13 research outputs found

    Near-ground Effect of Height on Pollen Exposure

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    The effect of height on pollen concentration is not well documented and little is known about the near-ground vertical profile of airborne pollen. This is important as most measuring stations are on roofs, but patient exposure is at ground level. Our study used a big data approach to estimate the near-ground vertical profile of pollen concentrations based on a global study of paired stations located at different heights. We analyzed paired sampling stations located at different heights between 1.5 and 50m above ground level (AGL). This provided pollen data from 59 Hirst-type volumetric traps from 25 different areas, mainly in Europe, but also covering North America and Australia, resulting in about 2,000,000 daily pollen concentrations analyzed. The daily ratio of the amounts of pollen from different heights per location was used, and the values of the lower station were divided by the higher station. The lower station of paired traps recorded more pollen than the higher trap. However, while the effect of height on pollen concentration was clear, it was also limited (average ratio 1.3, range 0.7–2.2). The standard deviation of the pollen ratio was highly variable when the lower station was located close to the ground level (below 10m AGL). We show that pollen concentrations measured at >10m are representative for background near-ground levels

    Austroparmelina, a new Australasian lineage in parmelioid lichens (Parmeliaceae, Ascomycota)

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    Parmelioid lichens form the largest monophyletic group within the Parmeliaceae, a family distributed worldwide. The genus Parmelina was described by Hale (1976a) accommodating species from both hemispheres. We have employed parsimony, Bayesian and maximum likelihood analyses of a combined data set of nu ITS, LSU and mt SSU rDNA sequences to (1) test the monophyly of Parmelina and (2) to elucidate the generic status and phylogenetic position of the Australasian species. Twenty-one new sequences were generated in this study. Our results provide evidence that Parmelina is polyphyletic and the species fall into two major well-supported groups (Groups I and II). The Australasian species of Parmelina and two species of Canoparmelia (C. pruinata and C. macrospora) form Group I, which is nested within the parmotremoid genera of Parmeliaceae, Parmelina species from the northern hemisphere including those from western North America and the Mediterranean basin form a monophyletic group (Group II), which is sister to the East Asian temperate genus Myelochroa. Morphological and chemical features were reevaluated considering this observed phylogeny. Some morphological features like lobe morphology, several traits in the excipulum and geography are useful in characterizing the monophyletic lineage of the Australasian Parmelina/Canoparmelina species. This lineage is described as the new genus Austroparmelina. Thirteen new combinations in the new genus are proposed

    Data from: Phylogenetic generic classification of parmelioid lichens (Parmeliaceae, Ascomycota) based on molecular, morphological and chemical evidence

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    Parmelioid lichens are a diverse and ubiquitous group of foliose lichens. Generic delimitation in parmelioid lichens has been in a state of flux since the late 1960s with the segregation of the large, heterogeneous genus Parmelia into numerous smaller genera. Recent molecular phylogenetic studies have demonstrated that some of these new genera were monophyletic, some were not, and others, previously believed to be unrelated, fell within single monophyletic groups, indicating the need for a revision of the generic delimitations. This study aims to give an overview of current knowledge of the major clades of all parmelioid lichens. For this, we assembled a dataset of 762 specimens, including 31 of 33 currently accepted parmelioid genera (and 63 of 84 accepted genera of Parmeliaceae). We performed maximum likelihood and Bayesian analyses of combined datasets including two, three and four loci. Based on these phylogenies and the correlation of morphological and chemical characters that characterize monophyletic groups, we accept 27 genera within nine main clades. We re-circumscribe several genera and reduce Parmelaria to synonymy with Parmotrema. Emodomelanelia Divakar & A. Crespo is described as a new genus (type: E. masonii). Nipponoparmelia (Kurok.) K.H. Moon, Y. Ohmura & Kashiw. ex A. Crespo & al. is elevated to generic rank and 15 new combinations are proposed (in the genera Flavoparmelia, Parmotrema, Myelochroa, Melanelixia and Nipponoparmelia). A short discussion of the accepted genera is provided and remaining challenges and areas requiring additional taxon sampling are identified

    Data from: Phylogenetic generic classification of parmelioid lichens (Parmeliaceae, Ascomycota) based on molecular, morphological and chemical evidence

    No full text
    Parmelioid lichens are a diverse and ubiquitous group of foliose lichens. Generic delimitation in parmelioid lichens has been in a state of flux since the late 1960s with the segregation of the large, heterogeneous genus Parmelia into numerous smaller genera. Recent molecular phylogenetic studies have demonstrated that some of these new genera were monophyletic, some were not, and others, previously believed to be unrelated, fell within single monophyletic groups, indicating the need for a revision of the generic delimitations. This study aims to give an overview of current knowledge of the major clades of all parmelioid lichens. For this, we assembled a dataset of 762 specimens, including 31 of 33 currently accepted parmelioid genera (and 63 of 84 accepted genera of Parmeliaceae). We performed maximum likelihood and Bayesian analyses of combined datasets including two, three and four loci. Based on these phylogenies and the correlation of morphological and chemical characters that characterize monophyletic groups, we accept 27 genera within nine main clades. We re-circumscribe several genera and reduce Parmelaria to synonymy with Parmotrema. Emodomelanelia Divakar & A. Crespo is described as a new genus (type: E. masonii). Nipponoparmelia (Kurok.) K.H. Moon, Y. Ohmura & Kashiw. ex A. Crespo & al. is elevated to generic rank and 15 new combinations are proposed (in the genera Flavoparmelia, Parmotrema, Myelochroa, Melanelixia and Nipponoparmelia). A short discussion of the accepted genera is provided and remaining challenges and areas requiring additional taxon sampling are identified

    Phylogenetic generic classification of parmelioid lichens (Parmeliaceae,Ascomycota) based on molecular, morphological and chemical evidence.

    No full text
    Parmelioid lichens are a diverse and ubiquitous group of foliose lichens. Generic delimitation in parmelioid lichens has been in a state of flux since the late 1960s with the segregation of the large, heterogeneous genus Parmelia into numerous smaller genera. Recent molecular phylogenetic studies have demonstrated that some of these new genera were monophyletic, some were not, and others, previously believed to be unrelated, fell within single monophyletic groups, indicating the need for a revision of the generic delimitations. This study aims to give an overview of current knowledge of the major clades of all parmelioid lichens. For this, we assembled a dataset of 762 specimens, including 31 of 33 currently accepted parmelioid genera (and 63 of 84 accepted genera of Parmeliaceae). We performed maximum likelihood and Bayesian analyses of combined datasets including two, three and four loci. Based on these phylogenies and the correlation of morphological and chemical characters that characterize monophyletic groups, we accept 27 genera within nine main clades. We re-circumscribe several genera and reduce Parmelaria to synonymy with Parmotrema. Emodomelanelia Divakar & A. Crespo is described as a new genus (type: E. masonii). Nipponoparmelia (Kurok.) K.H. Moon, Y. Ohmura & Kashiw. ex A. Crespo & al. is elevated to generic rank and 15 new combinations are proposed (in the genera Flavoparmelia, Parmotrema, Myelochroa, Melanelixia and Nipponoparmelia). A short discussion of the accepted genera is provided and remaining challenges and areas requiring additional taxon sampling are identified

    Near-ground effect of height on pollen exposure

    No full text
    The effect of height on pollen concentration is not well documented and little is known about the near-ground vertical profile of airborne pollen. This is important as most measuring stations are on roofs, but patient exposure is at ground level. Our study used a big data approach to estimate the near-ground vertical profile of pollen concentrations based on a global study of paired stations located at different heights. We analyzed paired sampling stations located at different heights between 1.5 and 50 m above ground level (AGL). This provided pollen data from 59 Hirst-type volumetric traps from 25 different areas, mainly in Europe, but also covering North America and Australia, resulting in about 2,000,000 daily pollen concentrations analyzed. The daily ratio of the amounts of pollen from different heights per location was used, and the values of the lower station were divided by the higher station. The lower station of paired traps recorded more pollen than the higher trap. However, while the effect of height on pollen concentration was clear, it was also limited (average ratio 1.3, range 0.7–2.2). The standard deviation of the pollen ratio was highly variable when the lower station was located close to the ground level (below 10 m AGL). We show that pollen concentrations measured at >10 m are representative for background near-ground levels

    Effect of Height on Pollen Sampling in Relation to Pollen Exposure at Ground Level

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    Pollen monitoring networks around the world are mainly based on rooftop-located stations on buildings. Thus, measured airborne pollen levels could be different from ground level, where most allergic individual reside. Until now, the effects of height of sampling on pollen concentration are not well documented. The aim of this meta-analysis was to analyse these effects using a large number of twin sampling stations. Pollen data from 45 twin-stations Hirst-type volumetric spore traps were analyzed, with a maximum distance of 5km between the twin traps, from 25 different locations. To compare the effect of height, the mean of the daily ratio of the amounts of pollen registrered at different heights was used. The values of the lowest station were divided by the higher station. Stations between 1.5m and 50 agl were considered. The results showed that the traps at lower height registered generally higher pollen concentration (average pollen ratio higher than 1), although the behaviour of the ratio differed per pollen type. For instance, both Poaceae and Betula showed that as the height differenc eincreased, the pollen ratio was higher up to a certain height difference when the ratio stabilizes (around 1.5). On the other hand, the standard deviation of the pollen ratio was greater for the traps closer to ground level. Therefore the height difference is a factor which explains the pollen ratio in conjunction with other variables such as the minimum height of the lower trap or the distance between the spore traps. These findings are highly relevant to clinical practice, as the relationship between pollen exposure at ground level and monitored airborne pollen concentrations at roof-top elvel are determined. Thus, the optimal pollen monitoring height could be optimized based on these result
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