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The strong linkages between disaster risk reduction and the environment are well-acknowledged, and are magnified by the impacts of climate change on the severity and frequency of environmental disasters (landslides, floods, storm surges, forest fires, etc). Most of the time, ecosystems themselves can offer sustainable solutions for the reduction of disaster risks and the severity of their impacts, while adapting to global changes. Nature-Based Solutions, Ecosystem-based Adaptation, Green Infrastructure and Natural Water Retention Measures are examples of ecosystem-based initiatives that have been promoted by the European Commission to address a variety of policy goals. In this context, ecosystem-based approaches for Disaster Risk Reduction aim at improving the condition and resilience of ecosystems in urban, rural and wilderness areas and as such, contribute to implementing the new Sendai Framework for Disaster Risk Reduction 2015–2030, while also contributing to achieving other policy objectives - from biodiversity conservation to climate change adaptation. The European Commission has also been actively engaging the research community to better address disaster risk management knowledge and technology gaps through its Research and Innovation strategy and Framework Programmes, notably Horizon 2020. Research has shown that ecosystem-based approaches are often cost-effective and provide a wide range of co-benefits for local and regional economies, social cohesion and the broader environment. Fostering green growth through promoting risk-proofed investments and building the capacity of local, regional and national authorities and communities is a priority of the EU Action Plan for Disaster Risk Reduction, which sets the basis for a disaster-risk-informed approach to policy making at EU level.

International audience; As phytohormones lie at the very core of molecular mechanisms controlling the plant physiology and development, they have long been hypothesized to be involved in insect-induced plant manipulations. Cytokinins (CKs) are phytohormones now widely recognized to be utilized by leaf-mining and gall-inducing insects in the control of the physiology of their host plant. In some leaf-mining moth species, larvae can supply the hormones themselves, bacterial symbionts contributing to the production of CKs. Our objective was to investigate whether closely related leaf-miner species sharing the same ecological niche but differing in their Wolbachia infection status develop similar strategies to manipulate their host plant. An extensive identification and quantification of CKs has been used to elucidate physiological patterns relevant for the plant-insect interactions. Our results show that modulation of plant CK levels is impaired in the Wolbachia-free leaf-mining moth Phyllonoryc-ter mespilella (H€ ubner) (Lepidoptera: Gracillariidae) contrasting with results previously observed in the closely related moth species Phyllonorycter blancardella (Fabricius) that produce and deliver CKs to the plant through an intricate interaction with Wolbachia. Our study suggests that mechanisms underlying colonization of the host plant and adaptation to fluctuating environmental conditions are different between the two leaf-miner species and that P. mespilella larvae most likely do not produce CKs. This species rather only buffers the degradation of CKs naturally occurring during the senescence of leaves leading to few active CKs being maintained at a sufficiently high level to induce and maintain a 'green island' phenotype (photosynthetically active green patches in otherwise senescing leaves). This study further provides converging experimental evidence pointing toward the influence of bacterial symbionts in the ability of leaf-mining moths to control the physiology of their host plant with consequences for their ecology and evolutionary diversification.

Contemporary societies are facing a broad range of challenges, from pressures on human health and well-being to natural capital depletion, and the security of food, water and energy. These challenges are deeply intertwined with global processes, such as climate change and with local events such as natural disasters. The EU's research & innovation (R&I) policy is now seeking to address these challenges from a new perspective, with Nature-Based Solutions, and turn them into innovation opportunities that optimise the synergies between nature, society and the economy. Nature-Based Solutions can be an opportunity for innovation, and are here promoted by both policymakers and practitioners as a cost-effective way of creating a greener, more sustainable, and more competitive economy. Since 2013, the European Commission has devoted particular attention to Nature-Based Solutions through consultations and dialogues that sought to make the concept of these solutions more concrete and to define the concept's place within the spectrum of ecosystem-based approaches. In 2014, the Commission launched an expert group, which conducted further analysis, and made recommendations to help increase the use of Nature-Based Solutions and bring nature back into cities. In 2015, a survey was conducted on citizens' views and perceptions of 'Nature in Cities' to provide further insight for future work. Based on these elements and on results from running EU projects, the Commission has developed an R&I agenda for Nature-Based Solutions and has published targeted calls for proposals for large-scale demonstration projects in this field in 2016 and 2017. Additional R&I actions at EU level that promote systemic Nature-Based Solutions and their benefits to cities and territories are planned with the aim to improve the implementation capacity and evidence base for deploying Nature-Based Solutions and developing corresponding future markets. They are also expected to foster an interdisciplinary R&I and stakeholder community and the exchange of good practices in this field, as well as help shaping and implementing international R&I agendas on Nature-Based Solutions.

International audience; The fixation probability of a recessive beneficial mutation is increased on the X or Z chromosome, relative to autosomes, because recessive alleles carried by X or Z are exposed to selection in the heterogametic sex. This leads to an increased dN/dS ratio on sex chromosomes relative to autosomes, a pattern called the "fast-X" or "fast-Z" effect. Besides positive selection, the strength of genetic drift and the efficacy of purifying selection, which affect the rate of molecular evolution, might differ between sex chromosomes and autosomes. Disentangling the complex effects of these distinct forces requires the genome-wide analysis of polymor-phism, divergence and gene expression data in a variety of taxa. Here we study the influence of hemizygosity of the Z chromosome in Maniola jurtina and Pyronia tithonus, two species of butterflies (Lepidoptera, Nymphalidae, Satyrinae). Using transcriptome data, we compare the strength of positive and negative selection between Z and autosomes accounting for sex-specific gene expression. We show that M. jurtina and P. tithonus do not experience a faster, but rather a slightly slower evolutionary rate on the Z than on autosomes. Our analysis failed to detect a significant difference in adaptive evolutionary rate between Z and autosomes, but comparison of male-biased, unbiased and female-biased Z-linked genes revealed an increased efficacy of purifying selection against recessive deleterious mutations in female-biased Z-linked genes. This probably contributes to the lack of fast-Z evolution of satyrines. We suggest that the effect of hemizygosity on the fate of recessive deleterious mutations should be taken into account when interpreting patterns of molecular evolution in sex chromosomes vs. autosomes.

Ecosystem-based management advocates that forestry disturbances should aim to emulate natural disturbances to mitigate the landscape-level impact of forest management. This study compares the impact of clear-cuts followed by a prescribed burn (CCPB) with clear-cuts alone (CC) and current careful logging practices (CLAAG: “careful logging around advanced growth”) on understory composition within black spruce (Picea mariana Miller (BSP)) paludified forest stands at the plot, site, and treatment levels using a functional-type approach. Vascular and nonvascular taxa showed significant differences in composition at the plot level among treatments. We found that pioneer taxa occurred mainly in CCPB sites, while late-successional taxa characterized CC sites. CLAAG sites had higher taxa richness than CCPB and CC sites, and we found that CCPB treatments were most likely to promote vascular taxa compositions that are more similar to those observed after natural disturbances. Additionally, the relative abundance of Sphagnum spp., responsible for paludification, was significantly reduced in sites treated by prescribed burning. This study therefore presents results suggesting that prescribed burning might represent a sustainable alternative to current harvesting techniques in the Clay Belt of eastern Canada that could help in preserving biodiversity (in terms of understory species assemblage) while maintaining or even enhancing forest productivity.

Genome-scale diversity data are increasingly available in a variety of biological systems, and can be used to reconstruct the past evolutionary history of species divergence. However, extracting the full demographic information from these data is not trivial, and requires inferential methods that account for the diversity of coalescent histories throughout the genome. Here, we evaluate the potential and limitations of one such approach. We reexamine a well-known system of mussel sister species, using the joint site frequency spectrum (jSFS) of synonymous mutations computed either from exome capture or RNA-seq, in an Approximate Bayesian Computation (ABC) framework. We first assess the best sampling strategy (number of: individuals, loci, and bins in the jSFS), and show that model selection is robust to variation in the number of individuals and loci. In contrast, different binning choices when summarizing the joint site frequency spectrum, strongly affect the results: including classes of low and high frequency shared polymorphisms can more effectively reveal recent migration events. We then take advantage of the flexibility of ABC to compare more realistic models of speciation, including variation in migration rates through time (i.e. periodic connectivity) and across genes (i.e. genome-wide heterogeneity in migration rates). We show that these models were consistently selected as the most probable, suggesting that mussels have experienced a complex history of gene flow during divergence and that the species boundary is semi-permeable. Our work provides a comprehensive evaluation of ABC demographic inference in mussels based on the coding site frequency spectrum, and supplies guidelines for employing different sequencing techniques and sampling strategies. We emphasize, perhaps surprisingly, that inferences are less limited by the volume of data, than by the way in which they are analyzed.

AGAP : GE2pop - Génomique évolutive et gestion des populations; International audience; Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out in natural field conditions. We examined the evolutionary response to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies associated to changes in soil temperature and soil moisture. This shows an evolutionary response to realistic climate change happening over short-time scale, and calls for incorporating evolution into models predicting future response of species to climate change. It also shows that designed climate change experiments coupled with genome sequencing offer great potential to test for the occurrence (or lack) of an evolutionary response.

Spatial patterns and controls on burned area for two contrasting fire regimes in Southern California N. R. Faivre, 1, † Y. Jin, 2 M. L. Goulden, 1 and J. T. Randerson 1 1 Department 2 Department of Earth System Science, University of California, Irvine, California 92697-3100 USA of Land, Air and Water Resources, University of California, Davis, California 95616-8627 USA Citation: Faivre, N. R., Y. Jin, M. L. Goulden, and J. T. Randerson. 2016. Spatial patterns and controls on burned area for two contrasting fire regimes in Southern California. Ecosphere 7(5):e01210. 10.1002/ecs2.1210 Abstract. An improved understanding of the mechanisms that regulate wildfire risk at local to regional scales is needed for the design of effective fire and ecosystem management. We investigated the spatial distribution of burned area in Southern California during 1960–2009 using five different data-­driven meth- ods: multiple linear regression, generalized additive models (GAMs), GAMs with spatial autocorrelation, non-­linear multiplicative models, and random forest models. We used each method to separately develop burned area risk maps for Southern California’s two distinct wildfire regimes: Santa Ana (SA fires), which occur during high wind events mostly in autumn, and non-­Santa Ana fires (non-­SA fires), which occur mostly during the hot and dry Mediterranean-­climate summer. The different methods explained 38–63% of the spatial variance in burned area for SA fires and 21–48% for non-­SA fires. The two fire regimes had contrasting drivers, with Fosberg fire weather index, relative humidity, minimum temperature, and dis- tance to housing most important for SA fires, and shrub cover, road density, and distance to minor and major roads most important for non-­SA fires. Our modeling framework carries implications for the strate- gic placement of fire suppression resources, and for prevention planning in areas facing increasing human and climate pressures. Key words: biophysical drivers; fire frequency; geospatial regression models; human influence; Mediterranean ­ecosystems; Santa Ana fires; wildfire risk; wildland–urban interface. Received 22 July 2015; accepted 29 July 2015. Corresponding Editor: D. P. C. Peters. Copyright: © 2016 Faivre et al. This is an open access article under the terms of the Creative Commons Attribution ­License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. † E-mail: belotte.faivre@gmail.com I ntroduction loss and multiple fatalities (Brillinger et al. 2009, Keeley et al. 2009). Spatial and temporal variabil- ity in burned area within the region depends on ignition, meteorology, vegetation characteristics, topography, and fire suppression (Davis and Mi- chaelsen 1995, Zedler and Seiger 2000, Moritz et al. 2004). Large areas of wildland–urban inter- face further contribute to variability in burned area as a consequence of ignition probability, landscape fragmentation, and access points for suppression. Interactions between the envi- ronmental and human controls on wildfire are Southern California is prone to recurrent wild- land fire that strongly influences ecosystem pro- cesses and vegetation dynamics. Over the past 50 yr, an average of 40 large fires (>40 ha each) occurred each year, resulting in a mean burned area of 53 300 ha per yr (Jin et al. 2014). Despite considerable investment in fire suppression, fire perimeter data sets show an increasing trend in burned area since 1980 (Westerling 2006, Jin et al. 2014). These fires have caused extensive property v www.esajournals.org May 2016 v Volume 7(5) v Article e01210

© 2015 IOP Publishing Ltd. The area burned by Southern California wildfires has increased in recent decades, with implications for human health, infrastructure, and ecosystem management. Meteorology and fuel structure are universally recognized controllers of wildfire, but their relative importance, and hence the efficacy of abatement and suppression efforts, remains controversial. Southern California's wildfires can be partitioned by meteorology: fires typically occur either during Santa Ana winds (SA fires) in October through April, or warm and dry periods in June through September (non-SA fires). Previous work has not quantitatively distinguished between these fire regimes when assessing economic impacts or climate change influence. Here we separate five decades of fire perimeters into those coinciding with and without SA winds. The two fire types contributed almost equally to burned area, yet SA fires were responsible for 80% of cumulative 1990-2009 economic losses ($3.1 Billion). The damage disparity was driven by fire characteristics: SA fires spread three times faster, occurred closer to urban areas, and burned into areas with greater housing values. Non-SA fires were comparatively more sensitive to age-dependent fuels, often occurred in higher elevation forests, lasted for extended periods, and accounted for 70% of total suppression costs. An improved distinction of fire type has implications for future projections and management. The area burned in non-SA fires is projected to increase 77% (±43%) by the mid-21st century with warmer and drier summers, and the SA area burned is projected to increase 64% (±76%), underscoring the need to evaluate the allocation and effectiveness of suppression investments.