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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The role of bryophytes and lichens as community members in the upland forests of southern Wisconsin

Hale, Mason E. January 1953 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1953. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [98-101]).
52

Das ozeanische Element der Strauch- und Laubflechten-flora von Skandinavien

Degelius, Gunnar, January 1935 (has links)
Inaug. Diss. -- Uppsala. / "Zitierte Literatur": p. [371]-401.
53

Diversity and growth of epiphytic macrolichens in northwestern Patagonian Nothofagus forests /

Caldiz, Mayra S. January 2005 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2005. / Thesis documentation sheet inserted. Appendix reproduces four papers and manuscripts, three co-authored with others. Includes bibliographical references. Also partially available electronically via World Wide Web in PDF format; online version lacks appendix.
54

The response of lichens to changes in isotopic composition and concentration of atmospheric sulphur : a reciprocal transplant experiment /

Cousineau, Mélanie Lyne, January 2003 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Restricted until May 2005. Includes bibliographical references.
55

The lichens of the coastal douglas-fir dry subzone of British Columbia

Noble, Willa Jane January 1982 (has links)
Lichenological studies in western North America have lagged behind those of eastern North America and Europe. Several manuals, now mainly outdated, are available for the western United States; no descriptions or keys have ever been compiled for the British Columbia lichen flora. This flora of the Coastal Douglas-fir Dry Subzone in British Columbia, Canada, partially fills this void. The Coastal Douglas-fir Dry Subzone is a small area in the southwestern portion of the province composed of a narrow strip on the eastern side of Vancouver Island and the adjacent Gulf Islands in the Strait of Georgia. It is a unique area in the province with a Mediterranean-type climate. It also has a large and increasing human population. Most of the subzone has been logged once although second growth forests now cover much of the region not utilized by the human population. The lichen flora is based primarily on 5,500 specimens collected for this study. In addition, someminor herbarium collections, including later collections of John Macoun, are also included. A total of 448 species in 114 genera, including 26 species from adjacent zones are treated. Keys and concise descriptions are provided plus information on substratum preferences, abundance within the subzone, and taxonomic problems. Spore diagrams are supplied for many of the crustose genera, especially those with septate or muriform spores. One species new to science already has been published, Gyalideopsis aim'col a Noble & Vezda, and several others are to be described in future publications. One new combination has already been made, Catillaria columbiana (Merr.) Noble, and two others, Lecanora ochrococca (Nyl.) Noble and Arthothelium macounii (Merr.) Noble, will be published in a forthcoming checklist of the province. Lecanora phaeobaea Tuck, has proved to be synonymous with Lecanora ochroccoca, and Solenospora hassei (Zahlbr.) Zahlbr. with Lecania dudleyi Herre. Ninety-six species new to British Columbia were encountered, primarily among the microlichens. Ten genera were added to the provincial checklist. A first assessment of many taxonomic problems was made and others noted. Type specimens of many poorly known California species were examined for confirmation of identification- of the local collections. Some difficult genera require monographic treatment before the local flora can be treated any more than tentatively. Local distributions within the subzone are discussed. Eight patterns are distinguished reflecting frequency, climate constraints, substratum restrictions, and human influences. Oceanic distributions make up several distinctive patterns including marine oceanic, strictly oceanic (non-marine) and hyperoceanic. An analysis of the world distributions of the species composing the local flora showed that the majority are very widespread with an essentially continuous range. Twelve different elements are recognized. Important elements include the circumboreal element (31%), the western North American endemic element (18%), the circumtemperate element (12%), the western North America-Europe disjunct element (11%), and the western North America-eastern North America-Europe disjunct element (8%). Eastern Asia, despite its relative proximity, has only minor affinities with the local flora. This study is a preliminary flora of the lichens of the Coastal Douglas-fir Dry Subzone. It provides a manual to encourage others to look at these poorly known cryptogams; it also acts as the foundation for future work. / Science, Faculty of / Botany, Department of / Graduate
56

Distribution and abundance of arboreal lichens and their use as forage by blacktailed deer

Stevenson, Susan K. January 1978 (has links)
Biomass of arboreal lichens used as winter food by blacktailed deer was studied. Three methods were used to assess abundance of Alectoria sarraentosa and Bryoria spp. Lichen biomass was measured by sampling the lichens from felled trees. A system of visual estimates of lichen abundance was developed and related to biomass estimates obtained by sampling. A predictive equation {Y = 158.03 {A x CL), where Y is lichen biomass, A is an estimate of lichen cover on a portion of the tree crown, and CL is crown length; n = 40; Sy,x = 376,89; r2 = 0,75) was used to extrapolate lichen biomass values from sampled trees to unsampled trees. The value of large-scale colour infrared air photography as a tool for inventorying lichen abundance was assessed, using densitometry and photo interpretation. Some positive relationships with lichen abundance were found using each method, but neither densitometry nor photo interpretation was demonstrated to have strong potential for use in inventorying abundance of arboreal lichens. Biomass of Alectoria (sensu lato) on the 14 plots studied ranged from 21 to 1528 kg/ha. Physical and vegetative characteristics of the plots were measured and related to lichen abundance. Taken together, slope, aspect, and elevation accounted for 82 percent of the variation in lichen abundance. Forest productivity was negatively related to lichen abundance, lithin the range of sites studied, Alectoria (s.1.) was most abundant on moderate to steep south-facing slopes, at elevations above 500 m, where tree growth was poor. To assess availability of lichens and their utilization by deer, litterfall was measured inside and outside exclosures on three sites where levels of deer use in winter were known. The relationships between litter deposition rates and weather were examined. Quantities of Alectoria (s.1.) litter were 69.9 kg/ha/180 days in a severe winter range area, 151.2 kg/ha/180 days in a mild winter range area, and 31.9 kg/ha/180 days in a poor winter range area. On all three sites, significantly more (p ≤ 0.05) Alectoria litter was present inside than outside exclosures; guantities of non-lichen litter did not differ significantly. Utilization of Alectoria was 37, 53, and 52 percent of available guantities on the three sites, respectively. The relationship between lichen abundance and selection of winter habitat by blacktailed deer was assessed, based on pellet group counts, track counts, and the data of other investigators. Areas selected by deer as winter range tended to be moderate or high in lichen abundance. / Forestry, Faculty of / Graduate
57

Environmental factors affecting net CO2 assimilation in Cladonia alpestris (L.) Rabh. in the subarctic

Carstairs, Anne Graham. January 1976 (has links)
No description available.
58

Field and laboratory studies on the ecology and physiology of selected algae, mosses and lichens from Antarctica /

Schofield, Edmund Acton January 1972 (has links)
No description available.
59

The accumulation of chromium by two species of the lichen genus Parmelia and subsequent effects /

Schutte, Julia Ann January 1976 (has links)
No description available.
60

AN ECOLOGICAL ASSESSMENT OF AN ENDANGERED LICHEN FROM CENTRAL CALIFORNIA: SULCARIA ISIDIIFERA, THE SPLITTING YARN LICHEN

Balderas, Elijah C 01 December 2023 (has links) (PDF)
Lichens are an underrepresented group of organisms when it comes to both research and conservation efforts. At the same time, lichens face increasing threats from anthropogenic sources including wildfires, climate change and urbanization. With this thesis, I seek to ascertain and publish ecological data on a critically endangered lichen to inform future conservation designations and efforts to preserve and protect the species in perpetuity. In Chapter 1, I provide an ecological overview of the known range of Sulcaria isidiifera and assess the status of Sulcaria isidiifera via a population count. Sulcaria isidiifera occurs in maritime chaparral habitat in the Los Osos-Baywood Park-Morro Bay area of San Luis Obispo County, California. Although apparently similar maritime chaparral is known from a much larger range along the coast of California, S. isidiifera has never been found outside of this extremely local population area. Population data collected during the study determined there are an estimated 3,588-7,772 mature individuals of S. isidiifera range-wide. Chapter 1 also characterizes the vascular plant vegetation community, microclimate parameters, and lichen community assemblage in which S. isidiifera occurs. The elegant fringe lichen (Leucodermia leucomelos) was found to be a strong indicator for the presence of S. isidiifera. Chamise (Adenostoma fasciculatum), buck brush (Ceanothus cuneatus), and Morro manzanita (Arctostaphylos morroensis) were the most common shrub species on which S. isidiifera was found. In Chapter 2, conservation translocation was tested as a mitigation strategy for the previously observed population decline of S. isidiifera. Whole thalli were translocated while attached to their original substrate to adjacent shrubs in suitable habitat that was not occupied by S. isidiifera. The vitality of translocated thalli was tested using chlorophyll fluorescence techniques. After 13.5 months, I report 100 percent survival of translocated thalli with no significant negative impacts to thallus health. The S. isidiifera transplants will continue to be monitored indefinitely. Guidance on future conservation translocations for S. isidiifera is provided and these methods will continue to be updated as further observations and results are gathered.

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