ABLS Meeting 2007 Xalapa, México |  | ||
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ABSTRACTS OF ORAL PRESENTATIONS
CARTER, BENJAMIN E. University of California, Berkeley, Integrative Biology, 3060 Valley Life Sciences Bldg., Berkeley, CA 94720, USA.
Using floristic data to assess spatial patterns of moss traits in a heterogeneous landscape: a case study from California
The ability of mosses to exist in their relative niche spaces is related to, among other factors, the morphological, physiological and reproductive traits that allow them to withstand environmental pressures within those niches. These ecological traits can be examined in a spatial context using floristic data to begin to uncover how the traits themselves are related to the evolutionary and ecological determinants of the flora. Shifting focus from the geographic distribution of taxa to the geographic distribution of traits is a potentially productive route toward the elucidation of relative importance of these traits in different environments. With relatively high diversity and high spatial heterogeneity, the moss flora of California provides a good case study for the utility of such an approach. Here I present preliminary findings of trait patterns and correlations at the scale of ten ecologically defined subregions comprising California. Patterns at this resolution can be used as a starting point both for analyses at multiple spatial scales, and analyses incorporating phylogeny into the interpretation of spatial trait relationships.
DELGADILLO-MOYA, CLAUDIO Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, Delegación Coyoacán, 04510 México, D.F.
Diversity and distribution of the Central American moss flora
Central America possesses a diverse moss flora. Its estimated 1,070 species and varieties have multiple geographical relationships and origins. Present species diversity may be explained by the geographical situation of Central America between two major continental masses, topographic features that include major mountain systems, and a complex geological history. Emphasis is placed here on the role of the Neovolcanic Belt of central Mexico and the northern Andes of Colombia that have modified species migration patterns. Both ranges have favored moss dispersal at high elevations, but have reduced floristic flow in the lowlands. Under their influence, the Central American moss flora has become distinctly different from the rest of the tropical South American flora, especially that of Brazil.
EQUIHUA, CLEMENTINA Departamento de Ecología Evolutiva, Instituto de Ecología, UNAM. Ap. Postal 70-273, 04510, México, D.F. MEXICO.
Genetic variation of Bryopteris filicina in the Selva Lacandona of Chiapas, Mexico
The biology of the epiphytic moss Bryopteris filicina in the rain forest of the Selva Lacandona, Chiapas, Mexico is poorly known. Bryopteris filicina is dioecious and frequently propagates by means of vegetative propagules such as cladia. In order to determine the genetic variation of the species in the region, 285 samples were obtained from three sites in the Selva Lacandona: Chajul, Loma Bonita and Ixcán. Three samples from each tree trunk at three height levels along a 2 m Canfield line: highest, medium and lowest registered points on each trunk, for a total of 95 trees sampled. Air dried material was used to extract DNA. Random Amplified Polymorphic DNAs (RAPDs) were used as molecular markers for this analysis. Primers F10 and F14 were used for DNA amplification. Genetic variation is analyzed at three levels: 1) within patches (highest, medium and lower points), 2) among trees and 3) among sites. Preliminary results indicate a high degree of genetic similarity between the populations of Chajul, Loma Bonita and Ixcán. These results are consistent with findings in other studies where epiphytic bryophytes have been found to show little genetic differentiation.
*EQUIHUA, CLEMENTINA1 and MIGUEL EQUIHUA2 1Departamento de Ecología Evolutiva, Instituto de Ecología, UNAM. Ap. Postal 70-273, 04510, México, D.F. MEXICO; 2Instituto de Ecología, A.C., Ap. Postal 63, 91000 Xalapa, Veracruz, MEXICO
Spatial distribution of Bryopteris filicina on tree trunks of the Selva Lacandona, Chiapas, Mexico
Bryopteris filicina is an epiphytic moss in neotropical rainforest trees. The objective of this study was to describe the spatial distribution of B. filicina at two spatial scales: 1) along standing tree trunks in the Lacandona Forest of Chiapas, Mexico, and 2) among three sites with contrasting degrees of conservation. We expected to find larger Bryopteris
filicina populations in well-preserved conditions compared to disturbed areas, and on non-smooth trunk surfaces, rather than on smooth trunks. A modified Canfield line protocol was used to quantify the distribution of B. filicina. This species was found on a total of 142 trees, but it was over-represented on Ampelocera hottlei, Brosimum alicastrum and Guarea glabra, three species that are common in the area. Height within the range studied (0–2m), bark texture, and orientation are good predictors of the presence of B. filicina between the studied sites in the Selva Lacandona. Bryopteris filicina tends to be more abundant on trees with smooth texture (as in A. hottlei and B. alicastrum), oriented towards north in Chajul and Loma Bonita and south in Ixcán.
GARCÍA-AVILA, DENEB Km 2.5 carretera antigua a Coatepec 351, Congregación El Haya. Depto. Biodiversidad y Sistemática, Instituto de Ecología, AC., 91070, Xalapa, Veracruz. México
The molecular phylogeny of the family Thuidiaceae (Bryophyta): insights about inner relationships
The family Thuidiaceae comprises 16 genera and 72 valid species, according to the most recent circumscription. Previous phylogenetic analyses, based on molecular characters, retrieved Thuidiaceae as monophyletic, sensu Tow (2001), except the species Hylocomiopsis ovicarpa and found Leskeaceae, Rhytidiaceae and Amblystegiaceae as sister groups of Thuidiaceae. The present analysis was based on rps4 and rbcL. Outgroups was those found in the previous analysis as sister group of Thuidiaceae: Leskeaceae, Rhytidiaceae and Amblystegiaceae. I did analyze both genes separately and combined. The analysis of the rps4 gene plus rps4-trnS intergenic spacer, based on 22 in-group and two out groups, recovered five separate clades: (Leskea, Rauiella), (Actinothuidium, (T. cymbifolium, T. tamariscinum, T.delicatulum)), ((Aequatoriella, P.siphotheca), T.furfurosa, (P.chenagonii, T.sparsa)), (B.molkenboeri, H. blandowii), (P. versicolor, P. velatum). The remaining taxa were collapsed in a polytomy with these five clades. The combination of both rps4 and rbcL retrieved 2 EPT based on 108 informative characters and high support values. The genera Thuidium and Pelekium were not monophyletic and, again, Leskea was nested inside a Thuidiaceae clade comprising Haplocladium and Rauiella.
GLEW, KATHERINE University of Washington, Herbarium, Lichen Collection, UW-HHMI Visit Biology Program, Box 355320, Seattle, WA 98195
Floristic surveys of lichens on the small islands in the San Juan Archipelago, Washington State
During the years of 2005 and 2006, the University of Washington Herbarium organized collection forays to the small islands of the San Juan Archipelago. These forays were funded by Washington Native Plant Society, University of Washington Herbarium Endowment Fund, National Science Foundation, and private donors. The purpose of the forays was to determine the lichen, plant, and bryophyte diversity of the smaller islands, often inhabited only by animals or occasional owners. Several of the islands are marine parks for day use only. There are 172 islands in the San Juan Archipelago and it was expected that the new collections would fill some of the voids in our knowledge regarding the lichen species found in the islands. Lichens from the 4 larger islands (San Juan, Orcas, Shaw, Lopez) were collected in 1998, resulting in over 170 species. To date, 25 small islands have been surveyed for lichens, with over 1,330 collections and 70 species. Several of the genera prefer the small rocky islands inhabited by marine birds, showered in nitrogenous waste. Caloplacas display their highest diversity along the shoreline. Thelomma mammosum is common on these rocky islands but rarely seen on the larger islands. Niebla cephalota was frequently found on conifers and small woody shrubs just above the beach. Flavoparmelia caperata is occasionally found amongst vegetation and exposed rocks above the shore. A new species of Sagiolechia was found on several of the islands, intermittently on oak and driftwood. It is anticipated that this project will facilitate the development of priorities and policies for protecting these small island ecosystems.
HARRIS, ERIC S.J. University Herbarium, and Department of Integrative Biology, 3060 Valley Life Sciences Building, Berkeley, California 94720, USA
Bryophytes used in traditional Chinese medicine
There is a long history of bryophytes used in Traditional Chinese Medicine (TCM). Polytrichum and Bryum appear in the literature of TCM as early as Li ShiZhen’s famous Compendium of Materia Medica published in the 16th century, and some authors have made note of medicinal bryophytes even earlier in Chinese history. Contemporary TCM encyclopedias report as many as 50-60 species of bryophytes with medicinal uses, the most reported for any country in the world. Although some of these bryophytes may not find current or widespread use, one of the most commonly used bryophytes with contemporary medicinal use is the moss Rhodobryum giganteum. This moss is a popular medicinal herb in Southwest China and can be found in a variety of places ranging from the village market to airport souvenir shops. Rhodobryum is generally used to treat minor heart problems, but there exists some variation in the way that it is used, the herbs it is prescribed with, and the types of symptoms it is used for. However, the use of Rhodobryum is also standardized to some extent through the publication of herb books used by many medicinal practitioners in Southwest China.
HAUCK, MARKUS Albrecht von Haller Institute of Plant Sciences, Dept. Plant Ecology, University of Göttingen, Untere Karspüle 2, D-37073 Göttingen, Germany.
New insights into the pollution tolerance of lichens
Lichens are long since known for their sensitivity to acidic precipitation containing dissolved sulphur dioxide (SO2). Further, some lichens are known to be sensitive to heavy metals, while other species can accumulate large amounts without severe damage. Though a large body of literature has been accumulated dealing with the pollution tolerance of lichens, relatively little is known about mechanisms causing different tolerances of different lichen symbioses. Current results show that the tolerance of lichens to sulphuric, acidic precipitation primarily depends on the hydrophobicity of the thallus surface. SO2-tolerant lichens have a strongly hydrophobic surface (similar to the lotus flower), whereas the thalli of lichens sensitive to SO2 are hydrophilic. The tolerance of lichens to SO2 is further controlled by their content of lichen substances. Metal homoeostasis in lichens is also influenced by the production of lichen substances, as lichen substances selectively control the adsorption of metal ions at cation exchange sites and their intracellular uptake. The physico-chemical basis of these effects is not yet clear. Moreover, the tolerance of lichens to transition metals depends on their ability to immobilize potentially toxic metal ions in intracellular polyphosphate bodies and phytochelatines. Surface hydrophobicity is thought to exert an additional effect on the metal tolerance of lichens, as it generally reduces the intensity of the contact of the lichen thallus to aqueous solutions.
HERRERA-CAMPOS, MARÍA ANGELES Instituto de Biología, UNAM, Departamento de Botánica, Apdo. Postal 70-233, Cd. Universitaria, Coyoacán, México, D. F. 04510 México.
Recent studies of lichens in Mexico
Mexico, as the third ranked of the mega-diversity countries of the world (following Brazil and Colombia), possesses all the major biological communities in the world, housing 12% of the world’s flora. However, the lichen diversity of these communities is largely unknown, except for the Sonoran Desert region and adjacent areas of the northwest. Until the extensive collections of Frère Arsène and the publications of Bouly de Lesdain (1914, 1929 & 1933), studies on Mexican lichens consisted of very scarce or sporadic mentions in the literature, mainly the product of occasional collecting by European lichenologists. Later, in 1956, Imshaug’s Catalogue appeared, but of its 1,000 specific names nearly half were not valid. In 1988, a first revised catalogue was assembled at ASU and by 1996 it was updated by Ryan et al., providing 935 valid species names. This number continuously increased in the following years with the development of the project on the Sonoran Desert Region conducted by Dr. Thomas Nash III at ASU. The publication of The Lichen Flora of the Greater Sonoran Desert in 2000 & 2004 and further studies raised to over 1,300 the lichen species for Mexico. Although for several decades floristic and taxonomic studies were focused mainly on macrolichens by local mycologists and national and international lichenologists, a study on foliicolous lichens of the southeastern tropical rainforest was conducted in collaboration with Dr. Robert Lücking. A list of 300 species was produced. Besides the inventory, general biogeographic affinities with other Neotropical countries were shown, as well as the utility of these organisms as indicators of vegetation gradients. In cooperation with various national institutions, investigations with different approaches have also been done: analysis of the potential distribution of Usnea species using predictive ecogeographical maps; the study of the effects of forest management in lichen communities; and air pollution biomonitoring. Currently, at Instituto de Biología, UNAM, several collaborative projects are being carried out, among them: Parmeliaceae of Mexico; Lichen crusts from humid tropical forests of Mexico; and The genus Usnea in Mexico. These involve the participation of worldwide known lichenologists from American and European universities and research institutes. These studies will allow different ecogeographical and biogeographical analysis of Mexico’s lichen diversity; will facilitate the coordination with on-going molecular investigations; and will provide essential information for the identification of critical sites for conservation as well as for future pollution investigations. Also, they will contribute to the consolidation of a Mexican group of lichenologists.
*HODKINSON, BRENDAN P. and FRANÇOIS LUTZONI Duke University, Department of Biology, Box 90338, Durham, North Carolina 27708, USA.
Non-photosynthetic bacteria and the lichen symbiosis
Common knowledge dictates that the lichen thallus is formed solely by a fungus that develops a symbiotic relationship with an alga and/or cyanobacterium. However, many lichens are able to grow on extremely nutrient-poor substrates, raising the question of how they are able to maintain themselves without a substantial source of nitrogen and other crucial micronutrients. Though non-photosynthetic bacteria have never been accepted as an essential part of the lichen symbiosis, the metabolic processes that they perform may play a vital role in providing the fungi and algae with necessary nutrients and facilitating interactions between them. Here we present evidence that certain non-photosynthetic bacteria may be crucial in the maintenance and evolution of the lichen symbiosis. As part of this study, we have developed several PCR primer sets that target 16S ribosomal sequences of non-photosynthetic eubacteria, but exclude sequences derived from chloroplasts and cyanobacteria. PCR-based surveys were conducted using a fast new method known as Heterogeneous Amplicon Pool Sequence Analysis (HAPSA). Our analyses have revealed a number of interesting and potentially important bacterial lineages associated with lichens. We present several hypotheses concerning the role of non-photosynthetic bacteria in the development, maintenance, and evolution of lichen thalli in nature.
*KAYES, LORI1, PAUL ANDERSON2 and KLAUS PUETTMANN1 1Oregon State University, Department of Forest Science, 321 Richardson Hall, Corvallis, Oregon 97331-2902, USA; 2USDA Forest Service, Pacific Northwest Research Station, 3200 NW Jefferson Way, Corvallis, OR, 97331, USA.
Early response of terrestrial cryptogam communities to post-fire restoration treatments in southwestern Oregon
What are the effects of post-fire restoration of terrestrial cryptogam communities? Research indicates that fire drastically alters the species composition and abundance of terrestrial cryptogam communities and shifts the community composition to disturbance-adapted species. These disturbance-adapted cryptogam species have a ubiquitous distribution and are often the first colonizers following all kinds of disturbance worldwide. Little research investigates community composition of terrestrial cryptograms or how management practices and environmental factors influence these cryptogam communities. Restoration treatments were implemented in severely burned plantations following the Timbered Rock fire of southwestern Oregon to examine effects of artificial conifer regeneration and vegetation control (shrub cutting and the scalping of all vegetation around the planted seedlings) on multiple factors. Since early post-fire cryptogam communities are adapted to disturbance, we hypothesized that post-fire restoration treatments would not alter the terrestrial cryptogam community composition. Using nonmetric multidimensional scaling, we first examined the environmental factors that best explained the cryptogam community composition. The two strongest gradients in cryptogam community composition were related to percent live and/or percent dead overstory basal area and bryophyte abundance. Using multi-response permutation procedure, we compared terrestrial cryptogam community composition among a range of restoration treatments and for paired sites with contrasting edaphic characteristics posing relatively harsh or moderate growing conditions (site quality). Contrary to our hypotheses, vegetation control altered the cryptogram community composition but the magnitude of the effect varied by site quality. Site quality, legacy components and fire severity all appear to contribute to cryptogam community composition following wildfire and restoration.
*LEAVITT, STEVEN D. and LARRY L. ST.CLAIR Department of Biology and the M.L. Bean Life Science Museum 290 MLBM, Brigham Young University, Provo, UT 84602, U.S.A.
Chemical and morphological relationships among Xanthoparmelia species on Boulder Mountain, Aquarius Plateau, Utah, USA
The origin of vagrant lichens has been widely disputed. It has been proposed that vagrant lichens may be detached, environmentally modified morphs of attached taxa or genetically distinct, predominantly asexually reproducing species. In this study, secondary chemistry was used to compare saxicolous-attached and vagrant Xanthoparmelia species on a high mountain plateau in southern Utah, USA. Secondary compounds were isolated using one-dimensional thin-layer-chromatography, and spots common to three solvent systems were used to define all chemotypes. The results documented the presence of 22 unique Xanthoparmelia chemotypes among the populations at the study sites. Thirty-one percent of the attached Xanthoparmelia species had chemotypes identical to the most common vagrant – X. chlorochroa, suggesting a close relationship between these morphologically distinct taxa. In addition, morphological and chemical data further suggest that a significant proportion of the unattached Xanthoparmelia population, ranging from 1.1 % to 18.4 % across our study area, is composed of individuals that become detached from rock substrates and survive as vagrant forms. We are currently conducting molecular studies in order to further define the dynamics of this relationship.
*LUMBSCH, H. THORSTEN1, ARMIN MANGOLD1, ROBERT LÜCKING1 and MARIA P. MARTIN2 1The Field Museum, Department of Botany, 1400 S. Lake Shore Drive, Chicago, Illinois 60605, USA; 2Department of Mycology, Real Jardin Botanico, CSIC, Plaza de Murillo 2, 28014 Madrid, Spain.
Phylogenetic studies on Thelotremataceae using ribosomal and RPB1 sequence data reveal polyphyly of the family and most of its genera
Thelotremataceae is a family of predominantly tropical crustose lichens belonging to the order Ostropales. The circumscription of the family and distinction of genera within the family have been disputed. Recently, phylogenetic analyses suggested that its distinction from Graphidaceae is dubious, but only limited taxa of Thelotremataceae sequences were available. The generic concept in the family has traditionally relied on schematic use of few morphological characters, being ascospore color and septation in classical classifications, and exciple type and pigmentation in more recent classification. Recently, numerous new genera were distinguished in the family based on morphological characters. In an attempt to address the issue of the circumscription of the family and genera within the group, we assembled sequence data of the nuclear LSU and mitochondrial SSU ribosomal DNA, and the protein-coding RPB1 gene. Phylogenetic analyses of these data show that monophyly of Thelotremataceae is rejected and distinction from Graphidaceae is not possible. Further, all of the traditionally circumscribed genera, and several of the currently distinguished genera were found to be non-monophyletic.
MISHLER, BRENT D. University Herbarium, Jepson Herbarium, and Dept. of Integrative Biology, University of California, Berkeley, CA 94720, USA.
The Physcomitrella Genome Project and its uses in bryology and beyond.
A draft sequence of the complete nuclear genome of the moss Physcomitrella patens was completed and made available to the public in April 2007. It can be browsed, searched, and downloaded at the Joint Genome Institute's Genome Portal (http://genome.jgi-psf.org/Physcomitrella). This information will provide benefits for many areas of bryology, ranging from molecular biology to population genetics, development, systematics, ecology, and evolution. One of the fastest growing areas of biology is comparative genomics. A recent synthesis of phylogenetics and genomics – two fields once estranged – is beginning to form a new field that could be called "phylogenomics." There are benefits in both directions: new comparative genomic data will greatly increase the accuracy of phylogenetic trees, while cross-genome comparisons using phylogenetic trees will provide insights into many open functional questions. For the former purpose, new genes can be sought for nucleotide sequence comparisons, as well as fundamentally new kinds of structural genomic characters such as inversions, translocations, losses, duplications, and insertion/deletion of introns. For the latter purpose, DNA sequences, genome structural features, phenotypes, and functions can be mapped onto phylogenetic trees, allowing two major types of inference. Close sister-group comparisons between lineages differing in a critical phenotype (e.g., desiccation or freeze tolerance) can allow a quick narrowing of the search for genetic causes. Ancestor-descendent reconstructions allow dissection of a complicated, evolutionarily advanced genotype/phenotype complex (e.g., development of the angiosperm flower), by tracing its components back to simpler ancestral systems, thus leading to quicker understanding. As an example of the essential role phylogenetics plays in understanding the composition of genomes as well as their function and evolution, I will examine the process of "annotation" of a new genome such as Physcomitrella. The phylogenetic concepts of orthology and paralogy are key to understanding gene family evolution. In turn, knowledge of gene family evolution is necessary to answer important questions about where new genes come from and how divergence in function happens as a lineage becomes more complex. Physcomitrella is perfectly placed phylogenetically to serve as a point of comparison for angiosperms.
*MISHLER, BRENT D.1, and KIRSTEN M. FISHER2 1University Herbarium, Jepson Herbarium, and Dept. of Integrative Biology, University of California, Berkeley, CA 94720, USA. 2National Evolutionary Synthesis Center (NESCent), Durham, NC 27705, USA.
An exploration of the Phylocode using the moss clade Calymperaceae.
Evolution is the single most powerful process underlying biological diversity, and results in life being organized as a hierarchy of nested monophyletic groups. Thus, most systematists now feel that the formal biological classification system should be used to name such groups. However, there still remains controversy about how exactly to do this. Many researchers are resigned to using the existing codes of nomenclature to name monophyletic groups, but two major problems arise when attempting this (both stemming from the pre-evolutionary historical origin of these codes): (1) the impossibility of precisely specifying which clade is being named using only one type specimen, and (2) the incomparability of taxonomic ranks under a phylogenetic worldview. The developing Phylocode is an attempt to address these problems (while retaining many other unproblematic aspects of the current codes) to produce a truly phylogenetic classification system. Perhaps most controversial, on all sides of the debate, is the terminal level (species). Curiously, many advocates of rank-free phylogenetic classification have wanted to retain the species rank as a special case, probably because the species concept is so ingrained and comfortable in current thinking. However, all the arguments that can be massed against Linnaean ranked classification can be brought to bear against the species rank as well. As difficult as it is to overthrow ingrained habits of thinking, logical consistency demands that all levels in the classification should be treated alike. We argue that the species rank must go the way of all others. Biological classification should be a set of nested, named groups for inter-nested clades at all levels. We stop naming groups at some point approaching the tips of the phylogeny because we don't have solid evidence for monophyly at the present stage of knowledge. This may be due to rampant reticulation going on below some point, or simply lack of appropriate markers for distinguishing finer clades. We examine the applicability of the Phylocode for bryology at several different hierarchical levels using the moss clade Calymperaceae. We show how rank-free phylogenetic taxonomy can be applied efficiently at all levels, even the terminal level, by naming taxa with unranked (but hierarchically nested) uninomials. Finally, we explore the practical implications of eliminating taxonomic ranks (including species) for such areas as education, ecology, evolution, and conservation, and conclude that these purposes are better served by this move.
*NASH, THOMAS H., III1 and MARIA ANGELES HERRERA-CAMPOS2 1School of Life Sciences, Arizona State University, Box 874501, Tempe, AZ 85287-4501 USA; 2Instituto de Biologia, Botanica y Micologia, Universidad Nacional de Mexico, Mexico City, D.F.
The lichens of Sonora, the heart of the Sonoran Desert region
The state of Sonora lies in the heart of the Sonoran Desert, as defined by Schreve and also includes a significant portion of the Sierra Madre Occidental, which is largely volcanic in origin. As part of the greater Sonoran Desert Lichen Flora project, we have collected extensively in Sonora, and the collections have been determined by over 80 experts from 20 countries. Herein we have compiled a checklist of nearly 500 species for the state, based on records held at ASU and also compiled in the three volume flora (Nash et al. 2002, 2004, 2007). Below 1000 m, interior desert lichens dominate the flora, but along the southern coast fog zone lichens are found. Fog and/or dew fall is not as frequent as occurs along the west coast of Baja California, but nevertheless over 25 of the typical fog zone lichens found in Baja California also occur in Sonora. In the eastern part of the state elevations rise to over 2000 m, and in this region macrolichens occur abundantly in the oak and pine forests, as also occurs in southeastern Arizona. In the very southern part of the state subtropical elements can be found. If one considers other lichens known from areas adjacent to Sonora (western Chihuahua, northern Sinaloa, and southern Arizona), then we estimate that additional lichen species could readily be found in Sonora, perhaps increasing the total species count by 10%.
PETERSON, ERIC B. Nevada Natural Heritage Program, Department of Conservation and Natural Resources, 901 South Stewart Street, suite 5002, Carson City, NV 89701-5245, USA.
Biological soil crusts and the invasive annual grass Bromus tectorum – a case of mutual exclusion.
The intermountain west is characterized by high deserts dominated by shrublands, especially sagebrushes (Artemisia spp.). Biological soil crusts are thought to have been a keystone component of these arid ecosystems, performing ecosystem services related to erosion and soil hydrology. Land use has removed biological soil crusts from much of their presumed historic extent. Native annual grasses were a minor component of the vegetation; however, several exotic annual grasses have proliferated in recent decades. These grasses produce fine fuels in shrub interspaces, increasing the susceptibility of vegetation to wildfire. These grasses also quickly reinvade burned areas, often to the exclusion of native species, thus creating a positive feedback mechanism that enables them to convert shrubland ecosystems to annual grasslands on a landscape scale. During data collection for mapping annual grasses (primarily Bromus tectorum) with satellite imagery, groundcover of biological soil crusts was measured as well. These data do not show a mere negative correlation between cover of B. tectorum and biological soil crusts. Rather, they show a strong mutual exclusion between these vegetation components.
*POKORNY, LISA1, GISELA OLIVÁN2 and A. JONATHAN SHAW1 1Department of Biology, Duke University, 27708-0338, Durham, North Carolina, USA, 2Departamento de Biología Vegetal I, Universidad Complutense de Madrid, C/ José Antonio Novais 2, ES-28040 Madrid, Spain.
Contrasting phylogeographic patterns in two Southern Hemisphere Calyptrochaeta Desv. (Daltoniaceae, Bryophyta) species
The genus Calyptrochaeta Desv. is found almost exclusively in the Southern Hemisphere across tropical and temperate regions. Calyptrochaeta apiculata (Hook. f. & Wilson) Vitt is a widely distributed species that has been found in Chile, Argentina, the Falkland Islands, Marion Island, Australia, and New Zealand, plus a recent introduction in the Channel Islands (UK). Calyptrochaeta asplenioides (Brid.) Crosby is a widespread African endemic found in South Africa, Democratic Republic of Congo, Rwanda, Tanzania, Comoros, Madagascar, Reunion, and Mauritius. Even though C. apiculata has a broad distribution, it has few cpDNA haplotypes and the most common one is widely distributed across the range of the species. On the other hand, C. asplenioides has many haplotypes that show a remarkable geographic stratification that is also reflected in morphological differences among disjunct populations. We have tested alternative hypotheses about the dispersal and/or vicariance history of this second species. Diversification rates in C. asplenioides were estimated using Indian Ocean volcanic island ages as constraints.
*RIDDELL, JENNIFER1, THOMAS H. NASH III1 and PAMELA PADGETT2 1Arizona State University School of Life Sciences, PO Box 874601, Tempe AZ 85287, 2USDA F.S. Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, CA 92507
Investigating the effects of nitric acid on Ramalina menziesii Tayl.
Nitric acid and ozone, secondary products of photochemical reactions of nitrogen oxides (NOx) and volatile organic compounds, are important pollutants in arid regions with large outputs from petrol combustion. In the Los Angeles (LA) air basin, nitrogen dry deposition rates in forests downwind of the urban areas can reach 35-40 kg ha-1 year-1, roughly equivalent the amount of N used to fertilize agricultural fields. Surveys in the 1970’s and 1980’s showed that approximately 50% of the lichen species described in the LA air basin in the early 1900’s were extirpated, and many extant species had declined in abundance as well as showing signs OF physical damage. The researchers who described this phenomenon found that ozone concentration gradients overlaid the patterns of species extirpation. More recent research in the air basin has shown that nitrate deposition gradients run parallel to the ozone concentration gradient, and that nitrate and nitric acid can have significant effects on forest health. A 2004 resurvey in the San Bernardino Mts. showed a decline in abundance of formerly tolerant species. Our research examines the effects of nitric acid dry deposition on the lichen Ramalina menziesii Tayl. in an effort to understand the significant loss of species in southern California, and increase the usefulness of lichens as biomonitors of nitrogen pollutants. We transplanted healthy R. menziesii thalli from the UCSB Sedgwick Reserve, north of Santa Barbara, CA, into constantly stirred fumigation chambers in a climate-controlled greenhouse at UCR, Riverside, CA, into which we inserted varying levels of gaseous nitric acid. Ramalina menziesii thalli treated with nitric acid in month-long fumigations show a marked decline in chlorophyll content and carbon exchange capacity compared to thalli in control chambers. The leachate conductivity, nitrate and potassium concentrations increased with nitric acid fumigation levels and time, while sodium content decreased with time, not exposure. We conclude that R. menziesii has an unequivocally negative response to nitric acid gas concentrations common to ambient summer conditions in the LA air basin. Our next line of investigation will examine the threshold concentrations of damage to lichen thalli, as well as responses to factorial fumigations with O3 and HNO3.
SELVA, STEVEN University of Maine at Fort Kent, Division of Natural & Behavioral Sciences, 23 University Drive, Fort Kent, Maine 04743, USA
New and interesting calicioid lichens and fungi from eastern North America
Recent investigations of calicioid lichens and fungi in Great Smoky Mountains National Park in Tennessee and North Carolina, in old-growth northern white cedar stands in New Brunswick, Canada, and in regional lichen herbaria, have yielded a number of new and interesting records for North America. Calicioid species new to the North American biota include Chaenothecopsis amurensis, C. dolichocephala, and C. kalbii. Additional new records for eastern North America are Calicium adspersum, Chaenothecopsis subparoica, C. vainioana, and Phaeocalicium praecedens. In addition to these, range extensions for three other calicioid species (Chaenothecopsis brevipes, C. edbergii, and Phaeocalicium minutissimum)—described by the author as new North American records in earlier reports, are discussed.
*STANTON, DANIEL1 and JOHANA VILLAGRA2 1Princeton University, Department of Ecology and Evolutionary Biology, Princeton, New Jersey 08544, USA; 2Universidad Austral de Chile, Programa de Biología Ambiental, Valdivia, Chile.
Host Specificity in Atacama Desert epiphytes
One of the most striking aspects of many fog-ecosystems is the presence of a large biomass and diversity of epiphytic species. In the coastal deserts of Chile and Peru the majority of these epiphytes are lichens, notably many striking fruticose genera. Besides impressing naturalists since Darwin, these epiphytes potentially play a significant role in ecosystem processes in fog-oases, and may represent an important self-organizing vegetation structure. Epiphytes may be a significant source of water and nutrients for their host plants in water limited ecosystems. We compared the epiphytic communities of different host plants (cacti and shrubs) at several locations in northern Chile. Some host plants showed greater similarities between sites than with other taxa at the same site, suggesting host-specific associations. We also report the impact of epiphyte and tree cover on soil moisture and fog capture. These findings provide evidence towards a theory of epiphyte-host interactions in fog-oases as mutualisms.
*SWEAT, KEN G.1, THOMAS H. NASH III1, PANJAI PRAPAIPONG2 and PAUL T. GREMILLION3 1Arizona State University School of Life Sciences, PO Box 874601, Tempe AZ 85287; 2Arizona State University School of Earth and Space Exploration, PO Box 871404, Tempe, AZ 85287; 3Northern Arizona University Department of Civil and Environmental Engineering, PO Box 5621, Building 21/Room 132, Flagstaff, Arizona 86011
Comparison of Trace Metal Deposition in northern and central Arizona
Atmospheric deposition of trace elements to an epilithic lichen was assessed for an urban and rural area in Arizona, USA. The urban area consisted of 27 locations throughout Maricopa County corresponding to a previous study (Zschau et al., 2003); the rural area was 51 locations throughout the combined lands of the Grand Canyon National Park, Grand Canyon Parashant National Monument and areas of the Navajo Nation. Additional samples of Xanthoparmelia spp. were obtained from Arizona State University lichen herbarium material (1970-1973) sampled from the region to explore temporal trends, with an emphasis on decreases in Pb and Cu from the phase out of leaded gasoline and closing of copper smelters, and increases in Zn from agriculture. Lichens were cleaned, homogenized and then samples were split to be analyzed by both cold vapor technique for mercury (Hg) and wet digested in a high pressure microwave oven to analyze by high resolution ICP-MS for a suite of trace elemental concentrations [Aluminum (Al), Antimony (Sb), Arsenic (As), Barium (Ba), Bismuth (Bi), Cadmium (Cd), Caesium (Cs), Chromium (Cr), Cobalt (Co), Copper (Cu), Dysprosium (Dy), Erbium (Er), Europium (Eu), Gadolinium (Gd), Hafnium (Hf), Holmium (Ho), Iron (Fe), Lanthanum (La), Lead (Pb), Manganese (Mn), Molybdenum (Mo), Neodymium (Nd), Nickel (Ni), Niobium (Nb), Platinum (Pt), Praseodymium (Pr), Rhenium (Re), Rubidium (Rb), Samarium (Sm), Scandium (Sc), Selenium (Se), Silver (Ag), Strontium (Sr), Tantalum (Ta), Terbium (Tb), Thallium (Tl) Thorium (Th), Thulium (Tm), Tin (Sn), Titanium (Ti), Tungsten (W), Uranium (U), Vanadium (V), Ytterbium (Yb), Yttrium (Y), and Zinc (Zn)]. Replicate measurements of International Atomic Energy Agency 336 lichen standard reference material are in close agreement with the certified elemental compositions. Cluster analysis and principal components analysis are used to compare patterns of deposition from anthropogenic and geologic sources. Initial research suggests a significantly higher average mercury level in the urban lichens, although Hg is also emitted by power plants within 100 mile radius of the Grand Canyon area.
ZAMBRANO GARCÍA, ANGEL Dirección de Investigación y Postgrado, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas 157, México, D. F. 07730, MEXICO.
Lichens and air pollution in the valley of Mexico
A summary of experiences on using lichens as bioindicators of air pollution in the Valley of Mexico is presented. This valley is a high elevation (2,240 masl) and poorly ventilated region in central Mexico. It houses one of the most populated and air-polluted megalopolis in the world, Mexico City. Because this valley is almost entirely surrounded by forested mountain ranges, it provides a good opportunity to study effects from urban emissions on the natural vegetation. Since the forests located to the S-SW of Mexico City are closer to the urban area and lie most frequently in downwind position from it, they are the most affected by anthropogenic disturbance, including air pollution. Lichen biomonitoring of toxic airborne trace metals in the late 1980’s confirmed such an influence from the Mexico City environs for pollutants such as lead, an important component of gasoline in those years. Transplanting experiments in the 1990’s showed impairment of lichen photosynthesis and reduction of chlorophyll b near the city. In addition, a ca.50% potential reduction in species richness was detected for the epiphytic lichen communities of fir forests near the city. Herbarium evidence showed that some missing lichens in these forests were present and apparently in good condition in past decades. Evidence from controlled fumigation experiments with gaseous pollutants (SO2 and O3) showed decreased net photosynthesis for lichens known to be scarce (e.g., Parmotrema stuppeum, Sticta beauvoisii, Usnea ceratina) or absent (Teloschistes flavicans) in forests near Mexico City. Most recently, the potential role of secondary metabolites in protecting lichens from chronic oxidative air pollution is being studied by combining laboratory and field techniques, with promising results. Altogether these results confirm the usefulness of lichens as indicators of environmental threats to the local forest ecosystems. Since none of these forests is covered by the extensive air-pollution monitoring network of Mexico City, we may greatly benefit from using lichens as inexpensive bioindicators to alleviate the lack of information on the air quality exposure of those ecologically important areas. Thus, more work on the native lichens is needed, including taxonomic, ecological and ecophysiological studies to test effects from single and mixed air pollutants. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
*BARCENAS PEÑA, ALEJANDRINA1, MARÍA ANGELES HERRERA-CAMPOS1 and ROBERT LÜCKING2 1Universidad Nacional Autónoma de México, Departamento de Botánica, Instituto de Biología, Tercer circuito exterior, Cd. Universitaria, México, D. F. 04510. 2Department of Botany, The Field Museum, 1400 South Lake Shore Drive, Chicago, IL 60605-2496, USA.
Foliicolous lichen as indicators of the altitudinal zonation of the vegetation in the volcanos San Martin Tuxtla and Santa Marta, Los Tuxtlas, Veracruz, Mexico.
In the tropics, foliicolous lichens possess high potential as bioindicators of microclimate, seasonality, disturbances and altitudinal zonation. In Mexico, Sierra de los Tuxtlas, Veracruz is the northern extreme limit of the tropical rain forest in America. The most conspicuous elevations of this range are the volcanos San Martin Tuxtla (1580 m) and Santa Marta (1720 m), which were our study areas where the foliicolous lichens are used as indicators of the altitudinal variation of the vegetation. The species composition along four altitudinal gradients of 100 m was analyzed in the east and west sides of each volcano. A high diversity of species of foliicolous lichens and a low percentage of endemism were found at both sites. At each altitudinal level, a relationship was observed among three environmental variables: light, humidity and altitude, which in turn determine species diversity. At the same time, a preference of some of the lichen species for certain families of vascular phorophytes was observed. The highest diversity values of foliicolous lichens was found at the lowest altitudes in both volcanos and a significant change in the species composition was detected at 1400 m in the west and at 1500 m in the east side of San Martin Tuxtla; while in Santa Marta volcano such a difference occurred at 1500 m in both sides. The species composition variation of foliicolous lichens coincided with the change in the type of vegetation and in the microclimate. The different altitude at which such change occurs is explained by the "masses elevation effect" (Massenerhebungsefekkt). An inventory of 157 species of foliicolous lichens was obtained, 122 species growing on 23 families of vascular plants for San Martin Tuxtla volcano and 114 species on 32 families of plants for Santa Marta, having in common 76 species.
*CHATER, CASPAR1, JULIE GRAY2, ANDREW FLEMING1 and DAVID BEERLING1 1University of Sheffield, Department of Animal & Plant Sciences, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UNITED KINDOM, 2University of Sheffield, Department of Molecular Biology & Biotechnology, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UNITED KINDOM
Stomatal Function in Physcomitrella patens: a bryophyte controversy continues
Do bryophyte stomata play a role in carbon assimilation to the sporophyte? Are they directed by mechanisms similar to those in vascular plants? Whilst angiosperm stomata have been extensively studied, few plant biologists are even aware that mosses and hornworts possess them. For those that are, however, their function remains a contentious issue, with only one report of aperture control among many observations of immobility. Physcomitrella patens, with its dozen clearly visible localised stomata, is an ideal model organism to study stomatal development and physiology in the lower plants. Is there a straightforward answer to the bryophyte stoma question? Physcomitrella’s increasing use in molecular genetics provides an opportunity to test theories of vascular and non-vascular plant stomatal homology and may enhance our understanding of the evolution of sporophyte independence and dominance.
*HODKINSON, BRENDAN P.1 and MARTHA A. CASE2 1Duke University, Department of Biology, Box 90338, Durham, North Carolina 27708, USA; 2College of William and Mary, Department of Biology, P. O. Box 8795, Williamsburg, Virginia 23187, USA.
Lichen ecology in coastal ravines
The factors influencing lichen distribution can be quite complex and are often closely intertwined with one another. In this study, we characterize a community of coastal lichen species and investigate the ecological factors that may explain its unique features. In order to gain an overall understanding of the phytogeographic affinities of the Virginia Coastal Plain, we first conducted a floristic survey. This revealed much greater regional diversity than earlier publications would indicate, and showed that the area has significantly greater Appalachian affinities than previously suspected. The cyanolichens are one major group in which these differences in overall diversity and phytogeographic affinities are especially pronounced. We include a discussion of the role that the region’s unique ravine habitats may play in these unexpected results.
KOSOVICH-ANDERSON, YELENA Irkutsk State University, Department of Botany & Genetics, Sukhe-Bator Str., 5 Irkutsk-03, 664003, Russia.
On the bryophyte collection of the Irkutsk State University Herbarium (IRKU)
The scientific bryophyte collection of the Herbarium of the Department of Botany and Genetics, Irkutsk State University, Irkutsk, Russia, is being reported at this time. In 2006, the principal work of creating the collection was completed by Dr. Ye. Kosovich-Anderson, the IRKU bryophyte herbarium curator. Approximately one thousand and three hundred specimens in the newly developed collection are divided into two sections, which are “Bryophytes of South Siberia” and “World Bryophyte Collection”. The first includes about 1200 specimens of 114 species, which is approximately 20 % of the southern Siberian bryoflora. This section embraces bryophytes collected within the areas of Irkutsk oblast, the Buryat Republic and Chita oblast, all within Russian Federation. Of special scientific value, there are collections from protected areas of the Lake Baikal region, such as Pribaikalsky, Zabaikalsky and Tunkinsky National Parks. Most of these specimens have been collected by Ye. Kosovich-Anderson and her bryology students since the 1980’s up to 2006. Also, there are a large number of units of storage of common Siberian taiga mosses collected by Irkutsk State University biology students during their summer field practical courses on the southwestern Baikal coast in 1970-1990’s. Earlier collections of bryophytes dating from the early- to mid- 1900’s, placed either on herbarium sheets or in non-standard newspaper envelopes and including mostly common species, made by Department professors V.I. Smirnov, N.A. Epova, A. Sokolov, L.I. Nomokonov and others, who are either vascular plant or phytocoenosis researchers, are planned to be included in the Historical Herbarium section of IRKU. The preponderance of Baikal collections in IRKU’s bryophyte herbarium reflect the focus of the Department of Botany and Genetics research since 1919, the year of foundation of the department. The “World Bryophyte Collection” section includes specimens from the former USSR republics, Mongolia, Canada, USA, New Zealand, Tasmania, and South Wales, procured by Dr. Kosovich-Anderson as a result of herbarium exchanges between the botanical institutions of Russia and the USA in the 1990’s, and as a result of her bryophyte collecting in Wyoming, during her internship at the University of Wyoming Rocky Mountain Herbarium, Laramie, Wyoming (RM), in 2003-2004. The total number of bryophyte specimens at IRKU, both used in the educational process and as a scientific collection, is being estimated at around three thousand. Duplicates of some specimens are being kept at Komarov Botanical Institute, St. Petersburg (LE), and Pribaikalsky National Park Herbarium, Irkutsk.
*LEAVITT, STEVEN D. and LARRY L. ST.CLAIR Department of Integrative Biology and M.L. Bean Life Science Museum 290 MLBM, Brigham Young University, Provo, UT 84602, U.S.A.
Estimating population density and community structure for Xanthoparmelia spp. on Boulder Mountain, Aquarius Plateau, Utah, USA using two distance methods
Lichen community structure is correlated with various environmental and ecological factors. These patterns are often consistent and effectively accommodate the use of lichens as predictors of various kinds of ecological gradients. During this study we used two distance methods (point-quarter and individual-to-nearest neighbor) to estimate population density for several species of the foliose lichen genus Xanthoparmelia. In addition, a compound estimator (Diggle’s) was used to reduce sampling bias between the two distance methods. Relative species abundance was compared between meadow areas, individual rock outcrops, cardinal directions, and general substrate characteristics. The data showed that Xanthoparmelia species sampled during this study varied widely in density and community structure across a relatively homogeneous landscape. Microhabitat, meadow-wide and plateau-wide environmental conditions combined to influence Xanthoparmelia community structure. Our data documents the inherent variability found among lichen communities as well as the importance of effective sampling in order to accurately document community structure. This study also suggests that Diggle’s population density estimator, combining data obtained using both the point-quarter and individual-to-nearest neighbor distance methods, may be the most effective approach to accurately estimate population density and community structure of terricolous and saxicolous lichens.
*MOSHMAN, REBECCA and ROBERT EGAN Department of Biology, University of Nebraska at Omaha, Omaha, NE 68182, USA.
Studies on the distribution of the Parmotrema perforatum group in southeastern Oklahoma, eastern and central Texas, western Louisiana, and western Arkansas
Mass collections were made of the Parmotrema perforatum group at numerous localities in Oklahoma, Texas, Louisiana and western Arkansas. When TLC analyses revealed up to 6 species present at a single locality, we decided to quantify the joint occurrence of these taxa. We cleaned each thallus of substrate and calculated for biomass of each species at each locality, and the data were analyzed for each site by taxon, reproductive mode, chemical profile, and local vegetation type. Individual species showed some geographical pattern trends. Parmotrema subrigidum occurs most densely in the pinelands area of eastern Texas. In southern Texas, only P. subrigidum is present, while P. preperforatum is most abundant in the post oak savanna in central Texas and does not occur in the hill country or north into Oklahoma and Arkansas. Parmotrema perforatum is most abundant in the northern areas. In the hill country, post oak savanna, and pinelands, P. perforatum occurs in percentages from 15%-27%. Parmotrema hypotropum is widespread: most abundant in the hill country (66-100%) and also accounts for a substantial portion of biomass in the post oak savanna. Parmotrema louisianae was found only at three localities in the pinelands, most abundantly in western Louisiana. Parmotrema hypoleucinum occurs in small percentages in the hill country and post oak savanna. Its highest abundance was in the pinelands of Caddo Parish, Louisiana(25%). Unexpectedly, Parmotrema hypoleucinum was not found in the Texas coastal counties but increaseed in abundance to the north. In the analyses by vegetation types, the Texas hill country is dominated by P. hypotropum while the post oak savanna of east central Texas is dominated by P. subrigidum and P. preperforatum. The east Texas-western Louisiana pinelands are again dominated by P. subrigidum with P. louisianae more common in Louisiana. In the “Ozark” type forests to the north, P. perforatum dominates. Chemically, only the alectoronic acid-containing species demonstrated a geographical preference, becoming 100% dominant (as P. subrigidum) in coastal areas. We could find no distinct pattern to the distribution of primary (apotheciate) or secondary (sorediate) taxa. East Texas and western Louisiana are biodiversity “hot spots” for the Parmotrema perforatum group. All six taxa occur together at one locality in western Louisiana. It is vital that individual thalli in collections from this region be carefully tested to ensure accurate identification.
*PAPONG, KHWANRUAN1, ROBERT LÜCKING2, ACHRA THAMMATHAWORN1 and KANSRI BOONBRAGOB3 1Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen Province, Thailand, 42001; 2Department of Botany, The Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, IL 60605-2496, USA; 3Department of Biology, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand, 10240.
Historic biogeography and phylogeny of the lichen genus Chroodiscus (Ascomycota: Thelotremataceae), with the description of four new taxa from Thailand
Based on a phenotype-based phylogeny, we studied the historic biogeography of Chroodiscus (Ascomycota: Ostropales: Thelotremataceae), a pantropical foliicolous lichen genus comprising 14 taxa, including four new taxa from SE Asia described herein: C. homchantarae, C. khaolungensis, C. khaosokensis, and C. defectus. Five clades (grades) are distinguished: the paraphyletic C. parvisporus grade (apothecia grey, thallus smooth, Trentepohlia, stictic acid), the monophyletic C. mirificus clade (apothecia grey, thallus smooth, Trentepohlia, stictic acid, disc-shaped isidia), the monospecific C. australiensis
clade (apothecia scarlet-red, thallus smooth, Trentepohlia, anthraquinone), the monophyletic C. verrucosus clade (apothecia grey, thallus verrucose, Phycopeltis, stictic acid), and the monophyletic C. coccineus clade (apothecia scarlet-red, thallus verrucose, Phycopeltis, anthraquinone). The C. parvisporus grade is characterized by plesiomorphic characters, while the C. coccineus clade is the most derived branch. The latter is neotropical, whereas the C. mirificus clade is SE Asian; all other clades (grades) are pantropical. Dispersal-vicariance analysis (DIVA), together with assessment of plesiomorphy / apomorphy levels, suggests origin of Chroodiscus in SE Asia, from where the ancestor of the C. parvisporus grade expanded towards S America and Africa. The origin of the clade including C. australiensis, C. verrucosus, and C. coccineus, is indicated to be S America, with the first two clades subsequently spreading to Africa and then back to SE Asia. Comparison with tropical rain forest paleogeography suggests that the genus probably evolved in the mid to late Cretaceous, during the expansion of angiosperm-dominated tropical rain forests. The details of subsequent expansion of primitive species of the genus to cover all main tropical regions (C. parvisporus, C. australiensis) remains unresolved, but the close relationship of the chiefly American-African C. coccineus and C. verrucosus clades correlates with the late separation of the two continents during the Paleocene and Eocene. The common ancestor of both clades appears to have been C. verrucosus-like, and the C. coccineus clade probably evolved after separation of the two continents.
*RICE, S.K., S. GLOVER and L. ACLANDER Department of Biological Sciences, Union College, Schenectady, NY 12308.
Vertical distribution of light, chlorophyll, nitrogen and photosynthesis in Sphagnum canopies.
Light, photosynthetic pigments and N distribute vertically within bryophyte canopies. Consequently, rates of photosynthesis should vary at different depths and influence whole plant carbon gain. Using a comparative approach with common-garden plants, we explored whether variation in whole-canopy rates of photosynthesis observed among species could be caused by differences in the vertical distribution of light and photosynthetic complexes as evidenced by chlorophyll and N concentrations. Three Sphagnum species (S. fallax, S. magellanicum and S. fuscum) that differ in their morphology were collected and cultured in a greenhouse for 90 days. Photosynthetic function within canopies was assessed using the chlorophyll fluorescence Quantum Yield parameter (Fv/Fm) at 1 cm vertical intervals. Also, biomass, chlorophyll and N were measured in 1-2 cm increments and light attenuation was evaluated using a fiber optic
probe at 0.25 cm intervals. Whole-canopy net photosynthesis was assessed as net CO2 exchange across a range of light intensities (30-750 PPFD) and compared with canopy attributes. Maximum rates of photosynthesis expressed relative to biomass (Amass) showed less variation than when expressed on N (PNUE) or chlorophyll (Achl) bases. S. fallax, the species with the highest PNUE and Achl, had the lowest N and chlorophyll concentrations, but allowed deeper light penetration within the canopy. This species also showed the strongest attenuation of Quantum Yield within the canopy, suggesting that enhanced light transmission in the canopy increases whole canopy photosynthesis, even when photosynthetic function as expressed through Quantum Yield declines.
SHUSTOV, MIKHAIL V. Institute of Ecology of the Volga river basin of Russian Academy of Sc., Komzin st., 10, Togliatty, 445003, Russia.
The lichens in the Red Data Book of the Samarskaya region (European Russia)
At the present time, the Samarskaya region Red Data Book contains 8 lichen species (tab. 1), and 11 lichen species are recommended to be included in this Book (tab. 2).
Table 1. The lichens included in the Red Data Book of the Samarskaya region.
Table 2. The lichens recommended to be included in the Red Data Book of the Samarskaya region.
SHUSTOV, MIKHAIL V. Institute of Ecology of the Volga river basin of Russian Academy of Sc., Komzin st., 10, Togliatty, 445003, Russia.
The lichens in the Red Data Book of the Ulyanovskaya region (European Russia)
At the present time, the Ulyanovskaya region Red Data Book contains 32 lichen species (tab. 1).
Table 1. The lichens included in the Red Data Book of the Ulyanovskaya region.
*SLACK, NANCY1, NAT CLEAVITT2 and SUE WILLIAMS3 1Department of Biology, The Sage Colleges, Troy NY,12180, USA: 2Department of Natural Resources, Cornell University, Ithaca, NY 14850, USA; 3 7 Middletown Hill Rd., Rowe, MA 01367, USA
Rarity in bryophytes; New York studies
Over 450 species of mosses have been collected in New York State; many are rare. The state contains diverse habitats including bogs, rich fens, alvar, and alpine summits over 1700 m. Mosses previously listed as rare or historical (SH) were examined in six herbaria. We carried out a quantitative study, concentrating on cliff sites; calcareous cliffs in particular contain microhabitats of rare moss species. Thirty-two sites, 19 cliffs and 13 others, yielded 1000 vouchers of 170 species including 36 collections of rare New York mosses, as well a Fabronia ciliaris and Tortula pagorum, southern species new to New York. Rich fens, alvar and other unusual habitats also yielded rare species. Of 53 previously ranked as historical only 24 remain in that category. Several introduced species new to New York are currently rare. Other reasons for rarity of New York mosses include very specific microhabitats, habitat destruction, and edge of range. Under collection of small, inconspicuous mosses such as ephemerals and Seligeria species had resulted in apparent rarity. We produced a new checklist of rare mosses of New York State, which can be updated with future discoveries. Research supported by the Biodiversity Research Institute, NY State Museum.
TRATEBAS, ALICE M.1,*PETER RIRIE2, and LARRY L. ST. CLAIR2 1New Castle Field Office of The Bureau of Land Reclamation and 2M.L Bean Life Science Museum 290 MLBM, Brigham Young University, Provo, UT 84602, U.S.A.
Lichen encroachment on rock art panels in western Wyoming
Research concerning lichen encroachment on ancient rock art panels in western Wyoming was initiated in the fall of 2000. Across all panels a total of 66 species in 37 genera have been identified. Species diversity varies between panels, but the following taxa were commonly reported from most panels: Peltula euploca, Acarospora spp., Caloplaca fraudans, Candelariella spp., Sarcogyne spp., Polysporina simplex, Aspicilia desertorum and Physciella chloantha. Lichen development on panels is consistently associated with eroded surfaces of petroglyphs. Species distribution patterns on individual panels are clearly correlated with microclimatic factors including: shading by adjacent woody plants and water flow patterns over panel surfaces during precipitation events. Lichen development on panels with intact desert varnish was severely limited. In order to effectively monitor patterns of encroachment and biodeterioration we have established permanent photographic plots at several panels. The potential use of lichen biocides and/or the physical removal of lichen thalli has been discussed; however, input from the local Native American community resulted in the decision to avoid the use of this type of aggressive control measure. In order to evaluate potential air pollution-related impact on the panels, we analyzed samples of three air pollution sensitive lichen species (Xanthoparmelia cumberlandia, Rhizoplaca melanophthalma, and Usnea subfloridana). More than 20 potential air pollutant elements were determined using PIXE techniques. Elemental analysis data was collected to determine if air quality may be a factor in the deterioration of some panels. Sulfur concentrations (.194-.23%) in samples of Usnea subfloridana from two locations in the canyon were elevated. Concentrations of two heavy metals (As and Ni) were also slightly elevated; suggesting at least some limited potential for air pollution-related impact on panels.
*WIDHELM, TODD, ROBERT EGAN and TATYANYA LIVSHULTZ University of Nebraska at Omaha, Department of Biology, Omaha, Nebraska 68182-0040, USA.
Phylogenetic Relationships in the Parmotrema perforatum group in North America based on the glyceraldehyde-3-phosphate (GDP) gene
The Parmotrema perforatum group consists of six lichen species subdivided into three chemically distinct species pairs, each with an asexual species and a sexual species. This study tests the validity of this evolutionary interpretation of the P. perforatum group and the status of the norstictic acid-containing chemotype of P. subrigidum using DNA sequence data from the glyceraldehyde-3-phosphate (GPD) gene. Fresh specimens were collected during the summer of 2006 in Oklahoma, Texas, Louisiana, and Arkansas, including the type localities for P. preperforatum and P. louisianae. In the laboratory, each individual thallus from each locality was chemically screened by standard TLC techniques before DNA was extracted. Sequences were then generated to be used in parsimony analysis. The distribution of alleles will provide data that may indicate gene flow between species in the group. If alleles are fixed within species, the current classification will be supported. If the alleles are distributed among species then this would be evidence that suggests that gene flow is occurring between species. So far, conspecific sequences from currently recognized taxa have been observed as both monophyletic (P. subrigidum) and paraphyletic (P. perforatum). However, two of the three species pairs are not monophyletic. P. hypotropum is sister to P. preperforatum and P. hypoleucinum is sister to P. subrigidum. In these cases, the sequence from an asexually reproducing individual of one chemotype, has been found sister to the sequence from a sexually reproducing member from another chemotype. The single sequence of P. louisianae currently nests within the P. subrigidum grouping, the alectoronic acid-containing species pair. Analyses of numerous additional sequences, currently underway, should further resolve these relationships.
*ZAMBRANO GARCÍA, ANGEL1, NORMA A. VALENCIA ISLAS1,2 and JOSÉ ROJAS2 1Dirección de Investigación y Posgrado, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas 152, México, DF, 07730, MÉXICO; 2Universidad Nacional de Colombia, Bogotá, COLOMBIA.
Lichen secondary metabolites as potential biomarkers for chronic oxidative air pollution
Lichen secondary metabolites (LSM) protect lichens from a variety of environmental stress factors, but little is known on their potential to protect from air pollution. We explored six phenolic LSM as biomarkers for chronic oxidative air pollution in forests near Mexico City. The antioxidant activity and antiradical power of boninic (BO), 2-O-methylsekikaic (MA) and usnic (US) acids, isolated from a lichen tolerant to the Mexico City environs (Ramalina asahinae W. Culb. and C. Culb.), and salazinic acid (SA), atranorin (AT) and chloroatranorin (CA), from the sensitive Parmotrema stuppeum (Taylor) Hale, were determined in vitro with ozone and the free radical DPPH●, respectively. In addition, the field concentrations of these phenolics and the potential antioxidant capacity (PAC) they provide to the lichens were compared among forested sites exposed to urban emissions from Mexico City and a similar, relatively clean site. The six LSM had antioxidant activity and antiradical power according to these trends: CA >> AT > US > SA ≥ BO ≥ MA, for O3; and CA > AT > US > MA > SA = BO, for DPPH●. The three most reactive phenolics are cortical compounds, meaning that they are located in the lichen portion most exposed to the surrounding environment. In contrast, the less reactive SA, BO and MA are medullary. Such reactivity patterns in the lichen thalli indicate that some phenolics provide antioxidative protection at the air-lichen interface. In the field comparisons, the total quantified phenolics (TQP) were significantly higher near Mexico City for both lichens, except for the tolerant R. asahinae at one site. Nevertheless, only the latter species had significantly increased PAC values at all sites near the city. This result is explained by species-dependent changes in individual phenolics. At the polluted sites, R. asahinae had consistently higher contents of its most reactive phenolic, US, with values approximately twice that of the control site. In contrast, P. stuppeum only increased its less reactive SA (26-35%), but this was counteracted by CA degradation. Thus, the substantial increase in US at the polluted sites appeared associated with the current ecological success of R. asahinae near the city. On the other hand, the inability of P. stuppeum to overcome degradation of its most reactive phenolic (CA) at the same sites seems to partially explain the declining status of this lichen. These results provide evidence for a protective mechanism in lichens against air pollution based on LSM.
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