Showing papers on "Lichen published in 1992"
1 May 1992
TL;DR: 128 species in 45 genera of sorediate and isidiate, crustose, corticolous lichens are recorded from Norway, and a discussion of their distribution in Norway is supported by maps for a number of taxa.
Abstract: Abstract 128 species in 45 genera of sorediate and isidiate, crustose, corticolous lichens are recorded from Norway. Accounts of their morphology, chemistry, and substratum preferences are presented, and a discussion of their distribution in Norway is supported by maps for a number of taxa. With few exceptions, the taxa can be distinguished on thallus characters alone. Several taxa, especially those with brown or blue-pigmented soralia, have soredia with a distinct cortex. New species are: Buellia arborea Coppins & Tønsb. (from Norway and Scotland), Fuscidea arboricola Coppins & Tønsb. (from Norway, Sweden, and Scotland), F. pusilla Tønsb. (from Norway, Sweden, and Scotland), Lecanora flavoleprosa Tønsb. (from Norway and Austria), L. flavopunctata Tønsb. (from Norway and Sweden), L. norvegica Tønsb. (from Norway), Lecidea gyrophorica Tønsb. (syn. L. epizanthoidiza auct., non Nyl.), L. praetermissa Tønsb. (from Norway and Sweden), L. subcinnabarina Tønsb. (from Norway), L. vacciniicola Tønsb. (from Norway, Sweden, and Spain), Lecidella subviridis Tønsb. (from Norway and Sweden), Lepraria elobata Tønsb. (from Norway), L. jackii Tønsb. (from Norway), L. obtusatica Tønsb. (from Norway), L. umbricola Tønsb. (from Norway, England, and Scotland), Micarea coppinsii Tønsb. (from Norway and Scotland), Rinodinaflavosoralifera Tønsb. (from Norway), R. disjuncta Sheard & Tønsb. (from Norway and the pacific coast of U.S.A. and Canada), and Schaereria corticola Muhr & Tønsb. (from Norway, Sweden and Scotland). Ochrolechia androgyna s. lat. is shown to comprise at least four distinct species. New combinations are: Cliostomum leprosum (Räsänen) Holien & Tønsb., Lepraria rigidula (B. de Lesd.) Tønsb., Mycoblastus caesius (Coppins & P. James) Tønsb., Placynthiella dasaea (Stirton) Tønsb., and Ropalospora viridis (Tønsb.) Tønsb. Lecidea turgidula var. pulveracea Fr. is raised to specific level with the new name Lecidea leprarioides Tønsb. Mycoblastus sterilis Coppins & P. James is reduced to synonymy with M. fucatus Stirton. Pertusaria borealis is new to Europe. Halecania viridescens, Lecanora farinaria, Lepraria caesioalba Laundon ined., L. eburnea Laundon ined., Megalospora tuberculosa, Opegrapha multipuncta, and Scoliciosporum gallurae are new to Scandinavia. Mycoblastus caesius, Lecidella elaeochroma “f. soralifera”, L. flavosorediata, Micarea granulans (saxicolous, not treated), Opegrapha sorediifera, and Rinodina degeliana are new to Norway. In some cases, Poelt’s species pair concept can be applied to this group of lichens. Additional secondary substances, not occurring in the primary species, sometimes occur in the soralia of the secondary species. In this case, presence of the additional substance cannot be regarded as an independent taxonomic character, and the species pair concept is still useful. However, morphologically indistinguishable specimens with different chemistry may represent different secondary species. The term consoredia is introduced to denote diaspores composed of aggregated soredia.
305 citations
1 Jan 1992
234 citations
1 Apr 1992
154 citations
TL;DR: A lichen-specific secondary pathway was consistently induced in a lichen fungus (Cladonia grayi) grown in the absence of the alga and secondary productivity was comparable to that of some nonlichen fungi.
106 citations
TL;DR: This study uses molecular information to investigate if R. capensis should be treated as a species-pair or not, and investigates whether the randomly amplified polymorphic DNA (RAPD) method would be a suitable procedure in population studies of lichens.
Abstract: Morphological, anatomical, chemical and ecological evidence show that the South African lichen Roccellina capensis (Nyl. ex Stizenb.) Tehler has developed a dispersal strategy with either sexually dispersed individuals, or vegetatively dispersed, sorediate individuals, hence a putative species-pair. The concept ‘species-pair’ is well-known and widely used in lichenology. It refers to closely related, morphologically indistinguishable lichens that differ from each other by their dispersal strategies only. The so-called ‘ primary species ’ produces fruiting bodies and sexual spores, while its counterpart, the ‘ secondary species ’ is vegetatively dispersed by soredia, isidia or fragmentation. Our study uses molecular information to investigate if R. capensis should be treated as a species-pair or not. The internal transcribed spacer (ITS) of the nuclear ribosomal DNA was sequenced for 17 specimens of R. capensis in order to test if sexual and asexual (sorediate) specimens would group into two distinct, monophyletic groups. Such grouping would support their recognition as separate taxa in a species-pair. We also investigated whether the randomly amplified polymorphic DNA (RAPD) method would be a suitable procedure in population studies of lichens. The analysis of the ITS region produced a single most parsimonious tree. The sexual and asexual specimens were grouped according to their geographical distribution, rather than according to their dispersal strategy. This result clearly shows that the sexual and asexual specimens of R. capensis do not represent a species-pair. The RAPD data set produced an almost completely unresolved tree due to several homoplasious characters, possibly a result of algal contamination.
100 citations
TL;DR: Though the levels of these compounds were much lower in the Windmill Islands lichens than in maritime Antarctic species, their content with respect to water content was well above that at which cold acclimated plants accumulate these compounds and which provide cryoprotection in vitro.
Abstract: Ethanol extractable polyols and sugars from the dominant cryptogams of the Windmill Islands, Wilkes Land, East Antarctica, were characterized and quantified by gas liquid chromatography. Arabitol, ribitol and mannitol were the major low molecular weight carbohydrates extracted from all eight species of lichen analysed. Total extractable carbohydrate levels (20–60 mg g−1 dry weight) were comparable to those for temperate lichens. Extracts of four common bryophyte species were dominated by sucrose, glucose and fructose; little polyhydric alcohol was detected except in the liverwort Cephaloziella exiliflora which contained a substantial proportion of mannitol. Total carbohydrate levels in the bryophytes (9–60 mg g−1 dry weight) were comparable to those in lichens. The compositions of eight species of algae varied considerably. Prasiola crispa, Desmococcus vulgaris and Schizogonium murale possessed sorbitol as their main constituent and had extractable carbohydrate contents comparable to those found in bryophytes on a dry weight or chlorophyll a content basis. The one snow alga with comparable carbohydrate levels, Mesotaenium berggrenii, contained sucrose, glucose, glycerol and a number of unidentified compounds. The remaining four species (Oscillatoria sp., Chloromonas sp.1 and Chlorosarcina sp. 2 and Chlamydomonas pseudopulsatilla) did not accumulate comparable levels of sugars and polyols. Though the levels of these compounds were much lower in the Windmill Islands lichens than in maritime Antarctic species, their content with respect to water content (0.7–7 molal) was well above that at which cold acclimated plants accumulate these compounds (c. 100–500 millimolal), and which provide cryoprotection in vitro. In the case of the bryophytes and algae, however, the in vivo content was generally < 100 millimolal.
87 citations
9 Jul 1992
TL;DR: Bryophytes and lichens are sensitive indicators of environmental conditions and are commonly used for biomonitoring and ecological studies.
Abstract: Abstract This volume presents a synthesis of new information about the responses of bryophytes and lichens to changing environmental conditions, particularly those brought about by human activities. Bryophytes and lichens are often treated independently, but as they commonly exist in association they are here described together. Both groups are sensitive indicators of environmental conditions; at various times the use of one group or the other has been recommended to indicate the presence of particular mineral deposits (geological prospecting), soil and site conditions (forestry), level of atmosphere and aquatic pollutants (biomonitoring), ages of rock surfaces (lichenometry), and historical continuity of forests cover (bioindication). Topics covered in this book include physiology, distribution, ecological function, and response to pollution and land management of these organisms.
63 citations
TL;DR: In this article, the authors measured 137C activity in Xanthoria parietina and showed that the activity concentration could be expressed both on a dry weight and on a contour surface area basis.
60 citations
9 Jul 1992
TL;DR: Ecological classifications of bryophytes and lichens classify plants into various groups based on common characters, responses to the environment, growth-forms, life-forms, and life-history strategies.
Abstract: Abstract Attempts to classify plants using common characters or responses to the environment are as old as botany (cf. Barkman 1988). Apart from taxonomical classifications, plants have been grouped into chorological types, sociological and ecological species groups, growth-forms, life-forms, and life-history strategies. Such classifications are useful for making comparisons of the ecology of species and communities in different geographical regions (Smith 1982).
TL;DR: The lichen genus Relicina in Australasia and their relationship to species in other parts of the world is studied, as well as the composition and distribution of the 'Lobarion' in the forest of South-East Asia.
Abstract: List of contributors and participants D.J. Galloway: Biogeographical relationships of Pacific tropical lichen floras J.A. Elix: The lichen genus Relicina in Australasia C.W. Smith: Lichen conservation in Hawaii G.N. Stevens: The tropical Pacific species of Usnea and Ramalina and their relationship to species in other parts of the world P.W. Lambley: Lichens of Papua New Guinea H. Krog: Lichenological observations in low montane rainforests of eastern Tanzania E. Farkas: New and interesting records of Tanzanian foliicolous lichens I. Karnefelt: Evolutionary rates in the Teloscistaceae L. Arvidsson: Lichenological studies in Ecuador H.J.M. Sipman: Notes on the lichen flora of the Guianas, a neotropical lowland area M.P. Marcelli: Aspects of the foliose lichen flora of the southern-central coast of Sao Paulo State, Brazil S.C. Tucker, S.W. Matthews, & R.L. Chapman: Ultrastructure of subtropical crustose lichens L. Arvidsson: On the importance of botanical gardens for lichens in the Asian tropics J.C. Wei & Y.M. Jiang: Some foliicolous lichens in Xishuangbanna, China P.A. Wolseley: Observations on the composition and distribution of the 'Lobarion' in the forest of South-East Asia M. Wedin: Spore ontogeny of Sphaerophorus diplotypus and S. fragilis A. Aptroot: Tropical pyrenocarpous lichens, a phylogenetic approach T.D.V. Swinscow: Epilogue Index.
TL;DR: Based on field studies and herbarium research, 46 species of lichens and lichenicolous fungi are reported new to British Columbia as discussed by the authors, including 15 new species for Canada for the first time.
Abstract: Based on field studies and herbarium research, 46 species of lichens and lichenicolous fungi are reported new to British Columbia. The following 15 species are documented for Canada for the first time: Agonimia tristicula, Catapyrenium daedaleum, Cladonia luteoalba, Collema auriforme, Dactylospora lobariella, Fulgensia desertorum, Massalongia microphylliza, Pannaria ahlneri, Peltula euploca, Physcia callosa, Psora montana, Sticta wrightii, Usnea wirthii, Vester- grenopsis elaeina, and Xanthoparmelia planilobata. An additional nine species are new to North America north ofMexico: Acroscyphus sphaerophoroides, Biatoropsis usnearum, Hawksworthiana peltigericola, Leptogium brebissonii, L. schraderi, Lichenochora thallina, Scutula miliaris, Sphae- rellothecium araneosum, and Trapelia corticola.
TL;DR: A survey of Breckland grass heaths showed that the characteristic plant communities were found on rabbit-grazed but not sheep- grazed sites, and sites which had been rotovated had shorter grass, a higher abundance of lichens and annual plants, less organic matter and greater rabbit activity than control plots.
Abstract: 1. Sites of previous vegetation quadrats were revisited and reanalysed. There was a trend from characteristic Breckland communities with an abundance of lichens, winter annuals and cushion-forming mosses towards rank grassland. 2. A survey of Breckland grass heaths showed that the characteristic plant communities were found on rabbit-grazed but not sheep-grazed sites. 3. Sites which had been rotovated had shorter grass, a higher abundance of lichens and annual plants, less organic matter and greater rabbit activity than control plots. 4. Encouraging rabbits and disturbing the soil are essential to maintain these heaths.
TL;DR: Four zones are distinguished within the Central Namib fog desert lichen field, each dominated by a growth form indicating various influences of different climatic, geomorphic or biogenic parameters.
Abstract: Number, geographic location, extent and characteristics of lichen fields were recorded within the Central Namib fog desert. Their occurrence is restricted to stable surfaces in the near coastal belt, while percentage cover changes with exposure, elevation and distance from the coastline. Maximum coverage of 70% was found at a distance of 5 km from the coast near Wlotzkas Baken. The highest biomass rate of 400 mg/m2 was measured here at a distance of 1 km from the coast, where Teloschistes capensis appears as cushion growth type. Distribution patterns on hills, riverbeds and polygon structures are described. In general, fruticose and foliose lichens dominate on SW-exposed, ocean-facing habitats. Crustose species dominate on NE-E-exposed plots.
TL;DR: Lichens were held in high regard by medicinal practitioners in medieval times and the use has persisted into modern times and is used in the Ayurvedic and Unani systems of medicines.
TL;DR: In the Upper Mazaruni District, Guyana, a lichen exploration yielded 273 species, of which 179 were found for the first time in the Guianas and 13 were as yet undescribed as mentioned in this paper.
Abstract: Lichen exploration of the Upper Mazaruni District, Guyana yielded 273 species, of which 179 were found for the first time in the Guianas and 13 were as yet undescribed. A list of all taxa encountered is presented, with indications of habitat and distribution in the investigated area as well as first descriptions for the following 7 species: Buellia aptrootii , Byssoloma farkasii , Myriotrema guianense , M . neofrondosum , M . subdactyliferum , Ocellularia astrolucens , and Thelotrema albomaculatum . Mazosia bambusae is recorded for the first time from the Neotropics. The richest areas for lichens appear to be the rocky tablelands with scrub vegetation on top of the lower mountains. The slopes of Mount Roraima are of special interest because they support some montane species which are unlikely to be found elsewhere in the Guianas; otherwise they are less rich in lichens, probably because of the high humidity, which favours bryophyte growth.
9 Jul 1992
TL;DR: The vanishing tropical rain forest is rapidly being destroyed, and all tropical rain forests will be destroyed by the middle of the next century.
Abstract: Abstract Tropical forests make up about half of the world ‘s closed forests, yet are rapidly being destroyed. By the end of the 1970s, the Food and Agriculture Organization (FAQ) of the United Nations estimated that about 46 per cent of the tropical forests were already gone and the remainder were disappearing at a rate of over 2 per cent per year, either by clear-cutting or by shifting cultivation (Raven 1988). The conclusion was that all tropical rain forests would be destroyed by the middle of the next century, while the seasonal forests, occurring in regions with more pronounced fluctuations in rainfall and usually more suitable for human inhabitation, would already have disappeared long before.
TL;DR: A great variation in values was observed when comparing contamination in all the habitats investigated during the same collecting season, and a gradual decrease was detected that depended on the habitat and the collected species.
Abstract: Cesium-137 content in lichens and mosses from northern Greece was measured for regular periods of time during the 5 years following the Chernobyl reactor accident. A clear increase of the cesium interception was observed for about 2 years after the accident. Later a gradual decrease was detected that depended on the habitat and the collected species. A great variation in values was observed when comparing contamination in all the habitats investigated during the same collecting season. Key words: 137Cs, lichens, mosses, radionuclides, Chernobyl.
TL;DR: In the present study only one lichen species, Hypogymnia physodes (L.) Nyl.
Abstract: Epiphytic lichens have long been considered to be reliable bioindicators of air pollution. In the present study only one lichen species, Hypogymnia physodes(L.) Nyl., was chosen; this species is very often used for biomonitoring in Europe. Total mercury and methylmercury were determined in lichens taken from various polluted and unpolluted locations in Slovenia, including a mercury mining area around Idrija. Additionally, total gaseous mercury in air was also determined at several sampling points.
TL;DR: Despite numerous investigations on the re-establishment of epiphytic cryptogams, especially lichens, after forest fires, very little is known about the recolonization of burnt rocks by lithobiontic fungi.
Abstract: Despite numerous investigations on the re-establishment of epiphytic cryptogams, especially lichens, after forest fires, very little is known about the recolonization of burnt rocks by lithobiontic...
Journal Article•
TL;DR: In this article, the authors determined the extent to which the relatively sparse lichen flora on the trunks of Scots pines (Pinus sylvestris L.) can serve as an indicator of air purity.
Abstract: The purpose was to determine the extent to which the relatively sparse lichen flora on the trunks of Scots pines (Pinus sylvestris L.) can serve as an indicator of air purity. The percentage cover and condition of the lichens were recorded in sample plots from which lichens (Hypogymnia physodes) and pine needles were collected for chemical analysis. Clear differences in pollution tolerance were found between the species, Pla tismatia glauca and H. tubulosa being the most sensitive of the macro lichens and H. physodes and Parmeliopsis ambigua the most tolerant. With decreasing distance from the city centre the numbers of macrolichen species and their size and percentage cover diminished, changes in their external appearance became more marked and the concentrations of im purities in the lichens and pine needles increased. Pendulous lichens of the genus Bryoria occurred on fairly polluted plots, but their maximum lengths remained small. No actual 'lichen desert' could be discerned, however. The interaction of air pollutants with other environmental factors is discussed.
1 Jan 1992
TL;DR: The importance of nonvascular photosynthetic plants (primarily algae, lichens, and mosses) in arid and semi-arid ecosystems is discussed in this article, where the authors show that they can perform critical functions of protecting the soil from erosion, aiding in water infiltration, augmenting sites for seed germination and increasing the soil's supply of nutrients.
Abstract: Cryptogamic crusts,† consisting of nonvascular photosynthetic plants (primarily algae, lichens, and mosses) that live on the soil surface, are important elements of arid and semi-arid ecosystems worldwide (Cameron and Fuller, 1960; Shtina and Bolyshev, 1963; Snyder and Wullstein, 1973; Johansen et al., 1984; Harper and Marble, 1988). Because of a deficiency of available moisture, arid and semi-arid regions of the world are characterized by a lack of significant vegetative cover. Cryptogamic crusts, which often occur alone and mixed with grasses in the interspaces between woody plants, can perform critical functions of protecting the soil from erosion (Bailey et al., 1973), aiding in water infiltration, augmenting sites for seed germination (St. Clair et al., 1984; Harper and Marble, 1988), and increasing the soil’s supply of nutrients (Shields and Durrell, 1964; Loope and Gifford, 1972; Rychert and Skujins, 1974; Brotherson and Rushforth, 1983; Jeffries, 1989; Beymer and Klopatek, 1991).
TL;DR: About 60-80% of the mainland and 5-30% of most island winter lichen ranges are presently estimated to be in good to excellent ecological condition, with wildfires having had the greatest impact on lichen range depletion on the mainland.
Abstract: Populations of reindeer (Rangifer tarandus) have fluctated greatly since their introduction to Alaska in 1891. In the 1930s, reported numbers exceeded 600 000. Presently, 38 000 reindeer graze 6.2 million ha of rangeland and woodland in Western Alaska (from 66°54'N to 52°07'N latitude). Condition of winter range producing fruticose lichens (Cladina rangiferina, Cladina arbuscula, Cladina stellaris, Cetraria cucullata, Cetraria islandica) is of major concern. Monitoring programs have been established for vegetation, fire, reindeer and wildlife. Reindeer have overgrazed lichen resources on some Bering Sea Islands. Wildfires have had the greatest impact on lichen range depletion on the mainland. Overgrazing has been a problem in localized areas. Moose (Alces alces) and muskox (Ovibos moschatus) rarely contribute to major lichen depletion. 60-80% of the mainland and 5-30% of most island winter lichen ranges are presently estimated to be in good to excellent ecological condition. Procedures for assessing condition of the lichen ranges are being further refined.
TL;DR: In this article, the aromatic compounds of more than 400 specimens of 33 species of the lichen genus Umbilicaria have been investigated by HPLC and the new depside crustinic acid has been found.
Abstract: Abstract The aromatic compounds of more than 400 specimens of 33 species of the lichen genus Umbilicaria have been investigated by HPLC. Additionally to gyrophoric, hiascic, lecanoric, ovoic and umbilicaric acids, atranorin, norstictic and stictic acids, the new depside crustinic acid has been found. Structure elucidation of crustinic acid was made by means of HPLC cochromatography, NMR , UV and mass spectrometry. Now the secondary product patterns of Umbilicaria species are discussed and their significance for systematic purposes is shown.
TL;DR: The decline of lichens throughout Europe and elsewhere over the past two centuries is mainly attributable to increases in air pollution in general, and to sulphur dioxide in particular as discussed by the authors, and the destructive role of other atmospheric pollutants has either been masked by the overriding effects of sulphurioxide or insufficiently appreciated due to the inadequacy of monitoring equipment.
Abstract: The decline of lichens throughout Europe and elsewhere over the past two centuries is mainly attributable to increases in air pollution in general, and to sulphur dioxide in particular. The destructive role of other atmospheric pollutants, and indeed other factors, has either been masked by the overriding effects of sulphur dioxide or insufficiently appreciated due to the inadequacy of monitoring equipment. Research has shown that qualitative as well as quantitative changes in air pollution due to shifts in energy and transportation policies on the one hand and economic and legislative factors on the other over the past twenty years are having significant effects on lichen floras. The versatility of lichens in highlightning not only the existence but also the rise and fall in levels of these new pollution regimes over wide geographical areas is demonstrated by reference to the British Isles.
9 Jul 1992
TL;DR: Lichen decline due to air pollution is a widespread phenomenon. Air pollution affects lichen distribution and abundance. The decline is correlated with sulphur dioxide levels.
Abstract: Abstract The decline of lichen floras under the impact of air pollution has been a worldwide phenomenon. So sensational is the decline that a Scandinavian worker coined the term ‘lichen desert ‘ to describe the centre of towns where trees are devoid of foliose and fruticose lichens (Sernander 1926). In the UK the degree of impoverishment was shown to correspond closely with levels of sulphur dioxide, a correlation made possible using the results of a national network of nearly 1300 air pollution gauges (Clifton 1969). Though it was not fully appreciated at the time, stable SO2 emission rates aided the calibration of semi-quantitative biological scales for estimating levels of air pollution that were constructed in the late 1960s (Gilbert 1970a; Hawksworth and Rose 1970). This was the period when ecological interactions between lichens and air pollution were most vigorously investigated. Species were listed in order of their sensitivity, the effect of environmental variables such as pH, nutrient availability, and microclimate were investigated, and a number of other air pollutants were screened to determine whether they too were having any effect. The only ones convincingly shown to be influencing lichen distribution were point source emissions of flourides, which are harmful (Martin and Jacquard 1968; Gilbert 1973b), and alkaline dust which is able to counteract SO2 producing small oases of lichen-rich vegetation (Gilbert 1976).
TL;DR: Brown et al. as discussed by the authors showed that fresh Antarctic mosses treated with hydrochloric acid could retain Na, P, Ca and K after leaching with concentrated solution of these elements.
Abstract: Retention of mineral elements in precipitation by mosses and lichens involving ion exchange and chelation mechanisms is a source of nutrients for these biota growing on rocks and nutrient poor soils (Brown 1987, Crittenden 1989). In qualitative work not involving nitrogen (N) Allen et al. (1967) demonstrated that fresh Antarctic mosses treated with hydrochloric acid could retain Na, P, Ca and K after leaching with concentrated solution of these elements. Ahumic fellfield soils are widespread in Antarctica and support sparse plant growth. This short note reports the results of work designed to show that fellfield soils and plants may obtain most of their N from atmospheric precipitation.