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Mountains are strongly seasonal habitats, which require special adaptations in wildlife species living on them. Population dynamics of mountain ungulates are largely determined by the availability of rich food resources to sustain lactation and weaning during summer. Increases of temperature affect plant phenology and nutritional quality. Cold-adapted plants occurring at lower elevations will shift to higher ones, if available. We predicted what could happen to populations of mountain ungulates based on how climate change could alter the distribution pattern and quality of high-elevation vegetation, using the “clover community-Apennine chamoisRupicapra pyrenaica ornata” system. From 1970 to 2014, increasing spring temperatures (2 °C) in our study area led to an earlier (25 days) onset of green-up in Alpine grasslands between 1700 and 2000 m, but not higher up. For 1970–2070, we have projected trends of juvenile winter survival of chamois, by simulating trajectories of spring temperatures and occurrence of clover, through models depicting four different scenarios. All scenarios have suggested a decline of Apennine chamois in its historical core range, during the next 50 years, from about 28% to near-extinction at about 95%. The negative consequences of climate changes presently occurring at lower elevations will shift to higher ones in the future. Their effects will vary with the species-specific ecological and behavioural flexibility of mountain ungulates, as well as with availability of climate refugia. However, global shifts in distributional ranges and local decreases or extinctions should be expected, calling for farsighted measures of adaptive management of mountain-dwelling herbivores.

With the increased production and research on nanoparticles, the presence of carbon nanotubes (CNTs) in aquatic systems is very likely to increase. Although it has been shown that CNTs may cause toxicity in marine organisms, to our knowledge, the possible impacts under global temperature increase is still unknown. For this reason, biochemical and physiological impacts induced in Mytilus galloprovincialis due to the presence of functionalized multi-walled CNTs (f-MWCNTs) and increased temperature were investigated in the present study. The mussels exposed to increased temperature alone presented higher metabolic capacity and expenditure of glycogen as an energy resource to fuel up defense mechanisms and thus preventing oxidative damage. Contrarily, organisms exposed to f-MWCNTs alone seemed not stressed enough to demonstrate differences in the metabolism capacity. Furthermore, f-MWCNTs seemed not able to significantly activate their antioxidant and biotransformation enzymes, which in turn may led to oxidative damage in the cells especially when organisms were exposed to a warmer temperature. In fact, at higher temperature, the antioxidant response of organisms exposed to f-MWCNTs was not effective and oxidative damage levels were observed. Nevertheless, no additive or synergetic effects were observed when mussels were exposed to both stressors simultaneously.

Grassland provides high nutritive forages for ruminants being a main factor in feeding beef and especially dairy cattle. Changes in precipitation patterns, asides rising temperature and CO2 concentration, will severely affect forage species and modify the nutritive value, and this in turn will also impact animal performance. The aim of this study was to evaluate the influence of water stress on agronomic parameters and the nutritive value of orchard grass (Dactylis glomerata L.) in mountainous permanent grassland, under i) ambient (C0T0) and ii) future (C2T2) climate conditions with increased temperature (+3 °C) and elevated CO2 (+300 ppm). To simulate water stress, a drought experiment was conducted during the experimental period. The experiment took place at the Agricultural Research and Education Centre (AREC) Raumberg-Gumpenstein in Styria (Austria) from 2016 to 2018. Experimental plots were harvested in a 3-cut-system and plant samples were analysed for development stage, leaf weight ratio (LWR) and tiller height and weight. The nutritive value was determined by analysing crude protein (CP) and its fractionation, water-soluble carbohydrates (WSC), NDForg, ADForg, metabolizable energy (ME) and digestibility of organic matter (DOM), among others. The results showed that water stress did not alter the development stage of orchard grass, but decreased tiller height and weight under ambient climate conditions. Furthermore, an increase in ME and DOM, and a decrease in NDForg and ADForg occurred under water stress. In combination with elevated temperature and CO2, water stress improved CP, WSC, ME and DOM, and decreased NDForg and ADForg. Conclusively, water stress improved specific nutritive parameters but, in some circumstances, caused a decline in biomass production.

The present paper examines the evolution of Romanian seaside tourism between 2008–2018 to find the connection between climate change and the number of total tourist arrivals. The vicious cycle of greenhouse gas emissions and climate change has become one of the most critical topics discussed due to its negative effect on the wellbeing of the planet and its impact on sustainable economic development in the long run. Various economic activities, including tourism, could be subject to dramatic changes due to global warming. Depending on the geographical location of tourist destinations, and the degree of fluctuation in climate indicators, there have been dramatic shifts in visitor flow. This situation has been aggravated as countries that were once famous for their summer season and seaside holidays are now affected by high temperatures. Such temperatures can hardly be tolerated by tourists, particularly those from the Nordic countries. By comparison, there are countries that have been known to have only two or three full summer months suitable for tourism at the seaside and which in the last years have had a more extended summer season. This situation could turn into a significant competitive regional economic advantage for countries such as Romania, at least in the short- and medium-term. In this context, we aim to investigate whether there are climatic conditions, such as the extension of the tourist season on the coast (in the case of destinations that have four seasons and are known for having a shorter number of summer days), that can be turned into advantages. In this regard, we have conducted exploratory research to analyse if there is a statistically significant correlation between the indicators regarding climate change and tourism arrivals on the Romanian seaside, namely Constanta county. For our study, we used secondary data, provided by the Romanian National Meteorological Administration and the National Institute of Statistics, and accumulated a detailed profile of Romanian seaside summer tourism in the context of actual climate changes and challenges. Climate change may have significant consequences on the tourism industry and economic growth as well. Information on the direct effects higher temperatures could have on tourism is lacking. Improving policy analysis is necessary to reduce uncertainties, further understanding, assess implications and enable the tourism industry to adapt to changing circumstances.

Year to year change in weather poses serious threats to agriculture globally, especially in developing countries. Global climate models simulate an increase in global temperature between 2.9 to 5.5 &deg, C till 2060, and crop production is highly vulnerable to climate warming trends. Extreme temperature causes a significant reduction in crop yields by negatively regulating the crop phenology. Therefore, to evaluate warming impact on cotton (Gossypium hirsutum L.) production and management practices, we quantified agrometeorological data of 30 years by applying multiple crop modelling tools to compute the expected rise in temperature, impact of crop phenology, yield loss, provision of agrometeorology-services, agronomic technologies, and adaptation to climate-smart agriculture. Model projections of 15 agrometeorology stations showed that the growing duration of the sowing-boll opening and sowing-harvesting stages was reduced by 2.30 to 5.66 days decade&minus, 1 and 4.23 days decade&minus, 1, respectively, in Pakistan. Temperature rise in China also advanced the planting dates, sowing emergence, 3&ndash, 5 leaves, budding anthesis, full-bloom, cleft-boll, boll-opening, and boll-opening filling by 24.4, 26.2, 24.8, 23.3, 22.6, 15.8, 14.6, 5.4, 2.9, and 8.0 days. Furthermore, present findings exhibited that the warming effect of sowing-harvest time was observed 2.16 days premature, and delayed for 8.2, 2.4, and 5.3 days in the 1970s, 1980s, and 1990s in China. APSIM-cotton quantification revealed that the sowing, emergence, flowering, and maturity stages were negatively correlated with temperature &minus, 2.03, &minus, 1.93, &minus, 1.09, and &minus, 0.42 days &deg, C&minus, 1 on average, respectively. This study also provided insight into the adaptation of smart and better cotton by improving agrotechnological services.

Aim To determine the internal P loading potential of semiarid tropical reservoir sediment while verifying the driving factors that affect P release rates. Methods An experiment was performed with water and sediment from the reservoir Boqueirão de Parelhas in Brazil. The effects of three variables on P release were studied: air temperature (region average of 28 °C and 32 °C, simulating an increase of 4 °C), pH (region average of pH 8, more acidic pH 6 and more alkaline pH 10) and oxygen (presence and absence). In addition, P fractionation analysis was performed on the P forms in the sediment. Results It was found that the minimum P release was in an oxic treatment at pH 6 and temperature 28 °C (0.22 mg m-2 d-1 ± 0.13) and the maximum P release in an anoxic treatment at pH 10 and temperature 32 °C (2.1 mg m-2 d-1 ± 0.15). The total P in the sediment was 597 mg kg-1, and the major P form in the sediment was NaOH-rP, the P bound to aluminum, corresponding to 42% of the total P. Conclusion These results allow us to confirm that the sediment of the Boqueirão reservoir is susceptible to the release of P bound to aluminum due to the prevalence of this form in its sediments concomitant with the high temperatures and alkaline pH of the water. This scenario can be aggravated by climate change. Resumo: Objetivo Determinar o potencial de fertilização interna de P do sedimento de reservatório tropical semiárido, ao mesmo tempo em que verificar os fatores que afetam as taxas de liberação de P. Métodos Foi realizado um experimento com água e sedimento do reservatório Boqueirão de Parelhas, Brasil. Foram estudados os efeitos de três variáveis na liberação de P: temperatura do ar (região média de 28 °C e 32 °C, simulando aumento de 4 °C), pH (região média de pH 8, pH mais ácido 6 e pH mais alcalino 10) e oxigênio (presença e ausência). Além disso, a análise de fracionamento de P foi realizada nas formas de P no sedimento. Resultados Verificou-se que a liberação mínima de P foi em tratamento óxico em pH 6 e temperatura 28 °C (0,22 mg m-2 d-1 ± 0,13) e a liberação máxima de P em tratamento anóxico em pH 10 e temperatura 32 °C (2,1 mg m-2 d-1 ± 0,15). O P total no sedimento foi 597 mg kg-1, e a principal forma de P no sedimento foi o NaOH-rP, o P ligado ao alumínio, correspondendo a 42% do P total. Conclusão Esses resultados nos permitem confirmar que o sedimento da represa do Boqueirão é suscetível à liberação de P ligado ao alumínio devido ao predomínio desta forma em seus sedimentos concomitante às altas temperaturas e pH alcalino da água. Esse cenário pode ser agravado pelas mudanças climáticas.

Drinking water distribution systems (DWDSs) have been thoroughly studied, but the concept of thermal energy recovery from DWDSs is very new and has been conceptualized in the past few years. Cold recovery results in a temperature increase of the drinking water. Its effects on drinking water quality and biofilm development are unclear. Hence, we studied both bulk water and biofilm phases for 232 days in two parallel pilot scale distribution systems with two temperature settings after cold recovery, 25 °C and 30 °C, and compared these with a reference pilot system without cold recovery. In all three pilot distributions systems (DSs) our results showed an initial increase in biomass (ATP) in the biofilm phase, along with occurrence of primary colonizers (Betaproteobacteriales) and subsequently a decrease in biomass and an increasing relative abundance of other microbial groups (amoeba resisting groups; Xanthobacteraceae, Legionellales), including those responsible for EPS formation in biofilms (Sphingomonadaceae). The timeline for biofilm microbial development was different for the three pilot DSs: the higher the temperature, the faster the development took place. With respect to the water phase within the three pilot DSs, major microbial contributions came from the feed water (17–100%) and unkown sources (2–80%). Random contributions of biofilm (0–70%) were seen between day 7–77. During this time period six-fold higher ATP concentration (7–11 ng/l) and two-fold higher numbers of high nucleic acid cells (5.20–5.80 × 104 cells/ml) were also observed in the effluent water from all three pilot DSs, compared to the feed water. At the end of the experimental period the microbial composition of effluent water from three pilot DSs revealed no differences, except the presence of a biofilm related microbial group (Sphingomonadaceae), within all three DSs compared to the feed water. In the biofilm phase higher temperatures initiated the growth of primary colonizing bacteria but this did not lead to differences in microbial diversity and composition at the end of the experimental period. Hence, we propose that the microbiological water quality of DWDSs with cold recovery should be monitored more frequently during the first 2–3 months of operation.

Terrestrial biomes are the main reservoirs of biodiversity and CO2 on the planet. In South America, they play a crucial role in climate regulation and biodiversity conservation. Despite scientific advances and recent efforts, there is still no detailed analysis of trends in surface air temperature and precipitation changes until the end of the 21st century and magnitude of change for South America’s terrestrial biomes. In this study, we used the annual mean of temperature and annual cumulative precipitation variables provided by WorldClim (version 2.1) from an ensemble of five Global Circulation Models from the most recent simulations of the CMIP6 project. We used four-time intervals between 2020 and 2100, combined at two climatic trajectories (SSP2-4.5 and SSP5-8.5), to map climate change scenarios’ trend magnitude in South America. Also, we evaluate the exposure level of the nine terrestrial biomes according to their respective vegetal cover densities. Our results indicate that in the two possible futures evaluated (SSP2-4.5 & SSP5-8.5), the terrestrial biomes of South America would be exposed to climatic conditions that are not analogous to the current ones. The results indicate a persistent and long-term annual temperature trend increase, indistinctly for all terrestrial biomes and a significant moisture reduction in forest biomes. The consolidation of such climate scenarios can make potentially modify water and carbon cycling patterns and promoting biodiversity loss, mainly at forest biomes, with probably more severe effects under the pessimistic scenario.

In the Mediterranean basin the effects of climate warming on ecosystem functioning will strongly depend on the warming intensity directly but also on its effects on evapotranspiration and nutrient cycling. Climate manipulation experiments under field conditions are a source of unique empirical evidence regarding climate-related modifications of biotic processes. A field night-time warming experiment, simulating the predicted near-future increase in ambient temperatures (+0.3 up to 1 °C), was established in a Mediterranean shrub community located in Porto Conte (Italy) in 2001. After 11 years of continuous treatment, we labeled the dominant shrub Cistus monspeliensis with 13CO2 and studied the dynamics of the label allocation between aboveground and belowground pools and fluxes in warmed and ambient plots within 2 weeks of the chasing period. The interactions between C and N metabolism were assessed by parallel labeling of soil with K15NO3. Most of the assimilated 13C was respired by Cistus shoots (28–51%) within two weeks. Cistus under warming respired more 13C label and tended to allocate less 13C to leaves, branches and roots. The higher C and N content in microbial biomass in warming plots, combined with the higher N content in plant tissues and soil, evidenced a greater N mobilization in soil and a better nutrient status of the plants as compared to the ambient treatment. Acceleration of N cycling is probably responsible for higher respiratory C losses, but combined with the reduction in the number of frost days, should also positively affect plant photosynthetic performance. We conclude that, although Cistus plants are already growing in conditions close to their thermal optimum, long-term warming will positively affect the performance of this species, mainly by reducing the nutrient constraints. This positive effect will highly depend on the frequency and amount of rain events and their interactions with soil N content.

Ectomycorrhizal (ECM) fungi can influence the establishment and performance of host species by increasing nutrient and water absorption. Therefore, understanding the response of ECM fungi to expected changes in the global climate is crucial for predicting potential changes in the composition and productivity of forests. While anthropogenic activity has, and will continue to, cause global temperature increases, few studies have investigated how increases in temperature will affect the community composition of ectomycorrhizal fungi. The effects of global warming are expected to be particularly strong at biome boundaries and in the northern latitudes. In the present study, we analyzed the effects of experimental manipulations of temperature and canopy structure (open vs. closed) on ectomycorrhizal fungi identified from roots of host seedlings through 454 pyrosequencing. The ecotonal boundary site selected for the study was between the southern boreal and temperate forests in northern Minnesota, USA, which is the southern limit range for Picea glauca and Betula papyrifera and the northern one for Pinus strobus and Quercus rubra. Manipulations that increased air and soil temperature by 1.7 and 3.4 °C above ambient temperatures, respectively, did not change ECM richness but did alter the composition of the ECM community in a manner dependent on host and canopy structure. The prediction that colonization of boreal tree species with ECM symbionts characteristic of temperate species would occur was not substantiated. Overall, only a small proportion of the ECM community appears to be strongly sensitive to warming. Electronic supplementary material The online version of this article (doi:10.1007/s00248-017-1044-5) contains supplementary material, which is available to authorized users.

Realistic predictions of climate change effects on natural resources are central to adaptation policies that try to reduce these impacts. However, most current forecasting approaches do not incorporate species-specific, process-based biological information, which limits their ability to inform actionable strategies. Mechanistic approaches, incorporating quantitative information on functional traits, can potentially predict species- and population-specific responses that result from the cumulative impacts of small-scale processes acting at the organismal level, and can be used to infer population-level dynamics and inform natural resources management. Here we present a proof-of-concept study using the European anchovy as a model species that shows how a trait-based, mechanistic species distribution model can be used to explore the vulnerability of marine species to environmental changes, producing quantitative outputs useful for informing fisheries management. We crossed scenarios of temperature and food to generate quantitative maps of selected mechanistic model outcomes (e.g., Maximum Length and Total Reproductive Output). These results highlight changing patterns of source and sink spawning areas as well as the incidence of reproductive failure. This study demonstrates that model predictions based on functional traits can reduce the degree of uncertainty when forecasting future trends of fish stocks. However, to be effective they must be based on high spatial- and temporal resolution environmental data. Such a sensitive and spatially explicit predictive approach may be used to inform more effective adaptive management strategies of resources in novel climatic conditions.

Destabilization of intrapermafrost gas hydrate is one possible reason for methane emission on the Arctic shelf. The formation of these intrapermafrost gas hydrates could occur almost simultaneously with the permafrost sediments due to the occurrence of a hydrate stability zone after sea regression and the subsequent deep cooling and freezing of sediments. The top of the gas hydrate stability zone could exist not only at depths of 200&ndash, 250 m, but also higher due to local pressure increase in gas-saturated horizons during freezing. Formed at a shallow depth, intrapermafrost gas hydrates could later be preserved and transform into a metastable (relict) state. Under the conditions of submarine permafrost degradation, exactly relict hydrates located above the modern gas hydrate stability zone will, first of all, be involved in the decomposition process caused by negative temperature rising, permafrost thawing, and sediment salinity increasing. That&rsquo, s why special experiments were conducted on the interaction of frozen sandy sediments containing relict methane hydrates with salt solutions of different concentrations at negative temperatures to assess the conditions of intrapermafrost gas hydrates dissociation. Experiments showed that the migration of salts into frozen hydrate-containing sediments activates the decomposition of pore gas hydrates and increase the methane emission. These results allowed for an understanding of the mechanism of massive methane release from bottom sediments of the East Siberian Arctic shelf.

International audience; Increases in tree mortality rates have been highlighted in different biomes over the past decades. However, disentangling the effects of climate change on the temporal increase in tree mortality from those of management and forest dynamics remains a challenge. Using a modelling approach taking tree and stand characteristics into account, we sought to evaluate the impact of climate change on background mortality for the most common European tree species. We focused on background mortality, which is the mortality observed in a stand in the absence of abrupt disturbances, to avoid confusion with mortality events unrelated to long-term changes in temperature and rainfall. We studied 372 974 trees including 7312 dead trees from forest inventory data surveyed across France between 2009 and 2015. Factors related to competition, stand characteristics, management intensity, and site conditions were the expected preponderant drivers of mortality. Taking these main drivers into account, we detected a climate change signal on 45% of the 43 studied species, explaining an average 6% of the total modelled mortality. For 18 out of the 19 species sensitive to climate change, we evidenced greater mortality with increasing temperature or decreasing rainfall. By quantifying the mortality excess linked to the current climate change for European temperate forest tree species, we provide new insights into forest vulnerability that will prove useful for adapting forest management to future conditions.

The stability and balance of forest ecosystems have been seriously affected by climate change. Herein, we use dendrochronological methods to investigate the radial growth and climate response of pioneer tree species in the southern margin of cold temperate coniferous forest based on Populus davidiana growing on the Greater Hinggan Mountains in northeastern China. Correlations of P. davidiana growth with temperature and precipitation in a year (October–September) were rhythmically opposed: while temperatures in previous October–June (winter and spring) and in May–September (growing season) respectively inhibited and promoted radial growth on P. davidiana (p < 0.01), precipitation in the same periods respectively promoted and inhibited of growth (p < 0.01). High temperature or less rain/snow in winter and early spring, and low temperature or excess rainfall in summer, are inconducive to P. davidiana growth and vice versa (p < 0.01). In addition, in March–April, when air temperature was above 0 °C and ground temperature below 0 °C, physiological drought caused significant growth inhibition in P. davidiana (p < 0.05). In general, temperatures play a driving and controlling role in the synergistic effect of temperature and precipitation on P. davidiana growth. Under current conditions of available water supply, changes of temperature, especially warming, are beneficial to the growth of P. davidiana in the study area. The current climate conditions promote the growth of P. davidiana, the pioneer species, compared with the growth inhibition of Larix gmelinii, the dominant species. Thus, the structure and function of boreal forest might be changed under global warming by irreversible alterations in the growth and composition of coniferous and broadleaf tree species in the forest.

This study aimed to determine the effect of using acrylonitrile butadiene styrene in place of conventional wax material on treatment pattern removal in the investment casting process. There are three controllable process variables that can affect treatment pattern removal, which include temperature increase, holding time and the number of layers of ceramic shell that have been considered for comparison. Comparison among the effects of temperature increase, holding time and numbers of ceramic shell layers on the ceramic shell was analyzed using ANOVA. It was found that temperature increase (Tx), holding time (t) and number of layers of ceramic shell (N) contribute significantly to the length of the crack (l) on the ceramic shell. The crack in the ceramic shell’s surface was analyzed using scanning electron microscope photos. Less layers number cause the increase of crack length. The combination between temperature upraise and longer holding time cause cracking delay. The experimental is conducted by using 3 (three) variants for each of layers number, temperature and holding time. The layers number is ranging between 7-9 layers. Temperature increase from room temperature until 1300oC. The layers number variant is ranging between 180-300 seconds. It was concluded that a longer holding time will result in a more intact ceramic shell, as longer holding times yield short crack lengths.

7 pages, 2 figures, 2 tables, supplementary data https://doi.org/10.1016/j.ecss.2020.107099, We built a simulation model based on Dynamic Energy Budget theory (DEB) to assess the growth and reproductive potential of the Manila clam Ruditapes philippinarum under different temperature and pH conditions, based on environmental values forecasted for the end of the 21st c. under climate change scenarios. The parameters of the DEB model were calibrated with the results of seasonal growth experiments under two levels of temperature (ambient and plus 2–3 °C) and three levels of pH (8.1 used as control and 7.7 and 7.3 representing acidification). The results showed that R. philippinarum is expected to have moderate growth in length or individual body mass (ultimate length and body weight would be larger than current values by 2–3%) when taking into account only the effect of temperature increase. However, acidification is likely to have a deleterious effect on growth, with a decrease of 2–5% length or body weight under the pH value of 7.7 forecasted for the end of the 21st c, or 10–15% under a more extreme scenario (pH = 7.3). However, the aggregated reproductive potential, integrated along a lifetime of 10 years, is likely to increase by 30% with temperature increase. Decreasing pH would impact negatively on reproductive potential, but in all simulations under warmer conditions, reproductive potential values were higher than current, suggesting that temperature increase would compensate losses due to acidification. The results are discussed in relation to their possible impact on aquaculture and fisheries of this important commercial bivalve, This research is part of the CERES project (European Commission H2020 Framework, contract nº 678193). The Spanish Ministry of Economy, Industry and Competitiveness contributed through the project AimCost CGL-2016-76332-R MINECO/FEDER/UE), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

Intertidal mussel species are frequently exposed to changes of environmental parameters related to tidal regimes that include a multitude of stressors that they must avoid or tolerate by developing adaptive strategies. In particular, besides air exposure during low tides, intertidal mussels are also subjected to warming and, consequently, to higher risk of desiccation. However, scarce information is available regarding the responses of mussels to tidal regimes, particularly in the presence of other stressors such as increased temperature. Investigating the impacts of such combination of conditions will allow to understand the possible impacts that both factors interaction may generate to these intertidal organisms. To this end, the present study evaluated the impacts of different temperatures (18 ºC and 21 ºC) on Mytilus galloprovincialis when continuously submersed or exposed to a tidal regime for 14 days. Results showed that in mussels exposed to increased temperature under submersion conditions, the stress induced was enough to activate mussels’ antioxidant defenses (namely glutathione peroxidase, GPx), preventing oxidative damage (lipid peroxidation, LPO; protein carbonylation, PC). In mussels exposed to tides at control temperature, metabolic capacity increased (electron transport system activity, ETS), and GPx was induced, despite resulting in increased LPO levels. Moreover, the combination of tides and temperature increase led to a significant decrease of lipid (LIP) content, activation of antioxidant defenses (superoxide dismutase, SOD; GPx) and increase of oxidized glutathione (GSSG), despite these mechanisms were not sufficient to prevent increased cellular damage. Therefore, the combination of increased temperature and air exposure induced higher oxidative stress in mussels. These findings indicate that increasing global warming could be more impacting to intertidal organisms compared to organisms continuously submersed. Furthermore, our results indicate that air exposure can act as a confounding factor when assessing the impacts of different stressors in organisms living in coastal systems published

Global warming is affecting ecosystems worldwide, with mountainous regions particularly vulnerable. At mid-altitudes, changes in winter precipitation will have immediate effects on lake fun...

International audience; Temperature is a key parameter of anaerobic digestion. Its modification can have drastic consequences on microbial communities and performances. However it can be an interesting parameter to adjust the productivity, energy efficiency or stability of bioreactors. The objective of this work was to give insights into the consequences of abrupt temperature modifications on the microbiota of anaerobic digestion. Two complementary experiments were performed. A continuously stirred lab-scale bioreactor (5-L) simulated the functioning of a semi-continuous industrial digester. Five batch-fed incubations (1-L) served as replicated experiments. Each experiment was divided into three successive steps: reactors were first operated at 35 degrees C followed by an abrupt increase to 55 degrees C and finally a decrease to 35 degrees C. After the first temperature shock, gas production rate increased temporarily and then fell for 1 month before a new steady-state was reached. When temperature was reset to 35 degrees C in step 3 gas production decreased sharply again. The semi-continuous reactor recovered after 15 days while the batch-fed incubations never recovered. Ecological changes associated to these performance drops and recovery were sought using 16S sequencing of Bacteria and Archaea and multivariate analyses. In brief, Bacteroidales order was rapidly and strongly affected by temperature increase, while Clostridiales became dominant in thermophilic conditions. Several thermotolerant Bacteria were identified as responsible for reactors early recovery, but were outcompeted by a very diverse bacterial population a few weeks after temperature shock. Methanosarcina and Methanobacterium Archaea dominated at 35 degrees C but were slowly replaced by thermophilic Methanoculleus or Methanosarcina at 55 degrees C that were essential to methane production. In step 3, when returning to initial temperature conditions after the thermophilic period, Ruminococcaceae and Methanobacterium appeared to drive digester resilience.

This work evaluates the experimental warming effects on phenology and grain yield components of wheat in the Yaqui Valley, Sonora, México, using CIRNO C2008 variety fromTriticum durumL., as a model during the cropping cycle of 2016–2017 (December to April). Infrared radiators were deployed to induce experimental warming by 2 °C above ambient crop canopy temperature, in a temperature free-air controlled enhancement system. Temperature was controlled by infrared temperature sensors placed in eight plots which covered a circle ofr= 1.5 m starting five days after germination until harvest. The warming treatment caused a reduction of phenophases occurrence starting at the stem extension phenophase. Such phenological responses generated a significant biological cycle reduction of 14 days. Despite this delay, CIRNO C2008 completed its biological cycle adequately. However, plant height under the warming treatment was reduced significantly and differences were particularly observed at the final phenophases of the vegetative cycle. Plant height correlated negatively with spikes length, spikes mass, and number of filled grains. Warming also reduced grain yield in 33%. The warming treatment caused a stress intensity (SI = 1-yield warming/yield control) of 39.4% and 33.2% in biomass and grain yield, respectively. The differences in stress intensities between biomass and grain yield were based on plant height reduction. Grain mass was not affected, demonstrating the crop capability for remobilization and adequate distribution of elaborated substances for the spikes under warming conditions.

This article is part of the FORHOT project, Increasing temperatures can accelerate soil organic matter decomposition and release large amounts of CO2 to the atmosphere, potentially inducing positive warming feedbacks. Alterations to the temperature sensitivity and physiological functioning of soil microorganisms may play a key role in these carbon (C) losses. Geothermally active areas in Iceland provide stable and continuous soil temperature gradients to test this hypothesis, encompassing the full range of warming scenarios projected by the Intergovernmental Panel on Climate Change for the northern region. We took soils from these geothermal sites 7 years after the onset of warming and incubated them at varying temperatures and substrate availability conditions to detect persistent alterations of microbial physiology to long-term warming. Seven years of continuous warming ranging from 1.8 to 15.9 °C triggered a 8.6–58.0% decrease on the C concentrations in the topsoil (0–10 cm) of these sub-arctic silt-loam Andosols. The sensitivity of microbial respiration to temperature (Q10) was not altered. However, soil microbes showed a persistent increase in their microbial metabolic quotients (microbial respiration per unit of microbial biomass) and a subsequent diminished C retention in biomass. After an initial depletion of labile soil C upon soil warming, increasing energy costs of metabolic maintenance and resource acquisition led to a weaker capacity of C stabilization in the microbial biomass of warmer soils. This mechanism contributes to our understanding of the acclimated response of soil respiration to in situ soil warming at the ecosystem level, despite a lack of acclimation at the physiological level. Persistent increases in the respiratory costs of soil microbes in response to warming constitute a fundamental process that should be incorporated into climate change-C cycling models., This research was supported by the European Union’s Seventh Framework Program, the Ministry of Economy, Innovation, Science and Employment of the Junta de Andalucía (postdoctoral fellowship of the Andalucía Talent Hub Program, Marie Skłodowska-Curie actions, COFUND—Grant Agreement No 291780, to SMJ), the European Research Council Synergy grant 610028 (IMBALANCE-P), the research project “GEISpain” (CGL2014-52838-C2-1-R) of the Spanish Ministry of Economy and Competitiveness and the Research Council of the University of Antwerp (FORHOT TOP-BOF project). This work contributes to the FSC-Sink, CAR-ES and ClimMani COST Action (ES1308). The Agricultural University of Iceland and Mogilsá—the Icelandic Forest Research, provided logistical support for the present study. We thank Matthias Meys, Sara Diels, Johan De Gruyter, Giovanni Dalmasso, Fabiana Quirós and Nadine Calluy for their invaluable help in the laboratory and Sara Vicca and James Weedon for their constructive suggestions. We further thank Anne Cools and Tom Van Der Spiet for their assistance with the lab chemical analyses.

Shellfish aquaculture represents a worldwide valuable segment of the aquaculture market, spreading along the Mediterranean coasts, and is sensitive to the still unforeseen, poorly-known effects of climate change. Threats due to temperature rise can threaten the deployment and development of this sector, up until now recognised as the best candidate to mitigate the effects of fishery overexploitation. Here, we investigate the effects of temperature increase on the model species, Mytilus galloprovincialis, measuring outcomes from valve fragility (thickness) and condition index. Evidence of a reduction in the thickness of valves and the modulation condition of the mussels along with temperature increase have been gathered from simulations of a natural temperature gradient changing along latitude (the Italian Peninsula) and temperature risen (mesocosm trial). The obtained results offer a baseline to help the next generation of managers and stakeholders when assessing the reliability and feasibility of shellfish culture in a changing sea that can generate undetected and underestimated impacts on the sector.

Conference of 16th IEEE SENSORS Conference, ICSENS 2017 ; Conference Date: 30 October 2017 Through 1 November 2017; Conference Code:132067; International audience; Nowadays, the safety of passengers on board is the first preoccupation for aircraft manufacturers. For this reason, next-generation helicopters are now being designed with a wide range of advanced technologies to reinforce safety. In this context, a new fire detection system based on reflectometry is proposed for monitoring the engines of helicopters. The main idea is to mesh engines by a fireproof cable that serves not only as a physical support of test signals, but also as a fire detection sensor. To do so, OMTDR technology is integrated into an electronic device analyzing in permanence the impedance variation of the sensor caused by a temperature increase. The proposed fire detection system permits not only to detect the fire as conventional systems, but also to locate it with accuracy. Moreover, the fire detection sensor becomes intelligent since it is able to self-diagnosis (i.e. hard fault, aging, etc.) thanks to OMTDR use. For feasibility proof, a demonstrator is developed and tested in laboratory. Experimental results show that the fire detection system is able to detect and locate multiple fire zones simultaneously without loss of accuracy.

The paper deals with the comparison of the tem- perature increase due to a high frequency exposure in two realistic human eye models. The first model of the human eye, named extracted eye model is placed in the free space, while the second model of the eye, named compound eye model is included in the detailed human head model obtained from the magnetic resonance imaging scans. The numerical results are obtained using the hybrid finite element/boundary element method (FEM/BEM) formulation for the electromagnetic model, while the thermal dosimetry model based on the use of Pennes bioheat transfer equation is treated via FEM technique. Although qualitatively similar distributions of temperature increase have been obtained for both eye models, further analysis showed that the compound eye model is more suitable when the polarization of the incident EM wave is taken into account. On the other hand, the extracted eye model, due to much easier implementation compared to the compound model, can be found helpful when carrying out the preliminary dosimetric analysis.

Quinoa high nutritive value increases interest worldwide, especially as a crop that could potentially feature in different cropping systems, however, climate change, particularly rising temperatures, challenges this and other crop species. Currently, only limited knowledge exists regarding the grain yield and other key traits response to higher temperatures of this crop, especially to increased night temperatures. In this context, the main objective of this study was to evaluate the effect of increased night temperature on quinoa yield, grain number, individual grain weight and processes involved in crop growth under the environmental conditions (control treatment) and night thermal increase at two phases: flowering (T1) and grain filling (T2) in southern Chile. A commercial genotype, Regalona, and a quinoa accession (Cod. BO5, N°191, grain bank from Semillas Baer, hereby referred to as Accession) were used, due to their adaptability to Southern Chilean conditions and contrasting grain yield potential, grain weight and size of plants. Temperature was increased ≈4°C above the ambient from 8 pm until 9 am the next morning. Control treatments reached a high grain yield (600 and 397 g m-2, i.e., Regalona and Accession). Temperature increase reduced grain yield by 31% under T1 treatment and 12% when under T2 in Regalona and 23 and 26% in Accession, respectively. Aboveground biomass was negatively affected by the thermal treatments and a positive linear association was found between grain yield and aboveground biomass across treatments. By contrast, the harvest index was unaffected either by genotype, or by thermal treatments. Grain number was significantly affected between treatments and this key trait was linearly associated with grain yield. On the other hand, grain weight showed a narrow range of variation across treatments. Additionally, leaf area index was not affected, but significant differences were found in SPAD values at the end of T1 treatment, compared to control. Little change was found in the harvest index, individual grain weight, grain protein content or water soluble carbohydrates in response to the increased night temperature in this crop.

Extreme temperatures and heat wave trends in five cities within the Sonoran Desert region (e.g., Tucson and Phoenix, Arizona, in the United States and Ciudad Obregon and San Luis Rio Colorado, Sonora; and Mexicali, Baja California, in Mexico) and one city within the Mojave Desert region (e.g., Las Vegas, Nevada) were assessed using field data collected from 1950 to 2014. Instead of being selected by watershed, the cities were selected because they are part of the same arid climatic region. The data were analyzed for maximum temperature increases and the trends were confirmed statistically using Spearman’s nonparametric test. Temperature trends were correlated with the mortality information related with extreme heat events in the region. The results showed a clear trend of increasing maximum temperatures during the months of June, July, and August for five of the six cities and statically confirmed using Spearman’s rho values. Las Vegas was the only city where the temperature increase was not confirmed using Spearman’s test, probably because it is geographically located outside of the Sonoran Desert or because of its proximity to the Hoover Dam. The relationship between mortality and temperature was analyzed for the cities of Mexicali, Mexico and Phoenix. Arizona.

Destabilization of intrapermafrost gas hydrates is one of the possible mechanisms responsible for methane emission in the Arctic shelf. Intrapermafrost gas hydrates may be coeval to permafrost: they originated during regression and subsequent cooling and freezing of sediments, which created favorable conditions for hydrate stability. Local pressure increase in freezing gas-saturated sediments maintained gas hydrate stability from depths of 200&ndash, 250 meters or shallower. The gas hydrates that formed within shallow permafrost have survived till present in the metastable (relict) state. The metastable gas hydrates located above the present stability zone may dissociate in the case of permafrost degradation as it becomes warmer and more saline. The effect of temperature increase on frozen sand and silt containing metastable pore methane hydrate is studied experimentally to reconstruct the conditions for intrapermafrost gas hydrate dissociation. The experiments show that the dissociation process in hydrate-bearing frozen sediments exposed to warming begins and ends before the onset of pore ice melting. The critical temperature sufficient for gas hydrate dissociation varies from &minus, 3.0 to &minus, 0.3 &deg, C and depends on lithology (particle size) and salinity of the host frozen sediments. Taking into account an almost gradientless temperature distribution during degradation of subsea permafrost, even minor temperature increases can be expected to trigger large-scale dissociation of intrapermafrost hydrates. The ensuing active methane emission from the Arctic shelf sediments poses risks of geohazard and negative environmental impacts.

Climate changes will promote the growth of invasive aquatic macrophytes. The aim of our study was to analyse the responses of three invasive plants ( Elodea canadensis, Egeria densa and Lagarosiphon major ) to a temperature increase of 3 °C in spring, summer and winter. At each season we measured four functional traits: the Relative Growth Rate ‘RGR’, Relative Leaf surface area Growth Rate, number of lateral branches and roots. E. canadensis showed the highest growth and vigour in spring and in summer. The Relative Growth Rate was enhanced by an elevation of temperature for E. c anadensis and for E. densa . A 3 °C temperature increase stimulated root production for all species in summer, whereas the number of lateral branches was favoured in spring for E. canadensis . Climate warming had a greater impact on plant growth in spring than in summer and late winter. The response of species to climate warming was species-specific and so an increase in temperature should favour the spread of E. canadensis.

International audience; The purpose of this paper is to probe by infrared absorption spectroscopy and molecular dynamics simulations the evolution of the local order of sub- and supercritical water along the isobar 22 MPa and in the temperature range between 293 K and 693 K. Infrared absorption measurements were performed along this isobar using an isotopic water mixture of D2O and H2O with the molar ratio of 1:20 leading to a mixture of D2O, HOD and H2O with molar proportions of 1:40:400, respectively. The evolution of the shape of the infrared profiles associated with the O-D stretching mode of HOD and the combinations ν3 + ν2 and ν3 + ν1 of H2O reveal a progressive weakening upon the temperature increase of the hydrogen bond network existing in liquid water at room temperature. In order to get a molecular description of such experimental results, Molecular Dynamics simulations of water were performed using a cubic simulation box consisting of 864 water molecules modeled with the TIP4P potential in the (N,P,T) ensemble. We have characterized the local structure using the nearest neighbour radial and orientation distributions, the Voronoi polyhedral and the tetrahedral distributions of water molecules. Our results show that with increasing the temperature, the average distance between two water molecules increases, the local density around a water molecule decreases particularly when the temperature is close to the critical one and finally the tetrahedral distributions shift to lower values indicating the distortion of the tetrahedral distribution. These results correlate with the weakening of the hydrogen bond interaction between two water molecules and then to the shift of the OH vibration frequency to lower values in accordance with the infrared results.

Imbalance-P paper contact with: josep peñuelas: j.penuelas@uab.cat Wheat, rice, maize, and soybean provide two-thirds of human caloric intake. Assessing the impact of global temperature increase on production of these crops is therefore critical to maintaining global food supply, but different studies have yielded different results. Here, we investigated the impacts of temperature on yields of the four crops by compiling extensive published results from four analytical methods: global grid-based and local point-based models, statistical regressions, and field-warming experiments. Results from the different methods consistently showed negative temperature impacts on crop yield at the global scale, generally underpinned by similar impacts at country and site scales. Without CO2 fertilization, effective adaptation, and genetic improvement, each degree-Celsius increase in global mean temperature would, on average, reduce global yields of wheat by 6.0%, rice by 3.2%, maize by 7.4%, and soybean by 3.1%. Results are highly heterogeneous across crops and geographical areas, with some positive impact estimates. Multimethod analyses improved the confidence in assessments of future climate impacts on global major crops and suggest crop- and region-specific adaptation strategies to ensure food security for an increasing world population.

17 pages, 5 figures, 5 tables, supplementary material http://dx.doi.org/10.3354/cr01369, Although the deep sea is considered a relatively stable environment, it is affected by climatic and environmental variations with implications for functioning of its ecosystems and food webs. We used stable isotopes to compare trophic levels of 21 species of deep-sea megafauna (fish, decapods and other invertebrates) between 2 periods separated by ca. 20 yr (1985-1989 vs. 2007-2011) and characterized by different climatic conditions (based on the NAO index), by increases in temperature and salinity and by a decrease in O2 concentration in intermediate (Levantine Intermediate Waters, LIW) and deep (at the Benthic Boundary Layer, BBL) water masses in the Balearic Basin. We found a decrease in the δ15N of benthopelagic fishes (1.5‰ on average), benthic invertebrates (1.1‰) and pelagic organisms (0.8‰) from 1985-1989 to 2007-2011, a temporal decline confirmed with additional analyses performed after compiling published data collected in 1996, 1998, 2003/2004 and 2007/2008 from the same area. Changes in trophic levels (based on δ15N) were correlated (Spearman’s R) to temperature increase, i.e. species seemed to feed on lower trophic levels during warmer periods. According to generalized linear models, the main explanatory variables for changes in δ15N were O2 in the BBL and at the core of the LIW, chlorophyll a concentration at the surface and salinity near the bottom. We hypothesize that the changes in oceanographic conditions in the Mediterranean, driven by both global change and river damming, have influenced benthic organisms by reducing their biomass and/or size, shifting megafauna (mainly fish) to feed on more pelagic or smaller benthic prey, with lower δ15N values, in 2007-2011 compared to 1985-1989, This study was financed by the MICYT project ANTROMARE (CTM2009-12214-C02-01-MAR)

cited By 4; International audience; In the current work, the plasticity at room temperature, as well as the creep and stress relaxation behaviors at high temperature of the Ti16.7Zr16.7Hf16.7Cu16.7Ni16.7Be16.7 high-entropy bulk metallic glass have been investigated. In the compressive testing, the fracture strength can reach 2539 MPa at room temperature and the plasticity of the Ti16.7Zr16.7Hf16.7Cu16.7Ni16.7Be16.7 high-entropy metallic glass is better at the lower strain-rate. The creep property was studied by stress-jump tests at different temperatures. It is noted that the Newtonian behavior of the alloy would turn to non-Newtonian at high temperature with increasing of the strain rate. The apparent activation volume of Ti16.7Zr16.7Hf16.7Cu16.7Ni16.7Be16.7 high-entropy metallic glass is smaller than that of traditional metallic glasses. It is found that the heterogeneity of the alloy system will be enhanced as temperature increases near and below the glass transition temperature Tg. © 2016 Elsevier B.V.

International audience; Humanity is heading toward the major challenge of having to increase food production by about 50% by 2050 to cater for an additional three billion inhabitants, in a context of arable land shrinking and degradation, nutrient deficiencies, increased water scarcity, and uncertainty due to predicted climatic changes. Already today, water scarcity is probably the most important challenge, and the consensual prediction of a 2–4°C degree increase in temperature over the next 100years will add new complexity to drought research and legume crop management. This will be especially true in the semi-arid tropic areas, where the evaporative demand is high and where the increased temperature may further strain plant–water relations. Hence, research on how plants manage water use, in particular, on leaf/root resistance to water flow will be increasingly important. Temperature increase will variably accelerate the onset of flowering by increasing thermal time accumulation in our varieties, depending on their relative responses to day length, ambient, and vernalizing temperature, while reducing the length of the growing period by increasing evapotranspiration. While the timeframe for these changes (>10–20years) may be well in the realm of plant adaptation within breeding programs, there is a need for today’s breeding to understand the key mechanisms underlying crop phenology at a genotype level to better balance crop duration with available soil water and maximize light capture. This will then be used to re-fit phenology to new growing seasons under climate change conditions. The low water use efficiency, i.e., the amount of biomass or grain produced per unit of water used, under high vapor pressure deficit, although partly offset by an increased atmospheric CO2 concentration, would also require the search of germplasm capable of maintaining high water use efficiency under such conditions. Recent research has shown an interdependence of C and N nutrition in the N performance of legumes, a balance that may be altered under climate change. Ecophysiological models will be crucial in identifying genotypes adapted to these new growing conditions. An increased frequency of heat waves, which already happen today, will require the development of varieties capable of setting and filling seeds at high temperature. Finally, increases in temperature and CO2 will affect the geographical distribution of pests, diseases, and weeds, presenting new challenges to crop management and breeding programs.

Background Climate warming is a challenge for many plants and animals as they have to respond to rising temperature. Rising temperature was observed to affect herbivores and predators. Activity-density of abundant predatory carabid beetles, which are considered important natural control agents of agricultural pests, was observed to increase at rising temperature. The pollen beetle Meligethesaeneus is one of the most important insect pests in European oilseed rape fields, and its larvae were observed to be important prey to carabid beetles. Therefore, we performed a laboratory experiment to detect whether rising temperature affects the number of pollen beetle larvae killed by five abundant carabids, and larval biomass ingested by carabids. In three climate chambers actual temperature (T1) was compared to temperatures increased by 3 °C (T2) and 5 °C (T3). This is the first study investigating the feeding of carabid predators on an arable pest insect spanning a realistic forecasted climate warming scenario of 3 and 5 °C, thus providing basic knowledge on that neglected research area. We hypothesized that carabids kill more pollen beetle larvae at rising temperature, and biomass intake by carabids increases with rising temperature. Results Both beetle species and temperature had significant effects on the number of killed Meligethes larvae and larval biomass ingested by carabids. Amara ovata, Harpalus distinguendus and Poecilus cupreus killed significantly more pollen beetle larvae at T2 and T3 compared to T1. Anchomenus dorsalis killed significantly more larvae at T2 than T1, and Harpalus affinis showed no significant differences among temperatures. Biomass intake by A. ovata, H. distinguendus and A. dorsalis was significantly larger at T2 and T3 compared to T1. Biomass intake by H. affinis and P. cupreus did not significantly differ among temperatures. Among the five carabids tested P. cupreus exhibited the highest values for both number of killed larvae and biomass intake. Conclusions Our lab results suggest a clear potential for higher feeding of pollen beetle larvae by carabid beetles at rising temperature. As rising temperature leads to increased activity of abundant arable carabids in the field, it may be expected that there is enhanced pest suppression under warmer field conditions. Electronic supplementary material The online version of this article (doi:10.1186/s12898-016-0076-x) contains supplementary material, which is available to authorized users.