on Biological Diversity Aichi targets. The scenario archetypes approach is shown to be helpful in supporting science-policy dialogue for proactive decision making that anticipates change, mitigates undesirable trade-offs, and fosters societal transformation in pursuit of sustainable development. © 2019 by the author(s).
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    Pelagic amphipods in the eastern fram strait with continuing presence of Themisto compressa based on sediment trap time series
    (Frontiers Media S.A., 2019) Schröter, F.; Havermans, C.; Kraft, A.; Knüppel, N.; Beszczynska-Möller, A.; Bauerfeind, E.; Nöthig, E.-M.
    Pelagic amphipods represent a large fraction of organisms entering sediment traps as so-called "swimmers." These swimmers were sampled with sediment traps (~200-300 m water depth) with two mooring arrays deployed at two different positions in the Long-Term Ecological Research observatory HAUSGARTEN in the northeastern Fram Strait. This sampling allowed us to investigate amphipod year-round abundances and inter-annual trends from 2000 onward. In this study, newly analyzed data from a 3-years period (August 2011-June 2014) are presented, extending this long-term investigation. In our results, the species Themisto abyssorum, T. libellula, and T. compressa dominated the swimmer biomass, corroborating previous studies. The observed increase of amphipod abundances persisted in all three species, additionally implying that Themisto compressa maintained its population off Svalbard, which appeared for the first time here after a warm anomaly in 2004-2007. This study provides evidence for changes in amphipod community patterns that can mainly be attributed to growing abundances of T. compressa. Similarly, another hyperiid, Lanceola clausii, also increased in abundance over the investigated period. For T. libellula, almost no juvenile individuals were recorded in the sampling period 2013/14, even though juveniles of this species were common in earlier records. The three more years of observations clearly suggest that recently documented environmental shifts persist in the eastern Fram Strait. They also highlight the merit of using sediment trap time series to obtain year-round data sets needed to reveal processes and range shift dynamics in the pelagic system on a long-term basis.