Abstract: Export Date: 29 March 2012/Source: Scopus/
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Keywords: NULL, ASCI, DOLERITE, FLORA OF AUSTRALIA, LICHENS, NULL
Abstract: The new genus, Cameronia Kantvilas, is described and illustrated. It is characterized by a crustose thallus, a chlorococcalean photobiont, deeply immersed perithecioid ascomata, four-spored asci with an intensely hemiamyloid outer wall and non-amyloid, well-developed tholus, and hyaline, muriform ascospores. The taxonomic position of the new genus is uncertain although a relationship with the Ostropomycetidae is likely. Two species, both endemic to the highlands of Tasmania, are described: C. pertusarioides Kantvilas, which is one of the most common lichens on dolerite in alpine Tasmania, and C. tecta Kantvilas, which is confined to metamorphosed sediments.
Notes: New genus: Cameronia Kantvilas; new species: Cameronia pertusarioides Kantvilas and C. tecta Kantvilas
URL: http://dx.doi.org/10.1017/S0024282911000569
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Abstract: Acarospora gallica from Europe and Asia is revised and a neotype is designated. Acarospora hungarica is proposed as a synonym of A. gallica. The anamorphic stage is reported for the first time from the species.
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Keywords: BIODIVERSITY, TAXONOMY
Abstract: Three species and one genus are reported new for South America (all are from Ecuador): Acarospora americana, Caeruleum heppii, and Polysporina simplex. Acarospora catamarcae and A. thelomma are verified as distinct species occurring in Argentina. Acarospora punae is placed in synonymy with A. thelomma and lectotypes are designated for both names. Acarospora sparsiuscula is also verified as a distinct species, originally described from Argentina and here reported from the Galapagos Islands in Ecuador. A total of twenty-seven species of Acarosporaceae are recognized as occurring in South America in this ongoing taxonomic series.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=276114
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Keywords: BIODIVERSITY/ FLORISTICS/ PARASITES/
Abstract: One hundred and eighty-seven lichenicolous fungi and lichenicolous lichens are reported from California. Abrothallus acetabuli and Intralichen lichenicola are reported new for North America and California. Sclerococcum montagnei is reported new for California. A strict definition of lichenicolous lichens as non-lichenized juvenile parasites that develop an independent lichenized thallus is used and 19 species are reported for California.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=290237
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Abstract: The composition of low-molecular biologically active metabolites typical of microscopic fungi has been studied in blastemas of fruticose lichens of the genera Cladonia, Cetraria, Evernia, Bryoria, and Usnes. The enzyme immunoassay method showed the presence of sterigmatocystin, emodin, mycophenolic acid, citrinin, alternariol, and diacetoxyscirpenol, which occurred regularly and, in most cases, at a frequency of 55 to 100%. The highest levels of accumulation were 0. 001-0. 003% for emodin, 0. 0002% for alternariol and citrinin, 0. 0001% for sterigmatocystin and mycophenolic acid, and 0. 00005% of the weight of air-dry material for diacetoxyscirpenol. Other metabolites (cyclopiazonic acid, ergot alkaloids, ochratoxin A, PR toxin, deoxynivalenol, zearalenone, and fumonisins) were detected in these lichens less frequently (sometimes only upon the expansion of the territory of sampling), and their content was no more than 0. 00005%. The peculiarities of the component composition and the levels of accumulation of fungal metabolites in lichens of different taxonomic affiliation were discussed. © 2012 Pleiades Publishing, Ltd.
URL: http://dx.doi.org/10.1134/S0003683812010085
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Keywords: ANTICANCER ACTIVITY/ ANTIMICROBIAL ACTIVITY/ ANTIOXIDANT ACTIVITY/ LICHENS
Abstract: The aim of this study is to investigatein vitroantioxidant, antimicrobial, and anticancer activity of the acetone extracts of the lichens Umbilicaria crustulosa, U. cylindrica, and U. polyphylla. Antioxidant activity was evaluated by 5 separate methods: free radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds, and determination of total flavonoid content. Of the lichens tested, U. polyphyllahad largest free radical scavenging activity (72.79% inhibition at a concentration of 1 mg/mL), which was similar as standard antioxidants in the same concentration. Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. Total content of phenol and flavonoid in extracts was determined as pyrocatechol equivalent, and as rutin equivalent, respectively. The strong relationships between total phenolic and flavonoid contents and the antioxidant effect of tested extracts were observed. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. The most active was extract ofU. polyphyllawith minimum inhibitory concentration values ranging from 1.56 to 12.5 mg/mL. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method. All extracts were found to be strong anticancer activity toward both cell lines with IC50 values ranging from 28.45 to 97.82 ?g/mL. The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial, and anticancer effects. That suggests that lichens may be used as possible natural antioxidant, antimicrobial, and anticancer agents. © 2011 Institute of Food Technologists®.
URL: http://dx.doi.org/10.1111/j.1750-3841.2011.02459.x
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Abstract: A simple in-house pyrolysis chamber made of quartz material is described for the determination of total mercury content in a wide variety of organic-rich solid materials (plant, fish tissues and polymer based) by oxidative pyrolysis and cold vapour atomic absorption spectrometry (CVAAS). Oxidative pyrolysis was carried out by means of a Bunsen burner in the presence of an oxygen stream. Mercury liberated from the sample was collected in 0.1% KMnO4 trapping solution. Determination of mercury was achieved by CVAAS. Under optimal conditions, the limit of detection (LOD), calculated as the concentration of mercury yielding a signal equivalent to three times of the standard deviation of the blank value (3?), obtained for CVAAS in conjunction with the oxidative pyrolysis method was found to be 0.08 ng g. Flow injection inductively coupled plasma mass spectrometry (FI-ICPMS) was used to validate the developed method. The results obtained for several reference materials, such as mussel tissue (CE-278), tuna fish (CE-463), tuna fish (464), polyethylene (EC-681), plankton (CRM-414), lichen (CRM-482) and human hair (CRM-397), by the developed method agreed well with the certified values. These studies clearly demonstrate the capabilities of the pyrolysis set-up that can potentially be used for the rapid determination of total mercury in a wide variety of organic-rich matrices. © 2012 The Royal Society of Chemistry.
Notes: The new method was tested on lichen tissue.
URL: http://dx.doi.org/10.1039/c1ay05624g
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Keywords: 16S RRNA/ CHLOROPHYLL A/ CYANOBACTERIA/ MICROCOLEUS VAGINATUS/ SCYTONEMIN/ SOIL BIOCRUST
Abstract: The impact of 10 years of annual foot trampling on soil biocrusts was examined in replicated field experiments at three cold desert sites of the Colorado Plateau, USA. Trampling detrimentally impacted lichens and mosses, and the keystone cyanobacterium, Microcoleus vaginatus, resulting in increased soil erosion and reduced C and N concentrations in surface soils. Trampled biocrusts contained approximately half as much extractable DNA and 20-52% less chlorophyll a when compared with intact biocrusts at each site. Two of the three sites also showed a decline in scytonemin-containing, diazotrophic cyanobacteria in trampled biocrusts. 16S rRNA gene sequence and terminal restriction fragment length polymorphism (T-RFLP) analyses of soil bacteria from untrampled and trampled biocrusts demonstrated a reduced proportion (23-65% reduction) of M. vaginatus and other Cyanobacteria in trampled plots. In parallel, other soil bacterial species that are natural residents of biocrusts, specifically members of the Actinobacteria, Chloroflexi and Bacteroidetes, became more readily detected in trampled than in untrampled biocrusts. Replicate 16S rRNA T-RFLP profiles from trampled biocrusts at all three sites contained significantly more fragments (n17) than those of untrampled biocrusts (n6) and exhibited much higher variability among field replicates, indicating transition to an unstable disturbed state. Despite the dramatic negative impacts of trampling on biocrust physical structure and composition, M. vaginatus could still be detected in surface soils after 10 years of annual trampling, suggesting the potential for biocrust re-formation over time. Physical damage of biocrusts, in concert with changing temperature and precipitation patterns, has potential to alter performance of dryland ecosystems for decades. © 2012 International Society for Microbial Ecology All rights reserved.
URL: http://dx.doi.org/10.1038/ismej.2011.153
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Abstract: Lecanora pallidochlorina, formerly known only from the Sonoran region of Mexico, is reported new to the United States from several localities in or bordering the Cross Timbers of the Great Plains, where it occurs on sheltered siliceous rocks that are protected from direct wetting.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=289319
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Keywords: DEW DEPOSITION/ HEAT STORAGE/ MICROCLIMATE/ NONVASCULAR PLANTS/ PHYSIOLOGICAL ECOLOGY/ AMBIENT AIR/ DEW/ DIURNAL VARIATION/ ECOPHYSIOLOGY/ EPIPHYTE/ HEAT SOURCE/ LICHEN/ MICROCLIMATE/ NEOTROPIC ECOZONE/ PHOTOSYNTHESIS/ RADIATIVE TRANSFER/ RAINFOREST/ SURFACE TEMPERATURE/ TROPICAL FOREST/ UNDERSTORY/ WATER SUPPLY/ FRENCH GUIANA/ ANIMALIA
Abstract: • Additional water supplied by dew formation is an important resource for microbes, plants and animals in precipitation-limited habitats, but has received little attention in tropical forests until now. • We evaluated the micro-environmental conditions of tree stem surfaces and their epiphytic organisms in a neotropical forest, and present evidence for a novel mechanism of diurnal dew formation on these surfaces until midday that has physiological implications for corticolous epiphytes such as lichens. • In the understorey of a lowland forest in French Guiana, heat storage of stems during the day and delayed radiative loss during the night decreased stem surface temperatures by 6°C in comparison to the dew-point temperature of ambient air. This measured phenomenon induced modelled totals of diurnal dew formation between 0.29 and 0.69mmd on the surface of the bark and the lichens until early afternoon. • Crustose lichens substantially benefit from this dew formation, because it prolongs photosynthetic activity. This previously unrecognized mechanism of midday dew formation contributes to the water supply of most corticolous organisms, and may be a general feature in forest habitats world-wide. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.
URL: http://dx.doi.org/10.1111/j.1469-8137.2011.04034.x
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Keywords: BIOLOGICAL SOIL CRUSTS/ CEMENTING/ PHOTOTROPHIC ORGANISMS/ SUCCESSION/ VERTICAL STRATIFICATION
Abstract: In order to investigate succession of biological soil crusts (BSCs) and their microstructure variability, we conducted this work in Shapotou revegetation region at the southeast edge of Tengger Deser. The results showed that BSCs generally succeeded as a pathway of "Algae crusts, algae-lichen crusts, lichen crusts, lichen-moss crusts and moss crusts". Occasionally mosses directly occurred on algae crusts, and BSCs succeeded from algae crusts to moss crusts. Crust vertical stratification was a common phenomenon, from top to bottom an inorganic layer, algae-dense layer and algae-sparse layer were divided in algae crusts; a thallus layer, rhizoid layer and sub-rhizoid layer in lichen crusts; a "stem-leaf" layer, rhizoid layer and sub-rhizoid layer in moss crusts, respectively. The main crust binding organisms varied from filamental cyanobacteria (dominated by Microcoleus) in algae crusts to lichen rhizoids, free-living cyanobacterial filaments and fungal hyphaes in lichen crusts, and to moss rhizoids and fungal hyphaes in moss crusts. The dominant phototrophic organisms varied from Microcoleus (algae) in algae crusts to Collema (lichens) in lichen crusts, and to Bryum (or Didymodon and Tortula; mosses) in moss crusts. Total phototrophic biomass increased while the free-living algal biomass decreased with the succession of BSCs. In addition, exopolysaccharides and fine particles accumulated in the course of development and succession of BSCs, all of which lead to a gradual increase in crust thickness and porosity, while decrease in the bulk density. © 2011 Springer-Verlag.
URL: http://dx.doi.org/10.1007/s12665-011-1066-0
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Keywords: ALASKA/ BOREAL FOREST/ CARBON/ NITROGEN/ SPATIAL ANALYSIS/ WILDFIRE
Abstract: In this study we characterized spatial heterogeneity of soil carbon and nitrogen pools, soil moisture, and soil pH of the first 15 cm of the soil profile; depth of the organic horizon; forest floor covers; and understory vegetation abundances in three sites (1999, 1987 and 1920 wildfires) of a boreal forest chronosequence of interior Alaska. We also investigated the cross-dependence between understory vegetation distribution and soil characteristics. Our results showed higher microbial respiration rates and microbial biomass in the oldest site and greater net N mineralization rates in the mid-successional site. Although spatial heterogeneity was absent at the scale studied for the majority of soil variables (60%), understory vegetation abundances and forest floor cover, spatial heterogeneity decreased with time after fire for the depth of organic horizon, soil microbial biomass, N mineralization rates and feathermoss cover. Our results also showed that increasing time after fire decreased the number of correlations between understory vegetation and soil characteristics while it increased between forest floor covers and soil characteristics. Overall, our study suggest that fire initially creates a patchy mosaic of forest floor cover, from fire hot spots, where high intensity burning exposes mineral soil, to practically unburned areas with intact mosses and lichens. As time since fire passes, forest floor cover and soil characteristics tend to become more uniform as understory species fill in severely burned areas. © 2010 Springer Science+Business Media B.V.
URL: http://dx.doi.org/10.1007/s10533-010-9547-x
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Keywords: CRYPTIC SPECIES/ MORPHOLOGY/ SEMICRYPTIC SPECIES/ SPECIES CONCEPTS/ STERILE CRUSTOSE LICHENS
Abstract: Lepraria caesiella as currently circumscribed includes two sets of populations with different thallus morphologies. The populations are chemically identical but differ ecologically and are rarely sympatric. A phylogeny was inferred from ITS1, 5.8S, and ITS2 sequence data generated from a geographically broad sampling of the populations with each thallus type. Two strongly-supported clades were recovered that correlate to the two different morphotypes present within the species. Thus, L. caesiella is restricted to populations with aggregate thalli. Populations with placodioid thalli are formally described herein as a new species, L. harrisiana. A detailed taxonomic treatment of both taxa is presented. © 2012 Southern Appalachian Botanical Society.
Countries/Continents: North America/U.S.A./Canada
Notes: New species: L. harrisiana Lendemer
URL: http://www.bioone.org/doi/abs/10.2179/11-042
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Abstract: Notice is given regarding the formation of the International Committee for the Nomenclature of Lichens and Allied Fungi (or ICNLAF). The ICNLAF is an independent committee focused on the nomenclature of lichenized and allied fungi. The committee has no official authority to adjudicate matters of nomenclatural dispute and governance. It stands ready to consult with the other bodies on such matters however, and will accept such responsibility if mandated to do so by IAPT and the authorities that govern the ICN. In the event that the committee is charged by IAPT to govern lichen nomenclature, the ICNLAF will formally become active and the membership expanded to include appropriate equality in geographical and taxonomical representation.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=276109
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Keywords: DIMERIC LACCASE/ HUMIC ACIDS/ LICHENIZED ASCOMYCETES/ MONOMERIC LACCASE/ SOIL ORGANIC MATTER/ SYMBIOSIS/ TRANSFORMATION
Abstract: Lichens form the dominant plant cover in extreme environments and participate in mineral weathering, fine-earth stabilization and primary accumulation of soil organic matter. However, biochemical role of lichens in soil processes has never been investigated. Recently, laccases and tyrosinases have been discovered in representatives of the order Peltigerales (Laufer et al., 2006a, b; Zavarzina and Zavarzin, 2006). Laccases from most species had unusually large molecular weights (Laufer et al., 2009). Together with oligomeric laccases, we have found monomeric enzymes in Solorina crocea and Peltigera aphthosa (Lisov et al., 2007). In the present work we have purified homodimeric (large) and monomeric (small) laccases of the soil-stabilizing lichen S. crocea, determined their physico-chemical and catalytic properties and studied their reactions with soil humic acids. Our results suggest that oligomeric nature of lichen laccases can be artifactual, because homodimeric laccase was transformed into the monomeric form following hydrophobic interaction chromatography. We hypothesize that large laccase consists of two monomeric enzymes, each of which is bound with additional hydrophobic component(s). Small laccase is similar in its properties to the laccases of basidiomycetes. It is more resistant to elevated temperature and storage than the large form, showed a higher oxidation potential, had different pH-optima in oxidizing substrates and was less inhibited by humic acids. Despite these differences, both laccases depolymerized and decolorized humic acids from soils at comparable rates, with small laccase being slightly more effective. This finding suggests that lichens have a potential to participate in transformation of soil organic matter. © 2011 Elsevier Ltd.
URL: http://dx.doi.org/10.1016/j.soilbio.2011.11.004
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Keywords: BIODIVERSITY/ ENVIRONMENT QUALITY/ POLLUTION/ PORTUGAL
Abstract: Functional groups of epiphytic lichens are proposed as indicators of air quality in a Mediterranean urban area in the south of Portugal. Local land use: traffic (for areas near roads), green (for park areas) and house (residential areas); and bark pH are applied as proxies of air quality. Epiphytic lichen diversity was evaluated using lichen diversity values (LDV) methodology. Global LDV value decreases on traffic areas, as well as absolute values of LDV for the examined functional groups, which are lower in traffic areas than green and house areas. However, the composition of lichen communities shows a different pattern, based on the relative values of functional groups. Some functional groups, such as oligotrophic, hygrophytic and acidophilous lichens, are sensitive to pollution caused by traffic, and their richness declines markedly close to roads. These groups are well represented in areas without traffic, especially in park and residential areas. Otherwise, eutrophic, xerophytic and basophilous lichens are more represented in traffic areas. Sensitive functional groups seemed to be more reliable than total diversity for evaluating the impact of atmospheric pollution on small urban areas. © 2011 Elsevier Ltd.
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-80053231124&partnerID=40&md5=890d48c8de90fefa3b7196a44416789a
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Keywords: CHITOSAN/ ENDOLICHENIC FUNGI/ MANGROVE LICHENS/ ROCCELLA MONTAGNEI
Abstract: Objective: To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity. Methods: Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens. Results: Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli. Conclusions: In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.
URL: http://dx.doi.org/10.1016/S2221-1691(11)60208-6
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Keywords: ANTIOXIDANT ACTIVITY/ CHEMICAL COMPOSITION/ HPLC/ TONINIA CANDIDA
Abstract: In the present investigation, methanol, chloroform and petrol ether extracts from the lichen Toninia candida (Weber) Th. Fr, Catillariaceae, were assayed for their antioxidant activity. The phenolic composition of the extracts was determined by HPLC-UV analysis. The predominant phenolic compound in all the extracts was depsidone, norstictic acid. All the tested extracts of T. candida contain, besides norstictic acid, atranorin, stictic, protocetraric and usnic acid, but in different amounts and relations. The lichen extracts showed comparable and strong antioxidant activity, exhibited higher DPPH and hydroxyl radical scavengings, chelating activity and inhibitory activity towards lipid peroxidation. This is the first report of chemical composition and antioxidant antimicrobial activity of the lichen Toninia candida.
URL: http://dx.doi.org/10.1590/S0102-695X2011005000184
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Keywords: ATMOSPHERIC DEPOSITION/ LICHEN/ ORGANOCHLORINES/ PESTICIDES/ SIERRA NEVADA
Abstract: Deposition and accumulation of airborne organic contaminants in Yosemite National Park were examined by sampling atmospheric deposition, lichen, zooplankton, and lake sediment at different elevations. Passive samplers were deployed in high-elevation lakes to estimate surface-water concentrations. Detected compounds included current-use pesticides chlorpyrifos, dacthal, and endosulfans and legacy compounds chlordane, dichlorodiphenyltrichloroethane-related compounds, dieldrin, hexachlorobenzene, and polychlorinated biphenyls. Concentrations in snow were similar among sites and showed little variation with elevation. Endosulfan concentrations in summer rain appeared to coincide with application rates in the San Joaquin Valley. More than 70% of annual pesticide inputs from atmospheric deposition occurred during the winter, largely because most precipitation falls as snow. Endosulfan and chlordane concentrations in lichen increased with elevation, indicating that mountain cold-trapping might be an important control on accumulation of these compounds. By contrast, chlorpyrifos concentrations were inversely correlated with elevation, indicating that distance from source areas was the dominant control. Sediment concentrations were inversely correlated with elevation, possibly because of the organic carbon content of sediments but also perhaps the greater mobility of organic contaminants at lower elevations. Surface-water concentrations inferred from passive samplers were at sub-parts-per-trillion concentrations, indicating minimal exposure to aquatic organisms from the water column. Concentrations in sediment generally were low, except for dichlorodiphenyldichloroethane in Tenaya Lake, which exceeded sediment guidelines for protection of benthic organisms. © 2011 SETAC.
URL: http://dx.doi.org/10.1002/etc.1727
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Keywords: CASTANEA SATIVA/ COPPICE/ LICHEN DIVERSITY VALUE/ LOBARIA/ ORCHARD
Abstract: Chestnut forest ecosystems represent an important component of the European Mediterranean basin and the Southern Alps landscape. Despite the good knowledge acquired in the phytosanitary and cultural aspects of chestnut, there is still a lack of data on the relationships between chestnut and epiphytes. We have investigated the changes in frequency of occurrence and species composition of lichen assemblages against the main site characteristics and environmental variables in chestnut woods along a bioclimatic and geographical gradient in Central-North Italy. The study has highlighted a geographic gradient from the Western Alps to the Northern Apennines. We recorded a total of 152 taxa, only 49 of which occurring in all the bioclimatic zones. The distribution of lichen communities in chestnut stands is mainly associated with increasing precipitation and decreasing temperature, thus confirming the prevailing influence of macroclimatic factors on epiphytic lichens. The species composition statistically differs also in stands differently managed (orchards vs. coppices). Chestnut woods host interesting communities, with rare species related to Lobarion, and can represent a good habitat for threatened epiphytic species. © 2011 Versita Warsaw and Springer-Verlag Wien.
URL: http://dx.doi.org/10.2478/s11756-011-0145-8
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Keywords: CHINA, HENGDUAN MOUNTAINS, HIMALAYA MOUNTAINS, INDIA, LECANORALES, LICHENIZED ASCOMYCETES, LICHENIZED FUNGI, YUNNAN PROVINCE.
Abstract: The type of Hypogymnia delavayi, together with the two associated specimens collected by Delavay, fit perfectly the distinctive species currently known as H. yunnanensis. Accordingly, H. yunnanensis is placed in synonymy with the older name H. delavayi; this species is now known only from southwest China. Many specimens representing the common subalpine to alpine ground-dwelling species in northern India and Nepal, previously placed in H. delavayi, are referred to H. alpina Awasthi. Reports of H. delavayi from Far East Russia belong to other species.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=276111
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Keywords: BIOPITTING/ BIOTROUGHS/ KARST/ LICHEN/ LIMESTONE/ VERRUCARIA (BAGLIETTOA) BALDENSIS/ WEATHERING
Abstract: Data are reported demonstrating the potential role of microscale morphologies, induced by endolithic lichen communities, specifically Verrucaria baldensis, in the initiation and development of mesoscale solution basin formation on limestone in the Burren, County Clare. A biophysical model is proposed outlining the different microscale stages leading to solution basin initiation with a progression from initial lichen colonization and growth, associated perithecial biopitting followed by biopit coalescence to form biotroughs, their subsequent enlargement and eventual incipient solution basin formation. This model provides one explanation for solution basin development as this end state may also be achieved through simple solutional means without biological input. The complexity of interactions at the lichen-rock interface are identified with emphasis on the spatial and temporal variability of these underlining the point that, as with macrotopographies at the landscape scale, rock surface microtopographies also reflect historical weathering legacies. © 2011 John Wiley & Sons, Ltd.
URL: http://dx.doi.org/10.1002/esp.2244
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Abstract: A lichen monitoring program was implemented at Kejimkujik in 2006. At that time, lichens were collected in plots that were established for the monitoring program. These collections were added to all known lichen collections in the park and a provisional lichen list was developed. The monitoring program at Kejimkujik requires an assessment every five years; therefore, the second round of monitoring occurred in 2011. To increase the statistical power of the initial monitoring program six new plots were added to the original six, which led to the discovery of additional lichen species. New records for lichen species previously unreported in the park were also made outside of the study plots. Fifty-three new species were indentified in 2011, which brings the total number of known lichen species in Kejimkujik to 238 in 103 genera. Two of the new lichens discovered are listed by the Committee on the Status of Endangered Wildlife in Canada as species at risk, Erioderma mollissimum (endangered) and Degelia plumbea (special concern). One of the new species discovered is provincially red-ranked (at risk in Nova Scotia), which brings the total number of provincially red-ranked species known in the park to two: E. mollissimum and Xanthoparmelia mougeotii. Three of the new species discovered are provincially yellow-ranked (sensitive to disturbance), which increases the known yellow-ranked species in the park to nine: Anzia colpodes, Cladonia stygia, Leptogium corticola, L. milligranum, L. subtile, Physconia detersa, Sticta fuliginosa, Usnea cavernosa and U. mutabilis.
URL: http://sweetgum.nybg.org/philolichenum/biblio_detail.php?irn=289224
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Keywords: ATMOSPHERIC CONTAMINATION/ BIO-MONITOR/ METAL/ STABLE LEAD ISOTOPES
Abstract: More than 30 epiphytic lichens, collected in Agadir (Morroco) and along a 150-km transect from the Atlantic Ocean eastward, were analyzed for their metal content and lead isotopic composition. This dataset was used to evaluate atmospheric metal contamination and the impact of the city on the surrounding area. The concentrations of Cu, Pb, and Zn (average ± 1 SD) were 20.9 ± 15.2 µg g-1, 13.8 ± 9.0 µg g-1, and 56.6 ± 26.6 µg g-1, respectively, with the highest values observed in lichens collected within the urban area. The 206Pb/207Pb and 208Pb/207Pb ratios in the lichens varied from 1.146 to 1.186 and from 2.423 to 2.460, respectively. Alkyllead-gasoline sold in Morocco by the major petrol companies gave isotopic ratios of 206Pb/207Pb = 1.076-1.081 and 208Pb/207Pb = 2.348-2.360. These new, homogeneous values for gasoline-derived lead improve and update the scarce isotopic database of potential lead sources in Morocco, and may be of great value to future environmental surveys on the presence of lead in natural reservoirs, where it persists over time (e.g., soils and sediments). The interest of normalizing metal concentrations in lichens to concentrations of a lithogenic element is demonstrated by the consistency of the results thus obtained with lead isotopic ratios. Leaded gasoline contributed less than 50% of the total amount of lead accumulated in lichens, even in areas subject to high vehicular traffic. This strongly suggests that the recent banishment of leaded gasoline in Morocco will not trigger a drastic improvement in air quality, at least in Agadir. © 2011 Springer Science+Business Media B.V.
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-80052599585&partnerID=40&md5=fcd88fcb555cd274b740a0db5173a783
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Keywords: ATMOSPHERIC CONTAMINATION/ BIO-MONITOR/ METAL/ STABLE LEAD ISOTOPES
Abstract: More than 30 epiphytic lichens, collected in Agadir (Morroco) and along a 150-km transect from the Atlantic Ocean eastward, were analyzed for their metal content and lead isotopic composition. This dataset was used to evaluate atmospheric metal contamination and the impact of the city on the surrounding area. The concentrations of Cu, Pb, and Zn (average±1 SD) were 20.9±15.2 ?g g, 13.8±9.0 ?g g, and 56.6±26.6 ?g g, respectively, with the highest values observed in lichens collected within the urban area. The206Pb/207Pb and208Pb/207Pb ratios in the lichens varied from 1.146 to 1.186 and from 2.423 to 2.460, respectively. Alkyllead-gasoline sold in Morocco by the major petrol companies gave isotopic ratios of206Pb/207Pb=1.076-1.081 and208Pb/207Pb=2.348-2.360. These new, homogeneous values for gasoline-derived lead improve and update the scarce isotopic database of potential lead sources in Morocco, and may be of great value to future environmental surveys on the presence of lead in natural reservoirs, where it persists over time (e.g., soils and sediments). The interest of normalizing metal concentrations in lichens to concentrations of a lithogenic element is demonstrated by the consistency of the results thus obtained with lead isotopic ratios. Leaded gasoline contributed less than 50% of the total amount of lead accumulated in lichens, even in areas subject to high vehicular traffic. This strongly suggests that the recent banishment of leaded gasoline in Morocco will not trigger a drastic improvement in air quality, at least in Agadir. © Springer Science+Business Media B.V. 2011.
URL: http://dx.doi.org/10.1007/s11270-011-0942-2
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Keywords: BARK FEATURES/ EPIPHYTIC LICHENS/ FOREST MANAGEMENT/ HABITAT CHANGES/ SPECIES COMPOSITION/ SPECIES RICHNESS
Abstract: The responses of lichens to habitat changes caused by invasive trees are poorly understood. Invasive forest trees may impact epiphytic lichens by altering both substrate and stand conditions.Previous research has demonstrated that black locust invasion, associated with intensive exploitation of native oak forests, led to dramatic shifts in lichen composition. However, it is not clear if, along with stand aging, black locust formations regain forest species. The main aim of this study was to test whether the succession of black locust stands promotes a lichen succession leading to assemblages in mature black locust stands which are similar to those of native forests. To test the influence of macro-environmental conditions, we performed the study in two bioclimatically different areas of Italy. The epiphytic lichen biota of native oak and chestnut stands was compared with that of black locust stands of different successional stages. In both regions we did not find a lichen succession in black locust stands of different age, and mature black-locust stands did not recover the diversity of epiphytic species, which are lost by the replacement of the native forests by black locust. The absence of this pattern may be caused by factors related to the management of black locust stands, and to bark features. The different bioclimatic conditions between the two study areas may explain differences in the lichen biota of native forests, while that of black locust stands tend to be similar between regions, suggesting that forest habitat changes associated with the spread of black locust could decrease lichen diversity among bioclimatically different regions. © 2012 Elsevier B.V.
URL: http://dx.doi.org/10.1016/j.scitotenv.2012.01.051
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Keywords: ANTIOXIDANT/ APOPTOSIS/ CASPASE/ DIFFRACTAIC ACID/ OLIVE OIL/ TITANIUM ALLOY
Abstract: Usnea longissima Ach., a lichen species, is a traditional herbal medicine with anti-detrimental effects. We evaluated the in vivo effects of a major constituent of U. longissima, diffractaic acid, and the main fatty component of the Mediterranean diet, olive oil, against apoptosis, including various caspase activations and oxidative injury in surrounding tissues after titanium implantation in rabbit femurs. Furthermore, we evaluated the underlying molecular mechanisms. In this study, this lichen metabolite and olive oil activated caspase-dependent cell death with apoptotic morphology, which is distinctly different from necrosis. Both orally and locally administered olive oil and diffractaic acid exerted pro-apoptotic induction in tissues surrounding the implants in titanium-implanted rabbits through the activation of initiator caspases (Cas-2, -8 and -9) and executioner caspase (Cas-3). In addition, they displayed strong myeloperoxidase and inducible nitric oxide synthase activities, providing an alleviating effect. Furthermore, administrations of diffractaic acid and olive oil attenuated the Ti-alloy implantation, and decreased superoxide dismutase activity and total glutathione level in peri-implant tissues. These results demonstrate that diffractaic acid and olive oil are involved in the induction of apoptotic cell death both through caspase-dependent cell death and as an antioxidant. Thus, the data suggest that both diffractaic acid and olive oil could be developed as effective proapoptotic agents in various disorders treatments. © 2011 Elsevier B.V. All rights reserved.
URL: http://dx.doi.org/10.1016/j.ejphar.2011.11.019
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Keywords: BIOMONITORING/ DUST/ GASEOUS POLLUTANTS/ HEAVY METALS/ PASSIVE SAMPLERS/ RURAL AREA
Abstract: The immission and deposition levels of selected pollutants occurring in the area of a typical Polish village have been presented. In the course of a year-long research project (2009-2010), concentration levels of gaseous compounds in the air were determined (SO2, NO2, C6H6), as well as the level of solid particles deposition with the consideration of their chemical composition (Mn, Zn, Pb, Ni, Cd, Cu). Measurements were conducted in the area of rural settlements and at the site of plantation fields adjacent to the village. Classical analytical techniques (AAS, GC, IC) and biomonitoring with the use of mosses and lichens were used for the purposes of the study. Air quality in rural areas is determined mostly by the influence of the local sources (agricultural and uncontrolled emission) and that the quantity of toxicants enriching the environment depends on cyclical weather states periods characteristic for the temperate climate. Thespatial location of the village and meteorological conditions conducive to the spread and dilution of pollutants. Average monthly and the average annual concentrations of the classic gaseous atmosphere quality indicators do not entail the atmosphere's serious degradation. The presence of heavy metals and size of their deposition in the dust have shown that air quality is not at a satisfactory level. The deposition of solid particles is determined by the partition in the formation of emissions between uncontrolled and agricultural sources. The major source of the gas pollutants is associated with uncontrolled emission from residential and farm buildings. © 2011 Elsevier Ltd.
URL: http://dx.doi.org/10.1016/j.atmosenv.2011.12.049
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Keywords: BIODIVERSITY/ ECOLOGY/ EPIPHYTIC LICHENS/ QUERCUS/ TURKEY/ ANATOMY/ BIODIVERSITY/ EPIPHYTE/ LICHEN/ MORPHOLOGY/ MARMARA [TURKEY]/ TURKEY
Abstract: The epiphytic diversity of lichens associated with Quercus cerris L. and Quercus frainetto Ten. were investigated in 21 localities of the Marmara region. A total of 106 taxa belonging to 49 genera were reported on Q. cerris and Q. frainetto, and 16 of those taxa were recorded for the first time in the Marmara region. The number of lichen species found on Q. cerris was 83, while 85 taxa were found on Q. frainetto. Several differences regarding the lichen taxa were found in these 2 oaks species even though they were growing in the same habitat and in the same locality. Furthermore, some morphological, anatomical, and ecological peculiarities, as well as the phytogeographical patterns of the recorded lichen taxa, were evaluated. The majority of the lichen species were hygrophytic and mesophytic. In addition, nitrophytic species were more frequently observed than acidophytes. Temperate and suboceanic species were the most common. © Tübi?tak.
URL: http://dx.doi.org/10.3906/bot-1003-18
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Keywords: CALIBRATION/ CENTROID/ CLUSTER ANALYSIS/ EUCLIDEAN DISTANCE/ FUEL CHARACTERISTIC CLASSIFICATION SYSTEM/ SURFACE FUELS
Abstract: Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or thousands of measured surface fuelbeds representing the fine scale variation in fire behavior on the landscape is constrained in terms of creating compatible custom fire behavior fuel models. In this study, we demonstrate an objective method for taking ecologically complex fuelbeds from inventory observations and converting those into a set of custom fuel models that can be mapped to the original landscape. We use an original set of 629 fuel inventory plots measured on an 80,000ha contiguous landscape in the upper Atlantic Coastal Plain of the southeastern United States. From models linking stand conditions to component fuel loads, we impute fuelbeds for over 6000 stands. These imputed fuelbeds were then converted to fire behavior parameters under extreme fuel moisture and wind conditions (97th percentile) using the fuel characteristic classification system (FCCS) to estimate surface fire rate of spread, surface fire flame length, shrub layer reaction intensity (heat load), non-woody layer reaction intensity, woody layer reaction intensity, and litter-lichen-moss layer reaction intensity. We performed hierarchical cluster analysis of the stands based on the values of the fire behavior parameters. The resulting 7 clusters were the basis for the development of 7 custom fire behavior fuel models from the cluster centroids that were calibrated against the FCCS point data for wind and fuel moisture. The latter process resulted in calibration against flame length as it was difficult to obtain a simultaneous calibration against both rate of spread and flame length. The clusters based on FCCS fire behavior parameters represent reasonably identifiable stand conditions, being: (1) pine dominated stands with more litter and down woody debris components than other stands, (2) hardwood and pine stands with no shrubs, (3) hardwood dominated stands with low shrub and high non-woody biomass and high down woody debris, (4) stands with high grass and forb (i.e., non-woody) biomass as well as substantial shrub biomass, (5) stands with both high shrub and litter biomass, (6) pine-mixed hardwood stands with moderate litter biomass and low shrub biomass, and (7) baldcypress-tupelo stands. Models representing these stand clusters generated flame lengths from 0.6 to 2.3m using a 30kmh wind speed and fireline intensities of 100-1500kWm that are typical within the range of experience on this landscape. The fuel models ranked 1<2<7<5<4<3<6 in terms of both flame length and fireline intensity. The method allows for ecologically complex data to be utilized in order to create a landscape representative of measured fuel conditions and to create models that interface with geospatial fire models. © 2012 Elsevier B.V.
URL: http://dx.doi.org/10.1016/j.foreco.2012.01.024
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Keywords: CONSERVATION/ DISTRIBUTION RANGES/ HABITAT COMPONENTS/ LEPIDOPTERA/ LIFE HISTORY TRAITS/ PALAEARCTIC REGION
Abstract: To be used as a predictive conservation tool, classification of animal habitats should rely on actual resource requirements of individual species. Shreeve et al. (J Insect Conserv 5:145-161, 2001) produced a resource-based habitat classification for British butterflies, obtaining habitat association groups, whose constituent species differed in their distribution extent, distribution change and vulnerability in Britain. To test the utility of this approach for a group with a less-known biology, we produced a resource-based classification of habitats of Central European macromoths. We worked with macrolepidopteran moth families, except for the megadiverse Geometridae and Noctuidae. We produced a matrix of 178 life history attributes describing resource use by 164 species, subjected the matrix to ordination analysis, and compared the resulting moths groupings with external ecological information. Five habitat association groups were distinguished: I-close canopy moths, II-open canopy moths, III-grasslands moths, IV-herb-feeding hawk moths, and V-lichen feeders. The classification sustained deleting attributes related to host plants taxonomy. Groups I-III sustained control for taxonomic positions of the moths, whereas IV and V did not. Members of the groups differed in the representation of externally obtained habitat associations, biogeography elements, threat status, and range size. Endangered species were over-represented in groups II and III and underrepresented in group I, in agreement with recent land cover changes across the continent. Species resources can be used to reconstruct their habitat needs, and it is possible to scale up from life histories through habitat use to range structures. © 2011 Springer Science+Business Media B.V.
URL: http://dx.doi.org/10.1007/s10841-011-9405-8
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Keywords: BIODIVERSITY, LA PALMA, LICHEN, MACARONESIA, TAXONOMY
Abstract: Diploschistes albopruinosus is described as new to science. This species is found on siliceous rocks in La Caldera de Taburiente National Park (La Palma, Canary Islands). A description of the species is given together with notes on its chemistry, distribution, ecology and taxonomy. Related lichen taxa are discussed.
Notes: New species: Diploschistes albopruinosus Pérez-Vargas, C. Hdez.-Padr. & Elix
URL: http://dx.doi.org/10.1017/S0024282911000612
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Keywords: BIODIVERSITY/ CHECKLIST/ LICHENS/ SOUTH CAROLINA/ FOREST
Abstract: The Tuckerman Lichen Workshop is an annual event where professional and amateur lichenologists convene to practice their skills in lichen identification while exploring the lichen diversity of an area in eastern North America. The 19th workshop in this series was
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Keywords: BIODIVERSITY/ BOG/ DUNE/ ECOSYSTEM SERVICES/ GRASSLAND/ HEATHLAND/ POLLUTION/ SOIL
Abstract: Atmospheric nitrogen (N) deposition is a global and increasing threat to biodiversity and ecosystem function. Much of our current understanding of N deposition impacts comes from field manipulation studies, although interpretation may need caution where simulations of N deposition (in terms of dose, application rate and N form) have limited realism. Here, we review responses to simulated N deposition from the UKREATE network, a group of nine experimental sites across the UK in a diversity of heathland, grassland, bog and dune ecosystems which include studies with a high level of realism and where many are also the longest running globally on their ecosystem type. Clear responses were seen across the sites with the greatest sensitivity shown in cover and species richness of bryophytes and lichens. Productivity was also increased at sites where N was the limiting nutrient, while flowering also showed high sensitivity, with increases and declines seen in dominant shrub and forb species, respectively. Critically, these parameters were responsive to some of the lowest additional loadings of N (7.7-10 kg ha yr) showing potential for impacts by deposition rates seen in even remote and 'unpolluted' regions of Europe. Other parameters were less sensitive, but nevertheless showed response to higher doses. These included increases in soil %N and 'plant available' KCl extractable N, N cycling rates and acid-base status. Furthermore, an analysis of accumulated dose that quantified response against the total N input over time suggested that N impacts can 'build up' within an ecosystem such that even relatively low N deposition rates can result in ecological responses if continued for long enough. Given the responses have important implications for ecosystem structure, function, and recovery from N loading, the clear evidence for impacts at relatively low N deposition rates across a wide range of habitats is of considerable concern. © 2011 Blackwell Publishing Ltd.
URL: http://dx.doi.org/10.1111/j.1365-2486.2011.02590.x
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Abstract: Nitrogen (N) has emerged in recent years as a key factor associated with global changes, with impacts on biodiversity, ecosystems functioning and human health. In order to ameliorate the effects of excessive N, safety thresholds such as critical loads (deposition fluxes) and levels (concentrations) can be established. Few studies have assessed these thresholds for semi-natural Mediterranean ecosystems. Our objective was therefore to determine the critical loads of N deposition and long-term critical levels of atmospheric ammonia for semi-natural Mediterranean evergreen woodlands. We have considered changes in epiphytic lichen communities, one of the most sensitive comunity indicators of excessive N in the atmosphere. Based on a classification of lichen species according to their tolerance to N we grouped species into response functional groups, which we used as a tool to determine the critical loads and levels. This was done for a Mediterranean climate in evergreen cork-oak woodlands, based on the relation between lichen functional diversity and modelled N deposition for critical loads and measured annual atmospheric ammonia concentrations for critical levels, evaluated downwind from a reduced N source (a cattle barn). Modelling the highly significant relationship between lichen functional groups and annual atmospheric ammonia concentration showed the critical level to be below 1.9 ?gm-3, in agreement with recent studies for other ecosystems. Modelling the highly significant relationship between lichen functional groups and N deposition showed that the critical load was lower than 26 kg (N) ha yr, which is within the upper range established for other semi-natural ecosystems. Taking into account the high sensitivity of lichen communities to excessive N, these values should aid development of policies to protect Mediterranean woodlands from the initial effects of excessive N. © Author(s) 2012.
URL: http://dx.doi.org/10.5194/bg-9-1205-2012
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Abstract: Abstract: Phenotypic characters, either morphological or chemical, have shown to be insufficient to delimit species boundaries in the genus Cladonia. The present study addresses the circumscription of species within the Cladonia cariosa group, examining a number of specimens of the currently accepted taxa Cladonia cariosa, C. symphycarpa, C. acuminata, C. subcariosa and C. latiloba. We employed maximum likelihood and Bayesian methods of phylogenetic reconstructions based on DNA sequences of ITS, rpb2 and ef1 regions. Our results show that the C. cariosa group consists of at least four phylogenetic lineages. It is also shown that each of these lineages is chemically variable, which restricts the taxonomic value of the chemical differences within the group. However, anatomical differences, such as squamule surface and cortex structure, were found to correlate with the distinct lineages found in the phylogenetic analysis. This result confirms the taxonomic value of the cortical surface under SEM, as was found in other lichen groups.
Genera/Families: Cladoniaceae
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New taxa: Cladonia corsicana
Genera/Families: Cladonia
Notes: New combination: Cladonia corsicana (Rondon & Vězda) Pino-Bodas, Burgaz & M. P. Martín
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Keywords: AGE AND SIZE AT MATURITY/ ARCTIIDAE/ DEVELOPMENTAL PLASTICITY/ GROWTH RATE/ INSTAR NUMBER VARIABILITY/ LEPIDOPTERA/ LITHOSIINAE/ MELANOHALEA EXASPERATA/ PARMELIA SULCATA/ REACTION NORM
Abstract: According to life-history theory, longer development time may result in bigger adults. However, reaction norms describing age and size at maturity often follow an L-shaped form. This relationship is attributable to the simple notion that slowly growing individuals may not lengthen their development excessively after the maturation decision has been made, for example, when development is time limited in seasonal environments. In arthropods, growth occurs within instars, and thus the optimal growth strategy might be mediated by the phenotypic adjustment of instar numbers. We studied the relationship between age and size at maturity of a lichen-feeding moth, Eilema depressum (Esper) (Lepidoptera: Arctiidae: Lithosiinae), and the variability of instar numbers in relation to achieved adult body mass and time used for maturation. A positive relationship between age and size at maturity was found across developmental pathways and a negative one within the developmental pathways. Directly developing larvae had higher growth rates, attained smaller pupal mass, and passed fewer instars than larvae maturing after overwintering. Host quality did not affect whether larvae matured during the remaining or the next season. High variation in the number of instars together with variable growth rates indicates high plasticity in adaptation to varying environmental conditions. Our results also confirm previous results that instar number variability may be a key characteristic mediating age and size at maturity in insects. © 2012 The Authors. Entomologia Experimentalis et Applicata © 2012 The Netherlands Entomological Society.
Notes: The subject of the study feeds on lichens.
URL: http://dx.doi.org/10.1111/j.1570-7458.2011.01208.x
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Keywords: ANTHRACOCARPON/ CATAPYRENIUM S.L./ CHARACTER EVOLUTION/ CLAVASCIDIUM/ INVOLUCROPYRENIUM/ MEDULLA/ NEW COMBINATIONS/ PYCNIDIA POSITION/ RHIZINES
Abstract: Premise of the study: Verrucariaceae is a fascinating lineage of lichenized fungi for which generic and species delimitation is problematic due to the scarcity of discriminating morphological characters. Members of this family inhabit rocks, but they further colonize soils, barks, mosses, and other lichens. Our aim is to contribute to the DNA-based inference of the Verrucariaceae tree of life and to investigate characters that could be useful for proposing a more natural classification. We focused on catapyrenioid genera, which are often part of biological soil crusts, a cryptogam-dominated ecosystem contributing to soil formation and stabilization in arid environments. Understanding their evolution and taxonomy is essential to assess their roles in these fragile and important ecosystems. Methods: A multigene phylogeny of Verrucariaceae including catapyrenioid genera is presented. We further examined the phylogenetic relationships among members of Heteroplacidium and Placidium. The evolution of selected characters was inferred using the latter phylogeny. Key results: Anthracocarpon and Involucropyrenium were closely related to Endocarpon. Placidium comprised two monophyletic clades sister to Heteroplacidium. Inferred ancestral states of diagnostic characters revealed that the type of medulla and the pycnidia location were homoplasious within the Placidium clade. In contrast, the presence of rhizines was a synapomorphy for Clavascidium. Conclusions: Our results provide new information on the usefulness of characters for delineating groups in Verrucariaceae. Taxonomic changes are proposed to reflect more natural groupings: Heteroplacidium podolepis is transferred to Placidium, and Clavascidium is recognized as a different genus. Eight new combinations are proposed for Clavascidium. © 2012 Botanical Society of America.
Notes: New combinations: Clavascidium lacinulatum (Ach.) M. Prieto, C. lacinulatum var. atrans (Breuss) M. Prieto, C. lacinulatum var. erythrostratum (Breuss) M. Prieto, C. lacinulatum var. latisporum (Breuss) M. Prieto, C. semaforonense (Breuss) M. Prieto, C. pseudorufescens (Breuss) M. Prieto, C. imitans (Breuss) M. Prieto, C. krylovianum (Tomin) M. Prieto & Placidium podolepis (Breuss) M. Prieto.
URL: http://dx.doi.org/10.3732/ajb.1100239
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Keywords: AIR TEMPERATURE/ CARBON BALANCE/ DEW/ LICHENS/ POIKILOHYDRIC PLANTS/ RADIATION
URL: http://dx.doi.org/10.1111/j.1469-8137.2012.04082.x
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Abstract: Lichen species belonging to the genus Placopsis are early colonisers on snow free moraines of exposed land surfaces in the subantarctic region of Tierra de Fuego, South Chile. The physiological performance of three co-occurring species, P. pycnotheca, (terricolous), and P. perrugosa, and P. stenophylla (both saxicolous) was studied. All, possess green algal photobionts but have cyanobacteria in cephalodia. It was found that there was (i) a strong positive correlation between the acetylene reduction rate (AR) and the maximum photosynthetic rate (Amax), between the N content and the AR rate, and between the N and P contents, and (ii) the relationship between the CO2-exchange rates and the responses obtained in the laboratory reflected the ecology of these three lichens in the field. The results provide new information about the dynamics of some of the fastest growing crustose lichens. We hypothesize that the performance of these three species may have developed as a response to growing in an unstable environment that resulted from frequent glacial fluctuations.
URL: http://dx.doi.org/10.1007/s13199-012-0159-1
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Keywords: BIOINDICATORS/ DISTURBANCES/ GARHWAL HIMALAYA/ GRAZING/ TRAMPLING
Abstract: Lichens are among the most sensitive biomonitors of ecosystem health and human induced disturbances. Terricolous lichens of Chopta-Tungnath (Garhwal, western Himalaya, India) were analysed for their ability to indicate habitat variability and disturbances induced by livestock grazing. Terricolous lichens were sampled from 12 sites, distributed across the three macrohabitats between 2,700 and 4,001 m, using 50 × 10 cm narrow frequency grids having five 10 × 10 cm sampling units. The terricolous lichen community of the area constituted, 20 species belonging to 10 genera, five families and four growth forms. Altitude and relative humidity were the major habitat factors found influencing the terricolous lichen community of the landscape. Fruticose and compound soil lichen growth forms were found indicative of habitat disturbance largely caused by grazing induced trampling. Terricolous lichen diversity of the area was delimited by grazing pressure at mid-altitudes (3,000-3,400 m) and by decreasing soil cover at higher altitudes (>3,400 m). © 2011 Springer Science+Business Media B.V.
URL: http://dx.doi.org/10.1007/s10531-011-0168-z
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Keywords: ARTEMIA NAUPLII/ BRINE SHRIMP LETHALITY/ CYTOTOXICITY/ EVERNIASTRUM CIRRHATUM (FR.) HALE/ LC50 / WELL-IN-AGAR METHOD
Abstract: Everniastrum cirrhatum (Fr.) Hale (Parmeliaceae) is a foliose macrolichen which usually grows on the barks of trees in temperate regions. In the present study, we report for the first time antifungal and cytotoxic activity of E. cirrhatum. The dried lichen material was powdered and extracted with methanol using by soxhlet apparatus. Antifungal activity of extract (10-100 mg/ml) was tested against two clinical fungal isolates namely Candida albicans and Cryptococcus neoformans by well-in-agar method. Cytotoxic activity of extract (0
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-84856563264&partnerID=40&md5=d3278da69c1be2fe878d6b1269033cef
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URL: http://www.pakbs.org/pjbot/PDFs/44%281%29/65.pdf
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Keywords: ANTARCTICA/ DEBARYOMYCES/ HELICODENDRON/ SOIL FUNGI/ ZALERION
Abstract: The McMurdo Dry Valleys of Antarctica present extreme environmental challenges. Life is restricted to patchy occurrence of lichens, mosses and invertebrates, plus soil microbial communities. Fungi have been described in lichen symbioses but relatively little is known about the occurrence of free-living soil fungi in the Dry Valleys. A challenge in estimating fungal species richness has been the extent to which estimates based on either cultivation or environmental DNA reflect the active assemblage in cold-arid soils. Here, we describe analysis for inland Dry Valleys soil of environmental DNA and RNA (cDNA) to infer total and putative metabolically active assemblages, respectively, plus cultivation approaches using a variety of laboratory growth conditions. Environmental sequences indicated a highly restricted assemblage of just seven phylotypes that affiliated phylogenetically within two known genera, Helicodendron and Zalerion, plus previously unidentified fungal phylotypes. None of the commonly encountered molds and mitosporic genera recorded from maritime Antarctic locations were encountered. A striking difference was observed in the frequency of recovery for phylotypes between libraries. This suggests that both species richness and beta diversity estimates based on DNA libraries have the potential to misinform putatively active assemblages. Cultivation yielded a cold-tolerant Zalerion strain that affiliated with DNA and RNA library clones, and a psychrotrophic yeast (Debaryomyces hansenii), which was not detected using either culture-independent approach. © 2011 The Author(s).
URL: http://dx.doi.org/10.1007/s00300-011-1102-2
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Keywords: ANATOMY/ CHEMISTRY/ LOBARIACEAE/ MORPHOLOGY
Abstract: Lobaria (Schreb.) Hoffm is a common foliose lichen genus found on the Korean Peninsula, yet until now, no revision study has been done on this genus. After careful examination of specimens deposited in the Korean Lichen Research Institute (KoLRI), nine distinct species of Lobaria were confirmed. Morphological characteristics such as the presence or absence of isidia, or whether or not the surface was ridged or smooth, and chemical characteristics such as the result of the medulla reaction were of significant importance in the differentiation of species. Here, we provided detailed descriptions together with a key to all the known Korean species.
Genera/Families: Lobaria
URL: http://dx.doi.org/10.5941/MYCO.2012.40.1.001
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Abstract: A revised classification for the emended family Graphidaceae is proposed, based on recent phylogenetic studies, including the finding that three previously separated families (Asterothyriaceae, Gomphillaceae, Thelotremataceae) are nested within Graphidaceae and in part polyphyletic. The family comprises three major clades which are here delimited as subfamilies Fissurinoideae, Gomphilloideae, and Graphidoideae. The latter is composed of three major clades which are formally delimited as tribes Graphideae, Ocellularieae, and Thelotremateae. In addition, three new genera are described to accommodate the Ocellularia clandestina (Clandestinotrema)group, the Ocellularia cruentata group (Cruentotrema)and Myriotrema pycnoporellum (Pycnotrema). Keys are provided for the species placed in the new genera.
Genera/Families: Graphidaceae
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Keywords: COASTAL HABITATS/ LATITUDINAL GEOGRAPHIC GROUPS/ LICHENS/ LIFE FORMS/ SUBSTRATE GROUPS
Abstract: The distribution of morphological, substrate, and latitudinal geographic groups of lichen species has been analyzed in various habitat types on the northwestern coast of the Sea of Japan. The results show that the influence of the sea manifests itself in the presence of halophytes, xerophytic life forms, and species of the suboceanic latitudinal geographic group; soil-plant conditions account for the development of the substrate group of epiphytic lichens, mesophytic life forms, and species of the nemoral latitudinal geographic group. © 2012 Pleiades Publishing, Ltd.
URL: http://dx.doi.org/10.1134/S1067413612020117
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Keywords: CLIMATE/ LICHEN/ MICROBIOTIC SOIL CRUST/ SAGEBRUSH/ SOIL PH/ SOIL TEXTURE
Abstract: Biological soil crusts are ecosystem engineers in arid and semi-arid habitats; they affect soil chemistry, stability, and vegetation. Little is known about regional variation in biotic crust communities of North America. We explored how biotic crust lichen community composition and richness are related to vascular plant, soil and climate characteristics in Oregon. In 59 0.4-ha plots, we found 99 biotic crust lichen species, one-third of which were observed only once. Biotic crust lichen communities rich in cyanolichens characterized Juniperus stands whereas warm grasslands were home to regionally uncommon species including Texosporium sancti-jacobi and Rhizocarpon diploschistidina. We discerned biotic crust communities in sandy Artemisia tridentata ssp. wyomingensis sites from those loamy A.arbuscula sites. Hotspots of biotic crust lichen species richness were geographically scattered, weakly negatively associated with abundance of shrubs of disturbed sites. Gutierrezia and Chrysothamnus. The sites with lowest biotic crust lichen richness were heavily grazed, burned plots with Gutierrezia in the grassy north; unstable steep talus slopes at the center of the study area; and sandy, grazed sites with Chrysothamnus in the southern portion of our region. Overall, regional patterns in biotic crust lichen communities were strongly associated with vegetation, soils, and climate. © 2011.
URL: http://dx.doi.org/10.1016/j.jaridenv.2011.11.017
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Abstract: La liste des lichens et champignons lichénicoles de France métropolitaine (Corse incluse, départements et territoires d'outremer exclus) comprend 3435 taxons signalés correctement en France (2917 lichens, 461 champignons lichénicoles non lichénisés et 57 champignons non lichénicoles non lichénisés habituellement considérés par les lichénologues), 319 à rechercher en France, 31 non connus avec certitude en France et 65 signalés à tort en France. Un appendice systématique comprend la description d'une espèce nouvelle (Diplotomma renobalesii Cl. Roux sp. nova), la proposition de 5 combinaisons nouvelles [Alyxoria subrimalis (Nyl.) Cl. Roux et Poumarat comb. nova, Halospora deminuta subsp. longispora (Cl. Roux et Nav.-Ros.) Cl. Roux et Nav.-Ros. comb. nova, Lobothallia cernohorskyana (Clauzade et Vězda) A. Nordin, Cl. Roux et Sohrabi, Lobothallia chadefaudiana (Cl. Roux) A. Nordin, Cl. Roux et Sohrabi comb. nova, Lobothallia cheresina (Müll. Arg.) A. Nordin, Cl. Roux et Sohrabi comb. nova] et des remarques sur des espèces mal connues, Aspicilia viridescens (A. Massal.) Hue, Caloplaca necator Poelt et Clauzade (syn. Caloplaca inconnexa var. nesodes Poelt et Nimis), Parmelia duboscqii Abbayes [synonyme de Parmelina carporrhizans (Taylor) Poelt et Vězda] et sur le genre Myriospora.
Notes: New species: Diplotomma renobalesii Cl. Roux; new combinations: Alyxoria subrimalis (Nyl.) Cl. Roux et Poumarat, Halospora deminuta subsp. longispora (Cl. Roux et Nav.-Ros.) Cl. Roux et Nav.-Ros., Lobothallia cernohorskyana (Clauzade et Vězda) A. Nordin, Cl. Roux et Sohrabi, Lobothallia chadefaudiana (Cl. Roux) A. Nordin, Cl. Roux et Sohrabi, Lobothallia cheresina (Müll. Arg.) A. Nordin, Cl. Roux et Sohrabi; in French and Esperanto
URL: http://slprovence.olympe-network.com/telechargements/Roux-2012_Liste-Lichens-France_Bulletin-Societe-Linneenne-Provence_numero-special-16.pdf
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Keywords: BIOACCUMULATION/ INDIA/ KANPUR CITY/ PAHS/ RINODINA SOPHODES/ TRAFFIC LEVEL/ INDIA/ KANPUR CITY/ PAHS/ RINODINA SOPHODES/ TRAFFIC LEVEL/ AROMATIC COMPOUNDS/ BIOACCUMULATION/ BIOCHEMISTRY/ HYDROCARBONS/ POLLUTION/ POLYCYCLIC AROMATIC HYDROCARBONS/ ACENAPHTHYLENE/ PHENANTHRENE/ POLYCYCLIC AROMATIC HYDROCARBON/ ATMOSPHERIC POLLUTION/ BIOACCUMULATION/ BIOMONITORING/ COMBUSTION/ CONCENTRATION (COMPOSITION)/ DETECTION METHOD/ FUNGUS/ LICHEN/ PAH/ POLLUTANT SOURCE/ TRAFFIC EMISSION/ AIR POLLUTION INDICATOR/ ARTICLE/ ATMOSPHERIC DEPOSITION/ BIOACCUMULATION/ BIOLOGICAL MONITORING/ CONCENTRATION (PARAMETERS)/ CONTROLLED STUDY/ ENVIRONMENTAL IMPACT ASSESSMENT/ EXHAUST GAS/ HEALTH HAZARD/ INDIA/ INDICATOR ORGANISM/ LICHENS/ LIMIT OF DETECTION/ NONHUMAN/ ORGANIC POLLUTION/ PLANT GROWTH/ POLLUTION MONITORING/ QUANTITATIVE ANALYSIS/ RINODINA SOPHODES/ RISK ASSESSMENT/ TROPICS/ INDIA/ KANPUR/ UTTAR PRADESH/ RINODINA SOPHODES
Abstract: The aim of this study is to determine the possibility of using Rinodina sophodes (Ach.) Massal., a crustose lichen as polycyclic aromatic hydrocarbons (PAHs) bioaccumulator for evaluation of atmospheric pollution in tropical areas of India, where few species of lichens are able to grow. PAHs were identified, quantified and compared to evaluate the potential utility of R. sophodes. The limit of detection for different PAHs was found to be 0.008-0.050 ?g g- 1. The total PAHs in different sites were ranged between 0.189 ± 0.029 and 0.494 ± 0.105 ?g g-1. The major sources of PAHs were combustion of organic materials, traffic and vehicular exhaust (diesel and gasoline engine). Significantly higher concentration of acenaphthylene and phenanthrene indicates road traffic as major source of PAH pollution in the city. Two-way ANOVA also confirms that all PAHs content showed significant differences between all sampling sites (P 1%). This study establishes the utility of R. sophodes in monitoring the PAHs accumulation potentiality for development of effective tool and explores the most potential traits resistant to the hazardous environmental conditions in the tropical regions of north India, where no such other effective way of biomonitoring is known so far. © 2011 Springer Science+Business Media B.V.
URL: http://dx.doi.org/10.1007/s10661-011-1962-5
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Abstract: The endosymbiotic bacterium Sphingomonas sp. strain PAMC 26605 was isolated from Arctic lichens (Ochrolechia sp.) on the Svalbard Islands. Here we report the draft genome sequence of this strain, which could provide further insights into the symbiotic mechanism of lichens in extreme environments. © 2012, American Society for Microbiology.
URL: http://dx.doi.org/10.1128/JB.00004-12
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Keywords: AL:CA RATIO/ BASE CATIONS/ INLAND DUNES/ LICHENS/ SOIL ACIDIFICATION
Abstract: Background and aims: Primary succession was studied in acid inland drift sands. Main research questions were: 1) How do vegetation and soil change during succession? 2) How are soil parameters and species abundance affected by atmospheric nitrogen deposition?Methods: One hundred sixty-five plots were selected in 21 drift sands throughout The Netherlands, divided over eight succession stages from bare sand to dry heath and within a gradient in nitrogen deposition. Vegetation development and soil parameters were described and water-extractable elements measured and differences between high (>30 kg N ha year) and lower nitrogen deposition sites calculated. Results: Vegetation cover and height increased during succession. Lichens contributed most to plant species diversity. Thickness of Ah horizon increased and pH decreased and concentrations of Fe, Al, S increased. Base cations increased as well, despite the drop in pH. Also, water-extractable ammonium, nitrate and phosphate increased, along with the NH4:NO3 ratio. Sites with high nitrogen deposition had higher NH4:NO3 and Al:Ca ratios, lower pH, higher cover of algae, lower lichen and total species diversity, more Pinus sylvestris seedlings and more species of late succession stages. Conclusions: Drift sand succession seems to be mainly driven by an increase in organic matter, but is accelerated by nitrogen deposition. © 2011 The Author(s).
URL: http://dx.doi.org/10.1007/s11104-011-1029-y
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Keywords: ARCTIC/ HERBIVORY/ LICHENS/ MANAGEMENT/ RECOVERY/ REINDEER/ SUSTAINABILITY/ WINTER GRAZING
Abstract: During the last 25. yr, Sami reindeer husbandry in parts of Finnmarksvidda in the Norwegian Arctic has been in a critical state because of overexploitation of lichen-dominated tundra, which serves as winter forage. To better understand the ecosystem's capabilities for recovery we investigated vegetation cover changes over a 7-yr period, starting in 1998, at 52 sites dispersed over a large area at Finnmarksvidda. Two types of plots were established: one fenced from reindeer grazing and trampling and one open for reindeer. The investigations in 2005 showed that lichen cover had had a significant and rapid increase (up to 8.6-fold per year). The cover of vascular plants, mainly dwarf shrubs, also increased significantly, while barren areas and the cover of litter decreased significantly during the period. Mean relative growth rate of lichen biomass was 0.083 ± 0.011 per year in open plots, which is considered very rapid recovery compared to previous studies. Lichen recovery was significantly faster on leeward ridges than on exposed ridges, and fencing alone did not have any significant effects on lichen recovery, but in interaction with time, fencing contributed to increasing recovery rates. The lichen heath recovery was reciprocally correlated with reindeer density. In addition, lichen recovery was probably facilitated by recent climate changes, viz. shallower snow depths which made leeward tundra and forest floor vegetation accessible for reindeer, and increased summer precipitation rates which improved growth rates. The results from this study show that in a very short time there was a transition from an overexploited depauperate vegetation and barren ground state to a flourishing lichen-dominated vegetation state, suggesting that the injuries were repairable. The vegetation transitions which have taken place in the study area are considered to be reversible with fewer persistent effects. © 2011 Elsevier Ltd and The British Mycological Society.
URL: http://dx.doi.org/10.1016/j.funeco.2011.08.002
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Keywords: DROUGHT HYPOTHESIS/ HYDRATION/ NOX/ O3/ POLLUTION/ TRANSPLANT
Abstract: The hypothesis that a daily water supply allows a lichen to endure the negative effects of environmental concentrations of NOx and O3 was tested with a transplant experiment. Five groups (0, A-D) of Flavoparmelia caperata samples derived from the same thalli were used for destructive, pre-exposure measurements (0), or exposed for 5 weeks in the rural collection site (A), and in a urban site with high levels of NOx and O3 (B-D). Two groups (C, D) were daily watered half an hour before the daily peak of NOx (C), and O3 (D). The comparison between pre- and post-exposure measurements of stress biomarkers revealed that the different thallus hydration regime modified the pollution tolerance as well as the physiology of the exposed samples. The non-watered group B suffered an evident decrease in Fv/Fm and reduced glutathione, but increased ion leakage, whereas the watered groups C and D showed only decreased non-photosynthetic-quenching, possibly derived from NOx exposure. Ozone, which was higher in the rural than in the urban site, did not significantly affect the lichen metabolism. Our results re-open the discussion on the so-called "drought hypothesis", which suggests that the lichen desert observed in urban areas of central and eastern Europe is more a matter of dry microclimate than of air pollution. © 2011 Springer-Verlag.
URL: http://dx.doi.org/10.1007/s00442-011-2104-z
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Keywords: DERMATOCARPON INTESTINIFORME/ GENOTOXICITY/ HUMAN LYMPHOCYTES/ MERCURIC CHLORIDE/ MICRONUCLEUS/ SISTER CHROMATID EXCHANGE
Abstract: Mercury has been used in many domains of human activities for many years, although in any form mercury is reported to be toxic. On the other hand, lichens have been used in the treatment of several diseases such as tuberculosis, hemorrhoids, ulcer, dysentery and cancer. Animal investigations on some common lichen species have demonstrated their antioxidant and antimutagenic activity. However, there is very scarce data on the medical or biologic effects of specific lichen species. Therefore, in the present study, we assessed the cyotogenetic effects of mercuric chloride (HgCl2) and the role of aqueous Dermatocarpon intestiniforme lichen extracts in mercury-treated human blood cultures (n = 3). The sister chromatid exchange (SCE) and micronucleus (MN) assays were performed to assess DNA damages in lymphocytes. Our results clearly revealed that the SCE and MN rates induced by HgCl2 were alleviated by the presence of D. intestiniforme. In conclusion, the results of the present study revealed for the first time that the lichen D. intestiniforme provided increased resistance of DNA against HgCl2-induced genetic damage on human lymphocytes. © 2012 The Author(s).
URL: http://dx.doi.org/10.1177/0748233711404036
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Keywords: ANTI-ADHESIVE ACTIVITY/ ANTIBACTERIAL ACTIVITY/ HIGH MOLECULAR WEIGHT FRACTION/ LICHENS/ LOW MOLECULAR WEIGHT FRACTION/ SECONDARY METABOLITES
Abstract: Antioxidant, antimicrobial and anti-adhesive activity of six lichens in Central Texas region (.Ramalina celastri (RA), R. stenospora (RS), R. Americana (RA), T. chrysopthalmus (TC), Parmotrema austrosinese (PA) and P. perforatum (PP)) was evaluated. Antioxidant activity was determined by Malondialdehyde (MDA) assay and ABTS radical quenching assay. Antimicrobial and anti-adhesive activity of sterile extracts against P. aeruginosa was determined by Kirby-Bauer disk diffusion assay and ex-vivo skin assay, respectively. The high molecular weight fraction (HMWF) had higher antioxidant activity and quenched 60-75% radicals compared to the low molecular weight fraction (LMWF) which only neutralized 20-40% of the radicals except PA where activity was 79%. All extracts were able to reduce MDA formation by 30-88% except LMWF of RA and PP. None of the extracts had antimicrobial activity in the Kirby-Bauer (KB) disc diffusion assay. All the HMWF were able to reduce adhesion of P. aeruginosa by 30-55% except PP. LMWF from RS, PP, PA and PP reduced bacterial adhesion by 41-54%. Present results suggest that lichens can be an important source for bioactive compounds with potential benefits against oxidative and infectious diseases and warrants further investigation. © 2012 Academic Journals Inc.
URL: http://dx.doi.org/10.3923/jpt.2012.96.103
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Keywords: CONSERVATION MANAGEMENT/ DEGENERATED HEATH/ DISTURBANCE/ FIRE ROTATION/ PRESCRIBED BURNING/ PRINCIPAL RESPONSE CURVES/ RESTORATION
Abstract: Questions: Does stand age influence the direction and rate of post-fire successional dynamics in coastal Calluna heaths and can old degraded heath vegetation be restored through reintroduction of fire? Location: Coastal heaths in the Tarva archipelago, central Norway. Methods: We investigated revegetation dynamics after experimental fires set in young (8 years since last fire) and old (>50 years since last fire) grazed heath stands. A repeated measures design was used, with floristic data recorded in permanent plots in the post-fire successions (n=12) over a 7-year period. The data were analysed using multivariate ordination techniques (PCA, RDA and PRC) and mixed effects models. Results: The age of Calluna stands strongly influenced post-fire succession, different trends due to age explained 10.4% of variation in floristic data. Young heath showed faster succession towards pre-fire community composition than old heath, and this could partially be explained by succession-related factors: young heath had lower cover of mosses and lichens in the pre-burned vegetation, and lower cover of litter early in succession. Young heath had a less pronounced overall community response to fire than old heath. Vegetative regeneration of C. vulgaris was absent in both old and young heath, but Calluna still re-established as the dominant species within 5-7 years in both young and old stands. Regeneration dynamics were also affected by habitat conditions, different trends due to habitat explained 6% of variation. Conclusions: Our study demonstrates that old stands do develop characteristic heathland vegetation and structure after fire, and while potential invasives into the system such as trees and rhizomatous species are present, they do not impair Calluna regeneration or vegetation development towards the target heathland community composition and structure. Further, as our young stands are only in their second fire rotation after restoration, we suggest that characteristic dynamics of managed heathlands can re-establish relatively rapidly, even in severely degenerated sites (>50 years since last fire). Site-specific factors also need to be considered. We conclude that there is restoration potential in old heaths, despite slow dynamics in the first rotation. © 2011 International Association for Vegetation Science.
URL: http://dx.doi.org/10.1111/j.1654-109X.2011.01144.x
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Abstract: In the present report, nutritional requirement for the culture of two lichen species Ramalina nervulosa and Ramalina pacifica were studied in order to enhance their growth rate and antioxidant metabolite production. Extract of R. nervulosa cultured in Bold's basal medium (BBM) showed higher antioxidant activity than R. pacifica cultured in Murashige and Skoog (MS) medium. The lichen species were sub-cultured in standardized nutrient media. R. nervulosa in BBM (1% glucose, 50 ppb asparagines, pH 6.5) yielded 2.76 g biomass with 26.18 mg sekikaic acid, 24.32 mg usnic acid/g dry biomass in a period of 60 days. R. pacifica in MS media (3% sucrose, 100 ppb thiamine, pH 5.9) yielded 3.54 g biomass and 58.92 mg salazinic acid, 40.16 mg usnic acid in the same time period. The standardized culture conditions implemented on bioreactor, R. nervulosa yielded 17.7 g biomass with the production of sekikaic acid 122.8 mg, usnic acid 75.4 mg in 4.5 days. R. pacifica produced 10.3 g biomass along with salazinic acid 200 mg and usnic acid 136.8 mg in the same duration. Lichen secondary metabolites produced in bioreactor showed moderate antioxidant activity; sekikaic acid 42% to 56.4%; salazinic acid 33.6% to 41.9% and usnic acid 19.9% to 29.5%. © 2012 Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i.
URL: http://dx.doi.org/10.1007/s12223-012-0100-2
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Keywords: BIOMOLECULES/ DRUGS/ EXPLOSIVES/ FLUORESCENCE/ INGAAS/ MINERALS/ PORTABLE 1064 NM RAMAN
Abstract: The development of miniaturized Raman instrumentation is in demand for applications relevant to forensic, pharmaceutical and art analyses, as well as geosciences, and planetary exploration. In this study we report on evaluation of a portable dispersive Raman spectrometer equipped with 1064 nm laser excitation. Selected samples from geological, geobiological and forensic areas of interest have been studied from which the advantages, disadvantages and the analytical potential of the instrument are assessed based on a comparison with bench instrumentation and other portable Raman spectrometers using 785 nm excitation. It is demonstrated that the instrument operating with 1064 nm excitation has potential for expanding the number and types of samples that can be measured by miniaturized Raman spectroscopy without interfering fluorescence background emission. It includes inorganic and organic minerals, biomolecules within living lichen and endolithic cyanobacteria as well as drugs of abuse and explosives. © 2011 Elsevier B.V. All rights reserved.
URL: http://dx.doi.org/10.1016/j.saa.2011.10.043
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Keywords: CONVERGENCE, CRYPTIC BIODIVERSITY, LICHENIZED FUNGI, PHYLOGENY, TAXONOMY, THALLUS SIMPLIFICATION
Abstract: The Caloplaca holocarpa group contains members of the family Teloschistaceae with a strongly reduced thallus and conspicuous yellow, orange or red apothecia. In the absence of well-defined thallus characters, taxa of this group must be identified mainly by apothecial characters and are as a result often difficult to separate. The species of this group have been shown not to form a monophyletic entity, with representatives of other Teloschistaceae with more complex thalli intermixed among them. Caloplaca skii and C. syvashica are recognized here as two homogeneous clades with Caloplaca holocarpa-like phenotypes. Caloplaca skii, which is widespread in southern Europe, resembles C. cerinelloides but is distinguished by its smaller and narrower ascospores and by growing predominantly on xerophilous shrubs. Caloplaca syvashica is restricted to shrubs in salt marshes in the northern Black Sea region. It is similar to the British Caloplaca suaedae and Australian C. yarraensis, but differs from both, mainly in ascospore characters. Caloplaca yarraensis is closely related to the new C. syvashica but arguments against their conspecificity are emphasised. A key for epiphytic C. holocarpa-like Teloschistaceae from Europe is provided.
Notes: New species: Caloplaca skii Khodosovtsev, Vondrák & Šoun and Caloplaca syvashica Khodosovtsev, Vondrák & Šoun
URL: http://dx.doi.org/10.1017/S0024282911000636
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Abstract: The levels and distribution of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were investigated in various environmental matrices including soil, sediment, lichen (Usnea aurantiaco-atra) and moss (Sanionia uncinata) from Fildes Peninsula at King George Island and Ardley Island, west Antarctica. In general, PCBs and PBDEs were detected at very low levels in the samples collected during December 2009 to February 2010. The mean concentrations of total PCBs were 410 pg g dry weight (dw) (range 60.1-1436 pg g dw) in soil and sediment, 544 pg g dw (404-745 pg g dw) in lichen and 670 pg g dw (406-952 pg g dw) in moss. The lower chlorinated CBs dominated in all the samples except for the dropping-amended soils from Ardley Island, where hexachlorinated congeners were more abundant. Notably, CB-11 was detected at significant levels, accounting for about 20% of total PCBs in most samples, this higher ratio compared to that in the technical mixture might suggest unidentified sources. Average levels of PBDEs were 24.0 pg g dw (2.76-51.4 pg g dw) in soil and sediment, 14.2 pg g dw (7.51-22.3 pg g dw) in lichen and 15.8 pg g dw (6.54-36.7 pg g dw) in moss. BDE-47 dominated the detected congeners, whereas BDE-99 and 71 were more abundant in the dropping-amended soils from Ardley Island. These results indicated that long-range atmospheric transport could be the main pathway of POPs to King George Island although anthropogenic influence (e.g., from research station, tourism and biotic activities) could also influence the spatial distribution of POPs. © 2012 The Royal Society of Chemistry.
URL: http://dx.doi.org/10.1039/c1ra00462j
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Keywords: ANTIMICROBIAL/ ENDOLICHENIC FUNGUS/ POLYKETIDES/ RADICAL SCAVENGING ACTIVITIES/ ULOCLADIUM SP./ 5' METHOXY 6 METHYL BIPHENYL 3,4,3' TRIOL/ 6 HYDROXY 8 METHOXY 3A METHYL 3A,9B DIHYDRO 3H FURO[3,2 C]ISOCHROMENE 2,5 DIONE/ 6 O METHYLNORLICHEXANTHONE/ 7 HYDROXY 3 (2 HYDROXY PROPYL) 5 METHYL ISOCHROMEN 1 ONE/ 7 HYDROXY 3, 5 DIMETHYL ISOCHROMEN 1 ONE/ ALTENUENE/ ALTENUSIN/ ALTERLACTONE/ AMPHOTERICIN B/ ANTIFUNGAL AGENT/ ANTIINFECTIVE AGENT/ ASCORBIC ACID/ DIHYDROALTENUENE/ FUNGAL EXTRACT/ GENTAMICIN/ GRISEOXANTHONE C/ ISOALTENUENE/ NORLICHEXANTHONE/ POLYKETIDE/ RUBRALACTONE/ SCAVENGER/ UNCLASSIFIED DRUG/ VANCOMYCIN/ ANTIFUNGAL ACTIVITY/ ANTIOXIDANT ACTIVITY/ ARTICLE/ ASPERGILLUS FUMIGATUS/ BACILLUS SUBTILIS/ CANDIDA ALBICANS/ CONTROLLED STUDY/ DRUG ISOLATION/ DRUG STRUCTURE/ ESCHERICHIA COLI/ FUNGUS/ FUNGUS CULTURE/ IC 50/ LICHENS/ METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS/ NONHUMAN/ NUCLEAR MAGNETIC RESONANCE/ PRIORITY JOURNAL/ PSEUDOMONAS AERUGINOSA/ RACEMIC MIXTURE/ ULOCLADIUM/ BACILLUS SUBTILIS/ CANDIDA ALBICANS SC5314/ FUNGI/ METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS/ ULOCLADIUM
Abstract: Two new polyketides, 7-hydroxy-3, 5-dimethyl-isochromen-1-one (1) and 6-hydroxy-8-methoxy-3a-methyl-3a,9b-dihydro-3H-furo[3,2-c]isochromene-2,5-dione (2), along with eleven known compounds, 5?-methoxy-6-methyl-biphenyl-3,4, 3?-triol (3), 7-hydroxy-3-(2-hydroxy-propyl)-5-methyl-isochromen-1-one (4), rubralactone (5), isoaltenuene (6), altenuene (7), dihydroaltenuenes A (8), altenusin (9), alterlactone (10), 6-O-methylnorlichexanthone (11), norlichexanthone (12), and griseoxanthone C (13) were isolated from the culture of the endolichenic fungus Ulocladium sp. Compound 2 was obtained as a racemate with an unprecedented chemical skeleton. The NMR data assignments for 3 and 4 were achieved for the first time. Compounds 1-13 were screened for their antimicrobial and radical scavenging activities. Compound 1 showed some antifungal activity against Candida albicans SC 5314 with IC50 of 97.93 ± 1.12 ?M. Compounds 11-13 showed strong activity against Bacillus subtilis with IC50 in the range of 1-5 ?M. Compound 12 significantly inhibited the growth of methicillin-resistant Staphylococcus aureus with IC50 of 20.95 ± 1.56 ?M. Compounds 9 and 10 showed strong radical scavenging activity in comparison with vitamin C. The plausible biosynthetic pathways for compounds 1, 2, and 4-8 were discussed. Crown Copyright © 2011 Published by Elsevier B.V. All rights reserved.
URL: http://dx.doi.org/10.1016/j.fitote.2011.10.013
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Keywords: CULTURE/ MRNA EXPRESSION/ MYCOBIONT/ ORSELLINIC ACID
Abstract: Usnea longissima has long been used as a traditional medicine in China, India, Turkey, Canada and Europe. This lichen can produce several bioactive compounds that primarily belong to the polyketide family. The enzymes responsible for the production of these compounds are the polyketide synthases, but the biosynthetic processes in lichens are still unclear. In this study, a cultured mycobiont of Usnea longissima was used to isolate and characterize a polyketide synthase gene (UlPKS1). Complete sequence information regarding UlPKS1 (6,468 bp) was obtained by screening a Fosmid genomic library using a 512-bp fragment corresponding to part of the ketosynthase (KS) domain. Sequence analysis of UlPKS1 suggested that it contained features of a non-reducing fungal type I PKS with a starter unit of ACP transacylase (SAT), ketosynthase (KS), product template (PT), acyl carrier protein (ACP) transacylase, acyltransferase (AT) and thioesterase (TE) domain, and had five intervening introns. The domain organization of UlPKS1 (SAT-KS-AT-PT-ACP-ACP-TE) was quite similar to that of aromatic PKSs, and phylogenetic analysis showed that UlPKS1 belonged to the clade of lichenized fungal non-reducing PKS. RT-PCR analyses revealed that the expression of UlPKS1 was down-regulated by glycine and high concentrations of sorbitol, inositol and fructose and up-regulated by sucrose and glucose. Here, we introduce a non-reducing PKS gene in the lichen-forming fungus U. longissima, with a domain structure similar to the structure of orsellinic acid synthase A (OrsA) which is required for orsellinic acid biosynthesis in Aspergillus nidulans. © 2011 German Mycological Society and Springer.
URL: http://dx.doi.org/10.1007/s11557-010-0730-1
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Keywords: CARBON STORAGE/ CROWN HUMUS/ DEAD ORGANIC MATTER/ ECUADOR/ EPIPHYTES/ MAXIMUM WATER STORAGE CAPACITY/ SUCCESSION/ TOPOGRAPHIC HETEROGENEITY/ BASAL AREA/ BIOMASS/ BRYOPHYTE/ CANOPY ARCHITECTURE/ EPIPHYTE/ FLUX MEASUREMENT/ FOREST DYNAMICS/ HETEROGENEITY/ LICHEN/ MICROCLIMATE/ MONTANE FOREST/ NUTRIENT AVAILABILITY/ SLOPE/ SPATIAL ANALYSIS/ STAND STRUCTURE/ SUCCESSION/ TOPOGRAPHY/ TROPICAL ENVIRONMENT/ TROPICAL FOREST/ ECUADOR
Abstract: The spatial heterogeneity of tropical forest epiphytes has rarely been quantified in terms of biomass. In particular, the effect of topographic variation on epiphyte biomass is poorly known, although forests on ridges and ravines can differ drastically in stature and exposure. In an Ecuadorian lower montane forest we quantified epiphytic biomass along two gradients: (1) the twig-branch-trunk trajectory, and (2) the ridge-ravine gradient. Twenty-one trees were sampled in each of three forest types (ridge, slope, ravine positions). Their epiphytic biomass was extrapolated to stand level based on basal area-epiphyte load relationships, with tree basal areas taken from six plots of 400 m2 each per forest type. Our results document the successional addition and partial replacement of lichens by bryophytes, angiosperms and finally dead organic matter along the twig-branch-trunk trajectory. Despite having the highest tree basal area, total epiphytic biomass (mean ± SD) of ravine forest was significantly lower (2.6 ± 0.7 Mg ha) than in mid-slope forest (6.3 ± 1.1 Mg ha) and ridge forest (4.4 ± 1.6 Mg ha), whereas maximum bryophyte water storage capacity was significantly higher. We attribute this pattern to differences in forest dynamics, stand structure and microclimate. Although our study could not differentiate between direct effects of slope position (nutrient availability, mesoclimate) and indirect effects (stand structure and dynamics), it provides evidence that fine-scale topography needs to be taken into account when extrapolating epiphytic biomass and related matter fluxes from stand-level data to the regional scale. © Copyright Cambridge University Press 2011.
URL: http://dx.doi.org/10.1017/S0266467411000526
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Abstract: The extent of codispersal of symbionts is one of the key factors shaping genetic structures of symbiotic organisms. Concordant patterns of genetic structure are expected in vertically transmitted symbioses, whereas horizontal transmission generally uncouples genetic structures unless the partners are coadapted. Here, we compared the genetic structures of mutualists, the lichen-forming fungus Lobaria pulmonaria and its primary green-algal photobiont, Dictyochloropsis reticulata. We performed analysis of molecular variance and variogram analysis to compare genetic structures between symbiosis partners. We simulated the expected number of multilocus-genotype recurrences to reveal whether the distribution of multilocus genotypes of either species was concordant with panmixia. Simulations and tests of linkage disequilibrium provided compelling evidence for the codispersal of mutualists. To test whether genotype associations between symbionts were consistent with randomness, as expected under horizontal transmission, we simulated the recurrence of fungal-algal multilocus genotype associations expected by chance. Our data showed nonrandom associations of fungal and algal genotypes. Either vertical transmission or horizontal transmission coupled with coadaptation between symbiont genotypes may have created these nonrandom associations. This study is among the first to show codispersal and highly congruent genetic structures in the partners of a lichen mutualism. © 2012 The American Phytopathological Society.
URL: http://dx.doi.org/10.1094/MPMI-03-11-0081
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Abstract: Four new ent-kaurane diterpenoids, geopyxins A-D (1-4), were isolated from Geopyxis aff. majalis, a fungus occurring in the lichen Pseudevernia intensa, whereas Geopyxis sp. AZ0066 inhabiting the same host afforded two new ent-kaurane diterpenoids, geopyxins E and F (5 and 6), together with 1 and 3. The structures of 1-6 were established on the basis of their spectroscopic data, while the absolute configurations were assigned using modified Mosher's ester method. Methylation of 1-3, 5, and 6 gave their corresponding methyl esters 7-11. On acetylation, 1 and 7 yielded their corresponding monoacetates 12 and 14 and diacetates 13 and 15. All compounds were evaluated for their cytotoxic and heat-shock induction activities. Compounds 2, 7-10, 12, 14, and 15 showed cytotoxic activity in the low micromolar range against all five cancer cell lines tested, but only compounds 7-9, 14, and 15 were found to activate the heat-shock response at similar concentrations. From a preliminary structure-activity perspective, the electrophilic ?,?-unsaturated ketone carbonyl motif present in all compounds except 6 and 11 was found to be necessary but not sufficient for both cytotoxicity and heat-shock activation. © 2012 The American Chemical Society and American Society of Pharmacognosy.
URL: http://dx.doi.org/10.1021/np200769q
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Keywords: COHESION SPECIES/ LICHENS/ SPECIES DELIMITATION/ USNEA
Abstract: Species delimitations in the predominantly Antarctic and South American group of neuropogonoid species of the lichen-forming fungal genus Usnea are poorly understood. Morphological variability has been interpreted as a result of harsh ecological conditions, but preliminary molecular data have led to doubts about the current species delimitations in these lichenized fungi. We examined species boundaries using a phylogenetic approach and a cohesion species recognition method generating haplotype networks and looking at associations of phenotypic characters with clades found in the networks. In addition, we estimated gene flow among detected clades and currently circumscribed species. We identified several clades that were significantly associated with phenotypic characters, but did not necessarily agree with current species circumscriptions. In one case (U. aurantiaco-atra/U. antarctica), network analysis and the estimation of gene flow provided no evidence of distinct species. The distinctness of another species pair (U. subantarctica/U. trachycarpa) remains dubious, showing evidence for gene flow among currently accepted species. © 2011 Gesellschaft für Biologische Systematik.
URL: http://dx.doi.org/10.1007/s13127-011-0066-y
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Keywords: ACANTHOLICHEN/ CENSUS OF GALAPAGOS BIODIVERSITY/ CORA/ CYPHELLOSTEREUM/ DICTYONEMA/ GALAPAGOS LICHEN INVENTORY
Abstract: As part of an ongoing comprehensive inventory of Galapagos lichens, a first assessment of the morphology and anatomy of basidiolichens from the archipelago is presented here. It is the basis for further studies of the taxonomy, ecology and biogeography of this poorly known group of lichens. Four genera, all in Hygrophoraceae, can be distinguished: Acantholichen, Cora, Cyphellostereum and Dictyonema. Both Acantholichen and Cora are characterized by chroococcoid cyanobionts and a heteromerous thallus with a distinct upper cortex and photobiont layer. The monotypic Acantholichen pannarioides is entirely composed of small, branched, inflated squamules that appear densely pruinose because their cortical hyphae bear characteristically swollen, densely spinose end cells (acanthohyphidia); this species has never been observed fertile. The common Cora glabrata is foliose, forming large, radially zonate, conch-like, often tiled thalli, when fertile with circular lines of basidiocarps on its lower side. Dictyonema is distinguished by filamentous cyanobionts and distinctly filamentous thalli that are homomereous (i.e., not distinctly layered); all species of Dictyonema s.str. have trichomes (filamentose cyanobacterial photobionts) closely enveloped by fungal cells of a jigsaw pattern. In D. sericeum thallus filaments (i.e., individual fibrils) aggregate to form shelf-like structures similar in appearance to polyporoid bracket fungi; basidiocarps develop in irregular patches on the lower side of these shelves. In contrast, fibrils of D. schenkianum grow encrusting their substrate with irregularly to suberect trichomes, occasionally bearing basidiocarps dispersed across the thallus. Two other species in Galapagos show adpressed growth form and are described here as new: Dictyonema pectinatum, which is characterized by large parallel fibrils with paler, papillate tips, and D. galapagoense, characterized by thin trichomes of more squarrish elongate cells. The genus Cyphellostereum is represented by two species: the newly described C. imperfectum and an unnamed Cyphellostereum sp., both phenotypically similar to free-living cyanobacterial filaments. Cyphellostereum imperfectum has narrow photobiont filaments with irregular hyphal sheath leaving interspaces; macroscopically it shows a bluish green thallus with a distinct prothallus. Cyphellostereum sp. has a rather uncommon basidiolichen appearance: thin sctytonematoid fibrils surrounded by straight fungal cells forming shiny tufts. The new combination Cyphellostereum nitidum is also proposed. The ecology and taxonomy of Galapagos basidiolichens is briefly discussed and a key and short descriptions of all species are presented. © Kevin D. Hyde 2011.
URL: http://dx.doi.org/10.1007/s13225-011-0133-x
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Keywords: INSECTICIDAL EFFECTS/ LICHEN EXTRACTS/ SITOPHILUS GRANARIUS/ USNEA LONGISSIMA
Abstract: Two secondary metabolites (diffractaic acid & usnic acid) and extract of a lichen species, Usnea longissima Ach. were tested against adults of Sitophilus granarius (L.) on Petri dishes. After exposure, mortality of the adults was determined at 24th, 48th and 96th h. The results showed that secondary metabolites and extract of U. longissima have an insecticidal effect on adults of Sitophilus granarius (L.) in comparison with controls. The insecticidal effect was influenced by the concentrations of the extracts and the exposure time. Higher concentrations and longer exposure time resulted in maximum toxicity on S. granarius. Treatment with extract and lichen compounds of U. longissima pointed out equal mortality against adults of S. granarius. The mortality rates after 96 h of treatment with the maximum concentration (10 mg mL) of U. longissima extract, diffractaic acid and usnic acid were determined as 98.98, 91.91 and 94.94% for S. granarius, respectively. However, there was no mortality in the controls. The mortality rates after 96 h of treatment with the 10 mg mL-1 in concentrations of the extract of U. longissima were established and the highest mortality rate was found against S. granarius with 98.98%. © 2012 Friends Science Publishers.
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-84858320610&partnerID=40&md5=9222056c6e8f8812911023fde7c31d35
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Keywords: BIOLOGICAL WEATHERING/ BIOTIC WEATHERING/ CHEMICAL DENUDATION/ LICHEN/ WEATHERING FLUX/ XANTHOPARMELIA PLITTII
Abstract: It has long been suspected that lichens increase the rate of physical and chemical weathering of rock surfaces, thus playing a role in biogeochemical cycles. However, the relative weathering flux of elements from lichen-colonized rock versus bare rock has been minimally studied; previous attempts to quantify the effect of lichen-cover on weathering have focused disproportionately on evidence from altered weathering rinds on basalt. Here, in a field experiment on hornblende granite in New Jersey (USA), we measured the cumulative waterborne net efflux of five elements over 31days and six rain events, from multiple constructed miniature watersheds consisting of either lichen-covered or exposed bare rock. On average, lichen-covered watersheds showed approximately double the silicon flux, and three times the calcium and magnesium flux compared to bare-rock. Additionally, efflux of these elements was higher in lichen-covered watersheds across all six rain events. This suggests that lichens do indeed promote increased chemical weathering compared to bare rock, thus likely increasing sequestration of atmospheric CO2 under equal conditions of atmospheric pCO2, temperature, and rainfall. It was also observed that lichen-covered watersheds showed a 50% reduction in iron flux, and had a greater ratio of calcium and magnesium to silicon flux compared to bare-rock watersheds. The possible causes of these patterns are discussed. © 2011 Elsevier B.V.
URL: http://dx.doi.org/10.1016/j.chemgeo.2011.10.009
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Current date: 2026.03.03.OK