Arthur Irving Academy Research Grants in Environmental Science
2017-2018 Research Grant Recipients
Towards an Understanding of Crocanthemum canadense (Rockrose) Biology: A Comparative Analysis of Biotic Challenges and Symbioses Across the North-eastern Range
Dr. Rodger Evans, Department of Biology, Acadia University
Dr. Kirk Hillier, Department of Biology, Acadia University
Dr. Allison Walker, Department of Biology, Acadia University
Crocanthemum canadense (Rockrose) is an herbaceous perennial that is restricted to the dry, sandy barren ecosystems of Nova Scotia, and is listed as critically imperilled in Nova Scotia. Results from a previous study of genetic variation in Northeastern North America Rockrose populations revealed that Nova Scotian populations had the lowest levels of within population variation, and were genetically distinct from the next closest populations in Quebec and Maine.
Rockrose plants produce two types of flowers in the same growing season. Chasmogamous flowers open early in the season and are insect pollinated. Cleistogamous flowers develop later in the season, remain closed, and self pollinate.To gain a better understanding of how the reproductive biology of these different flower types may play a role in genetic diversity, we’ve undertaken several comparative analyses of floral and fruit development in Nova Scotia populations.
During these analyses we observed a novel interact tin between the larva of Mompha cappella and Rockrose chasmogamous flowers. Thew larvae enter developing flowers and sever petals at their bases. The severed petals wilt, causing stamens to come into close contact with the stigma of the pistil. These flowers never open, ands ultimately self pollinate when stamens dehisce inside the severed petals. Early in fruit development the larva chews an entrance and eats most to all of the developing seeds.
Rockrose seeds from previous studies were germinated, and planted out in a bed in the Research Garden area, with the assistance of Dr. Robin Brown (KC Irving Centre) and the Harriet Irving Botanical Garden crew in the autumn of 2015. Although approximately 300 plants were placed in the bed, very few (<30) emerged in 2016 and 2017.
All of our previous research has led us to undertake a variety of new studies in 2018-2019. The first will be to dig up Rockrose plants and analyze their roots and vegetative structures for endosymbiotic fungi. Were hope to gain a better understanding of the role endophytes may play in the growth of Rockrose in this harsh environment, but also use this information to increase success in out plantings in the Harriet Irving Research Gardens.
Secondly, we will undertake a collecting trip throughout the Northeast range of Rockrose that will have two goals. One will be to collect material for a comparative analysis of fungal symbionts across its range, the second will be to collect flower and developing fruit material to determine the extent to which insect larvae may affect planet and reproductive development/output across the range.
Finally, we wish to understand how manipulation of terminal chasmogamous flowers affects plant development later in the season. We will set up several plots at 14 Wing Greenwood and manipulate plants in a manner that reflects Mompha cappella infestation. Some plants will have terminal flowers removed, some will have the petals of terminal flowers glued so that they can’t open, and some will be left as controls, some of which may become infected by M. cappella larvae. At the end of the growing season we will measure plant height, branch number and length, as well as numbers of cleistogamous flowers. Analysis of these data will allow us to infer how removal of terminal chasmogamous flowers affects plant and flower development later in the season.
The Dynamics of Recruitment: Use of Mesocosms to Study Recruitment of Benthic Invertebrates in the Minas Basin Tidal Flats
Dr Glenys Gibson, Department of Biology, Acadia University
Primary objective: to study the recruitment of benthic invertebrates in the Minas Basin, using mesocosm benches at the K.C. Irving Environmental Science Centre.
The Minas Basin is characterized by wide-spread communities of benthic invertebrates that are adapted to the extreme tides that sweep over the tidal flats. The tides create a globally unique environment which subjects small invertebrates to transport of the sediment in which they live and high amounts of suspended sediment that can quickly smother existing communities. Benthic communities in general are maintained by recruitment of larvae, small, planktonic young that feed and grow in the water column, and eventually settle to the bottom where they renew benthic populations. Conditions in the Minas Basin are harsh for most larvae, as strong tidal currents may advect them from favorable habitats and turbidity prevents growth of phytoplankton, their primary food source.
I propose to use the mesocosm benches at the K.C. Irving Environmental Science Centre and Harriet Irving Botanical Gardens in a series of experiments to investigate recruitment processes in locally abundant invertebrate species. The Arthur Irving Academy generously supported a related project in 2015, in which my students and I used the mesocosms to investigate the effects of suspended sediment on benthic invertebrate communities. In our mesocosm experiments, we made an unexpected and interesting discovery- many of these benthic species are highly motile as adults. This contradicts the literature in many cases and suggests that the highly dynamic conditions of the Minas Basin have led to some unusual recruitment processes as well.
Research on larval settlement in soft-sediment communities often uses clean sediment to attract larvae, and while useful, misses the point that larvae in the wild generally settle into an established community. The mesocosms provide us with an ideal opportunity to study larval settlement and adult movement into established communities. This research will provide valuable training for undergraduates in environmental and marine research. This research is relevant to tidal flat communities of the Gulf of Maine- Bay of Fundy Ecosystem, a major coastal ecosystem that is aligned with the Acadia Forest Region. The specific questions address how benthic invertebrates are recruited into tidal flat communities, an important question as these communities are critical food sources to migratory birds and regionally important fishery species.
2016-2017 Research Grant Recipients
Investigation of Lichens as Spatial Indicators of Trace Metal Distribution in Nova Scotia
Dr. Nelson O’Driscoll, Canada Research Chair in Environmental Biogeochemistry, Department of Earth & Environmental Sciences, Acadia University
Dr. John Murimboh, Department of Chemistry, Acadia University
Dr. Allison K. Walker, Department of Biology, Acadia University
Mr. Robert Cameron (lichenologist), Protected Areas Branch, Nova Scotia Department of Environment
Sara Klapstein, PhD Candidate MUN/Acadia
The objective of this research is to examine the spatial distribution of airborne metals across Nova Scotia using lichens as passive air samplers. Nova Scotia is a hotspot for mercury and other trace metal accumulation in ecosystems, a fact that has been partially attributed to long range transport of air pollution. While atmospheric inputs are critical to understanding the impact of contaminants in ecosystems, relatively little is known about regional deposition of trace metals stemming from airborne pollution. Province-wide investigation of metal deposition from the atmosphere is not feasible with current passive air sampling technologies due to the high cost and uncertainty involved. Lichens and mosses have been shown in many studies to be useful bioindicators for airborne metal concentrations. While there are limitations, the proposed techniques are well documented for use in spatial studies to identify areas of high relative average air concentrations and depositional rates of trace metals and other contaminants.
Our first year of data collection (2015-2016) has resulted in more than 300 samples of epiphytic lichens collected from sites across Nova Scotia and resulted in excellent training for an undergraduate researcher, Honours student Cardy Saunders (Biology). This work was generously supported by an Arthur Irving Academy 2016 Research Grant. These samples have been dried, homogenized and analyzed for total mercury concentration in the K.C. Irving Environmental Science Centre. Significant variation in mercury content was observed across sampling sites and GIS analysis was used to display and model these regional trends. This proposed project is a continuation of Year 1 and will make use of the currently collected samples for an additional suite of trace metal analyses (e.g. arsenic, lead, cadmium, etc.) and controlled experiments quantifying the factors affecting mercury adsorption and desorption on the lichen samples. The regional distribution patterns of each metal contaminant will be examined. These data will provide a baseline dataset that can be replicated every 5-10 years to examine changes in the spatial distribution of metal contaminants with changing climate, atmospheric chemistry, and regional pollution sources. The results can also be compared with other recently published spatial surveys of metals in Nova Scotia surface waters and fish. Results of the proposed work will fill a critical knowledge gap in our understanding of continuing pollution distribution in Nova Scotia and Atlantic North America in general. The project emphasizes student training and extensive use of the K.C. Irving Environmental Science Center.
Developing restoration strategies for native plants in Nova Scotia: Investigations of arbuscular mycorrhizal and biochar effects on propagation
Dr. Allison Walker and Dr. Juan Carlos López, Department of Biology, Acadia University
Dr. Robin Browne, K.C. Irving Environmental Science Centre and Harriet Irving Botanical Gardens
Dr Rodger Evans, Department of Biology, Acadia University
Arbuscular mycorrhizal fungi (AMF) are ubiquitous organisms found in terrestrial ecosystems, which often form mutualistic root associations with native plants in their habitats (Smith and Read, 2008). Their role in conservation is understudied, but there is increasing evidence to suggest that AMF enhance native plant persistence in their habitats due to enhanced nutrient availability and increased resistance to abiotic / biotic factors (Smith and Smith, 2012). The proposed study investigates native plant – fungal association, to develop best practices for restoration of vulnerable species, or those of special interest for habitat stabilization. AMF colonization will be investigated for the potential effect on native plants propagated from the seed bank at the K.C. Irving Environmental Science Centre and Harriet Irving Botanical Gardens. Six native plant species considered at risk or of special interest in the Acadian Forest Region have been selected as potential candidates for the study. These species originate from differing habitats, in order to determine a range of possible native mycorrhizal compositions and relative effectiveness of inoculants for improving out-‐planting success. In addition, the effects of biochar are to be investigated for potential benefit, possibly through enhancement of mycorrhizal colonization. This novel application of biochar holds promise as a means of improved establishment of native plants for habitat restoration (Glaser et al., 2014). Notably, the objectives of this project are in compliance with the revised 2011-‐2020 Global Strategy for Plant Conservation Objective 2, Target 8, which seeks to have at least 75% of threatened native plant species in ex situ collections, with at least 20 % available for recovery and restoration programs. The work builds directly on successful Honours thesis work supported by a previous Arthur Irving Academy Foundation Research Grant completed by Irving Scholar Sadie Moland, and with new AMF work in progress by Honours students and Irving Scholars Tyler D’Entremont and Sarah Fancy.
2015-2016 Research Grant Recipients
A multi-faceted approach to understanding the biology of a critically imperiled, Nova Scotia native plant Crocanthemum canadense.
Dr. Rodger Evans & Dr. Kirk Hillier, Department of Biology
Canadian frostweed,Crocanthemum canadense, is a critically endangered native plant growing within Nova Scotia’s sand barren ecosystem. In an effort to examine the factors which impact the fitness of C. canadense populations in Nova Scotia, we raised plants from seeds collected in the wild to experimentally examine reproductive biology of, and effects of insect predation on, C. canadense. Some of the experimental plants are from seeds that arose through insect-mediated cross pollination of open flowers, while others are from seeds that arose from self-pollination in flowers that never open. Knowing the pedigree of the plants allows for comparative measures of genetic variation and plant fitness that can be related back to wild populations. We will also be studying the interactions between the plants and two insect predators. Larvae of Mompha capella eat flower parts before the flowers can open, thus affecting the output of insect pollinated flowers, whereas an as yet undetermined, “seed eating bug” preys upon the seeds of open fruits, and may be damaging the seeds to the point where they don’t germinate. This multifaceted approach will help us better understand the mechanisms this rare plant uses to survive in the harsh environment of Nova Scotia’s sand barrens.
Development of a mobile web app from the recently published e-flora, Nova Scotia Plants.
Dr. Darcy Benoit, Jodrey School of Computer Science
Ruth Newell, E.C. Smith Herbarium
One of the key issues with research is the ability to reference the appropriate research material quickly. In 2014, an electronic book titled “Nova Scotia Plants” was published by Munro, Newell, & Hill. This seven year project was supported by the K.C. Irving Environmental Science Centre at Acadia University and the Nova Scotia Museum. Nova Scotia Plants is an indispensable botanical resource for researchers and students while working with Nova Scotia’s wild flora. Given the size and format of this e-book however, it is not easily accessed via mobile devices. The goal of this project is to make the Nova Scotia Plants e-flora available on mobile devices, allowing both researchers and naturalists easy access to the definitive guide to the flora of the Acadian Forest region. This project will take the existing data from current sources, format the data and insert it into a database, and then use that database to create a mobile web app that allows easy navigation and searching for flora information. Students will be engaged with the development process and with field testing.
Bioaccumulation of Mercury in Lichens and Mushrooms of Nova Scotia
Dr. Allison Walker, Department of Biology
Dr. Nelson O’Driscoll, Department of Earth and Environmental Sciences
Canada Research Chair in Environmental Biogeochemistry
Lichens and mushrooms serve as an important food resource for vertebrate and invertebrate animals in the Acadian forest. Lichens and mushrooms can also bioaccumulate mercury and therefore may be an important mechanism for pollution in terrestrial food webs. Wild mushrooms and lichens from a broad range of sites in Nova Scotia’s Acadian forest will be collected and analyzed for total mercury and methyl mercury. Results of this research will fill a critical gap in our understanding of terrestrial food web dynamics and mercury accumulation in the Acadian forest region of Nova Scotia by studying an often overlooked component of forest biodiversity, lichens and mushrooms. This work will also provide valuable interdisciplinary training for undergraduates in biological and environmental research.
2014-2015 Research Grant Recipients
Sand, Mud and Habitat Engineers: Use of Mesocosms to Study Animal-Sediment Interactions in the Minas Basin
Dr. Glenys Gibson, Department of Biology
The objective of this research is to focus on the interactions between the small invertebrates that live in the nearby Minas Basin’s tidal flats and sediment that is suspended in its waters. The researchers will use the mesocosms at the K.C. Irving Environmental Science Centre to test the effects of suspended sediment on assemblages of marine invertebrates that are typical of sandy or muddy tidal flats in the Minas Basin. These invertebrates are a major source of food for fish and birds, and the potential impact of local water management strategies on them makes the research critically important. The work will also provide valuable training for undergraduates in environmental research focused on the interface between animal-habitat interactions.
Seed and Tissue Bank Research for Native Wetland Plants of the Acadian Forest Region: Strategies to Support the Protection and Restoration of Wetlands
Dr. Rodger Evans, Ruth Newell and Dr. Robin Browne, Department of Biology
Researchers at the K.C. Irving Environmental Science Centre and Acadia University are seeking to make significant contributions toward the conservation of wetland plant species and habitat through the development of seed and tissue bank research programs. The wetland project will involve testing different seed treatments to ensure effective, long-term storage capabilities, as well as developing tissue culture propagation methods to support the production of appropriate numbers and types of planting materials for various conservation and reclamation projects in the Acadian Forest region. Results from these trials will be invaluable for establishing protocols for ongoing conservation activity at the K.C. Irving Environmental Science Centre and will help direct conservation priorities in the Atlantic region. Funding from the Arthur Irving Academy will also support undergraduate research and training opportunities at Acadia University.
Coastal Mycoremediation Pilot Project
Dr. Allison Walker, Department of Biology
Dr. Allison Walker’s mycology lab will conduct a pilot study to determine fungal strains appropriate for hydrocarbon remediation in marine environments, using a tidal mesocosm bench in the K.C. Irving Environmental Science Centre. Native marine fungi will be isolated from intertidal plants, such as saltmarsh and algae, as well as driftwood and intertidal plant detritus. The goal is to identify new fungal species using morphological and molecular techniques and evaluate their effects on oil degradation in marine ecosystems under different environmental conditions. The results of this work could have far-reaching implications for understanding the role of fungi in the breakdown of environmental contaminants in marine ecosystems.