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Lichens Of Six Vernal Pools In Acadia National Park, Maine, Usa, Jason Barton, Brett Ciccotelli, Jillian E. Gall, Fred C. Olday, Bruce Connery, Tanner B. Harris, Alan M. Fryday, Nishanta Rajakaruna Mar 2014

Lichens Of Six Vernal Pools In Acadia National Park, Maine, Usa, Jason Barton, Brett Ciccotelli, Jillian E. Gall, Fred C. Olday, Bruce Connery, Tanner B. Harris, Alan M. Fryday, Nishanta Rajakaruna

Nishanta Rajakaruna

Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia ...


Additional Lichen Records And Minerological Data From Metal-Contaminated Sites In Maine, Ian D. Medeiros, Alan M. Fryday, Nishanta Rajakaruna Jan 2014

Additional Lichen Records And Minerological Data From Metal-Contaminated Sites In Maine, Ian D. Medeiros, Alan M. Fryday, Nishanta Rajakaruna

Nishanta Rajakaruna

Geochemistry and mineralogy of rocks play important roles in the occurrence of individual lichen species and assembly of lichen communities. Whereas lichens of metal-enriched settings have been a focus of study for many decades, only a few such lichen inventories exist for North America. We reexamined the lichen biota of Pine Hill, a serpentine outcrop on Little Deer Isle, Maine and Callahan Mine, a copper- and zinc-enriched Superfund site in Brooksville, Maine by conducting additional field surveys and reexamining unidentified taxa from previous collections. To better characterize the substrates upon which the lichens were found, we conducted elemental analyses via ...


Mycorrhizal Colonization Of Hypericum Perforatum L. (Hypericaceae) On Adjacent Serpentine And Granite Outcrops On The Deer Isles, Maine, Usa, N Davoodian, J Bosworth, N Rajakaruna Jan 2012

Mycorrhizal Colonization Of Hypericum Perforatum L. (Hypericaceae) On Adjacent Serpentine And Granite Outcrops On The Deer Isles, Maine, Usa, N Davoodian, J Bosworth, N Rajakaruna

Nishanta Rajakaruna

Given the paucity of literature on plant-fungal interactions on serpentine soils and limited investigation of serpentine geoecology in eastern North America, we examined mycorrhizal colonization of Hypericum perforatum from adjacent serpentine and granite outcrops on the Deer Isles, ME to determine whether plants were differentially colonized based on substrate. We coincided our sampling with three phenologic stages of H. perforatum (preflowering, flowering, postflowering) to determine possible differences in colonization based on plant phenology. The levels of mycorrhizal colonization in H. perforatum were not significantly different between serpentine and granite sites, while levels of colonization in postflowering plants were significantly higher ...


Little Evidence For Local Adaptation To Soils Or Microclimate In The Postfire Recruitment Of Three Californian Shrubs, A Bieger, N Rajakaruna, S P. Harrison Jan 2012

Little Evidence For Local Adaptation To Soils Or Microclimate In The Postfire Recruitment Of Three Californian Shrubs, A Bieger, N Rajakaruna, S P. Harrison

Nishanta Rajakaruna

Background: Seedling recruitment following fire is an infrequent yet critical demographic transition for woody plants in Mediterranean ecosystems. Aims: Here we examine whether post-fire seedling recruitment of three widespread Californian chaparral shrubs is affected by local adaptation within an edaphically and topographically complex landscape. Methods: We reciprocally transplanted 6-month-old seedlings of Adenostema fasciculatum, Ceanothus cuneatus and Eriodictyon californicum to serpentine and sandstone soils, and cool northerly and warm southerly slopes. Results: At the age of 2 years, none of the species manifested higher survival or growth on ‘home’ compared with ‘away’ soils or slopes, indicating an absence of local adaptation ...


Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, T B. Harris, N Rajakaruna, S J. Nelson, P D. Vaux Jan 2012

Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, T B. Harris, N Rajakaruna, S J. Nelson, P D. Vaux

Nishanta Rajakaruna

Stressors and threats to the flora of Acadia National Park, Maine: Current knowledge, information gaps, and future directions. J. Torrey Bot. Soc. 139: 323–344. 2012.— Acadia National Park is a center of plant diversity in northeastern North America. The Park's varied habitats and flora are sensitive to a number of natural and anthropogenic perturbations. Stressors such as invasive plants, pest and pathogens, ozone, acidic fog and sulfur deposition, nitrogen deposition, heavy metals, fire and fire suppression, over-browsing, visitor use, hurricanes, and climate change have all had effects on the Park's habitats and plant species at some point ...


A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Maine, U.S.A, Brett Ciccotelli, Tanner B. Harris, Bruce Connery, Nishanta Rajakaruna Jul 2011

A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Maine, U.S.A, Brett Ciccotelli, Tanner B. Harris, Bruce Connery, Nishanta Rajakaruna

Nishanta Rajakaruna

We conducted a preliminary floristic study of six vernal pools in Acadia National Park on Mount Desert Island, Maine. Plant species were recorded on three sampling dates from April to October, 2008. Sixty-five vascular plant species from 26 families were recorded. Of these, 27 are considered occasional or uncommon in Acadia National Park. Thirteen species are new reports for vernal pools in the northeastern United States. This represents the first published study of the vernal pool flora of Acadia National Park.


Lichens Of Callahan Mine, A Copper And Zinc-Enriched Superfund Site In Brooksville, Maine, U.S.A., Nishanta Rajakaruna, Tanner B. Harris, Stephen R. Clayden, Alison C. Dibble, Fred S. Olday Jan 2011

Lichens Of Callahan Mine, A Copper And Zinc-Enriched Superfund Site In Brooksville, Maine, U.S.A., Nishanta Rajakaruna, Tanner B. Harris, Stephen R. Clayden, Alison C. Dibble, Fred S. Olday

Nishanta Rajakaruna

Metal-enriched habitats often harbor physiologically distinct biotas able to tolerate and accumulate toxic metals. Plants and lichens that accumulate metals have served as effective indicators of ecosystem pollution. Whereas the diversity of metal-tolerant lichens has been well documented globally, the literature of metal-tolerant lichen communities for eastern North America is limited. We examined the lichen flora of the Callahan Mine, a Cu-, Pb-, and Zn-enriched superfund site in Brooksville, Hancock County, Maine, U.S.A. Through collections along transects across metal-contaminated areas of the mine, we documented 76 species of lichens and related fungi. Fifty species were saxicolous, 26 were ...


Vascular Plants Of Adjacent Serpentine And Granite Outcrops On The Deer Isles, Maine, U.S.A, Nathaniel Pope, Tanner B. Harris, Nishanta Rajakaruna Apr 2010

Vascular Plants Of Adjacent Serpentine And Granite Outcrops On The Deer Isles, Maine, U.S.A, Nathaniel Pope, Tanner B. Harris, Nishanta Rajakaruna

Nishanta Rajakaruna

We performed a comparative study of the vascular flora of a serpentine outcrop, Pine Hill, and that of a granite outcrop, Settlement Quarry, from Little Deer Isle and Deer Isle, respectively, Hancock County, Maine. We established four transects along a gradient from exposed to forested areas within each outcrop. Plants were recorded for presence and percent cover from circular plots along each transect. Soil and tissue samples were collected to examine soil-tissue elemental relations. One hundred thirty-two taxa were recorded from serpentine and 89 from granite. Fifty-seven taxa were shared by both sites. Species richness (α diversity) and diversity indices ...


Adiantum Viridimontanum, Aspidotis Densa, Minuartia Marcescens, And Symphyotrichum Rhiannon: Additional Serpentine Endemics From Eastern North America, T B. Harris, N Rajakaruna Jan 2009

Adiantum Viridimontanum, Aspidotis Densa, Minuartia Marcescens, And Symphyotrichum Rhiannon: Additional Serpentine Endemics From Eastern North America, T B. Harris, N Rajakaruna

Nishanta Rajakaruna

Serpentine outcrops around the world are known to harbor disproportionately high rates of plant endemism. Remarkable cases of serpentine endemism occur in New Caledonia and Cuba, with 3178 and 920 endemic taxa, respectively, found solely on serpentine. Despite the patchy occurrence of serpentine in eastern North America from Québec and Newfoundland south to Alabama, only one taxon, Cerastium velutinum var. villosissimum, has been broadly recognized as a serpentine endemic for the region. Based on reports in the literature, we suggest that Adiantum viridimontanum, Minuartia marcescens, and Symphyotrichum rhiannon be considered endemic to serpentine soils from the east coast of North ...


Biology Of Ultramafic Rocks And Soils: Research Goals For The Future, R S. Boyd, A R. Kruckeberg, N Rajakaruna Jan 2009

Biology Of Ultramafic Rocks And Soils: Research Goals For The Future, R S. Boyd, A R. Kruckeberg, N Rajakaruna

Nishanta Rajakaruna

At this, the 6th International Conference on Serpentine Ecology, it seems timely to review briefly the present status of the field and to project the needs for future research. Although a great deal of serpentine research was done prior to 1960, as summarized by Krause (1958) and discussed briefly by Brooks (1987), much of our progress in learning how serpentine geology affects plant and animal life occurred in the mid- to late 20th century. In that era, it was the landmark studies of several scientists worldwide that initiated a meteoric increase in published serpentine research. Key players in setting the ...