Bibliografias temáticas / Species niche

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Literatura científica selecionada sobre o tema "Species niche"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 8 de fevereiro de 2022

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Artigos de revistas sobre o assunto "Species niche"

Liu, Chunlong, Christian Wolter, Weiwei Xian e Jonathan M. Jeschke. "Most invasive species largely conserve their climatic niche". Proceedings of the National Academy of Sciences 117, n.º 38 (3 de setembro de 2020): 23643–51. http://dx.doi.org/10.1073/pnas.2004289117.

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The ecological niche is a key concept for elucidating patterns of species distributions and developing strategies for conserving biodiversity. However, recent times are seeing a widespread debate whether species niches are conserved across space and time (niche conservatism hypothesis). Biological invasions represent a unique opportunity to test this hypothesis in a short time frame at the global scale. We synthesized empirical findings for 434 invasive species from 86 studies to assess whether invasive species conserve their climatic niche between native and introduced ranges. Although the niche conservatism hypothesis was rejected in most studies, highly contrasting conclusions for the same species between and within studies suggest that the dichotomous conclusions of these studies were sensitive to techniques, assessment criteria, or author preferences. We performed a consistent quantitative analysis of the dynamics between native and introduced climatic niches reported by previous studies. Our results show there is very limited niche expansion between native and introduced ranges, and introduced niches occupy a position similar to native niches in the environmental space. These findings support the niche conservatism hypothesis overall. In particular, introduced niches were narrower for terrestrial animals, species introduced more recently, or species with more native occurrences. Niche similarity was lower for aquatic species, species introduced only intentionally or more recently, or species with fewer introduced occurrences. Climatic niche conservatism for invasive species not only increases our confidence in transferring ecological niche models to new ranges but also supports the use of niche models for forecasting species responses to changing climates.

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Sillero, Neftalí, Elena Argaña, Cátia Matos, Marc Franch, Antigoni Kaliontzopoulou e Miguel A. Carretero. "Local Segregation of Realised Niches in Lizards". ISPRS International Journal of Geo-Information 9, n.º 12 (21 de dezembro de 2020): 764. http://dx.doi.org/10.3390/ijgi9120764.

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Species can occupy different realised niches when sharing the space with other congeneric species or when living in allopatry. Ecological niche models are powerful tools to analyse species niches and their changes over time and space. Analysing how species’ realised niches shift is paramount in ecology. Here, we examine the ecological realised niche of three species of wall lizards in six study areas: three areas where each species occurs alone; and three areas where they occur together in pairs. We compared the species’ realised niches and how they vary depending on species’ coexistence, by quantifying niche overlap between pairs of species or populations with the R package ecospat. For this, we considered three environmental variables (temperature, humidity, and wind speed) recorded at each lizard re-sighting location. Realised niches were very similar when comparing syntopic species occurring in the same study area. However, realised niches differed when comparing conspecific populations across areas. In each of the three areas of syntopy, the less abundant species shift its realised niche. Our study demonstrates that sympatry may shift species’ realised niche.

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Figueiredo, Giovanna Corrêa e., Karina Bohrer do Amaral e Marcos César de Oliveira Santos. "Cetaceans along the southeastern Brazilian coast: occurrence, distribution and niche inference at local scale". PeerJ 8 (5 de outubro de 2020): e10000. http://dx.doi.org/10.7717/peerj.10000.

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It is deemed important to understand cetacean occurrence and distribution to comprehend their ecological roles. The geographical occurrence of species’ niche can be used to better describe their potential distribution. The niche can be defined using environmental variables. Those variables are considered static and not affected by biological activities. The present study goal was to assess the occurrence and distribution of cetaceans along the southeastern Brazilian coast, as well as to define the fundamental and realized niche of each species and to investigate niche overlap at local scale. The environmental requirements for each species were also investigated throughout statistical tests. Sighting data were obtained through oceanographic surveys conducted between 2012 and 2015. The environmental variables available on MARSPEC and the software NicheA were used for the ecological niche modeling. A total of twelve cetacean species were identified and the potential distribution areas of the six commonest ones were defined. Even though the species presented different environmental preferences, most of them had partial overlap among niches and potential distribution areas. The environmental heterogeneity of the study area might support the co-occurrence of different species with different environmental requirements.

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Srivastava, Vivek, Wanwan Liang, Melody A. Keena, Amanda D. Roe, Richard C. Hamelin e Verena C. Griess. "Assessing Niche Shifts and Conservatism by Comparing the Native and Post-Invasion Niches of Major Forest Invasive Species". Insects 11, n.º 8 (29 de julho de 2020): 479. http://dx.doi.org/10.3390/insects11080479.

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Invasive species experience biotic and abiotic conditions that may (or may not) resemble their native environment. We explored the methodology of determining climatic niches and compared the native and post-invasion niches of four invasive forest pests to determine if these species experienced shifts or changes in their new climatic niches. We used environmental principle components analysis (PCA-env) method to quantify climatic niche shifts, expansions, and temporal changes. Furthermore, we assessed the effect of variable selection in the delineation and comparison of niche space. We found that variable selection influenced the delineation and overlap of each niche, whereas the subset of climatic variables selected from the first two PCA-env axes explained more variance in environmental conditions than the complete set of climatic variables for all four species. Most focal species showed climatic niche shifts in their invasive range and had not yet fully occupied the available niche within the invaded range. Our species varied the proportion of niche overlap between the native and invasive ranges. By comparing native and invasive niches, we can help predict a species’ potential range expansion and invasion potential. Our results can guide monitoring and help inform management of these and other invasive species.

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Allgeier, Jacob E., Thomas C. Adam e Deron E. Burkepile. "The importance of individual and species-level traits for trophic niches among herbivorous coral reef fishes". Proceedings of the Royal Society B: Biological Sciences 284, n.º 1856 (14 de junho de 2017): 20170307. http://dx.doi.org/10.1098/rspb.2017.0307.

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Resolving how species compete and coexist within ecological communities represents a long-standing challenge in ecology. Research efforts have focused on two predominant mechanisms of species coexistence: complementarity and redundancy. But findings also support an alternative hypothesis that within-species variation may be critical for coexistence. Our study focuses on nine closely related and ecologically similar coral reef fish species to test the importance of individual- versus species-level traits in determining the size of dietary, foraging substrate, and behavioural interaction niches. Specifically, we asked: (i) what level of biological organization best describes individual-level niches? and (ii) how are herbivore community niches partitioned among species, and are niche widths driven by species- or individual-level traits? Dietary and foraging substrate niche widths were best described by species identity, but no level of taxonomy explained behavioural interactions. All three niches were dominated by only a few species, contrasting expectations of niche complementarity. Species- and individual-level traits strongly drove foraging substrate and behavioural niches, respectively, whereas the dietary niche was described by both. Our findings underscored the importance of species-level traits for community-level niches, but highlight that individual-level trait variation within a select few species may be a key driver of the overall size of niches.

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Pagel, Jörn, Martina Treurnicht, William J. Bond, Tineke Kraaij, Henning Nottebrock, AnneLise Schutte-Vlok, Jeanne Tonnabel, Karen J. Esler e Frank M. Schurr. "Mismatches between demographic niches and geographic distributions are strongest in poorly dispersed and highly persistent plant species". Proceedings of the National Academy of Sciences 117, n.º 7 (6 de fevereiro de 2020): 3663–69. http://dx.doi.org/10.1073/pnas.1908684117.

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The ecological niche of a species describes the variation in population growth rates along environmental gradients that drives geographic range dynamics. Niches are thus central for understanding and forecasting species’ geographic distributions. However, theory predicts that migration limitation, source–sink dynamics, and time-lagged local extinction can cause mismatches between niches and geographic distributions. It is still unclear how relevant these niche–distribution mismatches are for biodiversity dynamics and how they depend on species life-history traits. This is mainly due to a lack of the comprehensive, range-wide demographic data needed to directly infer ecological niches for multiple species. Here we quantify niches from extensive demographic measurements along environmental gradients across the geographic ranges of 26 plant species (Proteaceae; South Africa). We then test whether life history explains variation in species’ niches and niche–distribution mismatches. Niches are generally wider for species with high seed dispersal or persistence abilities. Life-history traits also explain the considerable interspecific variation in niche–distribution mismatches: poorer dispersers are absent from larger parts of their potential geographic ranges, whereas species with higher persistence ability more frequently occupy environments outside their ecological niche. Our study thus identifies major demographic and functional determinants of species’ niches and geographic distributions. It highlights that the inference of ecological niches from geographical distributions is most problematic for poorly dispersed and highly persistent species. We conclude that the direct quantification of ecological niches from demographic responses to environmental variation is a crucial step toward a better predictive understanding of biodiversity dynamics under environmental change.

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Fan, Yan Rong, Shuang Lin Chen, Hua Lin, Qing Ping Yang, Yi Cong Hong e Zi Wu Guo. "Niches of Major Associated Species in Natural Mixed Moso Bamboo Forests". Advanced Materials Research 726-731 (agosto de 2013): 4298–302. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.4298.

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Niche characteristics of nineteen main associated tree populations in moso bamboo mixed forests in Luoboyan Natural Reserve were investigated. The results show that associated populations ofSarcandra glabra,Ilex purpureaandEurya japonica, with high important values have great capacity of adapting to environment and also have broader niche breadths.Liquidamba formosanaseldom appear as associated trees and have narrow niche breadth.Castanopsis fargesii,Engelhardia fenzelii,Castanopsis kawakamii,Schima superba,Nyssa aquaticandCarpinus turczaninowiihave close niche breadth and similar distribution range within the community.Ilex purpurea-Castanopsis fargesii,Ilex purpurea-Engelhardia fenzelii,Engelhardia fenzelii-Liquidamba formosana,Castanopsis kawakamii-Dendropanax dentiger,Rhododendron pulchrum-Schima superba,Dendropanax dentiger-Castanopsis lamontiiandCastanopsis lamontii-Carpinus turczaninowiihave high niche overlaps which prove that species having similar or same circumstances demands high niche overlap indexes. Species with broader niches have more chances for niche overlap with other species.Sarcandra glabradistributes widely and has broad niche breadth but low overlap index with other species, which indicates that species with broad niche breadth is not inevitable to have broad niche overlap with other species.

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Gómez, Camila, Elkin A. Tenorio, Paola Montoya e Carlos Daniel Cadena. "Niche-tracking migrants and niche-switching residents: evolution of climatic niches in New World warblers (Parulidae)". Proceedings of the Royal Society B: Biological Sciences 283, n.º 1824 (10 de fevereiro de 2016): 20152458. http://dx.doi.org/10.1098/rspb.2015.2458.

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Differences in life-history traits between tropical and temperate lineages are often attributed to differences in their climatic niche dynamics. For example, the more frequent appearance of migratory behaviour in temperate-breeding species than in species originally breeding in the tropics is believed to have resulted partly from tropical climatic stability and niche conservatism constraining tropical species from shifting their ranges. However, little is known about the patterns and processes underlying climatic niche evolution in migrant and resident animals. We evaluated the evolution of overlap in climatic niches between seasons and its relationship to migratory behaviour in the Parulidae, a family of New World passerine birds. We used ordination methods to measure seasonal niche overlap and niche breadth of 54 resident and 49 migrant species and used phylogenetic comparative methods to assess patterns of climatic niche evolution. We found that despite travelling thousands of kilometres, migrants tracked climatic conditions across the year to a greater extent than tropical residents. Migrant species had wider niches than resident species, although residents as a group occupied a wider climatic space and niches of migrants and residents overlapped extensively. Neither breeding latitude nor migratory distance explained variation among species in climatic niche overlap between seasons. Our findings support the notion that tropical species have narrower niches than temperate-breeders, but does not necessarily constrain their ability to shift or expand their geographical ranges and become migratory. Overall, the tropics may have been historically less likely to experience the suite of components that generate strong selection pressures for the evolution of migratory behaviour.

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Bar-Massada, Avi. "Complex relationships between species niches and environmental heterogeneity affect species co-occurrence patterns in modelled and real communities". Proceedings of the Royal Society B: Biological Sciences 282, n.º 1813 (22 de agosto de 2015): 20150927. http://dx.doi.org/10.1098/rspb.2015.0927.

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Species co-occurrence analysis is commonly used to assess how interspecific interactions dictate community assembly. Non-random co-occurrences, however, may also emerge from niche differences as well as environmental heterogeneity. The relationships between species co-occurrence patterns, environmental heterogeneity and species niches are not fully understood, due to complex interactions among them. To analyse the relationships among these patterns and processes, I developed synthetic community models and analysed a large dataset of tree species across the conterminous United States. Niche overlap and environmental heterogeneity had significant and contrasting effects on species co-occurrence patterns, in both modelled and real communities. Niche breadth, in turn, affected the effect sizes of both variables on species co-occurrence patterns. The effect of niche breadth on the relationship between co-occurrence and niche overlap was markedly consistent between modelled and real communities, while its effect on the relationship between co-occurrence and environmental heterogeneity was mostly consistent between real and modelled data. The results of this analysis highlight the complex and interactive effects of species niche overlap, niche breadth and environmental heterogeneity on species co-occurrence patterns. Therefore, inferring ecological processes from co-occurrence patterns without accounting for these fundamental characteristics of species and environments may lead to biased conclusions.

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Lavergne, Sébastien, Margaret E. K. Evans, Ian J. Burfield, Frederic Jiguet e Wilfried Thuiller. "Are species' responses to global change predicted by past niche evolution?" Philosophical Transactions of the Royal Society B: Biological Sciences 368, n.º 1610 (19 de janeiro de 2013): 20120091. http://dx.doi.org/10.1098/rstb.2012.0091.

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Predicting how and when adaptive evolution might rescue species from global change, and integrating this process into tools of biodiversity forecasting, has now become an urgent task. Here, we explored whether recent population trends of species can be explained by their past rate of niche evolution, which can be inferred from increasingly available phylogenetic and niche data. We examined the assemblage of 409 European bird species for which estimates of demographic trends between 1970 and 2000 are available, along with a species-level phylogeny and data on climatic, habitat and trophic niches. We found that species' proneness to demographic decline is associated with slow evolution of the habitat niche in the past, in addition to certain current-day life-history and ecological traits. A similar result was found at a higher taxonomic level, where families prone to decline have had a history of slower evolution of climatic and habitat niches. Our results support the view that niche conservatism can prevent some species from coping with environmental change. Thus, linking patterns of past niche evolution and contemporary species dynamics for large species samples may provide insights into how niche evolution may rescue certain lineages in the face of global change.

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Mais fontes

Teses / dissertações sobre o assunto "Species niche"

Janse, Van Vuuren Adriaan. "Niche Occupation in Biological Species Competition". Thesis, Stellenbosch : University of Stellenbosch, 2008. http://hdl.handle.net/10019.1/2932.

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Thesis (MSc (Logistics))--University of Stellenbosch, 2008.
The primary question considered in this study is whether a small population of a biological species introduced into a resource-heterogeneous environment, where it competes for these resources with an already established native species, will be able to invade successfully. A two-component autonomous system of reaction-diffusion equations with spatially inhomogeneous Lotka-Volterra competitive reaction terms and diffusion coefficients is derived as the governing equations of the competitive scenario. The model parameters for which the introduced species is able to invade describe the realized niche of that species. A linear stability analysis is performed for the model in the case where the resource heterogeneity is represented by, and the diffusion coefficients are, two-toned functions. In the case where the native species is not directly affected by the resource heterogeneity, necessary and sufficient conditions for successful invasion are derived. In the case where the native species is directly affected by the resource heterogeneity only sufficient conditions for successful invasion are derived. The reaction-diffusion equations employed in the model are deterministic. However, in reality biological species are subject to stochastic population perturbations. It is argued that the ability of the invading species to recover from a population perturbation is correlated with the persistence of the species in the niche that it occupies. Hence, invasion time is used as a relative measure to quantify the rate at which a species’ population distribution recovers from perturbation. Moreover, finite difference and spectral difference methods are employed to solve the model scenarios numerically and to corroborate the results of the linear stability analysis. Finally, a case study is performed. The model is instantiated with parameters that represent two different cultivars of barley in a hypothetical environment characterized by spatially varying water availability and the sufficient conditions for successful invasion are verified for this hypothetical scenario.

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Janse, van Vuuren Adriaan. "Niche occupation in biological species competition /". Link to the online version, 2008. http://hdl.handle.net/10019/753.

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Dutrieux, Mariane. "Spatio-temporal species distribution modeling: Application to invasive alien species’ monitoring". Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-224319.

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The developments of species distribution modeling techniques have brought new opportunities in the field of biological invasion management. In particular, statistical niche modeling for spatio-temporal predictions of species’ distribution is a widely spread tool that has proved its efficiency. The main purpose of this Master thesis is to study applicability of species distribution modeling to invasive alien species, with the aim of supporting efficient decision-making for their prevention. Some research questions are: how useful can species distribution modeling be for invasives’ prevention? Is distribution modeling technically feasible in the case of invasive species? What types of techniques are recommended to model distributions of IAS? What are the limits of such a tool? The methods employed to answer these questions are literature review and expert advice. I found that species distribution models can provide risk maps which are necessary to enable effective invasive alien species’ prevention. However intrinsic characteristics of invasives introduce uncertainties in the predictions made. Consequently several preliminary analyses should be conducted before applying the distribution model. Finally recommendations were made on the most appropriate distribution modeling technique to use depending on the urgency of the situation and the availability of data.
Utvecklingen av metoder för modelering av artdistribution har medfört nya möjligheter inom området hantering av biologiska invasioner. Statistisk nischmodelering för spatio-temporala förutsägelser av arters distribution är ett väl använt verktyg som har visat sig vara effektivt. Det övergripande målet med det här arbetet har varit att studera hur lämpad artmodelering är vid förebyggande av invasioner av främmande arter. Det har även undersökts huruvida metoden kan bidra till bättre och enklare beslutsfattande när det kommer till att förhindra sådana invasioner. Forskningsfrågorna lyder: hur användbart är fördelningsmodelering för förebyggande av spriding av invasiva arter? Är distributionsmodelering tekniskt genomförbar när det gäller invasiva arter? Vilka olika tekniker rekommenderas för att modelera spridningen av invasiva arter? Vilka begräsningar har modelerna? De metoder som används är litteraturöversikt och expertråd. Resultaten visar att artdistributionsmodelering kan bidra till att sammanställa riskkartor som är nödvändiga för att möjliggöra ett förebyggande arbete. Men speciella egenskaper hos de invasiva arterna som är svåra att förutse skapar osäkerheter i resultatet. Därför kan preliminära analyser med fördel genomföras innan modelering. I slutsatserna återfinns rekommendationer för vilken distributionsmodelteknik man bör använda, beroende av hur brådskande situationen är och om data finns tillgängligt.

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McHugh, Sean W. "Phylogenetic Niche Modeling". Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/104893.

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Projecting environmental niche models through time is a common goal when studying species response to climatic change. Species distribution models (SDMs) are commonly used to estimate a species' niche from observed patterns of occurrence and environmental predictors. However, a species niche is also shaped by non-environmental factors--including biotic interactions and dispersal barrier—truncating SDM estimates. Though truncated SDMs may accurately predict present-day species niche, projections through time are often biased by environmental condition change. Modeling niche in a phylogenetic framework leverages a clade's shared evolutionary history to pull species estimates closer towards phylogenetic conserved values and farther away from species specific biases. We propose a new Bayesian model of phylogenetic niche implemented in R. Under our model, species SDM parameters are transformed into biologically interpretable continuous parameters of environmental niche optimum, breadth, and tolerance evolving under multivariate Brownian motion random walk. Through simulation analyses, we demonstrated model accuracy and precision that improved as phylogeny size increased. We also demonstrated our model on a clade of eastern United States Plethodontid salamanders by accurately estimating species niche, even when no occurrence data is present. Our model demonstrates a novel framework where niche changes can be studied forwards and backwards through time to understand ancestral ranges, patterns of environmental specialization, and niche in data deficient species.
Master of Science
As many species face increasing pressure in a changing climate, it is crucial to understand the set of environmental conditions that shape species' ranges--known as the environmental niche--to guide conservation and land management practices. Species distribution models (SDMs) are common tools that are used to model species' environmental niche. These models treat a species' probability of occurrence as a function of environmental conditions. SDM niche estimates can predict a species' range given climate data, paleoclimate, or projections of future climate change to estimate species range shifts from the past to the future. However, SDM estimates are often biased by non-environmental factors shaping a species' range including competitive divergence or dispersal barriers. Biased SDM estimates can result in range predictions that get worse as we extrapolate beyond the observed climatic conditions. One way to overcome these biases is by leveraging the shared evolutionary history amongst related species to "fill in the gaps". Species that are more closely phylogenetically related often have more similar or "conserved" environmental niches. By estimating environmental niche over all species in a clade jointly, we can leverage niche conservatism to produce more biologically realistic estimates of niche. However, currently a methodological gap exists between SDMs estimates and macroevolutionary models, prohibiting them from being estimated jointly. We propose a novel model of evolutionary niche called PhyNE (Phylogenetic Niche Evolution), where biologically realistic environmental niches are fit across a set of species with occurrence data, while simultaneously fitting and leveraging a model of evolution across a portion of the tree of life. We evaluated model accuracy, bias, and precision through simulation analyses. Accuracy and precision increased with larger phylogeny size and effectively estimated model parameters. We then applied PhyNE to Plethodontid salamanders from Eastern North America. This ecologically-important and diverse group of lungless salamanders require cold and wet conditions and have distributions that are strongly affected by climatic conditions. Species within the family vary greatly in distribution, with some species being wide ranging generalists, while others are hyper-endemics that inhabit specific mountains in the Southern Appalachians with restricted thermal and hydric conditions. We fit PhyNE to occurrence data for these species and their associated average annual precipitation and temperature data. We identified no correlations between species environmental preference and specialization. Pattern of preference and specialization varied among Plethodontid species groups, with more aquatic species possessing a broader environmental niche, likely due to the aquatic microclimate facilitating occurrence in a wider range of conditions. We demonstrated the effectiveness of PhyNE's evolutionarily-informed estimates of environmental niche, even when species' occurrence data is limited or even absent. PhyNE establishes a proof-of-concept framework for a new class of approaches for studying niche evolution, including improved methods for estimating niche for data-deficient species, historical reconstructions, future predictions under climate change, and evaluation of niche evolutionary processes across the tree of life. Our approach establishes a framework for leveraging the rapidly growing availability of biodiversity data and molecular phylogenies to make robust eco-evolutionary predictions and assessments of species' niche and distributions in a rapidly changing world.

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Khondkaryan, Lusine. "Ecological niche modeling of rodent and flea species /". [Sedeh Boker, Israel] : Ben-Gurion University of the Negev, 2008. http://aranne5.lib.ad.bgu.ac.il/others/KhondkaryanLusine.pdf.

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Vergnon, Remi. "Testing niche-based and neutral mechanisms of species coexistence". Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527228.

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Brown, Michael Scott. "A Species-Conserving Genetic Algorithm for Multimodal Optimization". NSUWorks, 2010. http://nsuworks.nova.edu/gscis_etd/104.

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The problem of multimodal functional optimization has been addressed by much research producing many different search techniques. Niche Genetic Algorithms is one area that has attempted to solve this problem. Many Niche Genetic Algorithms use some type of radius. When multiple optima occur within the radius, these algorithms have a difficult time locating them. Problems that have arbitrarily close optima create a greater problem. This paper presents a new Niche Genetic Algorithm framework called Dynamic-radius Species-conserving Genetic Algorithm. This new framework extends existing Genetic Algorithm research. This new framework enhances an existing Niche Genetic Algorithm in two ways. As the name implies the radius of the algorithm varies during execution. A uniform radius can cause issues if it is not set correctly during initialization. A dynamic radius compensates for these issues. The framework does not attempt to locate all of the optima in a single pass. It attempts to find some optima and then uses a tabu list to exclude those areas of the domain for future iterations. To exclude these previously located optima, the framework uses a fitness sharing approach and a seed exclusion approach. This new framework addresses many areas of difficulty in current multimodal functional optimization research. This research used the experimental research methodology. A series of classic benchmark functional optimization problems were used to compare this framework to other algorithms. These other algorithms represented classic and current Niche Genetic Algorithms. Results from this research show that this new framework does very well in locating optima in a variety of benchmark functions. In functions that have arbitrarily close optima, the framework outperforms other algorithms. Compared to other Niche Genetic Algorithms the framework does equally well in locating optima that are not arbitrarily close. Results indicate that varying the radius during execution and the use of a tabu list assists in solving functional optimization problems for continuous functions that have arbitrarily close optima.

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Swisher, Robert E. "Paleobiogeographical and evolutionary analysis of Late Ordovician, C₅ sequence brachiopod species, with special reference to Rhynchonellid taxa". Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1245445583.

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Swisher, Robert E. "Paleobiogeographical and Evolutionary Analysis of Late Ordovician, C5 Sequence Brachiopod Species, with Special Reference to Rhynchonellid Taxa". Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1245445583.

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Gamboa, Badilla Nancy. "The role of species niche, species dispersal and landscape factors in the assembly of novel woody communities in metropolitan Mediterranean regions". Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/462039.

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Biological diversity in a global scale has been threaten seriously by anthropogenic disturbances in ecosystems. Changes in land cover and land use affect biodiversity, causing habitat loss and species extinction, or colonization and establishment of new communities. Such effects could happen in an outdated way between the time of the disturbance and species extinction or colonization. Landscape history, connectivity between habitat fragments and the dispersion of organism, shapes species diversity and influences extinction and colonization process. On the other hand, exotic plant invasion could drive the assembly of plant community in newly formed forests as a result of changes in land use. The present thesis aims to contribute to the knowledge of the assembly of new woody communities in forests and bushes of the metropolitan region of Barcelona. For this, the legacy of five historical land use trajectories and the environmental factors on the richness, diversity and equity of woody species in shrubland were analyzed. In addition, we evaluated the relationship between environmental and historical factors and species composition (Chapter 3). The results revealed that species richness and diversity are associated with both elevation and historical trajectories of land use, while equity only to elevation. The study did not detect spatial effects attributable to dispersion. The results indicated that both trajectories and environmental factors (niche) equally drive local community assembly, while dispersal seems to play a secondary role. The richness and diversity of species are affected by the use of the soil in the recent past (1956) and the composition by the oldest uses (1900). Additionally, the effect of urbanization on plant community assembly process in new periurban forests (Chapter 4) was evaluated. We explored the relationship between plant species richness and composition (dispersed by vertebrates and non-vertebrates), and forest patches history (pre-existing and recent), landscape pattern (forest connectivity and urbanization), habitat condition (forest, prairie grass, synanthropic, other) and environmental variables. The results showed that landscape habitat and structure are the main drivers of plant community assembly. However, as a side effect of forest history, extinction debt of scrub-meadow species must be considered. In addition, we found a greater colonization of synanthropic species and a credit for colonization of forest species dispersed by vertebrates in recent forests. The assemblage of new forests was characterized by the presence of species of previous habitats, rapid colonization of specialists and an increase of synanthropic species. Finally, the patterns of invasion by exotic plants and the influence of dispersal mechanism, environmental variables and landscape anthropization in these newly formed periurban forests were analyzed (Chapter 5). The presence, richness and abundance of exotic species dispersed by vertebrates and non - vertebrates in recent and preexisting forests were compared, taking into account landscape and environmental correlations. The results showed that metropolitan forests are more invaded than the rest of the province and the exotic flora on these forests are dominated by species dispersed by vertebrates. However, at the regional level a bias was found towards species dispersed by non-vertebrates. Forest fragmentation was associated with the presence, richness and coverage of plants dispersed by vertebrates; while urbanization was related with coverage of species dispersed by non-vertebrates. We suggest an association between forest history and plant dispersion syndromes, with species dispersed by vertebrates in ancient forests. No associations between exotic species composition and environmental factors were found, but not with forest history. The study notes a high degree of invasion of forests by alien species dispersed by vertebrates, which could colonize unaltered forests and persist and even expand throughout forest succession.
Las alteraciones antrópicas en los ecosistemas amenazan gravemente la diversidad biológica a escala global. Cambios en las cubiertas y usos del suelo afectan la biodiversidad, causando pérdida de hábitats y extinción de especies o bien colonización y establecimiento de especies que forman nuevas comunidades. Tales efectos podrían suceder de forma desfasada entre el momento de la perturbación y la extinción o colonización de las especies. Podrían además verse condicionados por la historia del paisaje, que influye sobre la diversidad de las especies, la conectividad entre fragmentos de hábitat y la dispersión de los organismos. Por otra parte, la invasión por plantas exóticas podría conducir el ensamblaje de la comunidad vegetal en bosques recién formados, como resultado de cambios en el uso de la tierra. La presente tesis tiene como objetivo aportar al conocimiento del ensamblaje de las nuevas comunidades leñosas en bosques y matorrales de la región metropolitana de Barcelona. Para ello se analizó el legado de cinco trayectorias históricas del uso del suelo y los factores ambientales sobre la riqueza, diversidad y equidad de especies leñosas en matorrales. Además, se evaluó la relación entre los factores ambientales e históricos y la composición de las especies (Capítulo 3). Los resultados revelaron que la riqueza y diversidad de estas especies se asocia tanto a la elevación como a las trayectorias históricas del uso de la tierra, mientras que la equidad sólo a la elevación. El estudio no detectó efectos espaciales atribuibles a la dispersión. Los resultados indicaron que tanto las trayectorias como los factores ambientales (nicho) impulsan de igual forma el ensamblaje de la comunidad a escala local, mientras que la dispersión parece desempeñar un papel secundario. La riqueza y diversidad de especies son afectadas por el uso del suelo en el pasado reciente (1956) y la composición por los usos más antiguos (1900). Por otra parte, se evaluó el efecto de la urbanización sobre el proceso de ensamblaje de las comunidades vegetales en los nuevos bosques periurbanos (Capítulo 4). Se exploró la relación entre la historia de parches forestales (preexistentes y recientes), el patrón del paisaje (conectividad forestal y urbanización), la condición del hábitat (bosque, matorral-pradera, sinantrópico, otro) y las variables ambientales con la riqueza y composición de las especies de plantas (dispersadas por vertebrados y no vertebrados). Los resultados mostraron que el hábitat y la estructura del paisaje son los principales impulsores del ensamblaje de la comunidad vegetal. Sin embargo, hay un efecto secundario de la historia del bosque, constituido por la deuda de extinción de especies de matorral-pradera. Además, se encontró una mayor colonización de especies sinantrópicas y un crédito de colonización de especies forestales dispersadas por vertebrados en los bosques recientes. El ensamblaje de bosques nuevos se caracterizó por la presencia de especies de hábitats anteriores, rápida colonización de especialistas y un aumento de especies sinantrópicas. Finalmente, se analizaron los patrones de invasión por plantas exóticas y la influencia del mecanismo de dispersión, las variables ambientales y la antropización del paisaje en estos bosques periurbanos recién formados (Capítulo 5). Se comparó la presencia, la riqueza y la abundancia de especies exóticas dispersadas por vertebradas y no vertebradas en bosques recientes y preexistentes, teniendo en cuenta las correlaciones paisajísticas y ambientales. Los resultados mostraron que los bosques metropolitanos están más invadidos que los del resto de la provincia y la flora exótica en estos bosques está dominada por especies dispersadas por vertebrados. Sin embargo, a nivel regional se encontró un sesgo hacia las especies dispersadas por no vertebrados. La fragmentación de los bosques se asoció con la presencia, riqueza y cobertura de plantas dispersadas por vertebrados; mientras que la urbanización con la cobertura de especies dispersadas por no vertebrados. Se sugiere una asociación entre la historia de los bosques y los síndromes de dispersión de las plantas, con especies dispersadas por vertebrados en bosques antiguos. No se detectaron asociaciones entre la historia del bosque y la composición de especies exóticas, sí con factores ambientales. El estudio advierte alto grado de invasión de bosques por especies exóticas dispersadas por vertebrados, las cuales podrían colonizar bosques inalterados y persistir e incluso expandirse a lo largo de la sucesión.

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Livros sobre o assunto "Species niche"

Flint, R. Warren. Niche characterization of dominant estuarine benthic species. College Station, Tex: Sea Grant College Program, Texas A&M University, 1986.

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Probatova, N. S., e V. P. Seledet︠s︡. Ecological ranges and ecological niches of plant species in the monsoon zone of Pacific Russia. Hauppauge, N.Y: Nova Science Publishers, 2012.

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Ecological speciation. Oxford: Oxford University Press, 2012.

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Tavares-Cromar, Annette Fatima. A study of niche overlap, species interactions and the food web of a macroinvertebrate riffle community in Duffin Creek, Ontario. Ottawa: National Library of Canada, 1990.

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Eldredge, Niles. Macroevolutionary dynamics: Species, niches, and adaptive peaks. New York: McGraw-Hill, 1989.

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Shomotsu no Nichi-Bei kankei: Riterashī-shi ni mukete. Tōkyō: Shinʾyōsha, 2007.

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W, Awdry, e Britt Allcroft. Spills & thrills: No more mr. nice engine. New York, NY: Random House, 2014.

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Have a nice day: Bond in motion : over 30 pop-ups for adults. New York, N.Y: C.N. Potter, 1986.

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Wevelsiep, Christian. Heilpädagogik, Bioethik und das Noch-Nicht-Seiende: Differenzphilosophische Reflexionen im Zeitalter der Bioethik. Bonn: Pahl-Rugenstein, 2005.

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Tokushu Kyōiku Fukyū Seminā (1997 Akita-shi Bunka Kaikan). Tokushu Kyōiku Fukyū Seminā hōkokusho: Tēma "ko ni taiōshita kyōiku naiyō hōhō no arikata to kyōiku shidō ni kansuru kōgakuteki ōyō" : Heisei 8-nendo : kaisaibi Heisei 9-nen 1-gatsu 23-nichi--24-nichi, kaijō Akita-shi Bunka Kaikan : shusai Kokuritsu Tokushu Kyōiku Sōgō Kenkyūjo, Akita-shi Bunka Kaikan. Yokosuka-shi: Kokuritsu Tokushu Kyōiku Sōgō Kenkyūjo, 1998.

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Capítulos de livros sobre o assunto "Species niche"

Rees, Paul A. "Community ecology and species interactions." In Key questions in ecology: a study and revision guide, 121–39. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789247572.0121.

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Abstract This chapter contains questions about the structure of biological communities, their development over time, and the interactions between the species living within them, especially competition, niche separation and predation.

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Hochkirch, Axel. "Niche Conservatism among Allopatric Species of the Grasshopper Genus Afrophlaeoba Jago, 1983 in the Eastern Arc Mountains (Tanzania)". In Relict Species, 145–58. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92160-8_7.

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Habel, Jan C., Bettina Augenstein, Marc Meyer, Gabriel Nève, Dennis Rödder e Thorsten Assmann. "Population Genetics and Ecological Niche Modelling Reveal High Fragmentation and Potential Future Extinction of the Endangered Relict Butterfly Lycaena helle". In Relict Species, 417–39. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92160-8_25.

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Rasko, David A. "Bacillus anthracis Plasmids: Species Definition or Niche Adaptation?" In Bacillus anthracis and Anthrax, 89–106. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2010. http://dx.doi.org/10.1002/9780470891193.ch6.

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Pinto-Ledezma, Jesús N., e Jeannine Cavender-Bares. "Using Remote Sensing for Modeling and Monitoring Species Distributions". In Remote Sensing of Plant Biodiversity, 199–223. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-33157-3_9.

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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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Quicke, Donald L. J., Buntika A. Butcher e Rachel A. Kruft Welton. "Species abundance, accumulation and diversity data." In Practical R for biologists: an introduction, 200–217. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245349.0200.

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Abstract Ecologists in particular are often interested in the species richness and diversity of groups of organisms, ranging from studies of small ecosystems to global patterns. In most cases it is not possible to count every individual or to detect every species, and so they use a variety of estimation methods and summary statistics that will be briefly introduce in this chapter. This chapter covers estimating species abundance and species richness by looking at accumulation curves. Analyzing diversity using tests such as the Shannon and Simpson diversity indices are also discussed. Finally, patterns of niche partitioning using the broken stick model are created. An example is shown, using transect surveys of butterflies in Papua New Guinea.

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Hikosaka, Kouki, Takehiro Sasaki, Chiho Kamiyama, Masatoshi Katabuchi, Shimpei Oikawa, Masaya Shimazaki, Hiroshi Kimura e Tohru Nakashizuka. "Trait-Based Approaches for Understanding Species Niche, Coexistence, and Functional Diversity in Subalpine Moorlands". In Structure and Function of Mountain Ecosystems in Japan, 17–40. Tokyo: Springer Japan, 2016. http://dx.doi.org/10.1007/978-4-431-55954-2_2.

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Gitay, Habiba, e A. D. Q. Agnew. "Plant community structure, connectance, niche limitation and species guilds within a dune slack grassland". In Progress in theoretical vegetation science, 241–48. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1934-1_21.

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Levy, Ruth. "Interspecific colony dispersion and niche relations of three large tropical rain forest ant species". In Monographiae Biologicae, 331–40. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1685-2_33.

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Trabalhos de conferências sobre o assunto "Species niche"

Both, Camila, e Taran Grant. "Acoustic invasion: How invasive species can impact native species acoustic niche?" In ICA 2013 Montreal. ASA, 2013. http://dx.doi.org/10.1121/1.4799249.

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Hopkins, Heidi E. "A species-rich genus of “desert” cockroaches and some factors contributing to species niche". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.105512.

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Nedealcov, Maria, Ala Donica e Nicolae Grigoras. "Evaluări privind impactul secetei asupra speciilor de stejari (Quercus Robur, Q. Petraea, Q.Pubescens) în condiții de aridizare a climei". In 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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Tan, Rui, Wei Li, Juan Wang, Fan Du e Yuming Yang. "Effects of Disturbance on Niche Breadth, Overlap, and Differentiation of Dominant Plant Species in Napa Plateau Wetland, Shangri-la". In 2013 Third International Conference on Intelligent System Design and Engineering Applications (ISDEA). IEEE, 2013. http://dx.doi.org/10.1109/isdea.2012.159.

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Kindler, Jessie Tayana Perugachy, Judith Zapata, Eduardo Ordonez, Theofilos Toulkeridis e Angelica Zapata. "The use of GIS in the Predictive Ecological Niche Modeling of Vector Species of the American Trypanosomiasis Disease (Chagas), in Ecuador". In 2020 Seventh International Conference on eDemocracy & eGovernment (ICEDEG). IEEE, 2020. http://dx.doi.org/10.1109/icedeg48599.2020.9096851.

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Adenan, Sakeenah, Jane Oja, Talaat Abdel-Fattah e Juha Alatalo. "Linking Soil Chemical Parameters and Fungal Diversity in Qatar". In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0068.

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Given the vast expanse of Qatar’s dryland ecosystems, agricultural productivity and soil stability is highly dependent on the diversity of soil microbiota. The soil environment is a heterogeneous habitat shaped by various components like chemical (organic matter, salinity and nutrients) and biological (fungal diversity and vegetation) properties that form multitudes of different microhabitats. Soil microbial diversity changes along environmental gradients. It is hypothesized that a “stable” microhabitat is one that is inhabited by a large diversity of established microorganisms that are best adapted to the niche. Microorganisms like fungi serve as the underlying biological drivers for biochemical processes within the soil. The key objective of this study is to evaluate the fungal diversity and abundance present within the Qatari soil using molecular-based tools and evaluate potential relationships between the identified fungal communities with chemical properties of the habitat. We found that the composition of fungi and AMF varied between different habitats around Qatar. Despite the lack of significant differences in the measured soil chemical parameters between sampled sites, it is evident that AMF species are more abundant than compared to that of other fungal species in most of the study sites; thus, suggesting that other factors like land use may also be an essential component explaining the variation in fungal communities.

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Abdel Samad, Rim, Zulfa Al Disi, Mohammad Ashfaq e Nabil Zouari. "The use of Principle Component Analysis and MALDI-TOF MS for the differentiation of mineral forming Virgibacillus and Bacillus species isolated from Sabkhas". In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0069.

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Occurrence of mineral forming and other bacteria in mats is well demonstrated. However, their high diversity shown by ribotyping was not explained, although it could explain the diversity of formed minerals. Common biomarkers as well as phylogenic relationships are useful tools to clustering the isolates and predict their potential role in the natural niche. In this study, combination of MALDI-TOF MS with PCA was shown a powerful tool to categorize 35 mineral forming bacterial strains isolated from Dohat Fshaikh sabkha, at northwest of Qatar (23 from decaying mats and 12 from living ones). 23 strains from decaying mats belong to Virgibacillus genus as identified by ribotyping and are shown highly involved in formation of protodolomite and a diversity of minerals. They were used as internal references in categorization of sabkha bacteria. Combination of isolation of bacteria on selective mineral forming media, their MALDI TOF MS protein profiling and PCA analysis established their relationship in a phyloproteomic based on protein biomarkers including m/z 4905, 3265, 5240, 6430, 7765, and 9815. PCA analysis clustered the studied strains into 3 major clusters, showing strong correspondence to the 3 phyloproteiomic groups that were established by the dendrogram. Both clustering analysis means have evidently demonstrated a relationship between known Virgibacillus strains and other related bacteria based on profiling of their synthesized proteins. Thus, larger populations of bacteria in mats can be easily screened for their potential to exhibit certain activities, which is of ecological, environmental and biotechnological significance.

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Banaszek, Jarosław, Marzena Leksy e Oimahmad Rahmonov. "The ecological diversity of vegetation within urban parks in the Dąbrowski Basin (southern Poland)". In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.005.

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The aim of this work is to present the diversity of flora in terms of ecological requirements. The research was conducted in the area of two urban parks in the area of two cities in southern Poland: Bedzin and Czeladz. These parks were established in different historical periods, and were planned (and are managed) differently. The results of the investigation have shown that the occurrence of 192 vascular species has been observed in the Gora Zamkowa (Castle Hill) Park, while in the Grabek park, 334 such species are known to exist. Such disparity is the result of the occurrence of micro-habitats and of the differences between the ways the two parks are managed. It is also due to these parks’ different functions. In the first case, the park area is protected by law. In the latter case, human activity has created a new ecological niche for organisms with a high degree of ecological tolerance. Based on the ecological values, the following groups of plants were distinguished: saxi-frages grasslands, xerothermic grasslands, beech forests, alder forests and artificial planted trees. Analysis has shown that ur-ban parks are potential places for growth various type of vegetation and also for increasing biodiversity, and can constitute particularly important hotspots for biodiversity in the cityscape, even if their primary role is recreational. As the study shows, the environment of a highly urbanized and industrialized region can also have a positive influence on ecological and floristic diversity.

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Kongsereeparp, Paitoon, Behzad Kashani e M. David Checkel. "A Stand-Alone Multi-Zone Model for Combustion in HCCI Engines". In ASME 2005 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/icef2005-1241.

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Because they have the potential for ultra low NOx emissions and high efficiency, Homogeneous Charge Compression Ignition (HCCI) engines have the potential to develop a significant niche. However, a narrow operating range, (bracketed by severe knock and misfire problems), presents a formidable obstacle to developing usable HCCI combustion systems. HCCI combustion is influenced by a complex array of operating variables including fuel octane quality, intake preheating temperature, compression ratio, equivalence ratio, exhaust gas recirculation and engine component temperature. These variables affect the two critical combustion parameters: ignition timing and combustion duration. If these two parameters can be controlled by appropriate settings of the operating variables, a good HCCI combustion scheme could be achieved. Therefore, the theoretical prediction of these two combustion parameters as a function of the key operating variables is necessary for development of HCCI combustion. This paper describes a stand-alone, single-zone and multi-zone combustion model which have been developed for the specific purpose of investigating HCCI combustion control. In the multi-zone model, temperature and composition in each zone were adjusted in order to study the effect of in-homogeneity which is critical to understanding ignition timing and combustion duration in real HCCI engines. The models simulated HCCI combustion using two fuels: hydrogen, (11 species, 23 reactions- from CHEMKIN library), and natural gas, (53 species, 325 reactions- from GRI mech). The capabilities of the two models to predict ignition timing, combustion duration and peak pressure were verified against experimental and simulation results of Fiveland et al [2, 11]. The models were then used to study the effect of different in-homogeneity levels of equivalence ratio, intake temperature and residual fraction. The single zone model could only predict ignition timing while the multi-zone model shows the capability to mimic realistic HCCI combustion phenomena. The study showed that some degree of in-homogeneity is critical to predicting performance of the homogeneous charge compression ignition engine. Further, stratification of equivalence ratio was relatively ineffective at changing combustion while stratification of mixture temperature was very effective. Stratification of the residual fraction proved to be the most promising method of controlling combustion parameters and the mechanism was primarily thermal.

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Foltynowicz, Aleksandra, Florian M. Schmidt, Weiguang Ma e Ove Axner. "Fiber-Laser-Based NICE-OHMS for Ultra-sensitive Trace Species Detection". In Laser Applications to Chemical, Security and Environmental Analysis. Washington, D.C.: OSA, 2008. http://dx.doi.org/10.1364/lacsea.2008.ltua5.

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