Records 1 - 20 / 266
Waterbird habitat requirements and responses to anthropogenic stressors along the Nile in Egypt
Mossad, Haitham ; Hof, A.R. ; Boer, W.F. de; Naguib, M. - \ 2020
In: Wias Annual Conference 2020 WIAS - p. 66 - 66.
In recent decades, human population growth increased rapidly which increased the anthropogenic pressures on natural habitats. Wetland losses due to environmental changes and human pressures are seen as serious threats to waterbird populations. About 23% of global waterbird populations are declining and 19% of waterbird species have been listed as threatened by the IUCN. Human rapid population growth increases the expansion of settlement over natural habitats which can have negative effect on waterbird species.Some waterbird species avoid areas of high human disturbance levels which can results in costing them more energy or end by occupying less food quality areas. Therefore disturbance can affect energy storage of birds and so impact their behaviour, survival, and breeding success. On the other hand, some waterbird species can benefit from human presence, where they can foraging in associated urban areas habitat of rich food supplies.In Egypt, the River Nile basin and the associated linear habitats are surrounded by un hospitable matrix, the Great Sahara. It is important corridor for migration and its mosaic of habitat is considered important as wintering ground and breeding area for many species.The Nile Valley is one of the oldest human-dominated landscapes river basins; where human and wildlife coexist for millennia. In this PhD project, the effect of various environmental variables in different anthropogenic stressor levels on community composition, foraging movements and behaviour, nesting site selection of selected waterbird species will be assessed. The River Nile will be surveyed in Egypt where we will record species and numbers of waterbirds and will determine environmental variables and human disturbance indices in each transect by using field observation combined with GIS software and satellite imageries. Highly disturbed areas are expected to have relatively poor communities, i.e.communities with relatively low species richness and diversity, in comprising of species that tolerate these stressors. Understand the distribution of waterbirds due to environmental variables can help in predicting the influence of anthropogenic stressors on waterbirds wintering along the Nile in Egypt.
Afforestation for climate change mitigation: Potentials, risks and trade-offs
Doelman, Jonathan C. ; Stehfest, Elke ; Vuuren, Detlef P. van; Tabeau, Andrzej ; Hof, Andries F. ; Braakhekke, Maarten C. ; Gernaat, David E.H.J. ; Berg, Maarten van den; Zeist, Willem Jan van; Daioglou, Vassilis ; Meijl, Hans van; Lucas, Paul L. - \ 2020
Global Change Biology 26 (2020)3. - ISSN 1354-1013 - p. 1576 - 1591.
afforestation - climate change mitigation - food security - integrated assessment - land-based mitigation - negative emissions
Afforestation is considered a cost-effective and readily available climate change mitigation option. In recent studies afforestation is presented as a major solution to limit climate change. However, estimates of afforestation potential vary widely. Moreover, the risks in global mitigation policy and the negative trade-offs with food security are often not considered. Here we present a new approach to assess the economic potential of afforestation with the IMAGE 3.0 integrated assessment model framework. In addition, we discuss the role of afforestation in mitigation pathways and the effects of afforestation on the food system under increasingly ambitious climate targets. We show that afforestation has a mitigation potential of 4.9 GtCO2/year at 200 US$/tCO2 in 2050 leading to large-scale application in an SSP2 scenario aiming for 2°C (410 GtCO2 cumulative up to 2100). Afforestation reduces the overall costs of mitigation policy. However, it may lead to lower mitigation ambition and lock-in situations in other sectors. Moreover, it bears risks to implementation and permanence as the negative emissions are increasingly located in regions with high investment risks and weak governance, for example in Sub-Saharan Africa. Afforestation also requires large amounts of land (up to 1,100 Mha) leading to large reductions in agricultural land. The increased competition for land could lead to higher food prices and an increased population at risk of hunger. Our results confirm that afforestation has substantial potential for mitigation. At the same time, we highlight that major risks and trade-offs are involved. Pathways aiming to limit climate change to 2°C or even 1.5°C need to minimize these risks and trade-offs in order to achieve mitigation sustainably.
Landskapsplanering av skog : för biologisk mångfald och ettvarierat skogsbruk
Michanek, Gabriel ; Bonstedt, Göran ; Jong, Johnny de; Ekvall, Hans ; Forsberg, Maria ; Hof, Anouschka ; Sjögren, Jörgen ; Zabel von Felten, Astrid - \ 2019
Stockholm : Naturvårdsverket (Rapport / Naturvårdsverket 6909) - ISBN 9789162069094 - 96
Investigating the role of the eurasian badger (Meles meles) in the nationwide distribution of the western european hedgehog (Erinaceus europaeus) in England
Hof, Anouschka R. ; Allen, Andrew M. ; Bright, Paul W. - \ 2019
Animals 9 (2019)10. - ISSN 2076-2615
Citizen science - Conservation - Displacement - Predator-prey interaction - Spatial use
Biodiversity is declining globally, which calls for effective conservation measures. It is, therefore, important to investigate the drivers behind species presence at large spatial scales. The Western European hedgehog (Erinaceus europaeus) is one of the species facing declines in parts of its range. Yet, drivers of Western European hedgehog distribution at large spatial scales remain largely unknown. At local scales, the Eurasian badger (Meles meles), an intraguild predator of the Western European hedgehog, can affect both the abundance and the distribution of the latter. However, the Western European hedgehog and the Eurasian badger have shown to be able to co-exist at a landscape scale. We investigated whether the Eurasian badger may play a role in the likelihood of the presence of the Western European hedgehog throughout England by using two nationwide citizen science surveys. Although habitat-related factors explained more variation in the likelihood of Western European hedgehog presence, our results suggest that Eurasian badger presence negatively impacts the likelihood of Western European hedgehog presence. Intraguild predation may, therefore, be influencing the nationwide distribution of hedgehogs in England, and further research is needed about how changes in badger densities and intensifying agricultural practices that remove shelters like hedgerows may influence hedgehog presence.
Paying the price for the meat we eat
Allen, Andrew M. ; Hof, Anouschka R. - \ 2019
Environmental Science & Policy 97 (2019). - ISSN 1462-9011 - p. 90 - 94.
Biodiversity offsetting - Climate change - Ecological compensation - Intensive agriculture - Meat consumption
An increasingly gloomy picture is painted by research focusing on the environmental challenges faced by our planet. Biodiversity loss is ongoing, landscapes continue to transform, and predictions on the effects of climate change worsen. Calls have been made for urgent action to avoid pushing our planet into a new system state. One of the principal threats to biodiversity is intensive agriculture, and in particular the livestock industry, which is an important driver of greenhouse gas emissions, habitat degradation and habitat loss. Ongoing intensification of agricultural practices mean that farmland no longer provides a habitat for many species. We suggest the use of a growing policy tool, biodiversity offsetting, to tackle these challenges. Biodiversity offsetting, or ecological compensation, assesses the impacts of new development projects and seeks to avoid, minimise and otherwise compensate for the ecological impacts of these development projects. By applying biodiversity offsetting to agriculture, the impacts of progressively intensifying farming practices can be compensated to achieve conservation outcomes by using tools like environmental taxes or agri-environment schemes. Low intensity, traditional, farming systems provide a number of benefits to biodiversity and society, and we suggest that the consumer and the agriculture industry compensate for the devastating ecological impacts of intensive farming so that we can once again preserve biodiversity in our landscapes and attempt to limit global temperature rise below 2°c.
Dynamics of the Gut Microbiota in Children Receiving Selective or Total Gut Decontamination Treatment during Hematopoietic Stem Cell Transplantation
Bekker, Vincent ; Zwittink, Romy D. ; Knetsch, Cornelis W. ; Sanders, Ingrid M.J.G. ; Berghuis, Dagmar ; Heidt, Peter J. ; Vossen, Jaak M.J.J. ; Vos, Willem M. de; Belzer, Clara ; Bredius, Robbert G.M. ; van‘t Hof, Peter J. ; Lankester, Arjan C. ; Kuijper, Ed J. - \ 2019
Biology of Blood and Marrow Transplantation 25 (2019)6. - ISSN 1083-8791 - p. 1164 - 1171.
Graft-versus-host disease - Gut decontamination - Hematopoietic stem cell transplantation - Microbiota - Pediatrics
Bloodstream infections and graft-versus-host disease are common complications after hematopoietic stem cell transplantation (HSCT) procedures, associated with the gut microbiota that acts as a reservoir for opportunistic pathogens. Selective gut decontamination (SGD) and total gut decontamination (TGD) during HSCT have been associated with a decreased risk of developing these complications after transplantation. However, because studies have shown conflicting results, the use of these treatments remains subject of debate. In addition, their impact on the gut microbiota is not well studied. The aim of this study was to elucidate the dynamics of the microbiota during and after TGD and to compare these with the dynamics of SGD. In this prospective, observational, single-center study fecal samples were longitudinally collected from 19 children eligible for allogenic HSCT (TGD, n=12; SGD, n=7), weekly during hospital admission and monthly after discharge. In addition, fecal samples were collected from 3 family stem cell donors. Fecal microbiota structure of patients and donors was determined by 16S rRNA gene amplicon sequencing. Microbiota richness and diversity markedly decreased during SGD and TGD and gradually increased after cessation of decontamination treatment. During SGD, gut microbiota composition was relatively stable and dominated by Bacteroides, whereas it showed high inter- and intraindividual variation and low Bacteroides abundance during TGD. In some children TGD allowed the genera Enterococcus and Streptococcus to thrive during treatment. A gut microbiota dominated by Bacteroides was associated with increased predicted activity of several metabolic processes. Comparing the microbiota of recipients and their donors indicated that receiving an SCT did not alter the patient's microbiota to become more similar to that of its donor. Overall, our findings indicate that SGD and TGD affect gut microbiota structure in a treatment-specific manner. Whether these treatments affect clinical outcomes via interference with the gut microbiota needs to be further elucidated.
Implications of various effort-sharing approaches for national carbon budgets and emission pathways
Berg, Nicole J. van den; Soest, Heleen L. van; Hof, Andries F. ; Elzen, Michel G.J. den; Vuuren, Detlef P. van; Chen, Wenying ; Drouet, Laurent ; Emmerling, Johannes ; Fujimori, Shinichiro ; Höhne, Niklas ; Kõberle, Alexandre C. ; McCollum, David ; Schaeffer, Roberto ; Shekhar, Swapnil ; Vishwanathan, Saritha Sudharmma ; Vrontisi, Zoi ; Blok, Kornelis - \ 2019
Climatic Change (2019). - ISSN 0165-0009
The bottom-up approach of the Nationally Determined Contributions (NDCs) in the Paris Agreement has led countries to self-determine their greenhouse gas (GHG) emission reduction targets. The planned ‘ratcheting-up’ process, which aims to ensure that the NDCs comply with the overall goal of limiting global average temperature increase to well below 2 °C or even 1.5 °C, will most likely include some evaluation of ‘fairness’ of these reduction targets. In the literature, fairness has been discussed around equity principles, for which many different effort-sharing approaches have been proposed. In this research, we analysed how country-level emission targets and carbon budgets can be derived based on such criteria. We apply novel methods directly based on the global carbon budget, and, for comparison, more commonly used methods using GHG mitigation pathways. For both, we studied the following approaches: equal cumulative per capita emissions, contraction and convergence, grandfathering, greenhouse development rights and ability to pay. As the results critically depend on parameter settings, we used the wide authorship from a range of countries included in this paper to determine default settings and sensitivity analyses. Results show that effort-sharing approaches that (i) calculate required reduction targets in carbon budgets (relative to baseline budgets) and/or (ii) take into account historical emissions when determining carbon budgets can lead to (large) negative remaining carbon budgets for developed countries. This is the case for the equal cumulative per capita approach and especially the greenhouse development rights approach. Furthermore, for developed countries, all effort-sharing approaches except grandfathering lead to more stringent budgets than cost-optimal budgets, indicating that cost-optimal approaches do not lead to outcomes that can be regarded as fair according to most effort-sharing approaches.
An uncertain future for the endemic Galliformes of the Caucasus
Hof, Anouschka R. ; Allen, Andrew M. - \ 2019
Science of the Total Environment 651 (2019). - ISSN 0048-9697 - p. 725 - 735.
Birds - Climate change - Conservation - Land use - Species distribution modelling
Impacts of climate change are already evident in ecosystems worldwide. High-latitude and altitude regions are at greatest risk because the effects of climate change are greater in these regions, and species from these areas have limited ability to track their climate envelopes. The Caucasian snowcock (Tetraogallus caucasicus) and the Caucasian grouse (Lyrurus mlokosiewiczi) are both high-altitude specialists that are endemic to a restricted range in the Caucasus mountains of Europe. Little research has been performed to determine the status of the populations or the potential impacts of climate change. We investigated how climate and land use change may impact both species in future and determined whether their life history traits may increase their vulnerability using a combined exposure and trait-based index. We compared several climate models, and in all instances, both species showed drastic range contractions although the extent of the contraction varied with each model. Traits like habitat specialism, ground nesting and incubation period meant that both species may be considered “most vulnerable” in the exposure and trait-based index. Given that both species already occur near the maximum elevations of the Caucasus, and that they lack any dispersal capabilities due to the isolation from alternative mountainous areas, research efforts need to be prioritized to improve our knowledge about their population status, to monitor future trends and to begin developing species action plans that conserve these endemic and iconic species of Europe. Both species are flagship and umbrella species and may serve as indicator species, their protection may therefore benefit a whole range of other species inhabiting this vulnerable Alpine ecosystem. Especially the Caucasian grouse has a high aesthetic value and is favoured by hunters in the region. The potential demise of this species may therefore also be negative for local communities.
Gut microbiota structure in the course of pediatric allo-HSCT
Bekker, Vincent ; Zwittink, Romy ; Knetsch, Cornelis W. ; Sanders, Ingrid M.J.G. ; Berghuis, Dagmar ; Heidt, Peter J. ; Vossen, Jaak M.J.J. ; Vos, Willem de; Belzer, Clara ; Bredius, Robbert G.M. ; van‘t Hof, Peter J. ; Lankester, Arjan C. ; Kuijper, Ed J. - \ 2018
Leiden University Medical Centre
PRJEB28845 - ERP111102 - Homo sapiens
Effect of selective and total gut decontamination treatments on gut microbiota structure in the course of pediatric allogenic HSCT, as determined via 16S rRNA gene amplicon sequencing.
|Een kleine geschiedenis van tarweteelt in Nederland
Bas, Noortje - \ 2018
Bijeenkomst van boeren, molenaars, bakkers op Het Geweide Hof, Garmerwolde, 2 juli.
Simulating long-term effects of bioenergy extraction on dead wood availability at a landscape scale in Sweden
Hof, Anouschka R. ; Löfroth, Therese ; Rudolphi, Jörgen ; Work, Timothy ; Hjältén, Joakim - \ 2018
Forests 9 (2018)8. - ISSN 1999-4907
Biodiversity - Biofuel - Boreal forest - Modelling - Saproxylic species
Wood bioenergy may decrease the reliance on fossil carbon and mitigate anticipated increases in temperature. However, increased use of wood bioenergy may have large impacts on forest biodiversity primarily through the loss of dead wood habitats. We evaluated both the large-scale and long-term effects of different bioenergy extraction scenarios on the availability of dead wood and the suitability of the resulting habitat for saproxylic species, using a spatially explicit forest landscape simulation framework applied in the Swedish boreal forest. We demonstrate that bioenergy extraction scenarios, differing in the level of removal of biomass, can have significant effects on dead wood volumes. Although all of the scenarios led to decreasing levels of dead wood, the scenario aimed at species conservation led to highest volumes of dead wood (about 10 m3 ha-1) and highest connectivity of dead wood patches (mean proximity index of 78), whilst the scenario aimed at reaching zero fossil fuel targets led to the lowest levels (about 8 m3 ha-1) and least connectivity (mean proximity index of 7). Our simulations stress that further exploitation of dead wood from sites where volumes are already below suggested habitat thresholds for saproxylic species will very likely have further negative effects on dead wood dependent species.
The ecology of Black Guillemot Cepphus grylle grylle chicks in the Baltic Sea region : insights into their diet, survival, nest predation and moment of fledging
Hof, Anouschka R. ; Crombag, Joep A.H.M. ; Allen, Andrew M. - \ 2018
Bird Study 65 (2018)3. - ISSN 0006-3657 - p. 357 - 364.
Capsule: The diet of Black Guillemot Cepphus grylle grylle chicks in the Baltic Sea region was dominated by Viviparous Eelpout Zoarces viviparus. Risk of nest predation by avian and mammalian predators was perceived to be low, and hatching and fledging success were high. Aims: To gain insight into the ecology of nestling Black Guillemots in the Baltic Sea region to fill knowledge gaps and benefit its conservation. Methods: Two island groups in the Baltic Sea were visited several times during the breeding season of 2014 and 2015 to monitor nestling survival and fledging. In addition, camera traps were used in 2014 to monitor prey brought to chicks by adults and record possible nest predation events. Results: Hatching success was 0.89 and 0.73 in 2014 and 2015, respectively, and fledging success was very high (0.95 and 0.97). No incidences of avian or mammalian predation were observed. Chicks fledged at night between 32 and 38 days after hatching. Viviparous Eelpout made up 95% of the prey items brought to the chicks by adults. Conclusions: The hatching rate and fledging rate of the Black Guillemot was high in our study region. Juveniles seemed highly dependent on the availability of eelpout. Changes in the abundance of this species may therefore have negative effects on chick survival.
Europees Hof remt kwekers vanwege genetische modificatie
Smulders, Rene - \ 2018
Landscape planning-paving theway for effective conservation of forest biodiversity and a diverse forestry?
Michanek, Gabriel ; Bostedt, Göran ; Ekvall, Hans ; Forsberg, Maria ; Hof, Anouschka R. ; Jong, Johnny de; Rudolphi, Jörgen ; Zabel, Astrid - \ 2018
Forests 9 (2018)9. - ISSN 1999-4907
Aichi targets - Biodiversity - Birds directive - Boreal forest - Compensation - Fragmentation - Habitat protection - Habitats directive - Landscape planning - Tax-fund
Globally, intensive forestry has led to habitat degradation and fragmentation of the forest landscape. Taking Sweden as an example, this development is contradictory to international commitments, EU obligations, and to the fulfillment of the Parliament's environmental quality objective "Living Forests", which according to Naturvårdsverket (The Swedish Environmental Protection Agency) will not be achieved in 2020 as stipulated. One important reason for the implementation deficit is the fragmented forestry management. In a forest landscape, felling and other measures are conducted at different times on separate forest stands (often relatively small units) by different operators. Consequently, the authorities take case by case decisions on felling restrictions for conservation purposes. In contrast, conservation biology research indicates a need for a broad geographical and strategical approach in order to, in good time, select the most appropriate habitats for conservation and to provide for a functioning connectivity between different habitats. In line with the EU Commission, we argue that landscape forestry planning could be a useful instrument to achieve ecological functionality in a large area. Landscape planning may also contribute to the fulfilment of Sweden's climate and energy policy, by indicating forest areas with insignificant conservation values, where intensive forestry may be performed for biomass production etc. Forest owners should be involved in the planning and would, under certain circumstances, be entitled to compensation. As state resources for providing compensation are scarce, an alternative could be to introduce a tax-fund system within the forestry sector. Such a system may open for voluntary agreements between forest owners for the protection of habitats within a large area.
DNA methylation as a mediator of the association between prenatal adversity and risk factors for metabolic disease in adulthood
Tobi, Elmar W. ; Slieker, Roderick C. ; Luijk, René ; Dekkers, Koen F. ; Stein, Aryeh D. ; Xu, Kate M. ; Slagboom, P.E. ; Zwet, Erik W. Van; Lumey, L.H. ; Heijmans, Bastiaan T. ; T'Hoen, Peter A. ; Pool, René ; Greevenbroek, Marleen M. Van; Stehouwer, Coen D. ; Kallen, Carla J. Van Der; Schalkwijk, Casper G. ; Wijmenga, Cisca ; Zhernakova, Sasha ; Tigchelaar, Ettje F. ; Beekman, Marian ; Deelen, Joris ; Heemst, Diana Van; Veldink, Jan H. ; Berg, Leonard H. Van Den; Duijn, Cornelia M. Van; Hofman, Albert ; Uitterlinden, André G. ; Jhamai, P.M. ; Verbiest, Michael ; Verkerk, Marijn ; Breggen, Ruud Van Der; Rooij, Jeroen Van; Lakenberg, Nico ; Mei, Hailiang ; Bot, Jan ; Zhernakova, Dasha V. ; Hof, Peter Van 't; Deelen, Patrick ; Nooren, Irene ; Moed, Matthijs ; Vermaat, Martijn ; Jan Bonder, Marc ; Dijk, Freerk Van; Arindrarto, Wibowo ; Kielbasa, Szymon M. ; Swertz, Morris A. ; Isaacs, Aaron ; Franke, Lude - \ 2018
Science Advances 4 (2018)1. - ISSN 2375-2548
Although it is assumed that epigenetic mechanisms, such as changes in DNA methylation (DNAm), underlie the relationship between adverse intrauterine conditions and adult metabolic health, evidence from human studies remains scarce. Therefore, we evaluated whether DNAm in whole blood mediated the association between prenatal famine exposure and metabolic health in 422 individuals exposed to famine in utero and 463 (sibling) controls. We implemented a two-step analysis, namely, a genome-wide exploration across 342, 596 cytosine-phosphate-guanine dinucleotides (CpGs) for potential mediators of the association between prenatal famine exposure and adult body mass index (BMI), serum triglycerides (TG), or glucose concentrations, which was followed by formalmediation analysis.DNAm mediated the association of prenatal famine exposure with adult BMI and TG but not with glucose. DNAm at PIM3 (cg09349128), a gene involved in energy metabolism, mediated 13.4% [95% confidence interval (CI), 5 to 28%] of the association between famine exposure and BMI. DNAm at six CpGs, including TXNIP (cg19693031), influencing b cell function, and ABCG1 (cg07397296), affecting lipid metabolism, together mediated 80% (95% CI, 38.5 to 100%) of the association between famine exposure and TG. Analyses restricted to those exposed to famine during early gestation identified additional CpGs mediating the relationship with TG near PFKFB3 (glycolysis) and METTL8 (adipogenesis). DNAm at the CpGs involved was associated with gene expression in an external data set and correlated with DNAm levels in fat depots in additional postmortem data. Our data are consistent with the hypothesis that epigenetic mechanisms mediate the influence of transient adverse environmental factors in early life on long-termmetabolic health. The specific mechanism awaits elucidation.
Are we restoring enough? : Simulating impacts of restoration efforts on the suitability of forest landscapes for a locally critically endangered umbrella species
Hof, A.R. ; Hjältén, J. - \ 2018
Restoration Ecology 26 (2018)4. - ISSN 1061-2971 - p. 740 - 750.
Habitat restoration is often implemented to mitigate the negative effects of intensive forestry on biodiversity. It may be increasingly adopted in future to alleviate additional negative effects of climate change. Ascertaining the restoration effort needed to fulfill project goals is difficult. Insights may be gained through simulating the effects of restoration efforts on landscape dynamics through time. Here we used a spatially explicit landscape simulation model to simulate the effects of different restoration efforts on forest landscapes in Sweden to assess the level of mitigation that is needed to allow viable populations of the locally critically endangered White-backed Woodpecker (Dendrocopos leucotos); an umbrella species whose protection may serve the protection of a range of other species. Based on the goals of the protection plan for the species, which reflect its habitat requirements, we evaluated which of several restoration scenarios could fulfill goals with respect to (1) the amount of deciduous forest; (2) the amount of dead wood; and (3) the age of the forest. We found that whereas it may be relatively easy and quick to acquire high levels of dead wood, increasing the proportions of deciduous forest and of old forests require considerably more time and effort. Also, current management actions would not be sufficient to create the required amount of habitat to conserve the White-backed Woodpecker in our study region. Simulations like ours can provide valuable information about the levels of restoration needed through time to fulfill project goals and may prevent wasting valuable resources, time, effort, and money.
Assessing the ambition of post-2020 climate targets : a comprehensive framework
Höhne, Niklas ; Fekete, Hanna ; Elzen, Michel G.J. den; Hof, Andries F. ; Kuramochi, Takeshi - \ 2018
Climate Policy 18 (2018)4. - ISSN 1469-3062 - p. 425 - 441.
ambition - global stocktake - INDCs - NDCs - Paris agreement - UNFCCC
One of the most fundamental questions surrounding the new Paris Agreement is whether countries’ proposals to reduce GHG emissions after 2020 are equally ambitious, considering differences in circumstances between countries. We review a variety of approaches to assess the ambition of the GHG emission reduction proposals by countries. The approaches are applied illustratively to the mitigation part of the post-2020 climate proposals (nationally determined contributions, or NDCs) by China, the EU, and the US. The analysis reveals several clear trends, even though the results differ per individual assessment approach. We recommend that such a comprehensive ambition assessment framework, employing a large variety of approaches, is used in the future to capture a wide spectrum of perspectives on ambition. POLICY RELEVANCE Assessing the ambition of the national climate proposals is particularly important as the Paris Agreement asks for regular reviews of national contributions, keeping in mind that countries raise their ambition over time. Such an assessment will be an important part of the regular global stocktake that will take place every five years, starting with a ‘light’ version in 2018. However, comprehensive methods to assess the proposals are lacking. This article provides such a comprehensive assessment framework.
Contribution of trans regulatory eQTL to cryptic genetic variation in C. elegans
Snoek, L.B. ; Sterken, M.G. ; Bevers, R.P.J. ; Volkers, J.M. ; Hof, Arjen van 't; Brenchley, Rachel ; Riksen, J.A.G. ; Cossins, Andrew ; Kammenga, J.E. - \ 2017
Wageningen University & Research
Caenorhabditis elegans - genetical genomics - eQTL - heat stress - cryptic genetic variation - trans-band - eQTL hotspot
Background Cryptic genetic variation (CGV) is the hidden genetic variation that can be unlocked by perturbing normal conditions. CGV can drive the emergence of novel complex phenotypes through changes in gene expression. Although our theoretical understanding of CGV has thoroughly increased over the past decade, insight into polymorphic gene expression regulation underlying CGV is scarce. Here we investigated the transcriptional architecture of CGV in response to rapid temperature changes in the nematode Caenorhabditis elegans. We analyzed regulatory variation in gene expression (and mapped eQTL) across the course of a heat stress and recovery response in a recombinant inbred population. Results We measured gene expression over three temperature treatments: i) control, ii) heat stress, and iii) recovery from heat stress. Compared to control, exposure to heat stress affected the transcription of 3305 genes, whereas 942 were affected in recovering animals. These affected genes were mainly involved in metabolism and reproduction. The gene expression pattern in recovering animals resembled both the control and the heat-stress treatment. We mapped eQTL using the genetic variation of the recombinant inbred population and detected 2626 genes with an eQTL in the heat-stress treatment, 1797 in the control, and 1880 in the recovery. The cis-eQTL were highly shared across treatments. A considerable fraction of the trans-eQTL (40â€“57%) mapped to 19 treatment specific trans-bands. In contrast to cis-eQTL, trans-eQTL were highly environment specific and thus cryptic. Approximately 67% of the trans-eQTL were only induced in a single treatment, with heat-stress showing the most unique trans-eQTL. Conclusions These results illustrate the highly dynamic pattern of CGV across three different environmental conditions that can be evoked by a stress response over a relatively short time-span (2Â h) and that CGV is mainly determined by response related trans regulatory eQTL.
Data from: How bird clades diversify in response to climatic and geographic factors
Rodríguez-Castañeda, Genoveva ; Hof, A.R. ; Jansson, Roland - \ 2017
climate stability - ecological niche modelling - energy availability - geographic area - habitat diversity - phylogenetic independent contrasts - sister group comparisons - species richness - temperate - tropical - Aves
While the environmental correlates of global patterns in standing species richness are well understood, it is poorly known which environmental factors promote diversification (speciation minus extinction) in clades. We tested several hypotheses for how geographic and climatic variables should affect diversification using a large dataset of bird sister genera endemic to the New World. We found support for the area, evolutionary speed, environmental predictability and climatic stability hypotheses, but productivity and topographic complexity were rejected as explanations. Genera that had accumulated more species tend to occupy wider niche space, manifested both as occurrence over wider areas and in more habitats. Genera with geographic ranges that have remained more stable in response to glacial-interglacial changes in climate were also more species rich. Since many relevant explanatory variables vary latitudinally, it is crucial to control for latitude when testing alternative mechanistic explanations for geographic variation in diversification among clades.
Assessing the impacts of 1.5°C global warming - Simulation protocol of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP2b)
Frieler, Katja ; Lange, Stefan ; Piontek, Franziska ; Reyer, Christopher P.O. ; Schewe, Jacob ; Warszawski, Lila ; Zhao, Fang ; Chini, Louise ; Denvil, Sebastien ; Emanuel, Kerry ; Geiger, Tobias ; Halladay, Kate ; Hurtt, George ; Mengel, Matthias ; Murakami, Daisgbre ; Ostberg, Sebastian ; Popp, Alexander ; Riva, Riccardo ; Stevanovic, Miodrag ; SuzGBRi, Tatsuo ; Volkholz, Jan ; Burke, Eleanor ; Ciais, Philippe ; Ebi, Kristie ; Eddy, Tyler D. ; Elliott, Joshua ; Galbraith, Eric ; Gosling, Simon N. ; Hattermann, Fred ; Hickler, Thomas ; Hinkel, Jochen ; Hof, Christian ; Huber, Veronika ; Jägermeyr, Jonas ; Krysanova, Valentina ; Marcé, Rafael ; Müller Schmied, Hannes ; Mouratiadou, Ioanna ; Pierson, Don ; Tittensor, Derek P. ; Vautard, Robert ; Vliet, Michelle Van; Biber, Matthias F. ; Betts, Richard A. ; Leon Bodirsky, Benjamin ; Deryng, Delphine ; Frolking, Steve ; Jones, Chris D. ; Lotze, Heike K. ; Lotze-Campen, Hermann ; Sahajpal, Ritvik ; Thonicke, Kirsten ; Tian, Hanqin ; Yamagata, Yoshiki - \ 2017
Geoscientific Model Development 10 (2017)12. - ISSN 1991-959X - p. 4321 - 4345.
In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a
special report in 2018 on the impacts of global warming of 1.5ĝ€°C above pre-industrial levels and related global greenhouse gas emission pathways. In Nairobi, Kenya, April 2016, the IPCC panel accepted the invitation. Here we describe the response devised within the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) to provide tailored, cross-sectorally consistent impact projections to broaden the scientific basis for the report. The simulation protocol is designed to allow for (1) separation of the impacts of historical warming starting from pre-industrial conditions from impacts of other drivers such as historical land-use changes (based on pre-industrial and historical impact model simulations); (2) quantification of the impacts of additional warming up to 1.5ĝ€°C, including a potential overshoot and long-term impacts up to 2299, and comparison to higher levels of global mean temperature change (based on the low-emissions Representative Concentration Pathway RCP2.6 and a no-mitigation pathway RCP6.0) with socio-economic conditions fixed at 2005 levels; and (3) assessment of the climate effects based on the same climate scenarios while accounting for simultaneous changes in socio-economic conditions following the middle-of-the-road Shared Socioeconomic Pathway (SSP2, Fricko et al., 2016) and in particular differential bioenergy requirements associated with the transformation of the energy system to comply with RCP2.6 compared to RCP6.0. With the aim of providing the scientific basis for an aggregation of impacts across sectors and analysis of cross-sectoral interactions that may dampen or amplify sectoral impacts, the protocol is designed to facilitate consistent impact projections from a range of impact models across different sectors (global and regional hydrology, lakes, global crops, global vegetation, regional forests, global and regional marine ecosystems and fisheries, global and regional coastal infrastructure, energy supply and demand, temperature-related mortality, and global terrestrial biodiversity).