John W. Sheard

Ecological Land Classification: A Survey Approach

A landscape approach to ecological land mapping, as illustrated in this article, proceeds by pattern recognition based on ecological theory. The unit areas delineated are hypotheses that arise from a knowledge of what is ecologically important in the land. Units formed by the mapper are likely to be inefficient or irrelevant for ecological purposes unless he possesses a sound rationale as to the interactions and controlling influences of the structural components of ecosystems. Here is the central problem with what have been called “objective” multivariate approaches to mapping based on grid units and the sometimes arbitrary attributes thereof; they tend to conceal the importance of ecological theory and the necessity for theory-based supervision of pattern recognition. Multivariate techniques are best used iteratively to verify and refine map units initially recognized and delineated by theoretical considerations. These ideas are illustrated by an example of a reconnaissance survey in the Northwest Territories of Canada.

Identification and description of forested vegetation communities available to woodland caribou: relating wildlife habitat to forest cover data

Abstract Multivariate analyses were applied to forest canopy and understory data collected in 70 forest stands in the Mid-Boreal Upland Ecoregion in Saskatchewan. Random sampling of various types of forest focused on vegetation strata shown elsewhere to be of importance to woodland caribou (Rangifer tarandus caribou Gmelin). Cluster analyses revealed seven community types based on summer vegetation, and six community types when considering vegetation present during winter. Ordination by nonmetric multidimensional scaling suggested that two of the seven summer communities be combined, and that six community types be recognized in each season. Stands dominated by Populus tremuloides Michx. were all placed in one community type as were those dominated by Picea glauca (Moench) Voss. Young stands of Pinus banksiana Lamb. were placed in one community type, while the division of older stands was related to degree of canopy closure. The primary division among Picea mariana (Mill.) B.S.P. dominated stands was also based on the degree of canopy closure. Canonical correspondence analysis revealed strong relationships between the vegetation communities and data on canopy characteristics contained in the provincial forest inventory. In general, the techniques we employ provide a framework for objectively deriving vegetation communities relevant to wildlife species, and measuring their correspondence with readily available forest cover data. Specifically, we describe community types available to woodland caribou in our study area and their relationship to the provincial forest inventory.

A Synopsis of the Species of Amandinea (Lichenized Ascomycetes, Physciaceae) as Presently Known in North America

Ascomata, ascus, spore anatomy, spore wall ornamentation, and conidiophore type are discussed with respect to the limits of the genus Amandinea Scheid. & Mayrh. Four new species combinations are made and eight taxa placed in synonymy. Amandinea dakotensis (H. Magn.) P. May & Sheard comb. nov. and A. milliaria (Tuck.) P. May & Sheard comb. nov. are transferred from the genus Rinodina (Ach.) Gray. Amandinea leucomela (Imshaug) P. May & Sheard comb. nov. and A. polyspora (Willey) E. Lay & P. May comb. nov. are transferred from Buellia De Not. The genus Amandinea Scheid. & Mayrh. includes crustose and squamulose members of the Physciaceae with filiform and curved (arcuate, Lamb 1968) conidia, 15-30 jim long (Matzer et al. 1994; Scheidegger 1993). Two other genera in the family, Australiaena Matzer, Mayrh. & Elix (Matzer et al. 1997) and Hyperphyscia Mill. Arg. (Hafellner et al. 1979), also possess this type of conidium. Australiaena is distinguished primarily by its radiate-plicate thallus margin and chemistry, and Hyperphyscia by its foliose thallus. Esslinger and Egan (1995) listed two species of Amandinea for North America, A. coniops (Wahlenb.) Scheid. & H. Mayrh., the type species for the genus, and A. punctata (Hoffm.) Coppins & Scheid. Both species were originally transferred from Buellia and are characterized by biatorine or lecideine apothecia with darkly pigmented hypothecia. Amandinea coniops is described as possessing physconia-type spores and A. punctata, buellia-type spores (Scheidegger 1993). A third species, A. lecideina (H. Mayrh. & Poelt) Scheid. & H. Mayrh., first desribed as a Rinodina (Mayrh. & Poelt 1979), has lecideine apothecia and physconia-type spores. Matzer et al. (1994) transferred Rinodina petermannii (Hue) Darbishire to Amandinea, another species with buellia-type spores, but which typically possesses lecanorine apothecia with hyaline hypothecia. As circumscribed by the authors cited above, apothecial type in Amandinea varies from lecideine, through biatorine to lecanorine, and the spores may or may not possess lateral wall thickenings at the septum. Chemistry is also not uniform for all species since A. petermannii (Hue) Matzer, H. Mayrh. & Scheid. may include norstictic acid in contrast to the other species which lack secondary products. Rambold et al. (1994) surveyed ascal types within the Physciaceae and found that Amandinea and Buellia species possess the bacidia-type (including lecidella-type, Rambold 1989) ascal structure, whereas Rinodina species exhibit the lecanora-type structure. However, there are exceptions in both Rinodina and Buellia (Giralt & Matzer 1994; Rambold et al. 1994). Rambold et al. regard ascus type as being the primary character of the genus, whereas Giralt and Matzer (1994) consider spore type as the primary character. Variation of ascus structure within species has not been reported for Amandi-

Buellia Japonica (Physciaceae), a New Lichen Record for North America

Abstract The lichen Buellia japonica is reported for the first time from North America based on collections from Gorges State Park, North Carolina. A description of the species is provided and its generic placement is discussed.

New species of Rinodina (Physciaceae, Lichenized Ascomycetes) from Western North America

Abstract Fourteen new species are described from western North America– Rinodina aurantiaca, R. badiexcipula, R. boulderensis, R. californiensis, R. endospora, R. grandilocularis, R. innata, R. juniperina, R. lignicola, R. lobulata, R. macrospora, R. pacifica, R. perreagens, and R. verruciformis. Characters on which they are based are discussed in detail and a new spore type for Rinodina is introduced. The new species are compared to others, with which they might be confused and a key provided. Rinodina dolichospora is recorded for the first time from North America.

Three new species of Rinodina (Physciaceae) and a new record from North America

Abstract Rinodina campestris, R. megistospora and R. terricola are described as new to science. Rinodina boleana is recorded for the first time from North America and is compared in detail to R. pyrina and R. imshaugii and all are shown to possess Dirinaria–type spores.

Rinodina intermedia (Physciaceae, Lichenized Ascomycetes): A Well-characterized Species with Submuriform Ascospores

Abstract Rinodina intermedia Bagl. is distinguished from R. conradii Körb. on the basis of its Type-A spore development, submuriform spores, and the presence of a new lichen substance, deoxylichesterinic acid. Both species are primarily ground dwelling and are mostly allopatric in their North American and world distributions, R. intermedia being warm temperate whereas R. conradii is cold temperate. Both species occur in Colorado, the Andes, and Himalaya Mountains, R. conradii being found at higher elevations. Rinodina diplinthia (Nyl.) Zahlbr., R. darrovii E. D. Rudolph, and R. conradii var. megaspora D. D. Awasthi & M. R. Agarwal are placed into synonomy for the first time. Lectotypes for R. lusitanica Arnold and R. sabulosa Tuck. are selected.

Two New Species of the Lichenized Ascomycete Genus Dimelaena Norm.

Two new species of Dimelaena are described--D. weberi Sheard from North America and D. australiensis Mayrhofer and Sheard from Australia. Their phytogeographic relationships with other species in the genus are discussed. The taxonomic relationships of the genus with Buellia, Rinodina and Rinodinella are also considered on the basis of new and other recent evidence. During the course of our studies on the Physci- aceae, two new species of Dimelaena have come to our attention. The genus Dimelaena was historically included in Rinodina (Zahlbruckner 1926), but, fol- lowing Hale and Culberson (1970), Sheard (1974) treated it as a separate genus, redefining its limits to include only those species with an unthickened spore wall and a radiate-plicate thallus margin. The presence in a number of species of cryptolecanorine apothecia and a dark hypothecium suggests a closer relationship with Buellia than with Rinodina. Mayrhofer (1982) describes three types of unthick- ened spore; the Rinodinella-, Beltraminia- (in the genus Dimelaena) and the Buellia-types, the last lacking a torus. One of us (J.W.S.) would prefer to treat the latter two spore types as one, the Buellia- type, at least for the present. Buellia-type spores, in either sense, do not occur in Rinodina and the re- ports of such by Mayrhofer and Poelt (1979) are erroneous. A number of species should be trans- ferred from Rinodina to Buellia on this account. Rinodinella-type spores are distinct in their light pigmentation, subcylindrical form and very thin walls. The genus Rinodinella is, therefore, well sep- arated from Dimelaena by both spore type and lack of a radiate-plicate thallus margin.

Rinodina stictica, a New Corticolous, Sorediate Lichen Species from the Pacific Northwest of North America

Rinodina stictica Sheard & Tonsberg is described as new from Washington State, U.S.A., where it is epiphytic on deciduous trees in coastal lowlands. The species is soraliate and possesses features unusualfor Rinodina such as stictic acid, and callispora-like locules in developing, immature spores, which belong to the pachysporaria-type at maturity.

Distribution of vegetation along environmental gradients on Sable Island, Nova Scotia.

Abstract: Coastal sand dune ecosystems are known to be structured by disturbance along coast-to-inland gradients, but little is known about how such patterns might change on exposed islands where environmental gradients vector in multiple directions. We investigated responses in plant assemblages on Sable Island, a long (49 km) and narrow (1.25 km at the centre) mostly vegetated sand bar located 160 km off the east coast of Nova Scotia, Canada. We sampled vegetation composition across the island using a stratified random design to capture a range of environmental predictors potentially associated with substrate conditions and disturbance from coastal processes, as well as grazing by the islands feral horses. We identified 3 different vegetation assemblages using hierarchical cluster analysis and non-metric multidimensional scaling that were associated with predictor variables. Distance from shore (both north and south shore) and slope angle were strongly related to both vegetation distribution and community composition. Areas farther from shore (subject to less wind and wave disturbance) contained greater amounts of shrub and heath vegetation. However, all parts of the island contained non-vegetated areas or stress-tolerant plant communities. Patterns of vegetation succession inferred for Sable Island were not linear and are better described as responses to repeated environmental disturbance rather than to a gradual process of soil development and competitive displacement. In addition to highlighting the multi-directional environmental influences on community composition of island systems, our results establish baseline spatial information on vegetation communities necessary for the ecological monitoring of Sable Island as a new National Park Reserve.