Search results for " taxonomic composition"

showing 2 items of 2 documents

Empirical Bayes improves assessments of diversity and similarity when overdispersion prevails in taxonomic counts with no covariates

2019

Abstract The assessment of diversity and similarity is relevant in monitoring the status of ecosystems. The respective indicators are based on the taxonomic composition of biological communities of interest, currently estimated through the proportions computed from sampling multivariate counts. In this work we present a novel method to estimate the taxonomic composition able to work even with a single sample and no covariates, when data are affected by overdispersion. The presence of overdispersion in taxonomic counts may be the result of significant environmental factors which are often unobservable but influence communities. Following the empirical Bayes approach, we combine a Bayesian mo…

0106 biological sciencesMultivariate statisticsBiological dataEmpirical Bayesian estimationEcologyTaxonomic compositionGeneral Decision SciencesEnvironmental monitoring010501 environmental sciencesBayesian inference010603 evolutionary biology01 natural sciencesBiodiversity assessment; Dirichlet-Multinomial model; Empirical Bayesian estimation; Environmental monitoring; Taxonomic compositionMarginal likelihoodBayes' theoremOverdispersionStatisticsTaxonomic rankDirichlet-Multinomial modelBiodiversity assessmentEcology Evolution Behavior and Systematics0105 earth and related environmental sciencesEmpirical Bayes methodMathematics
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Diatoms from thermal-sulphur waters of “Fiume Caldo” (North-western Sicily).

2007

The present study describes the taxonomic composition, richness and seasonal dynamics of the diatom community from thermal-sulphur waters of "Fiume Caldo" (Northwestern Sicily). The diatom flora of these waters consists of 64 taxa, showing similarities with thermal diatom communities from different geographical areas. Among the recorded taxa, Diadesmis confervacea Kütz. is a new record for Sicily. Seasonal changes in assemblage composition and richness have been recorded; the highest diversity values were observed during winter and spring, while during summer the diatom community consisted of a limited number of organisms whereas blue-green algae were quantitatively dominant. Inside the stu…

Sicily thermal-sulphur waters diatoms taxonomic composition seasonal dynamicsSettore BIO/02 - Botanica Sistematica
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