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Plant Sciences

Selected Works

2012

Peer-Reviewed Publications

Articles 1 - 3 of 3

Full-Text Articles in Entire DC Network

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 …


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 …


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 and it is …