Littérature scientifique sur le sujet « Climate niche »
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Articles de revues sur le sujet "Climate niche"
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Bonetti, Maria Fernanda, et John J. Wiens. « Evolution of climatic niche specialization : a phylogenetic analysis in amphibians ». Proceedings of the Royal Society B : Biological Sciences 281, no 1795 (22 novembre 2014) : 20133229. http://dx.doi.org/10.1098/rspb.2013.3229.
Texte intégralRésumé :
The evolution of climatic niche specialization has important implications for many topics in ecology, evolution and conservation. The climatic niche reflects the set of temperature and precipitation conditions where a species can occur. Thus, specialization to a limited set of climatic conditions can be important for understanding patterns of biogeography, species richness, community structure, allopatric speciation, spread of invasive species and responses to climate change. Nevertheless, the factors that determine climatic niche width (level of specialization) remain poorly explored. Here, we test whether species that occur in more extreme climates are more highly specialized for those conditions, and whether there are trade-offs between niche widths on different climatic niche axes (e.g. do species that tolerate a broad range of temperatures tolerate only a limited range of precipitation regimes?). We test these hypotheses in amphibians, using phylogenetic comparative methods and global-scale datasets, including 2712 species with both climatic and phylogenetic data. Our results do not support either hypothesis. Rather than finding narrower niches in more extreme environments, niches tend to be narrower on one end of a climatic gradient but wider on the other. We also find that temperature and precipitation niche breadths are positively related, rather than showing trade-offs. Finally, our results suggest that most amphibian species occur in relatively warm and dry environments and have relatively narrow climatic niche widths on both of these axes. Thus, they may be especially imperilled by anthropogenic climate change.
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Varzinczak, Luiz H., Mauricio O. Moura et Fernando C. Passos. « Shifts to multiple optima underlie climatic niche evolution in New World phyllostomid bats ». Biological Journal of the Linnean Society 128, no 4 (22 octobre 2019) : 1008–20. http://dx.doi.org/10.1093/biolinnean/blz123.
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Abstract Climate underlies species distribution patterns, especially in species where climate limits distributions, such as the phyllostomid bats, which are mostly restricted to the New World tropics. The evolutionary dynamics that shaped phyllostomid climatic niches remain unclear, and a broad phylogenetic perspective is required to uncover their patterns. We used geographical distributions and evolutionary relationships of 130 species, climate data and phylogenetic comparative methods to uncover dynamics of phyllostomid climatic niche evolution. Diversification of climatic niches began early in phyllostomid evolution (~34 Mya), with most changes taking place ~20 Mya. Although most of these bats were found in tropical regions, shifts towards different evolutionary optima were common. Shifts were mostly towards temperate climates, reflecting complexities in phyllostomid evolution highlighted by the probable role of species-specific adaptations to cope with these climates, the influence of palaeoclimatic events, and biogeographical effects related to the evolution and dispersal of clades in the New World. Our results broaden our understanding of the relationships between phyllostomid bats and climate, filling an important gap in knowledge and suggesting a complex evolution in their occupation of the climatic niche space.
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Cang, F. Alice, Ashley A. Wilson et John J. Wiens. « Climate change is projected to outpace rates of niche change in grasses ». Biology Letters 12, no 9 (septembre 2016) : 20160368. http://dx.doi.org/10.1098/rsbl.2016.0368.
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Climate change may soon threaten much of global biodiversity, especially if species cannot adapt to changing climatic conditions quickly enough. A critical question is how quickly climatic niches change, and if this speed is sufficient to prevent extinction as climates warm. Here, we address this question in the grass family (Poaceae). Grasses are fundamental to one of Earth's most widespread biomes (grasslands), and provide roughly half of all calories consumed by humans (including wheat, rice, corn and sorghum). We estimate rates of climatic niche change in 236 species and compare these with rates of projected climate change by 2070. Our results show that projected climate change is consistently faster than rates of niche change in grasses, typically by more than 5000-fold for temperature-related variables. Although these results do not show directly what will happen under global warming, they have troubling implications for a major biome and for human food resources.
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Dorey, James B., Scott V. C. Groom, Elisha H. Freedman, Cale S. Matthews, Olivia K. Davies, Ella J. Deans, Celina Rebola, Mark I. Stevens, Michael S. Y. Lee et Michael P. Schwarz. « Radiation of tropical island bees and the role of phylogenetic niche conservatism as an important driver of biodiversity ». Proceedings of the Royal Society B : Biological Sciences 287, no 1925 (15 avril 2020) : 20200045. http://dx.doi.org/10.1098/rspb.2020.0045.
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Island biogeography explores how biodiversity in island ecosystems arises and is maintained. The topographical complexity of islands can drive speciation by providing a diversity of niches that promote adaptive radiation and speciation. However, recent studies have argued that phylogenetic niche conservatism, combined with topographical complexity and climate change, could also promote speciation if populations are episodically fragmented into climate refugia that enable allopatric speciation. Adaptive radiation and phylogenetic niche conservatism therefore both predict that topographical complexity should encourage speciation, but they differ strongly in their inferred mechanisms. Using genetic (mitochondrial DNA (mtDNA) and single-nucleotide polymorphism (SNP)) and morphological data, we show high species diversity (22 species) in an endemic clade of Fijian Homalictus bees, with most species restricted to highlands and frequently exhibiting narrow geographical ranges. Our results indicate that elevational niches have been conserved across most speciation events, contradicting expectations from an adaptive radiation model but concordant with phylogenetic niche conservatism. Climate cycles, topographical complexity, and niche conservatism could interact to shape island biodiversity. We argue that phylogenetic niche conservatism is an important driver of tropical island bee biodiversity but that this phylogenetic inertia also leads to major extinction risks for tropical ectotherms under future warming climates.
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Duarte, Milen, Pablo C. Guerrero, Mary T. K. Arroyo et Ramiro O. Bustamante. « Niches and climate-change refugia in hundreds of species from one of the most arid places on Earth ». PeerJ 7 (12 septembre 2019) : e7409. http://dx.doi.org/10.7717/peerj.7409.
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Background and Aims Global climate change is a major threat to biodiversity worldwide. Several arid areas might expand in the future, but it is not clear if this change would be positive or negative for arid-adapted lineages. Here, we explore whether climatic niche properties are involved in the configuration of climate refugia and thus in future species trends. Methods To estimate putative climate refugia and potential expansion areas, we used maximum entropy models and four climate-change models to generate current and future potential distributions of 142 plant species endemic to the Atacama and mediterranean Chilean ecosystems. We assessed the relationship between the similarity and breadth of thermal and precipitation niches with the size of climate refugia and areas of potential expansions. Key Results We found a positive relationship between breadth and similarity for thermal niche with the size of climate refugia, but only niche similarity of the thermal niche was positively related with the size of expansion areas. Although all lineages would reduce their distributions in the future, few species are predicted to be at risk of extinction in their current distribution, and all of them presented potential expansion areas. Conclusion Species with a broad niche and niche dissimilarity will have larger refugia, and species with niche dissimilarity will have larger expansion areas. In addition, our prediction for arid lineages shows that these species will be moderately affected by climate change.
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Vásquez-Aguilar, Antonio Acini, Juan Francisco Ornelas, Flor Rodríguez-Gómez et M. Cristina MacSwiney G. « Modeling Future Potential Distribution of Buff-Bellied Hummingbird (Amazilia yucatanensis) Under Climate Change : Species vs. Subspecies ». Tropical Conservation Science 25 (janvier 2021) : 194008292110308. http://dx.doi.org/10.1177/19400829211030834.
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Global climate change is associated with changes in precipitation patterns and an increase in extreme weather events, which might shift the geographic distribution of species. Despite the importance of this topic, information is lacking for many species, particularly tropical birds. Here, we developed species distribution models (SDMs) to evaluate future projections of the distribution of the widespread Buff-bellied Hummingbird ( Amazilia yucatanensis) and for each of the recognized subspecies ( A. y. yucatanensis, A. y. cerviniventris, A. y. chalconota), under climate change scenarios. Using SDMs we evaluate current and future projections of their potential distribution for four Representative Concentration Pathway (RCPs) for the years 2050 and 2070. We also calculated the subspecies climatic niche breadth to test the relationship between their area of distribution and climatic niche breadth and their niche overlap. Future climate-change models suggested a small increase in the potential distribution of the species and the subspecies A. y. yucatanensis, but the predicted potential geographic range decreased in A. y. chalconota and remained unaffected in A. y. cerviniventris. The climatic niche of A. y. cerviniventris contained part niche space of A. y. yucatanensis and part of A. y. chalconota, but the climatic niches of A. y. yucatanensis and A. y. chalconota did not overlap. Our study highlights the importance of correctly choosing the taxonomic unit to be analyzed because subspecies will respond in a different manner to future climate change; therefore, conservation actions must consider intrinsic requirements of subspecies and the environmental drivers that shape their distributions.
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Grossman, Jake J. « Evidence of Constrained Divergence and Conservatism in Climatic Niches of the Temperate Maples (Acer L.) ». Forests 12, no 5 (26 avril 2021) : 535. http://dx.doi.org/10.3390/f12050535.
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Research highlights: The availability of global distribution data and new, fossil-calibrated phylogenies has made it possible to compare the climatic niches of the temperate maple (Acer L.) taxa and assess phylogenetic and continental patterns in niche overlap. Background and Objectives: The maples have radiated from East Asia into two other temperate continental bioregions, North America and Eurasia (Europe and West Asia), over a roughly 60-million-year period. During this time, the Earth’s climate experienced pronounced cooling and drying, culminating in cyclic periods of widespread temperate glaciation in the Pliocene to Pleistocene. The objective of this study is to use newly available data to model the climatic niches of 60% of the temperate maples and assess patterns of niche divergence, constraint, and conservatism in the genus’s radiation out of East Asia. Materials and Methods: I assembled global occurrence data and associated climatic information for 71 maple taxa, including all species endemic to temperate North America and Eurasia and their closely related East Asian congeners. I constructed Maxent niche models for all taxa and compared the climatic niches of 184 taxa pairs and assessed phylogenetic signal in key niche axes for each taxon and in niche overlap at the continental and global scale. Results: Maxent models define a fundamental climatic niche for temperate maples and suggest that drought-intolerant taxa have been lost from the Eurasian maple flora, with little continental difference in temperature optima or breadth. Niche axes and niche overlap show minimal evidence of phylogenetic signal, suggesting adaptive evolution. Pairwise niche comparisons reveal infrequent niche overlap continentally and globally, even among sister pairs, with few taxa pairs sharing ecological niche space, providing evidence for constrained divergence within the genus’s fundamental climatic niche. Evidence of niche conservatism is limited to three somewhat geographically isolated regions of high maple diversity (western North America, the Caucasus, and Japan). Conclusions: Over 60 million years of hemispheric radiation on a cooling and drying planet, the maple genus experienced divergent, though constrained, climatic niche evolution. High climatic niche diversity across spatial and phylogenetic scales along with very limited niche overlap or conservatism suggests that the radiation of the genus has largely been one of adaptive diversification.
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Qu, Yan-Fu, et John J. Wiens. « Higher temperatures lower rates of physiological and niche evolution ». Proceedings of the Royal Society B : Biological Sciences 287, no 1931 (15 juillet 2020) : 20200823. http://dx.doi.org/10.1098/rspb.2020.0823.
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Understanding rates and patterns of change in physiological and climatic-niche variables is of urgent importance as many species are increasingly threatened by rising global temperatures. Here, we broadly test several fundamental hypotheses about physiological and niche evolution for the first time (with appropriate phylogenetic methods), using published data from 2059 vertebrate species. Our main results show that: (i) physiological tolerances to heat evolve more slowly than those to cold, (ii) the hottest climatic-niche temperatures change more slowly than the coldest climatic-niche temperatures, and (iii) physiological tolerances to heat and cold evolve more slowly than the corresponding climatic-niche variables. Physiological tolerances are significantly and positively related to the corresponding climatic-niche variables, but species often occur in climates outside the range of these tolerances. However, mismatches between climate and physiology do not necessarily mean that the climatic-niche data are misleading. Instead, some standard physiological variables used in vertebrates (i.e. critical thermal maxima and minima) may reflect when species are active (daily, seasonally) and their local-scale microhabitats (sun versus shade), rather than their large-scale climatic distributions.
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Amano, Tatsuya, Robert P. Freckleton, Simon A. Queenborough, Simon W. Doxford, Richard J. Smithers, Tim H. Sparks et William J. Sutherland. « Links between plant species’ spatial and temporal responses to a warming climate ». Proceedings of the Royal Society B : Biological Sciences 281, no 1779 (22 mars 2014) : 20133017. http://dx.doi.org/10.1098/rspb.2013.3017.
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To generate realistic projections of species’ responses to climate change, we need to understand the factors that limit their ability to respond. Although climatic niche conservatism, the maintenance of a species’s climatic niche over time, is a critical assumption in niche-based species distribution models, little is known about how universal it is and how it operates. In particular, few studies have tested the role of climatic niche conservatism via phenological changes in explaining the reported wide variance in the extent of range shifts among species. Using historical records of the phenology and spatial distribution of British plants under a warming climate, we revealed that: (i) perennial species, as well as those with weaker or lagged phenological responses to temperature, experienced a greater increase in temperature during flowering (i.e. failed to maintain climatic niche via phenological changes); (ii) species that failed to maintain climatic niche via phenological changes showed greater northward range shifts; and (iii) there was a complementary relationship between the levels of climatic niche conservatism via phenological changes and range shifts. These results indicate that even species with high climatic niche conservatism might not show range shifts as instead they track warming temperatures during flowering by advancing their phenology.
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Waterson, Amy M., Daniela N. Schmidt, Paul J. Valdes, Patricia A. Holroyd, David B. Nicholson, Alexander Farnsworth et Paul M. Barrett. « Modelling the climatic niche of turtles : a deep-time perspective ». Proceedings of the Royal Society B : Biological Sciences 283, no 1839 (28 septembre 2016) : 20161408. http://dx.doi.org/10.1098/rspb.2016.1408.
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Ectotherms have close physiological ties with the thermal environment; consequently, the impact of future climate change on their biogeographic distributions is of major interest. Here, we use the modern and deep-time fossil record of testudines (turtles, tortoises, and terrapins) to provide the first test of climate on the niche limits of both extant and extinct (Late Cretaceous, Maastrichtian) taxa. Ecological niche models are used to assess niche overlap in model projections for key testudine ecotypes and families. An ordination framework is applied to quantify metrics of niche change (stability, expansion, and unfilling) between the Maastrichtian and present day. Results indicate that niche stability over evolutionary timescales varies between testudine clades. Groups that originated in the Early Cretaceous show climatic niche stability, whereas those diversifying towards the end of the Cretaceous display larger niche expansion towards the modern. Temperature is the dominant driver of modern and past distributions, whereas precipitation is important for freshwater turtle ranges. Our findings demonstrate that testudines were able to occupy warmer climates than present day in the geological record. However, the projected rate and magnitude of future environmental change, in concert with other conservation threats, presents challenges for acclimation or adaptation.
Thèses sur le sujet "Climate niche"
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Bublys, Kasparas. « Diet variability in Eurasian perch (Perca fluviatilis) as a response to environmental variables along a latitudinal gradient ». Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-365794.
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Climate change is expected to have a profound impact on freshwater fish communities, especially at higher latitudes. In this study I investigated potential effects of climate change on the niche structure of Eurasian perch (Perca fluviatilis) by looking at their diet across a latitudinal gradient and at varying light climate. Dietary niche width of Eurasian perch did not differ significantly between boreal and temperate latitudes. Additionally, no significant difference in the prevalence of specialist individuals was found along the latitudinal gradient and water transparency levels. Habitat was the main factor that significantly affected niche width and level of specialization with both being significantly higher in the littoral habitat. Taken together my results suggest that climate change might indirectly affect niche patterns by altering fish densities through changes in productivity resulting in niche and specialization variation among habitats.
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Bledsoe, April, Danika Mosher, Mitchell Ogden, Monica Ayala, Timothy Andrew Joyner et Ingrid Luffman. « Ecological Niche Modeling and Sustainable Agroforestry : Climate Change Mitigation for Guatemalan Coffee ». Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/70.
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Coffea arabica is a species with far-reaching impacts on the global economy. Nevertheless, climate-related challenges threaten the coffee industry at its source: its growing regions. The coffee industry is a significant economic driver in Guatemala, but farmers are increasingly reporting losses in crop yield and arable land due to climate-related challenges. Ecological niche modeling (ENM) can be employed to make predictions about the current and future suitability of regions for a species by identifying significant biotic or abiotic indicators. An ENM was used to project suitable land into the future using climate change projection models known as representative concentration pathways (RCPs), for the coffee plant and a number of other species. Due to the potential of shade trees to lessen heat stress on coffee plants, common shade trees for the region were modeled. Additionally, a fungus species responsible for detrimental coffee leaf rust was modeled. Results of these models indicated potential for substantial climate-related habitat losses for the coffee plant in the coming decades. Examination of model predictions allow for greater understanding of the climate-related variables affecting the ecology of the coffee plant, and the potential risks to the industry, in a changing climate. Additionally, ENM models for coffee rust and shade trees can help Guatemalan farmers make informed decisions about farm management.
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Bledsoe, April, Danika Mosher, Mitchell Ogden, Monica Ayala, T. Andrew Joyner Joyner et Ingrid Luffman. « Ecological Niche Modeling and Sustainable Agroforestry : Climate Change Mitigation for Guatemalan Coffee ». Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/64.
Texte intégralRésumé :
Coffea arabica is a species with far-reaching impacts on the global economy. Nevertheless, climate-related challenges threaten the coffee industry at its source: its growing regions. The coffee industry is a significant economic driver in Guatemala, but farmers are increasingly reporting losses in crop yield and arable land due to climate-related challenges. Ecological niche modeling (ENM) can be employed to make predictions about the current and future suitability of regions for a species by identifying significant biotic or abiotic indicators. An ENM was used to project suitable land into the future using climate change projection models known as representative concentration pathways (RCPs), for the coffee plant and a number of other species. Due to the potential of shade trees to lessen heat stress on coffee plants, common shade trees for the region were modeled. Additionally, a fungus species responsible for detrimental coffee leaf rust was modeled. Results of these models indicated potential for substantial climate-related habitat losses for the coffee plant in the coming decades. Examination of model predictions allow for greater understanding of the climate-related variables affecting the ecology of the coffee plant, and the potential risks to the industry, in a changing climate. Additionally, ENM models for coffee rust and shade trees can help Guatemalan farmers make informed decisions about farm management.
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Boucher, Florian. « Evolution de la niche climatique et de la distribution géographique des espèces végétales alpines ». Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01062257.
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La niche climatique des espèces joue un rôle important dans la distribution spatiale de la biodiversité mais la manière dont les niches climatiques évoluent reste encore peu connue. Ce travail vise à révéler la manière dont les niches climatiques évoluent en général, et plus précisément à déterminer comment certaines plantes se sont adaptées aux environnements alpins. En étudiant de nombreux groupes de plantes, de poissons, de mammifères et d'oiseaux, nous avons montré que les niches climatiques évoluent le plus souvent par à-coups et non pas de manière graduelle. Les niches climatiques restent en effet stables pendant des périodes de plusieurs millions d'années puis évoluent de manière extrêmement rapide avant de se stabiliser à nouveau dans une autre gamme de climat. Des simulations ont permis de montrer que les phases de relative stabilité n'étaient pas forcément causées par une sélection stabilisante sur les niches climatiques mais pouvaient également résulter de la présence de barrières géographiques qui empêchent les espèces d'expérimenter de nouveaux climats. L'étude de l'histoire des plantes du genre Androsace a révélé que les changements rapides de niches correspondaient au contraire à l'apparition de nouveaux traits, comme la forme de vie en coussin. Ce travail montre que de nombreux facteurs influencent l'évolution des niches climatiques et souligne la nécessité de tous les étudier ensemble.
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Audusseau, Hélène. « Effect of climate and land use on niche utilization and distribution of nettle-feeding butterflies ». Doctoral thesis, Stockholms universitet, Zoologiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-119719.
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Anthropogenic changes in climate and land use are causing a dramatic erosion of biodiversity. To understand this erosion, and predict future transformations of biodiversity, we need to understand better species’ response to these changes at different spatial and temporal scales. Modeling studies have identified correlations between physical parameters of the environment and species’ distribution at large spatial scales. However, this does not accurately characterize the response of a specific species, since this does not account for the constraints arising from the biology of the species. This thesis shall combine knowledge on the biology of species obtained from laboratory experiments with modeling studies. This will allow us (i) to identify life history traits and biotic interactions that influence species’ adaptive potential, and hence, explain possible differences in species’ distribution, and (ii) to consider, not only the ecological but also the evolutionary aspects of species’ response to changes. This integrative approach is likely to improve our predictions on species’ population dynamic in a changing environment. I focus on a community of butterflies in Sweden (Vanessa cardui, Polygonia c-album, Aglais urticae, Aglais io, Araschnia levana) that feeds on the stinging nettle (Urtica dioica). The available knowledge on the biology of these species and their short life cycles, which allow investigations of their response to changes on a short-time scale, make them a good system to study. Among three of these species, I showed great differences in organisms’ response to variation in food nutrient content. This is a potentially important finding considering the increased use of chemical fertilizers. These differences are to a large extent explained by differences among species in their degree of host plant specialization and voltinism (paper II). Thus, life history traits determine the response of species to environmental changes, but are themselves likely to evolve in response to such changes. Climate change, for instance, may alter the phenological synchrony between plant-feeding insects and their host plants, making it necessary for the insects to evolve their host plant range in order to ensure the availability of resources during larval development (paper I & III). The biology of a species, including biotic interactions, helps to explain the observed shift in a species’ distribution and environmental niche that result from climate change. I have shown that the recent establishment of A. levana in southern Sweden has modified the niche of the resident species, A. urticae and A. io (Paper IV). Niche partitioning in this community is likely mediated by parasite-driven apparent competition.Mänsklig påverkan på klimat och markanvändning har orsakat en dramatisk förlust av biologisk mångfald. Effekten av dessa förändringar på lokal och regional nivå är dock komplex, och kräver integrativa strategier för att kunna förstå och förutsäga förändringar, på individ-, art- och samhällsnivå. Experimentella studier har utforskat arters plastiska och evolutionära respons till främst abiotiska förändringar, och observationsdata har använts för att modellera skiften i fenologi och utbredning som en konsekvens av klimatförändringar. Trots detta är det fortfarande mycket kvar att förstå för att kunna förutsäga hur miljöförändringar ska påverka arters respons på olika rumsliga och tidsliga skalor. Denna avhandling undersöker i vilken utsträckning arters specifika livshistoria och artinteraktioner kan förklara deras ekologiska och evolutionära respons på miljöförändringar. För att angripa detta har jag fokuserat på ett samhälle av fjärilar i Sverige (Vanessa cardui, Polygonia c-album, Aglais urticae, Aglais io, Araschnia levana) som alla lever på brännässla (Urtica dioica). Den tillgängliga kunskapen om dessa arters biologi samt deras korta livscykler gör det möjligt att undersöka deras svar på förändringar över korta tidsskalor, vilket gör dem till ett lämpligt studiesystem. Huvudslutsatsen från denna avhandling är att för att beskriva hur en art svarar på en förändring måste man ta hänsyn till variation i livshistorieegenskaper och artinteraktioner. Till exempel har den ökade användningen av kemiska gödningsmedel förändrat näringstillgången även i naturliga ekosystem, vilket gynnar växtarter som är kapabla att växa under höga näringsnivåer, som brännässla. Variation i växternas näringsinnehåll kommer i sin tur att påverka herbivorerna som äter av dem, och artikel II visar att skillnader mellan fjärilsarter i hur de svarar på variation i näringstillgång till stor del beror på specialiseringsgrad och voltinism (antal generationer per år). Livshistorieegenskaper avgör således hur arter kommer att svara på förändringar i klimat och markanvändning, men sådana miljöförändringar påverkar i sin tur också evolution av livshistorieegenskaperna (artikel I & III). Slutligen, förändringar i utbredning som ett resultat av klimatförändring kommer även att påverka den lokala sammansättningen av interagerande arter (resurser, predatorer, konkurrenter). Ett exempel på detta är hur den relativt nyliga koloniseringen av södra Sverige av A. levana har förändrat nischerna hos de inhemska arterna A. urticae och A. io (artikel IV).
Le réchauffement climatique et les changements d’occupation des terres d'origine anthropique provoquent une forte érosion de la biodiversité. Pour comprendre cette érosion, et prédire les transformations futures de la biodiversité, il nous faut mieux connaitre la réponse des espèces à ces changements, aux différentes échelles spatiales et temporelles. Grâce à des outils de modélisation statistique, des corrélations entre les paramètres physiques de l’environnement et la distribution des espèces à grande échelle spatiale ont été observées. Mais ceci ne suffit pas à caractériser finement la réponse d’une espèce donnée, car celle-ci dépend des caractéristiques biologiques propres de l’espèce. Cette thèse se propose donc d’associer les connaissances sur la biologie des espèces obtenues par des expériences en laboratoire à des études de modélisation. Ceci permettra (i) d’identifier des traits d’histoire de vie et les relations biotiques qui influencent le potentiel adaptatif des espèces, et donc expliquent d’éventuelles différences de répartition, et (ii) d’envisager, au-delà des aspects écologiques, la composante évolutive de cette réponse. Une telle approche intégrative est susceptible d’améliorer nos prédictions sur la dynamique des espèces dans un environnement changeant. Le système d’étude de cette thèse est une communauté de papillons en Suède (Vanessa cardui, Polygonia c-album, Aglais urticae, Aglais io, Araschnia levana), se nourrissant de l'ortie (Urtica dioica). La biologie de ces espèces est bien connue et leur cycle de vie rapide permet d’étudier leur réponse aux changements à une échelle de temps court. Chez trois de ces espèces, j’ai mis en évidence des réponses très différentes à une augmentation de la teneur en nutriments de leur nourriture, conséquence attendue de l’utilisation accrue d’engrais chimiques. Ces différences sont dans une large mesure expliquée par la gamme de plantes hôtes utilisées et le voltinisme (article II). Ces traits d'histoire de vie déterminent donc la réponse des espèces aux changements, mais sont eux-mêmes susceptibles d’évoluer. Par exemple, le réchauffement climatique modifie la synchronie entre les insectes herbivores et leurs plantes hôtes et pousse à l’évolution du régime alimentaire des papillons afin que la présence de ressources soit assurée durant le développement des larves (articles I & III). Les connaissances sur la biologie des espèces, y compris leurs interactions biotiques, permettent de comprendre les variations de leur distribution spatiale et de leur niche environnementale. Ainsi, l’établissement récent d’A. levana dans le sud de la Suède, suite au réchauffement, a modifié les niches des espèces résidentes, A. urticae et A. io (article IV).
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 4: Manuscript.
Ekoklim
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Serra, Díaz Josep M. « Applying correlative ecological niche models to global change studies ». Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/96302.
Texte intégralRésumé :
La distribució de les espècies ha estat objecte d’estudi per part de diverses disciplines donada la seva naturalesa multifactorial. Així, entendre veritablement la distribució de les espècies implica necessàriament un millor coneixement del funcionament de la biosfera. D’altra banda, el canvi global que està patint el nostre planeta previsiblement afectarà en gran mesura moltes espècies, variant així la distribució i composició dels ecosistemes tal i com els coneixem avui dia i implícitament dels serveis que proporcionen.
La modelització ha permès augmentar el nostre grau de comprensió sobre el sistema Terra així com de les potencials conseqüències que els canvis antropogènics poden provocar (canvi climàtic, alteració de cicles biogeoquímics, destrucció d’hàbitats, etc.). En el camp de la distribució d’espècies, els models de nínxol ecològic han estat àmpliament utilitzats per estudiar i preveure canvis en la distribució dels organismes. Aquests models es basen en la determinació de les condicions ambientals òptimes on una determinada espècie pot viure i reproduir-se (nínxol).
Tanmateix, aquests models fan ús d’aproximacions correlatives entre presències i variables ambientals actuals, fet que presenta diverses desavantatges que posen de manifest una gran incertesa en les prediccions i fins i tot, qüestionen la seva utilitat en el context de canvi global. El conjunt dels treballs que s’exposen pretenen donar una visió sintètica de la possibilitat d’ús d’aquests models per a prediccions de distribució d’espècies vegetals, tant presents com futures.
La present recerca se centra en l’anàlisi de diversos aspectes problemàtics per a aquests models en la predicció de la distribució´ d’espècies vegetals en el context del canvi global. Específicament s’ha avaluat la diferència entre prediccions basades en models ecofisiològics i models correlatius sobre l’efecte de prediccions actuals i futures , la variació entre prediccions a nivell de taxó o a nivell de comunitat, la variació en la predicció de canvi de nínxol davant possibles invasions i finalment, l’addició de l’escala temporal en les prediccions.
S’ha pogut constatar que el fet de basar-se en correlacions estàtiques minva la seva capacitat de transferència a noves situacions i no incorpora trets biològics que poden tenir una importància cabdal (p.ex. fisiologia). En situacions de projeccions en l’espai i en el temps, s’observen importants variacions espacials en les prediccions, tant a nivell de comunitat com a nivell de poblacions de diversa provinença. Això comporta que les assumpcions i l’escala geogràfica i biològica hagin de ser adaptades segons la qüestió a la que el model s’adreça així com de la disponibilitat de dades. A més, incorporar l’escala temporal pot afegir una cert grau de dinamisme a aquests models estàtics, malgrat que no es poden inferir efectes a una resolució temporal adequada per a alguns fenòmens climàtics extrems .
Dels resultats se’n desprèn que la utilització d’aquests models pot servir com a una bona eina de generació d’hipòtesis sobre dels diferents factors que actualment constrenyen la distribució de les espècies. A més, pot ser una tècnica potent per estimar el grau d’exposició de les espècies davant noves situacions de canvi global. Tot i això, les seves prediccions han de ser confrontades amb d’altres tècniques oimés quan es tracta de valorar escenaris plausibles subjectes a una gran incertesa. En general, aquests models són molt significatius per a la caracterització de l’exposició a noves situacions.La distribución de las especies ha sido objetos de estudio por parte de diversas disciplinas dada su naturaleza multifactorial. Así, entender verdaderamente la distribución de las especies implica necesariamente un mejor conocimiento del funcionamiento de la biosfera. Por otro lado, el cambio global que esta sufriendo nuestro planeta previsiblemente afectará en gran medida muchas especies, variando su distribución y en última instancia, la composición de los ecosistemas tal y como los conocemos hoy día así como los servicios que proporcionan. La modelización ha permitido aumentar nuestro grado de comprensión sobre el sistema Tierra así como de las potenciales consecuencias que los cambios antropogénicos pueden provocar (cambio climático, alteración de ciclos biogeoquímicos, destrucción de hábitats, etc.). En el campo de la distribución de especies, los modelos de nicho ecológico han sido ampliamente utilizados para estudiar y predecir cambios en la distribución de los organismos. Estos modelos se basan en la determinación de las condiciones ambientales óptimas en las que una determinada especie puede vivir y reproducirse (nicho). Sin embargo, estos modelos utilizan una aproximación correlativa entre presencia de un organismo y las variables ambientales actuales, hecho que presenta diversas desventajas que ponen de manifiesto una gran incertidumbre en las predicciones e incluso, cuestionan su utilidad en el contexto del cambio global. El conjunto de los trabajos que aquí se exponen pretenden dar una visión sintética de la posibilidad de uso de estos modelos para predicciones de la distribución de especies vegetales, tanto presentes como futuras. La presente investigación se centra en el análisis de aspectos problemáticos de índole diversa de este tipo de modelos, cuando son aplicados para predecir la distribución de especies vegetales bajo supuestos de cambio global. Específicamente se ha evaluado la diferencia entre predicciones basadas en modelos ecofisiológicos y modelos correlativos en la predicción de distribuciones presentes y futuras, la variación entre predicciones a nivel de taxón o a niveles de comunidad, la variación en la predicción según la población bajo riesgos potenciales de cambio de nicho i finalmente, la adición de la escala temporal en las predicciones. Se ha podido constatar que el hecho de basarse en correlaciones estáticas disminuye su capacidad de transferencia a nuevas situaciones i no incorpora características biológicas que pueden tener una importancia vital (p.ej. fisiología). En situaciones de proyecciones en el espacio y el tiempo, se observan variaciones espaciales significativas en las predicciones, tanto a nivel de comunidad como a nivel de poblaciones de diverso origen. Esto comporta que las asunción i la correcta elección de la escala geográfica i biológica según el objetivo del modelo. Además, la incorporación de la escala temporal puede añadir un cierto grado de dinamismo a estos modelos estáticos, a pesar que no se pueden inferir efectos a una resolución temporal adecuada para algunos fenómenos climáticos extremos. En general, dichos modelos son relevantes para caracterizar la exposición a nuevas situaciones.
The distribution of species has been studied by various disciplines due to its multifactorial nature. Thus, to truly understand the distribution of species necessarily implies a better understanding of the functioning of the biosphere. On the other hand, the overall change our planet is undergoing, it is expected to greatly affect many species, varying distribution and ultimately the composition of ecosystems as we know them today and the services they provide. The modeling has enhanced our level of understanding of the Earth system and the potential consequences that anthropogenic changes can cause (climate change, alteration of biogeochemical cycles, habitat destruction, etc..). In the field of species distribution, ecological niche models have been widely used to study and predict changes in the distribution of organisms. These models are based on determining the optimum environmental conditions in which a species can live and reproduce (niche). However, these models use a correlative approach between the presence of an organism and the current environmental variables, which has several disadvantages that cause a uncertainty in predictions and even question their usefulness in the context of global change. All the works presented here are intended to give a synthetic view of the possibility of using these models for predictions of the distribution of plant species, both present and future. This research focuses on the analysis of problematic aspects of these models, when applied to predict the distribution of plant species under global change scenarios. Specifically we evaluated the difference between model predictions and ecophysiological models to predict correlative and future distributions, the variation between predictions at the level of taxon or community levels, the variation in the prediction at the population levels and finally, the addition of the timescale in the predictions. It has been shown that basing predictions on static correlations diminishes their transference capacity to new situations and does not incorporate key biological traits that may play a key role (e.g. physiology). In projections in space and time, it has been observed significant spatial variations in predictions, whether at the community or individual level of species or different populations across continents. This implies that the choice of the biological or geographical scale may be fit for model’s purpose. Furthermore, the incorporation of the temporal scale may add a certain degree of dynamism to these static modles, despite they cannot be infered for effects at higher temporal resolution for some extreme climatic events. In general, such models are relevant to characterize exposure to new situations.
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Vázquez, Rivera Héctor. « Changing Climate and Geographical Patterns of Taxonomic Richness ». Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31721.
Texte intégralRésumé :
The geographic variation of taxonomic richness may be directly determined by climate through contemporaneous/ecological processes, versus other (e.g., historical/evolutionary processes) that happen to be collinear with contemporaneous climate. In Chapter 1 I evaluated hypotheses from both groups of explanations in North America. If contemporaneous climate controls patterns of richness, then richness should vary with climate through time in the same way that richness varies with current climate through space. Over the last ca. 11,000 yr, richness-temperature relationships remained reasonably constant. Between 12,000 and 14,000 yr BP, when climate fluctuated rapidly, richness gradients as a function of temperature were significantly shallower. If historical climate over the last 21,000 years determines patterns of richness, then historical climate should be a better predictor of richness than contemporaneous climate. I rejected historical-climate as a better predictor of richness. Contemporaneous climate stands as the most plausible explanation for contemporaneous patterns of richness, at least over the last 11,000 yr. In Chapter two, I tested the prediction that richness of most taxa should increase with temperature in all but the warmest and driest areas. Climate warming during Pleistocene-Holocene transition led richness increases in wet areas, but richness declines in dry regions, as expected from current richness-climate relationships. A decline in small mammal species richness in Northern California since the late Pleistocene was expected from the current richness-climate relationship for this group in North America. These results contest the view that future global warming may lead to species extinction rates that would qualify as the sixth mass extinction in the history of the earth. In chapter three, I first tested the hypothesis that richness gradients mainly reflect the sum of individual species climatic tolerances. I tested this hypothesis for birds, mammals and trees native to eastern North America (ENA, where there are no major barriers to dispersal). The number of species present in any given area in ENA is usually much smaller than the number of species in the continental pool that tolerate the climatic conditions in that area. Second, I tested several explanations for patterns of unfilled potential richness. Unfilled potential richness is inconsistent with postglacial dispersal lags, climatic variability since the Last Glacial Maximum, or with biotic interactions. In contrast, unfilled richness is highly consistent with a probabilistic model of species climate occupancy. Individual species climatic tolerances is not the process generating the main current patterns of richness, nor are post-glacial dispersal lags, climatic variability since the LGM or biotic interactions. This thesis is consistent with the hypothesis that contemporaneous climate directly controls spatial patterns of richness. Generally, there seems to be little need to invoke historical processes as determinants of current gradients of richness.
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Boavida-Portugal, Joana Sousa e. Silva. « Global patterns of marine biodiversity and the potential impact of climate change ». Doctoral thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/27840.
Texte intégralRésumé :
Marine species are highly susceptible to climate change as demonstrated by several
studies. However, most of these studies focus on few species or on restricted
geographical areas. Within this context, the main goal of my dissertation is to
characterize global patterns and forecast the effects of climate change on marine
biodiversity. This work is the first macroecological approach to investigate the effects of
climate change in the marine realm on key commercial marine groups, namely coastal
lobsters (125 species), cephalopods (161 species) and small pelagic fish (103 species).
Here I aimed to improve our understanding of how projected changes in species
distribution might affect key marine species diversity, body size, assemblage
composition, variations in catch, and finally infer on the potential impacts for fisheries
worldwide. Using Ecological Niche Models (ENMs) the projected global diversity
patterns of the analyzed species generally showed higher values in tropical areas and
lower values in higher latitudes. Nonetheless, these patterns were projected to change
significantly by the end of the century, with a general tendency of species tracking
adequate habitat suitability to higher latitudes. The results obtained provide critical
information to anticipate negative impacts of climate change on marine biodiversity and
should be considered in future studies, as they highlight climate hot-spot areas or with
highly vulnerable species. Ultimately, it is crucial to evaluate species adaptation
potential and develop hybrid models that better can guide future political decisions on
conservation and management measures; RESUMO:
Padrões globais da biodiversidade marinha e o potencial impacto das alterações
climáticas
As espécies marinhas são altamente suscetíveis às alterações climáticas, como
demonstrado em numerosos estudos. Porém muitos desses estudos focam-se num
número reduzido de espécies ou numa determinada área geográfica (local ou regional).
Neste contexto, a presente dissertação tem como objetivo investigar os padrões globais
de biodiversidade marinha e projetar como estes poderão estar modificados no final do
século. Este trabalho constitui a primeira abordagem macroecológica que investiga,
numa escala global, os impactos das alterações climáticas em taxa marinhos com alto
interesse económico, como lagostas (125 espécies), cefalópodes (161 espécies) e
pequenos peixes pelágicos (103 espécies). Os padrões globais de biodiversidade
marinha para todos os taxa analisados mostram maior riqueza na zona dos trópicos e
menor número de espécies nas maiores latitudes. No entanto, estes padrões podem
sofrer modificações significativas até ao final do século verificando-se uma tendência
generalizada das espécies migrarem para latitudes maiores de forma a encontrarem
refúgio em áreas com boa adequação ambiental. Os modelos usados nesta tese
(modelos de nicho ecológico) projetam alterações significativas na distribuição das
espécies analisadas, com impactos profundos na riqueza e abundância em áreas vitais
para a saúde dos oceanos e para as pescas, a longo prazo. Esta dissertação representa
um contributo importante para o conhecimento dos padrões globais da biodiversidade
nos oceanos futuros. Servindo os seus resultados para orientar estudos pormenorizados
em áreas de risco elevado ou com espécies mais vulneráveis e informar a tomada de
decisões com vista a proteção de espécies marinhas com elevado valor económico e
ambiental. Contudo, atendendo aos efeitos das alterações climáticas já sentidos nos
oceanos, é crucial avaliar a capacidade de adaptação destas espécies e encontrar
modelos híbridos que melhor nos permitam orientar medidas de gestão e conservação
futuras.
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Compagnoni, Aldo. « Climate change and plant demography in the sagebrush steppe ». DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1748.
Texte intégralRésumé :
We used demographic methods to address one of the main challenges facing ecological science: forecasting the effect of climate change on plant communities. Ecological forecasts will be crucial to inform long-term planning in wildland management and demographic methods are ideal to quantify changes in plant abundance. We carried out our research in the sagebrush steppe, one of the most extensive plant ecosystems of Western North America. Our research intended to inform ecological forecasts on an exotic invader, cheatgrass (Bromus tectorum). Moreover, we investigated the general question asking: to what degree competition among plants influences the outcome of ecological forecasts on the effect of climate change? We carried out two field experiments to test the hypothesis that warming will increase cheatgrass abundance in the sagebrush steppe. This hypothesis was strongly supported by both experiments. Warming increased cheatgrass abundance regardless of elevation, neighboring vegetation or cheatgrass genotype. Moreover, we found cheatgrass was hindered by snow cover. Therefore, warming increases cheatgrass growth directly by increasing temperature, and indirectly by decreasing or removing snow cover. In our last experiment, we tested whether forecasts of climate change effects on rare species can ignore competition from neighbors. This should occur because rare species should have little niche overlap with other species. The lower the niche overlap, the less competition with other species. To test this hypothesis, we used a long-term data set from an Idaho sagebrush steppe. We built population models that reproduced the dynamics of the system by simulating climate and competition. Model simulations supported our hypothesis: rare species have little niche overlap and little competitive interactions with neighbor species.
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Yadav, Sunita. « The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges : A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae) ». University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690823.
Texte intégralLivres sur le sujet "Climate niche"
1
Tatōiki Fōramu Kokusai Shinpojūmu (2006 Kagoshima Daigaku Tatōken Kenkyū Sentā). Chikyū ondanka to Taiheiyō tōsho chiiki : Tatōiki Fōramu Kokusai Shinpojūmu hōkoku : 2006-nen 2-gatsu 4-nichi. Kagoshima-shi : Kagoshima Daigaku Tatōken Kenkyū Sentā, 2007.
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Turned out nice : How the British Isles will change as the world heats up. London : Faber and Faber, 2010.
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3
Newman, Chris, Christina D. Buesching et David W. Macdonald. Meline mastery of meteorological mayhem : the effects of climate changeability on European badger population dynamics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198759805.003.0021.
Texte intégralRésumé :
Adaptation to climatic conditions is a major ecological and evolutionary driver. Long-term study of European badger population dynamics in Oxfordshire reveals that rainfall and temperature patterns affect food (principally earthworm) availability, energy expended in thermoregulation, and activity patterns, with badgers able to seek refuge in their setts. Cubs prove especially vulnerable to harsh weather conditions, where drought and food shortages exacerbate the severity of pandemic juvenile coccidial parasite infections. Crucially, weather variability, rather than just warming trends, stresses badgers, by destabilising their bioclimatic niche. Summer droughts cause mortality, even driving genetic selection; and while milder winters generally benefit badgers, less time spent in torpor leads to more road casualties. Similar effects also operate over a wide spatial scale in Ireland, impacting regional badger densities and bodyweights. That even an adaptable, generalist musteloid is so variously susceptible to weather conditions highlights how climate change places many species and ecosystems at risk.
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Hass, Christine C., et Jerry W. Dragoo. Competition and coexistence in sympatric skunks. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198759805.003.0024.
Texte intégralRésumé :
Ecological niches of three species of skunks (Mephitidae: Conepatus leuconotus, Mephitis mephitis, M. macroura) in and near their overlap zone in the American Southwest were studied to determine if competition may be limiting distribution of these species. A species distribution model developed in MaxEnt was used to identify suitable habitat for each species, from which contact zones for each species pair were identified. Principal components derived from habitat and climate variables inside and outside of contact zones for each species, and between species pairs within the contact zone were then compared. Species differed in environmental space inside and outside of contact zones, but species pairs did not differ within contact zones, indicating no evidence of competitive exclusion, and possible niche convergence at a broad spatial scale
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Edwards, Martin. Plankton and Global Change. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199233267.003.0007.
Texte intégralRésumé :
Global change caused by human activities has had large consequences for the Earth's biosphere through such effects as climate warming, pollution, loss of biodiversity, unsustainable exploitation of resources, loss of habitats, and alterations to nutrient cycles. These changes have accelerated over the last 50 years as human populations have sharply grown, coupled with unsustainable economic practices. The marine pelagic realm, the habitat for planktonic organisms, is the largest ecological habitat on the planet, occupying 71% of the planetary surface. This chapter focuses on the effects of global changes caused by human activities on marine plankton. It introduces some key concepts of plankton ecology such as the ecological niche concept, plankton succession, and the use of planktonic indicators to monitor these changes.
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Brönmark, Christer, et Lars-Anders Hansson. The Biology of Lakes and Ponds. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198713593.001.0001.
Texte intégralRésumé :
The Biology of Lakes and Ponds focuses on the interactions between the abiotic frame, such as turbulence, temperature, pH and nutrients, and the organisms, including interactions with and among organisms at the individual, population and community level. The book fills this niche between traditional limnology and evolutionary ecology by focusing on physiological, morphological and behavioural adaptations among organisms to abiotic and biotic factors and how interactions between biotic processes and abiotic constraints determine the structure and dynamics of lake and pond systems. In addition, the book describes and analyses the causes and consequences of human activities on freshwater organisms and ecosystems and covers longstanding environmental threats, such as eutrophication and acidification, as well as novel threats, such as biodiversity loss, use of everyday chemicals and global climate change. However, also signs of improvement and the possibilities to restore degraded ecosystems are discussed and provide hope for future generations.
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Van De Vliert, Evert. Climato‐economic Niches of Employee Well‐Being. Oxford University Press, 2008. http://dx.doi.org/10.1093/oxfordhb/9780199211913.003.0021.
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Mabey, Richard. Turned Out Nice Again : Living with the Weather. TBS/GBS/Transworld, 2013.
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Turned Out Nice Again : On Living with the Weather. Profile Books Limited, 2019.
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Finn, Chester E., et Andrew E. Scanlan. Learning in the Fast Lane. Princeton University Press, 2019. http://dx.doi.org/10.23943/princeton/9780691178721.001.0001.
Texte intégralRésumé :
The Advanced Placement (AP) program stands as the foremost source of college-level academics for millions of high school students in the United States and beyond. More than 22,000 schools now participate in it, across nearly forty subjects, from Latin and art to calculus and computer science. Yet remarkably little has been known about how this nongovernmental program became one of the greatest success stories in K–12 education—until now. This book offers an account of one of the most important educational initiatives of our time. The book traces the story of AP from its mid-twentieth-century origins as a niche benefit for privileged students to its emergence as a springboard to college for high schoolers nationwide, including hundreds of thousands of disadvantaged youth. Today, AP not only opens new intellectual horizons for smart teenagers, but also strengthens school ratings, attracts topflight teachers, and draws support from philanthropists, reformers, and policymakers. At the same time, it faces numerous challenges, including rival programs, curriculum wars, charges of elitism, the misgivings of influential universities, and the difficulty of infusing rigor into schools that lack it. In today's polarized climate, can AP maintain its lofty standards and surmount the problems that have sunk so many other bold education ventures?
Chapitres de livres sur le sujet "Climate niche"
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Hassen, Nabilah B., et Dinesh Surroop. « Unconventional Local Climate Change Niche in Mauritius ». Dans Handbook of Climate Change Management, 1–12. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-22759-3_233-1.
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Pinto-Ledezma, Jesús N., et Jeannine Cavender-Bares. « Using Remote Sensing for Modeling and Monitoring Species Distributions ». Dans Remote Sensing of Plant Biodiversity, 199–223. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-33157-3_9.
Texte intégralRésumé :
AbstractInterpolated climate surfaces have been widely used to predict species distributions and develop environmental niche models. However, the spatial coverage and density of meteorological sites used to develop these surfaces vary among countries and regions, such that the most biodiverse regions often have the most sparsely sampled climatic data. We explore the potential of satellite remote sensing (S-RS) products—which have consistently high spatial and temporal resolution and nearly global coverage—to quantify species-environment relationships that predict species distributions. We propose several new environmental metrics that take advantage of high temporal resolution in S-RS data and compare these approaches to classic climate-only approaches using the live oaks (Quercus section Virentes) as a case study. We show that models perform similarly but for some species, particularly in understudied regions, show less precision in predicting spatial distribution. These results provide evidence supporting efforts to enhance environmental niche models and species distribution models (ENMs/SDMs) with S-RS data and, when combined with other approaches for species detection, will likely enhance our ability to monitor biodiversity globally.
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Jaeger, Lars. « The Path of Renewable Electricity : From Niche Products to the High-Tech Innovations of the Future ». Dans Ways Out of the Climate Catastrophe, 125–39. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-85132-3_9.
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Mubaya, Chipo Plaxedes, Francis Themba Mugabe et Sue Walker. « Carving a Niche for the Social Sciences in Transdisciplinary Research on Climate Change Adaptation in Southern African Agriculture ». Dans Global Sustainability, 107–17. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16477-9_6.
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Prasad, Anantha M. « Machine Learning for Macroscale Ecological Niche Modeling - a Multi-Model, Multi-Response Ensemble Technique for Tree Species Management Under Climate Change ». Dans Machine Learning for Ecology and Sustainable Natural Resource Management, 123–39. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-96978-7_6.
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Baltensperger, Andrew P. « Using Interactions among Species, Landscapes, and Climate to Inform Ecological Niche Models : A Case Study of American Marten (Martes americana) Distribution in Alaska ». Dans Machine Learning for Ecology and Sustainable Natural Resource Management, 205–25. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-96978-7_10.
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Hudson, Irene L., et Marie R. Keatley. « Singular Spectrum Analysis : Climatic Niche Identification ». Dans Phenological Research, 393–424. Dordrecht : Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3335-2_18.
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Harley, Trevor A. « Nice Weather for the Time of Year : The British Obsession with the Weather 1 ». Dans Weather, Climate, Culture, 103–18. London : Routledge, 2021. http://dx.doi.org/10.4324/9781003103264-8.
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Hudson, Irene L., In Kang et Marie R. Keatley. « Wavelet Analysis of Flowering and Climatic Niche Identification ». Dans Phenological Research, 361–91. Dordrecht : Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3335-2_17.
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Morgan, Lynette. « Background and history of hydroponics and protected cultivation. » Dans Hydroponics and protected cultivation : a practical guide, 1–10. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781789244830.0001.
Texte intégralRésumé :
Abstract Along with new types of protected cropping structures, materials and technology, the range and diversity of hydroponic crops grown are also expanding. While the greenhouse mainstays of nursery plants, tomatoes, capsicum, cucumber, salad vegetables and herbs will continue to expand in volume, newer, speciality and niche market crops are growing in popularity. These include new cut flower species, potted plants and ornamental crops, and a growing trend in the commercial production of medicinal herbs using high-technology methods such as aeroponics. Exotic culinary herbs such as wasabi, dwarf fruiting trees and spices such as ginger and vanilla are now grown commercially in protected cropping structures, while many home gardeners continue to take up hydroponics and protected cropping as both a hobby and a means of growing produce. Protected cropping and hydroponic methods will further their expansion into hostile climates which never previously allowed the production of food.
Actes de conférences sur le sujet "Climate niche"
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Kline, Thomas. « Ontogenetic, Temporal, and Spatial Variation of Feeding Niche in an Unexploited Population of Walleye Pollock (Theragra chalcogramma) ». Dans Resiliency of Gadid Stocks to Fishing and Climate Change. Alaska Sea Grant College Program, 2008. http://dx.doi.org/10.4027/rgsfcc.2008.14.
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« A Local Application of Climate Niche Models for Chinese Fir and Possible Adaptation Strategies under a Changing Climate -- A Case Study in Fujian Province, China ». Dans 2018 International Conference on Biomedical Engineering, Machinery and Earth Science. Francis Academic Press, 2018. http://dx.doi.org/10.25236/bemes.2018.006.
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Saupe, Erin E., Huijie Qiao, Alex Farnsworth, Yannick Donnadieu, Dan J. Lunt, Alexandre Pohl, Navjit Sagoo, Paul J. Valdes et Seth Finnegan. « COMBINED CLIMATE AND ECOLOGICAL NICHE MODELING PREDICTS THE RELATIVE SEVERITY OF MARINE EXTINCTIONS DURING THREE PHANEROZOIC GREENHOUSE-ICEHOUSE TRANSITIONS ». Dans GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-301245.
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Hustad, Carl-W. « Deployment of Low and Zero Emission Fossil Fuel Power Generation in Emerging Niche Markets ». Dans ASME Turbo Expo 2008 : Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50106.
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The opportunities for near-term implementation of low and zero-emission fossil fuel power generation using Carbon Capture and Storage (CCS) is emerging in niche markets. This is primarily motivated by regulations following a growing awareness regarding the potential impact of climate-change, and partly the opportunities for use of carbon-dioxide (CO2) with enhanced oil recovery (EOR). However there remain significant technology, engineering, investment and political barriers that need to be overcome before CCS can be accepted as commercially mature for the power generation industry and the finance community. The risk with early projects is high, while collaboration and trust between government, industry and investors will also be needed to commercialize the technology. With an emerging sense of urgency regarding a global consensus for tackling climate-change, one also observes that technology pathways are integrated with political agendas and it becomes important to roadmap a commercial strategy for the respective technologies taking account of government requirements for compromise and burden sharing. To some extent this can also impact on comparative choices for the most cost-effective technologies that are supported through to future commercial deployment. The situation is complicated by the fact that technology choice—be it pre-combustion, post-combustion or oxy-combustion—remains an open question, where parties are probably influenced by their historical expertise, available hardware and near-term perception of future carbon challenge. The fact that energy, materials and engineering costs have been escalating rapidly while there is also a fundamental paradigm change occurring, somewhat undermines the use of historical data and past experience to predict business opportunities for the future. Within this context the paper considers on-going carbon market evolution in three regions, namely Texas, North Europe and Canada, seen from a technology and project developer perspective. The paper applies updated project engineering costs for capture from natural gas (NG) and coal using post- and oxy-combustion technology. Under all circumstances projects still exhibit poor economic return on invested capital and depend on government participation; they therefore remain unattractive to the investment community. But perhaps more important is the current perception of technology and market risk which also appears to undermine motivation to make significant commitments when evaluating projects within the old paradigm. However such a situation is not politically sustainable and a new paradigm must emerge. This will occur through regulation and significant changes in pricing in the energy and commodity market—including valuation of captured and avoided CO2. And this will also impact on the relative merits of various technology options. For the time being these discussion and results are only indicative of how a new paradigm and evolving technology may become “game-changing”, but the paper does attempt to provide some foresight into future opportunities.
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Nedealcov, Maria, Ala Donica et Nicolae Grigoras. « Evaluări privind impactul secetei asupra speciilor de stejari (Quercus Robur, Q. Petraea, Q.Pubescens) în condiții de aridizare a climei ». Dans Starea actuală a componentelor de mediu. Institute of Ecology and Geography, Republic of Moldova, 2019. http://dx.doi.org/10.53380/9789975315593.27.
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The growth and survival of forests in the future, especially in the peripheral and transition areas of ecosystems, such as the Moldavian oak forests, depend directly on temperature changes and the amount of atmospheric precipitation. The purpose of this paper is to determine the potential impact of climate aridization on native species - oaks (Quercus robur, Q. petraea, Q.pubescens) in correlation with ecological niche for these species and identifying the vulnerability zones of forests versus the drought (reproduced by various values of the DeMartonne Index). It has been determined that mesophilic oak specie, during the vegetation period, in the central and southern part of the country, under more dry, more arid conditions of development, will feel changes in the sensitivity to water scarcity, changes in the compositional structure of the respective ecosystems and chorological displacements of the species (limiting the growth area of the Quercus robur, Q. petraea and advancing of Q.pubescens to the central part of country).
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Rodgers, Colin, et Colin F. McDonald. « Small Recuperated Gas Turbine APU Concept to Abate Concern About Emissions, High Fuel Cost, and Noise ». Dans ASME Turbo Expo 2007 : Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27913.
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During the last decade microturbines in the 30 to 250 kW power range have been in service, but they have not been produced in significant enough quantities to impact the DG market due to a combination of factors including their high cost, modest efficiency, utility institutional concerns, and low interest in CHP use in the USA, although the latter could change as a result of fuel cost escalation. Very small gas turbines (ie. less than 10 kW) have been investigated periodically over the years, mainly for potential military use, but to date have not found a niche. This could well change with over 20 states now having instigated idling regulations that limit or prohibit heavy duty truck diesel engine idling. With emphasis on reducing emissions and noise levels this essentially implies that in the future a small APU will be required to provide the truck’s stationary electrical needs and cabin climate control. While there will be several power source types vying for this potentially large market, a small gas turbine APU is viewed as having attractive features which include low emissions, low acoustic signature, vibration-free operation, compact and light weight package, obviates the need for oil lubrication and liquid coolant systems, ease of cold weather starting, immediate response, and the use of fuel from the truck tank. In this paper a small recuperated gas turbine APU concept rated at 5kW is discussed including component design considerations, layout features, engine performance, and target cost. The conservative design of the APU is based on the use of existing materials and state-of-the-art gas turbine technology, and is amenable to high volume automated manufacturing processes. A competitive cost is projected if the proposed APU of modular construction was fabricated in large quantities like the production of vehicular turbochargers in Europe.
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Antell, Gwen S., Isabel S. Fenton, Paul J. Valdes et Erin E. Saupe. « THERMAL NICHES OF PLANKTONIC FORAMINIFERA ARE STATIC THROUGHOUT GLACIAL-INTERGLACIAL CLIMATE CHANGE ». Dans GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-357068.
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Fartmannn, Thomas, et Gregor Stuhldreher. « Threatened grassland butterflies as indicators of microclimatic niches along an elevational gradient – Implications for conservation in times of climate change ». Dans 5th European Congress of Conservation Biology. Jyväskylä : Jyvaskyla University Open Science Centre, 2018. http://dx.doi.org/10.17011/conference/eccb2018/108142.
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Barbosa, Fábio C. « Fuel Cell Rail Technology Review : A Tool for an Autonomous Rail Electrifying Strategy ». Dans 2019 Joint Rail Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/jrc2019-1223.
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Rail (passenger and freight) industry has been under pressure to tackle climate change, local and noise emissions. The current available powertrain technologies to reach the reduced greenhouse (GHG) and zero local emissions demands are electric (fed from the power grid), battery and fuel cell. However, the associated infrastructure costs (electrical equipments and the required overhead catenary infrastructure) have limited the electric option to heavy loaded corridors. Battery electric powered rail vehicles could be another potential option, but their system recharging requirements might significantly limit the system’s availability, thus, impacting the rail vehicle’s on-the-job performance. The recent breakthrough of fuel cell technology in the heavy duty road industry (mainly transit buses), allied with its operational flexibility and environmental performance has opened the way for this groundbreaking technology in the rail industry. Fuel cells generate electricity onboard, using hydrogen or hydrogen rich hydrocarbon fuels. Electricity is, then, stored in batteries or fed directly into a rail vehicle’s high voltage propulsion system. From an operational perspective, fuel cell powered rail vehicles might replace diesel ones in a one-to-one relationship, with the same range and running times, and a more efficient and less noisy powertrain. Moreover, the on-site refilling station is the only additional infrastructure element required, compared to diesel rail vehicle baselines. In short, fuel cell technology might offer a long term local zero emission alternative, fast refuelling (like diesel), flexibility, with self-electrification, integration with a renewable energy source and a quiet operation. Given their outstanding operational and environmental features, several rail market niches might be addressed by the fuel cell technology: i) light rail and trams in urban environments; ii) commuter and regional trains operating on non electrified tracks; iii) shunt or switch locomotives in rail yards (generally located on central portions of large cities or at the crossroads of major rail distribution hubs); iv) underground mining locomotives, and v) line haul locomotives. Since 2002, there has been an intense activity in the global development of fuel cell technology for the rail industry for both passenger and freight markets. This work is supposed to present, based on the compilation of information from a multitude of acknowledged sources, a review of fuel cell rail technology, followed by an overview of fuel cell rail experiences and feasibility studies, highlighting their main outcomes, as well as fuel cell technology potential to offer lower operational costs (fuel and maintenance) and improved performance for the rail industry.