@phdthesis{Veh2019, author = {Veh, Georg}, title = {Outburst floods from moraine-dammed lakes in the Himalayas}, doi = {10.25932/publishup-43607}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436071}, school = {Universit{\"a}t Potsdam}, pages = {124}, year = {2019}, abstract = {The Himalayas are a region that is most dependent, but also frequently prone to hazards from changing meltwater resources. This mountain belt hosts the highest mountain peaks on earth, has the largest reserve of ice outside the polar regions, and is home to a rapidly growing population in recent decades. One source of hazard has attracted scientific research in particular in the past two decades: glacial lake outburst floods (GLOFs) occurred rarely, but mostly with fatal and catastrophic consequences for downstream communities and infrastructure. Such GLOFs can suddenly release several million cubic meters of water from naturally impounded meltwater lakes. Glacial lakes have grown in number and size by ongoing glacial mass losses in the Himalayas. Theory holds that enhanced meltwater production may increase GLOF frequency, but has never been tested so far. The key challenge to test this notion are the high altitudes of >4000 m, at which lakes occur, making field work impractical. Moreover, flood waves can attenuate rapidly in mountain channels downstream, so that many GLOFs have likely gone unnoticed in past decades. Our knowledge on GLOFs is hence likely biased towards larger, destructive cases, which challenges a detailed quantification of their frequency and their response to atmospheric warming. Robustly quantifying the magnitude and frequency of GLOFs is essential for risk assessment and management along mountain rivers, not least to implement their return periods in building design codes. Motivated by this limited knowledge of GLOF frequency and hazard, I developed an algorithm that efficiently detects GLOFs from satellite images. In essence, this algorithm classifies land cover in 30 years (~1988-2017) of continuously recorded Landsat images over the Himalayas, and calculates likelihoods for rapidly shrinking water bodies in the stack of land cover images. I visually assessed such detected tell-tale sites for sediment fans in the river channel downstream, a second key diagnostic of GLOFs. Rigorous tests and validation with known cases from roughly 10\% of the Himalayas suggested that this algorithm is robust against frequent image noise, and hence capable to identify previously unknown GLOFs. Extending the search radius to the entire Himalayan mountain range revealed some 22 newly detected GLOFs. I thus more than doubled the existing GLOF count from 16 previously known cases since 1988, and found a dominant cluster of GLOFs in the Central and Eastern Himalayas (Bhutan and Eastern Nepal), compared to the rarer affected ranges in the North. Yet, the total of 38 GLOFs showed no change in the annual frequency, so that the activity of GLOFs per unit glacial lake area has decreased in the past 30 years. I discussed possible drivers for this finding, but left a further attribution to distinct GLOF-triggering mechanisms open to future research. This updated GLOF frequency was the key input for assessing GLOF hazard for the entire Himalayan mountain belt and several subregions. I used standard definitions in flood hydrology, describing hazard as the annual exceedance probability of a given flood peak discharge [m3 s-1] or larger at the breach location. I coupled the empirical frequency of GLOFs per region to simulations of physically plausible peak discharges from all existing ~5,000 lakes in the Himalayas. Using an extreme-value model, I could hence calculate flood return periods. I found that the contemporary 100-year GLOF discharge (the flood level that is reached or exceeded on average once in 100 years) is 20,600+2,200/-2,300 m3 s-1 for the entire Himalayas. Given the spatial and temporal distribution of historic GLOFs, contemporary GLOF hazard is highest in the Eastern Himalayas, and lower for regions with rarer GLOF abundance. I also calculated GLOF hazard for some 9,500 overdeepenings, which could expose and fill with water, if all Himalayan glaciers have melted eventually. Assuming that the current GLOF rate remains unchanged, the 100-year GLOF discharge could double (41,700+5,500/-4,700 m3 s-1), while the regional GLOF hazard may increase largest in the Karakoram. To conclude, these three stages-from GLOF detection, to analysing their frequency and estimating regional GLOF hazard-provide a framework for modern GLOF hazard assessment. Given the rapidly growing population, infrastructure, and hydropower projects in the Himalayas, this thesis assists in quantifying the purely climate-driven contribution to hazard and risk from GLOFs.}, language = {en} } @article{TabaresJimenezZimmermannDietzeetal.2019, author = {Tabares Jimenez, Ximena del Carmen and Zimmermann, Heike Hildegard and Dietze, Elisabeth and Ratzmann, Gregor and Belz, Lukas and Vieth-Hillebrand, Andrea and Dupont, Lydie and Wilkes, Heinz and Mapani, Benjamin and Herzschuh, Ulrike}, title = {Vegetation state changes in the course of shrub encroachment in an African savanna since about 1850 CE and their potential drivers}, series = {Ecology and evolution}, volume = {10}, journal = {Ecology and evolution}, number = {2}, publisher = {Wiley}, address = {Hoboken}, issn = {2045-7758}, doi = {10.1002/ece3.5955}, pages = {962 -- 979}, year = {2019}, abstract = {Shrub encroachment has far-reaching ecological and economic consequences in many ecosystems worldwide. Yet, compositional changes associated with shrub encroachment are often overlooked despite having important effects on ecosystem functioning. We document the compositional change and potential drivers for a northern Namibian Combretum woodland transitioning into a Terminalia shrubland. We use a multiproxy record (pollen, sedimentary ancient DNA, biomarkers, compound-specific carbon (delta C-13) and deuterium (delta D) isotopes, bulk carbon isotopes (delta(13)Corg), grain size, geochemical properties) from Lake Otjikoto at high taxonomical and temporal resolution. We provide evidence that state changes in semiarid environments may occur on a scale of one century and that transitions between stable states can span around 80 years and are characterized by a unique vegetation composition. We demonstrate that the current grass/woody ratio is exceptional for the last 170 years, as supported by n-alkane distributions and the delta C-13 and delta(13)Corg records. Comparing vegetation records to environmental proxy data and census data, we infer a complex network of global and local drivers of vegetation change. While our delta D record suggests physiological adaptations of woody species to higher atmospheric pCO(2) concentration and drought, our vegetation records reflect the impact of broad-scale logging for the mining industry, and the macrocharcoal record suggests a decrease in fire activity associated with the intensification of farming. Impact of selective grazing is reflected by changes in abundance and taxonomical composition of grasses and by an increase of nonpalatable and trampling-resistant taxa. In addition, grain-size and spore records suggest changes in the erodibility of soils because of reduced grass cover. Synthesis. We conclude that transitions to an encroached savanna state are supported by gradual environmental changes induced by management strategies, which affected the resilience of savanna ecosystems. In addition, feedback mechanisms that reflect the interplay between management legacies and climate change maintain the encroached state.}, language = {en} } @article{SchwarzerJoshi2019, author = {Schwarzer, Christian and Joshi, Jasmin Radha}, title = {Ecotypic differentiation, hybridization and clonality facilitate the persistence of a cold-adapted sedge in European bogs}, series = {Biological journal of the Linnean Society : a journal of evolution}, volume = {128}, journal = {Biological journal of the Linnean Society : a journal of evolution}, number = {4}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0024-4066}, doi = {10.1093/biolinnean/blz141}, pages = {909 -- 925}, year = {2019}, abstract = {Recent research has shown that many cold-adapted species survived the last glacial maximum (LGM) in northern refugia. Whether this evolutionary history has had consequences for their genetic diversity and adaptive potential remains unknown. We sampled 14 populations of Carex limosa, a sedge specialized to bog ecosystems, along a latitudinal gradient from its Scandinavian core to the southern lowland range-margin in Germany. Using microsatellite and experimental common-garden data, we evaluated the impacts of global climate change along this gradient and assessed the conservation status of the southern marginal populations. Microsatellite data revealed two highly distinct genetic groups and hybrid individuals. In our common-garden experiment, the two groups showed divergent responses to increased nitrogen/phosphorus (N/P) availability, suggesting ecotypic differentiation. Each group formed genetically uniform populations at both northern and southern sampling areas. Mixed populations occurred throughout our sampling area, an area that was entirely glaciated during the LGM. The fragmented distribution implies allopatric divergence at geographically separated refugia that putatively differed in N/P availability. Molecular data and an observed low hybrid fecundity indicate the importance of clonal reproduction for hybrid populations. At the southern range-margin, however, all populations showed effects of clonality, lowered fecundity and low competitiveness, suggesting abiotic and biotic constraints to population persistence.}, language = {en} } @article{SchneiderWalsh2019, author = {Schneider, Birgit and Walsh, Lynda}, title = {The politics of zoom}, series = {Geo: Geography and Environment}, volume = {6}, journal = {Geo: Geography and Environment}, number = {1}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {2054-4049}, doi = {10.1002/geo2.70}, pages = {11}, year = {2019}, abstract = {Following the mandate in the Paris Agreement for signatories to provide "climate services" to their constituents, "downscaled" climate visualizations are proliferating. But the process of downscaling climate visualizations does not neutralize the political problems with their synoptic global sources—namely, their failure to empower communities to take action and their replication of neoliberal paradigms of globalization. In this study we examine these problems as they apply to interactive climate-visualization platforms, which allow their users to localize global climate information to support local political action. By scrutinizing the political implications of the "zoom" tool from the perspective of media studies and rhetoric, we add to perspectives of cultural cartography on the issue of scaling from our fields. Namely, we break down the cinematic trope of "zooming" to reveal how it imports the political problems of synopticism to the level of individual communities. As a potential antidote to the politics of zoom, we recommend a downscaling strategy of connectivity, which associates rather than reduces situated views of climate to global ones.}, language = {en} } @misc{SchneiderWalsh2019, author = {Schneider, Birgit and Walsh, Lynda}, title = {The politics of zoom}, series = {Postprints der Universit{\"a}t Potsdam Philosophische Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Philosophische Reihe}, number = {159}, issn = {1866-8380}, doi = {10.25932/publishup-42481}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-424819}, year = {2019}, abstract = {Following the mandate in the Paris Agreement for signatories to provide "climate services" to their constituents, "downscaled" climate visualizations are proliferating. But the process of downscaling climate visualizations does not neutralize the political problems with their synoptic global sources—namely, their failure to empower communities to take action and their replication of neoliberal paradigms of globalization. In this study we examine these problems as they apply to interactive climate-visualization platforms, which allow their users to localize global climate information to support local political action. By scrutinizing the political implications of the "zoom" tool from the perspective of media studies and rhetoric, we add to perspectives of cultural cartography on the issue of scaling from our fields. Namely, we break down the cinematic trope of "zooming" to reveal how it imports the political problems of synopticism to the level of individual communities. As a potential antidote to the politics of zoom, we recommend a downscaling strategy of connectivity, which associates rather than reduces situated views of climate to global ones.}, language = {en} } @phdthesis{RomeroMujalli2019, author = {Romero Mujalli, Daniel}, title = {Ecological modeling of adaptive evolutionary responses to rapid climate change}, doi = {10.25932/publishup-43062}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-430627}, school = {Universit{\"a}t Potsdam}, pages = {167}, year = {2019}, abstract = {A contemporary challenge in Ecology and Evolutionary Biology is to anticipate the fate of populations of organisms in the context of a changing world. Climate change and landscape changes due to anthropic activities have been of major concern in the contemporary history. Organisms facing these threats are expected to respond by local adaptation (i.e., genetic changes or phenotypic plasticity) or by shifting their distributional range (migration). However, there are limits to their responses. For example, isolated populations will have more difficulties in developing adaptive innovations by means of genetic changes than interconnected metapopulations. Similarly, the topography of the environment can limit dispersal opportunities for crawling organisms as compared to those that rely on wind. Thus, populations of species with different life history strategy may differ in their ability to cope with changing environmental conditions. However, depending on the taxon, empirical studies investigating organisms' responses to environmental change may become too complex, long and expensive; plus, complications arising from dealing with endangered species. In consequence, eco-evolutionary modeling offers an opportunity to overcome these limitations and complement empirical studies, understand the action and limitations of underlying mechanisms, and project into possible future scenarios. In this work I take a modeling approach and investigate the effect and relative importance of evolutionary mechanisms (including phenotypic plasticity) on the ability for local adaptation of populations with different life strategy experiencing climate change scenarios. For this, I performed a review on the state of the art of eco-evolutionary Individual-Based Models (IBMs) and identify gaps for future research. Then, I used the results from the review to develop an eco-evolutionary individual-based modeling tool to study the role of genetic and plastic mechanisms in promoting local adaption of populations of organisms with different life strategies experiencing scenarios of climate change and environmental stochasticity. The environment was simulated through a climate variable (e.g., temperature) defining a phenotypic optimum moving at a given rate of change. The rate of change was changed to simulate different scenarios of climate change (no change, slow, medium, rapid climate change). Several scenarios of stochastic noise color resembling different climatic conditions were explored. Results show that populations of sexual species will rely mainly on standing genetic variation and phenotypic plasticity for local adaptation. Population of species with relatively slow growth rate (e.g., large mammals) - especially those of small size - are the most vulnerable, particularly if their plasticity is limited (i.e., specialist species). In addition, whenever organisms from these populations are capable of adaptive plasticity, they can buffer fitness losses in reddish climatic conditions. Likewise, whenever they can adjust their plastic response (e.g., bed-hedging strategy) they will cope with bluish environmental conditions as well. In contrast, life strategies of high fecundity can rely on non-adaptive plasticity for their local adaptation to novel environmental conditions, unless the rate of change is too rapid. A recommended management measure is to guarantee interconnection of isolated populations into metapopulations, such that the supply of useful genetic variation can be increased, and, at the same time, provide them with movement opportunities to follow their preferred niche, when local adaptation becomes problematic. This is particularly important for bluish and reddish climatic conditions, when the rate of change is slow, or for any climatic condition when the level of stress (rate of change) is relatively high.}, language = {en} } @article{Mielke2019, author = {Mielke, Jahel}, title = {Signals for 2 degrees C}, series = {Journal of Sustainable Finance \& Investment}, volume = {9}, journal = {Journal of Sustainable Finance \& Investment}, number = {2}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {2043-0795}, doi = {10.1080/20430795.2018.1528809}, pages = {87 -- 115}, year = {2019}, abstract = {The targets of the Paris Agreement make it necessary to redirect finance flows towards sustainable, low-carbon infrastructures and technologies. Currently, the potential of institutional investors to help finance this transition is widely discussed. Thus, this paper takes a closer look at influence factors for green investment decisions of large European insurance companies. With a mix of qualitative and quantitative methods, the importance of policy, market and civil society signals is evaluated. In summary, respondents favor measures that promote green investment, such as feed-in tariffs or adjustments of capital charges for green assets, over ones that make carbon-intensive investments less attractive, such as the phase-out of fossil fuel subsidies or a carbon price. While investors currently see a low impact of the carbon price, they rank a substantial reform as an important signal for the future. Respondents also emphasize that policy signals have to be coherent and credible to coordinate expectations.}, language = {en} } @article{KahlLenhardJoshi2019, author = {Kahl, Sandra M. and Lenhard, Michael and Joshi, Jasmin Radha}, title = {Compensatory mechanisms to climate change in the widely distributed species Silene vulgaris}, series = {The journal of ecology}, volume = {107}, journal = {The journal of ecology}, number = {4}, publisher = {Wiley}, address = {Hoboken}, issn = {0022-0477}, doi = {10.1111/1365-2745.13133}, pages = {1918 -- 1930}, year = {2019}, abstract = {The adaptation of plants to future climatic conditions is crucial for their survival. Not surprisingly, phenotypic responses to climate change have already been observed in many plant populations. These responses may be due to evolutionary adaptive changes or phenotypic plasticity. Especially plant species with a wide geographic range are either expected to show genetic differentiation in response to differing climate conditions or to have a high phenotypic plasticity. We investigated phenotypic responses and plasticity as an estimate of the adaptive potential in the widespread species Silene vulgaris. In a greenhouse experiment, 25 European populations covering a geographic range from the Canary Islands to Sweden were exposed to three experimental precipitation and two temperature regimes mimicking a possible climate-change scenario for central Europe. We hypothesized that southern populations have a better performance under high temperature and drought conditions, as they are already adapted to a comparable environment. We found that our treatments significantly influenced the plants, but did not reveal a latitudinal difference in response to climate treatments for most plant traits. Only flower number showed a stronger plasticity in northern European populations (e.g. Swedish populations) where numbers decreased more drastically with increased temperature and decreased precipitation treatment. Synthesis. The significant treatment response in Silene vulgaris, independent of population origin - except for the number of flowers produced - suggests a high degree of universal phenotypic plasticity in this widely distributed species. This reflects the likely adaptation strategy of the species and forms the basis for a successful survival strategy during upcoming climatic changes. However, as flower number, a strongly fitness-related trait, decreased more strongly in northern populations under a climate-change scenario, there might be limits to adaptation even in this widespread, plastic species.}, language = {en} } @phdthesis{Hornick2019, author = {Hornick, Thomas}, title = {Impact of climate change effects on diversity and function of pelagic heterotrophic bacteria studied in large-scale mesocosm facilities}, doi = {10.25932/publishup-42893}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-428936}, school = {Universit{\"a}t Potsdam}, pages = {199}, year = {2019}, abstract = {Seit der Industriellen Revolution steigt die Konzentration von Kohlenstoffdioxid (CO2) und anderen Treibhausgasen in der Erdatmosph{\"a}re stetig an, wodurch wesentliche Prozesse im Erdsystem beeinflusst werden. Dies wird mit dem Begriff „Klimawandel" umschrieben. Aquatische {\"O}kosysteme sind sehr stark davon betroffen, da sie als Integral vieler Prozesse in einer Landschaft fungieren. Ziel dieser Doktorarbeit war zu bestimmen, wie verschiedene Auswirkungen des Klimawandels die Gemeinschaftsstruktur und Aktivit{\"a}t von heterotrophen Bakterien in Gew{\"a}ssern ver{\"a}ndert, welche eine zentrale Rolle bei biogeochemischen Prozessen einnehmen. Diese Arbeit konzentriert sich auf zwei Aspekte des Klimawandels: (1) Ozeane nehmen einen Großteil des atmosph{\"a}rischen CO2 auf, welches im Meerwasser das chemische Gleichgewicht des Karbonatsystems verschiebt („Ozeanversauerung"). (2) Durch kontinuierlichen Anstieg der Erdoberfl{\"a}chentemperatur werden Ver{\"a}nderungen im Klimasystem der Erde vorhergesagt, welche u. a. die H{\"a}ufigkeit und Heftigkeit von episodischen Wetterereignissen (z.B. St{\"u}rme) verst{\"a}rken wird. Insbesondere Sommer-St{\"u}rme sind dabei in der Lage die sommerliche Temperaturschichtung der Wassers{\"a}ule in Seen zu zerst{\"o}ren. Beide Effekte des Klimawandels k{\"o}nnen weitreichende Auswirkungen auf Wasserchemie/-physik sowie die Verteilung von Organismen haben, was mittels Mesokosmen simuliert wurde. Dabei untersuchten wir den Einfluss der Ozeanversauerung auf heterotrophe bakterielle Prozesse in der Ostsee bei geringen Konzentrationen an gel{\"o}sten N{\"a}hrstoffen. Unsere Ergebnisse zeigen, dass Ozeanversauerungseffekte in Kombination mit N{\"a}hrstofflimitation indirekt das Wachstum von heterotrophen Bakterien durch ver{\"a}nderte trophische Interaktionen beeinflussen k{\"o}nnen und potentiell zu einer Erh{\"o}hung der Autotrophie des {\"O}kosystems f{\"u}hren. In einer weiteren Studie analysierten wir, wie Ozeanversauerung die Umsetzung und Qualit{\"a}t gel{\"o}sten organischen Materials (DOM) durch heterotrophe Bakterien beeinflussen kann. Die Ergebnisse weisen jedoch darauf hin, dass {\"A}nderungen in der DOM-Qualit{\"a}t durch heterotrophe bakterielle Prozesse mit zunehmender Ozeanversauerung unwahrscheinlich sind. Desweiteren wurde der Einfluss eines starken Sommer-Sturmes auf den stratifizierten, oligotroph-mesotrophen Stechlinsee simuliert. Mittels oberfl{\"a}chlicher Durchmischung in Mesokosmen wurde die bestehende Thermokline zerst{\"o}rt und die durchmischte Oberfl{\"a}chenwasserschicht vergr{\"o}ßert. Dies {\"a}nderte die physikalischen und chemischen Gradienten innerhalb der Wassers{\"a}ule. Effekte der Einmischung von Tiefenwasser {\"a}nderten in der Folge die Zusammensetzung der bakteriellen Gemeinschaftsstruktur und stimulierten das Wachstum filament{\"o}ser Cyanobakterien, die zu einer Cyanobakterien-Bl{\"u}te f{\"u}hrte und so maßgeblich die metabolischen Prozesse von heterotrophen Bakterien bestimmte. Unsere Studie gibt ein mechanistisches Verst{\"a}ndnis, wie Sommer-St{\"u}rme bakterielle Gemeinschaften und Prozesse f{\"u}r l{\"a}ngere Zeit w{\"a}hrend der sommerlichen Stratifizierung beeinflussen k{\"o}nnen. Die in dieser Arbeit pr{\"a}sentierten Ergebnisse zeigen Ver{\"a}nderungen bakterieller Gemeinschaften und Prozesse, welche mit dem einhergehenden Klimawandel erwartet werden k{\"o}nnen. Diese sollten bei Beurteilung klimarelevanter Fragen hinsichtlich eines zuk{\"u}nftigen Gew{\"a}sser-managements Ber{\"u}cksichtigung finden.}, language = {en} } @article{HickmannStehle2019, author = {Hickmann, Thomas and Stehle, Fee}, title = {The Embeddedness of Urban Climate Politics in Multilevel Governance}, series = {The journal of environment \& development : a review of international policy}, volume = {28}, journal = {The journal of environment \& development : a review of international policy}, number = {1}, publisher = {Sage Publ.}, address = {Thousand Oaks}, issn = {1070-4965}, doi = {10.1177/1070496518819121}, pages = {54 -- 77}, year = {2019}, abstract = {Numerous scholars have lately highlighted the importance of cities in the global response to climate change. However, we still have little systematic knowledge on the evolution of urban climate politics in the Global South. In particular, we lack empirical studies that examine how local climate actions arise in political-administrative systems of developing and emerging economies. Therefore, this article adopts a multilevel governance perspective to explore the climate mitigation responses of three major cities in South Africa by looking at their vertical and horizontal integration in the wider governance framework. In the absence of a coherent national climate policy, Johannesburg, Cape Town, and Durban have developed distinct climate actions within their jurisdictions. In their effort to address climate change, transnational city networks have provided considerable technical support to these cities. Yet, substantial domestic political-economic obstacles hinder the three cities to develop a more ambitious stance on climate change.}, language = {en} } @phdthesis{Hanschmann2019, author = {Hanschmann, Raffael Tino}, title = {Stalling the engine? EU climate politics after the 'Great Recession'}, doi = {10.25932/publishup-44044}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-440441}, school = {Universit{\"a}t Potsdam}, pages = {XXVIII, 303}, year = {2019}, abstract = {This dissertation investigates the impact of the economic and fiscal crisis starting in 2008 on EU climate policy-making. While the overall number of adopted greenhouse gas emission reduction policies declined in the crisis aftermath, EU lawmakers decided to introduce new or tighten existing regulations in some important policy domains. Existing knowledge about the crisis impact on EU legislative decision-making cannot explain these inconsistencies. In response, this study develops an actor-centred conceptual framework based on rational choice institutionalism that provides a micro-level link to explain how economic crises translate into altered policy-making patterns. The core theoretical argument draws on redistributive conflicts, arguing that tensions between 'beneficiaries' and 'losers' of a regulatory initiative intensify during economic crises and spill over to the policy domain. To test this hypothesis and using social network analysis, this study analyses policy processes in three case studies: The introduction of carbon dioxide emission limits for passenger cars, the expansion of the EU Emissions Trading System to aviation, and the introduction of a regulatory framework for biofuels. The key finding is that an economic shock causes EU policy domains to polarise politically, resulting in intensified conflict and more difficult decision-making. The results also show that this process of political polarisation roots in the industry that is the subject of the regulation, and that intergovernmental bargaining among member states becomes more important, but also more difficult in times of crisis.}, language = {en} } @article{GrimmSeyfarthMihoubHenle2019, author = {Grimm-Seyfarth, Annegret and Mihoub, Jean-Baptiste and Henle, Klaus}, title = {Functional traits determine the different effects of prey, predators, and climatic extremes on desert reptiles}, series = {Ecosphere : the magazine of the International Ecology University}, volume = {10}, journal = {Ecosphere : the magazine of the International Ecology University}, number = {9}, publisher = {Wiley}, address = {Hoboken}, issn = {2150-8925}, doi = {10.1002/ecs2.2865}, pages = {17}, year = {2019}, abstract = {Terrestrial reptiles are particularly vulnerable to climate change. Their highest density and diversity can be found in hot drylands, ecosystems which demonstrate extreme climatic conditions. However, reptiles are not isolated systems but part of a large species assemblage with many trophic dependencies. While direct relations among climatic conditions, invertebrates, vegetation, or reptiles have already been explored, to our knowledge, species' responses to direct and indirect pathways of multiple climatic and biotic factors and their interactions have rarely been examined comprehensively. We investigated direct and indirect effects of climatic and biotic parameters on the individual (body condition) and population level (occupancy) of eight abundant lizard species with different functional traits in an arid Australian lizard community using a 30-yr multi-trophic monitoring study. We used structural equation modeling to disentangle single and interactive effects. We then assessed whether species could be grouped into functional groups according to their functional traits and their responses to different parameters. We found that lizard species differed strongly in how they responded to climatic and biotic factors. However, the factors to which they responded seemed to be determined by their functional traits. While responses on body condition were determined by habitat, activity time, and prey, responses on occupancy were determined by habitat specialization, body size, and longevity. Our findings highlight the importance of indirect pathways through climatic and biotic interactions, which should be included into predictive models to increase accuracy when predicting species' responses to climate change. Since one might never obtain all mechanistic pathways at the species level, we propose an approach of identifying relevant species traits that help grouping species into functional groups at different ecological levels, which could then be used for predictive modeling.}, language = {en} } @article{ChanBoranvanAsseltetal.2019, author = {Chan, Sander and Boran, Idil and van Asselt, Harro and Iacobuta, Gabriela and Niles, Navam and Rietig, Katharine and Scobie, Michelle and Bansard, Jennifer S. and Delgado Pugley, Deborah and Delina, Laurence L. and Eichhorn, Friederike and Ellinger, Paula and Enechi, Okechukwu and Hale, Thomas and Hermwille, Lukas and Hickmann, Thomas and Honegger, Matthias and Hurtado Epstein, Andrea and Theuer, Stephanie La Hoz and Mizo, Robert and Sun, Yixian and Toussaint, Patrick and Wambugu, Geoffrey}, title = {Promises and risks of nonstate action in climate and sustainability governance}, series = {Wiley interdisciplinary reviews : Climate change}, volume = {10}, journal = {Wiley interdisciplinary reviews : Climate change}, number = {3}, publisher = {Wiley}, address = {Hoboken}, issn = {1757-7780}, doi = {10.1002/wcc.572}, pages = {8}, year = {2019}, language = {en} } @misc{AyzelIzhitskiy2019, author = {Ayzel, Georgy and Izhitskiy, Alexander}, title = {Climate change impact assessment on freshwater inflow into the Small Aral Sea}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1071}, issn = {1866-8372}, doi = {10.25932/publishup-47279}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-472794}, pages = {21}, year = {2019}, abstract = {During the last few decades, the rapid separation of the Small Aral Sea from the isolated basin has changed its hydrological and ecological conditions tremendously. In the present study, we developed and validated the hybrid model for the Syr Darya River basin based on a combination of state-of-the-art hydrological and machine learning models. Climate change impact on freshwater inflow into the Small Aral Sea for the projection period 2007-2099 has been quantified based on the developed hybrid model and bias corrected and downscaled meteorological projections simulated by four General Circulation Models (GCM) for each of three Representative Concentration Pathway scenarios (RCP). The developed hybrid model reliably simulates freshwater inflow for the historical period with a Nash-Sutcliffe efficiency of 0.72 and a Kling-Gupta efficiency of 0.77. Results of the climate change impact assessment showed that the freshwater inflow projections produced by different GCMs are misleading by providing contradictory results for the projection period. However, we identified that the relative runoff changes are expected to be more pronounced in the case of more aggressive RCP scenarios. The simulated projections of freshwater inflow provide a basis for further assessment of climate change impacts on hydrological and ecological conditions of the Small Aral Sea in the 21st Century.}, language = {en} } @article{AyzelIzhitskiy2019, author = {Ayzel, Georgy and Izhitskiy, Alexander}, title = {Climate Change Impact Assessment on Freshwater Inflow into the Small Aral Sea}, series = {Water}, volume = {11}, journal = {Water}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2073-4441}, doi = {10.3390/w11112377}, pages = {19}, year = {2019}, abstract = {During the last few decades, the rapid separation of the Small Aral Sea from the isolated basin has changed its hydrological and ecological conditions tremendously. In the present study, we developed and validated the hybrid model for the Syr Darya River basin based on a combination of state-of-the-art hydrological and machine learning models. Climate change impact on freshwater inflow into the Small Aral Sea for the projection period 2007-2099 has been quantified based on the developed hybrid model and bias corrected and downscaled meteorological projections simulated by four General Circulation Models (GCM) for each of three Representative Concentration Pathway scenarios (RCP). The developed hybrid model reliably simulates freshwater inflow for the historical period with a Nash-Sutcliffe efficiency of 0.72 and a Kling-Gupta efficiency of 0.77. Results of the climate change impact assessment showed that the freshwater inflow projections produced by different GCMs are misleading by providing contradictory results for the projection period. However, we identified that the relative runoff changes are expected to be more pronounced in the case of more aggressive RCP scenarios. The simulated projections of freshwater inflow provide a basis for further assessment of climate change impacts on hydrological and ecological conditions of the Small Aral Sea in the 21st Century.}, language = {en} }