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Climactic Niche Model For Overwintering Monarch Butterflies In A Topographically Complex Region Of California, Ashley Fisher, Kiana Saniee, Charis Van Der Heide, Jessica Griffiths, Daniel Meade, Francis X. Villablanca Nov 2018

Climactic Niche Model For Overwintering Monarch Butterflies In A Topographically Complex Region Of California, Ashley Fisher, Kiana Saniee, Charis Van Der Heide, Jessica Griffiths, Daniel Meade, Francis X. Villablanca

Biological Sciences

We use climatic conditions that are associated with known monarch butterfly overwintering groves in California to build a Maxent model, and focus on the fine scale probability of overwintering grove occurrence in a topographically complex region of the state (Santa Barbara County). Grove locations are known from recent and historical surveys and a long-term citizen science database. The climatic niche model performs well, predicting that overwintering habitat is most likely to occur along the coast and at low elevations, as shown by empirical data. We then use climatic variables in conjunction with climate change scenarios to model the future location ...


Senecio Conrathii N.E.Br. (Asteraceae), A New Hyperaccumulator Of Nickel From Serpentinite Outcrops Of The Barberton Greenstone Belt, South Africa, Stefan Siebert, Nadine Carol Schutte, Stoffel Pieter Bester, Dennis Mmakgabo Komape, Nishanta Rajakaruna May 2018

Senecio Conrathii N.E.Br. (Asteraceae), A New Hyperaccumulator Of Nickel From Serpentinite Outcrops Of The Barberton Greenstone Belt, South Africa, Stefan Siebert, Nadine Carol Schutte, Stoffel Pieter Bester, Dennis Mmakgabo Komape, Nishanta Rajakaruna

Biological Sciences

Five nickel hyperaccumulators belonging to the Asteraceae are known from ultramafic outcrops in South Africa. Phytoremediation applications of the known hyperaccumulators in the Asteraceae, such as the indigenous Berkheya coddii Roessler, are well reported and necessitate further exploration to find additional species with such traits. This study targeted the most frequently occurring species of the Asteraceae on eight randomly selected serpentinite outcrops of the Barberton Greenstone Belt. Twenty species were sampled, including 12 that were tested for nickel accumulation for the first time. Although the majority of the species were excluders, the known hyperaccumulators Berkheya nivea N.E.Br. and ...


Biological Crusts Of Serpentine And Non-Serpentine Soils From The Barberton Greenstone Belt Of South Africa, Arthurita Venter, Stefan Siebert, Nishanta Rajakaruna, Sandra Barnard, Anatoliy Levanets, Arshad Ismail, Mushal Allam, Bianca Peterson, Tomasz Sanko May 2018

Biological Crusts Of Serpentine And Non-Serpentine Soils From The Barberton Greenstone Belt Of South Africa, Arthurita Venter, Stefan Siebert, Nishanta Rajakaruna, Sandra Barnard, Anatoliy Levanets, Arshad Ismail, Mushal Allam, Bianca Peterson, Tomasz Sanko

Biological Sciences

Climate and geography can influence biological soil crust (BSC) community composition, but local heterogeneity in variables such as soil characteristics or microclimate gradients can also impact cryptogamic diversity. Heavy metals and nutrient imbalances in serpentine soils are known to influence the distributions of higher plants, but cryptogamic species appear to be more tolerant of substrate. The aim of this study was to compare the cryptogamic composition of serpentine and non-serpentine soils by using integrative taxonomy, which combines morphological and DNA barcoding data, to determine how soil characteristics in combination with rainfall can influence BSC community composition. Samples from serpentine and ...


Lessons On Evolution From The Study Of Edaphic Specialization, Nishanta Rajakaruna Mar 2018

Lessons On Evolution From The Study Of Edaphic Specialization, Nishanta Rajakaruna

Biological Sciences

Plants adapted to special soil types are ideal for investigating evolutionary processes, including maintenance of intraspecific variation, adaptation, reproductive isolation, ecotypic differentiation, and the tempo and mode of speciation. Common garden and reciprocal transplant approaches show that both local adaptation and phenotypic plasticity contribute to edaphic (soil-related) specialization. Edaphic specialists evolve rapidly and repeatedly in some lineages, offering opportunities to investigate parallel evolution, a process less commonly documented in plants than in animals. Adaptations to soil features are often under the control of major genes and they frequently have direct or indirect effects on genes that contribute to reproductive isolation ...


Effect Of The Specific Carbohydrate Diet On The Microbiome Of A Primary Sclerosing Cholangitis And Ulcerative Colitis Patient, Alanna Dubrovsky, Christopher Kitts Feb 2018

Effect Of The Specific Carbohydrate Diet On The Microbiome Of A Primary Sclerosing Cholangitis And Ulcerative Colitis Patient, Alanna Dubrovsky, Christopher Kitts

Biological Sciences

A 20-year-old female was diagnosed with ulcerative colitis (UC) at age 14 and primary sclerosing cholangitis (PSC) at age 16. The PSC was successfully treated with high doses of oral vancomycin; however, the UC was more difficult to manage. After many drug treatments failed to treat the UC, the patient began following the specific carbohydrate diet (SCD). This report documents fecal microbiome changes resulting from following the SCD for two weeks. The DNA extracted from fecal samples was subjected to 16S rRNA gene sequencing to quantify bacterial species abundance. Not only were substantial changes in the fecal bacterial composition detectable ...


Heavy Metals In Seaweeds From A Polluted Estuary In Coastal Maine, Ian D. Medeiros, Arthur C. Mathieson, Nishanta Rajakaruna Jul 2017

Heavy Metals In Seaweeds From A Polluted Estuary In Coastal Maine, Ian D. Medeiros, Arthur C. Mathieson, Nishanta Rajakaruna

Biological Sciences

Seaweeds (macroalgae) accumulate heavy metals from seawater and can therefore serve as biological monitors of marine pollution. In this paper, we present data on the tissue chemistry of seaweeds from the area of Callahan Mine, an intertidal copper and zinc mine in Brooksville, ME, USA, abandoned in the 1970s and now designated as a Superfund site. The mine is located on the Goose Pond estuary, which drains into the ocean via a tidal waterfall at Goose Falls. Seaweed tissue samples from this estuary had the same relative concentrations of metals as had been reported previously in water samples from this ...


Ultramafic Geoecology Of South And Southeast Asia, M.L. Galey, A. Van Der Ent, M.C.M. Iqbal, N. Rajakaruna Apr 2017

Ultramafic Geoecology Of South And Southeast Asia, M.L. Galey, A. Van Der Ent, M.C.M. Iqbal, N. Rajakaruna

Biological Sciences

Globally, ultramafic outcrops are renowned for hosting foras with high levels of endemism, including plants with specialised adaptations such as nickel or manganese hyperaccumulation. Soils derived from ultramafic regoliths are generally nutrient-deficient, have major cation imbalances, and have concomitant high concentrations of potentially phytotoxic trace elements, especially nickel. The South and Southeast Asian region has the largest surface occurrences of ultramafic regoliths in the world, but the geoecology of these outcrops is still poorly studied despite severe conservation threats. Due to the paucity of systematic plant collections in many areas and the lack of georeferenced herbarium records and databased information ...


The Alpine Vascular Plants Of Baxter State Park, Maine, Usa, Abigail J. Urban, Glen H. Mittelhauser, Matthew Dickinson, N. Rajakaruna Apr 2017

The Alpine Vascular Plants Of Baxter State Park, Maine, Usa, Abigail J. Urban, Glen H. Mittelhauser, Matthew Dickinson, N. Rajakaruna

Biological Sciences

We conducted 12 days of field surveys on five mountains over 1100 m in elevation (Katahdin, North Brother, South Brother, Mount Coe, and The Owl) in Baxter State Park (BSP), Maine during the summers of 2013–14. In addition, we examined historic manuscripts, unpublished data, and herbarium records for plant records from the five mountains. Katahdin, the largest and tallest of the five mountains, has a rich history of botanical exploration and we documented 1559 herbarium vouchers that were collected from the mountain, primarily before the mid-1900s. Combining all data sources, we documented 38 families, 87 genera, and 131 taxa ...


Role Of Woody Biochar And Fungal-Bacterial Co-Inoculation On Enzyme Activity And Metal Immobilization In Serpentine Soil, Tharanga Bandara, Indika Herath, Prasanna Kumarathilaka, Mihiri Seneviratne, Gamini Seneviratne, Nishanta Rajakaruna, Meththika Vithanage, Yong Sik Ok Mar 2017

Role Of Woody Biochar And Fungal-Bacterial Co-Inoculation On Enzyme Activity And Metal Immobilization In Serpentine Soil, Tharanga Bandara, Indika Herath, Prasanna Kumarathilaka, Mihiri Seneviratne, Gamini Seneviratne, Nishanta Rajakaruna, Meththika Vithanage, Yong Sik Ok

Biological Sciences

Purpose

In this study, we investigated the effect of biochar (BC) and fungal bacterial co-inoculation (FB) on soil enzymatic activity and immobilization of heavy metals in serpentine soil in Sri Lanka.

Materials and methods

A pot experiment was conducted with tomatoes (Lycopersicon esculentum L.) at 1, 2.5, and 5 % (w/w) BC ratios. Polyphenol oxidase, catalase and dehydrogenase activities were determined by idometric, potassium permanganate oxidisable, and spectrophotometric methods, respectively. Heavy metal concentrations were assessed by 0.01 M CaCl2 and sequential extraction methods.

Results and discussion

An increase in BC application reduced polyphenol oxidase, dehydrogenase, and catalase ...


Drivers Of Redistribution Of fishing And Non-fishing Effort After The Implementation Of A Marine Protected Area Network, Reniel B. Cabral, Steven D. Gaines, Brett A. Johnson, Tom W. Bell, Crow White Feb 2017

Drivers Of Redistribution Of fishing And Non-fishing Effort After The Implementation Of A Marine Protected Area Network, Reniel B. Cabral, Steven D. Gaines, Brett A. Johnson, Tom W. Bell, Crow White

Biological Sciences

Marine spatial planning (MSP) is increasingly utilized to sustainably manage ocean uses. Marine protected areas (MPAs), a form of spatial management in which parts of the ocean are regulated to fishing, are now a common tool in MSP for conserving marine biodiversity and managing fisheries. However, the use of MPAs in MSP often neglects, or simplifies, the redistribution of fishing and non-fishing activities inside and outside of MPAs following their implementation. This redistribution of effort can have important implications for effective MSP. Using long-term (14 yr) aerial surveys of boats at the California Channel Islands, we examined the spatial redistribution ...


Plant Growth Promotion By Bradyrhizobium Japonicum Under Heavy Metal Stress, M. Seneviratne, S. Gunaratne, T. Bandara, L. Weerasundara, Nishanta Rajakaruna, G. Seneviratne, M. Vithanage Jul 2016

Plant Growth Promotion By Bradyrhizobium Japonicum Under Heavy Metal Stress, M. Seneviratne, S. Gunaratne, T. Bandara, L. Weerasundara, Nishanta Rajakaruna, G. Seneviratne, M. Vithanage

Biological Sciences

The increase in usage of heavy metals in different industrial activities causes their existence in effluents. Excessive concentrations of these heavy metals pollute soil and water. Heavy metals cause toxicities and other harmful effects not only in humans and animals but also in plants and soil microorganisms. Heavy metals disrupt many biochemical and physiological activities in bacteria, including growth, development, enzyme and hormone production. Indole acetic acid (IAA) is one of the most important hormones in plants, which is secreted by both bacteria and plants. The present study assessed the effects of Ni, Pb and Cu on the growth of ...


Limestone Flora Of The Simonton Corner Quarry Preserve, Rockport, Maine, Usa, Margaret Stern, Ian D. Medeiros, Luka Negoita, N. Rajakaruna May 2016

Limestone Flora Of The Simonton Corner Quarry Preserve, Rockport, Maine, Usa, Margaret Stern, Ian D. Medeiros, Luka Negoita, N. Rajakaruna

Biological Sciences

Limestone is a distinctive substrate that has significant effects on soils and plants. The present study characterizes the diversity of vascular plants, bryophytes, and lichens at the Simonton Corner Quarry Preserve, an abandoned limestone quarry in Rockport, Maine, USA, which was in operation in the late 1800s. We document vascular plant diversity and associated edaphic features (i.e., soil pH and elemental chemistry) using 30 535 meter plots spread throughout the site. For vascular plants, 114 species in 96 genera and 50 families were observed; few of these species are known to prefer calcareous environments, and 38% are nonnative. Conversely ...


A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen H. Mittlehauser, N. Rajakaruna Apr 2016

A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen H. Mittlehauser, N. Rajakaruna

Biological Sciences

Strong environmental gradients and varied land-use practices have generated a mosaic of habitats harboring distinct plant communities on islands on the coast of Maine. Botanical studies of Maine’s islands, however, are generally limited in number and scope. Baseline studies of Maine’s islands are necessary for assessing vegetation dynamics and changes in habitat conditions in relation to environmental impacts imposed by climate change, rising sea levels, invasive species, pests and pathogens, introduced herbivores, and human disturbance. We conducted a survey of the vascular plants and soils of forest, field, and ocean-side communities of Great Duck and Little Duck Islands ...


Resource Partitioning Along Multiple Niche Axes Drives Functional Diversity In Parrotfishes On Caribbean Coral Reefs, Thomas C. Adam, Megan Kelley, Benjamin I. Ruttenberg, Deron E. Burkepile Dec 2015

Resource Partitioning Along Multiple Niche Axes Drives Functional Diversity In Parrotfishes On Caribbean Coral Reefs, Thomas C. Adam, Megan Kelley, Benjamin I. Ruttenberg, Deron E. Burkepile

Biological Sciences

The recent loss of key consumers to exploitation and habitat degradation has significantly altered community dynamics and ecosystem function across many ecosystems worldwide. Predicting the impacts of consumer losses requires knowing the level of functional diversity that exists within a consumer assemblage. In this study, we document functional diversity among nine species of parrotfishes on Caribbean coral reefs. Parrotfishes are key herbivores that facilitate the maintenance and recovery of coral-dominated reefs by controlling algae and provisioning space for the recruitment of corals. We observed large functional differences among two genera of parrotfishes that were driven by differences in diet. Fishes ...


Complete Mitochondrial Genome Of The Speckled Dace Rhinichthys Osculus, A Widely Distributed Cyprinid Minnow Of Western North America, Samantha J. Bock, Morgan M. Malley, Sean Lema Oct 2015

Complete Mitochondrial Genome Of The Speckled Dace Rhinichthys Osculus, A Widely Distributed Cyprinid Minnow Of Western North America, Samantha J. Bock, Morgan M. Malley, Sean Lema

Biological Sciences

The speckled dace Rhinichthys osculus (order Cypriniformes), also known as the carpita pinta, is a small cyprinid minnow native to western North America. Here, we report the sequencing of the full mitochondrial genome (mitogenome) of R. osculus from a male fish collected from the Amargosa River Canyon in eastern California, USA. The assembled mitogenome is 16 658 base pair (bp) nucleotides, and encodes 13 protein-coding genes, and includes both a 12S and a 16S rRNA, 22 tRNAs, and a 985 bp D-loop control region. Mitogenome synteny reflects that of other Ostariophysian fishes with the majority of genes and RNAs encoded ...


Temperatures Experienced By Fresh-Cut Leafy Greens During Retail Storage And Display, W. Brown, E. Ryser, L. Gorman, Scott J. Steinmaus, Keith Vorst Sep 2015

Temperatures Experienced By Fresh-Cut Leafy Greens During Retail Storage And Display, W. Brown, E. Ryser, L. Gorman, Scott J. Steinmaus, Keith Vorst

Biological Sciences

There has been limited published work in the United States on temperature profiling of fresh-cut, bagged leafy greens during their transport, retail storage, and retail display. This study utilized temperature monitors placed in backrooms and display cases at nine supermarkets located in southern California: the Central Coast (Santa Barbara to Los Osos), Greater Los Angeles (Burbank area), and Greater Palm Desert. Sensors were installed midway along each 8-foot display case section containing fresh-cut leafy greens. Monitors were placed at the front and back of shelves and in the lower bin. In storage rooms, sensors were placed 4 feet from the ...


Introduction Next Contents Vol 63(4) Global Research On Ultramafic (Serpentine) Ecosystems (8th International Conference On Serpentine Ecology In Sabah, Malaysia), Antony Van Der Ent, Nishanta Rajakaruna, Robert Boyd, Guillaume Echevarria, Rimi Repin, Dick Williams Jun 2015

Introduction Next Contents Vol 63(4) Global Research On Ultramafic (Serpentine) Ecosystems (8th International Conference On Serpentine Ecology In Sabah, Malaysia), Antony Van Der Ent, Nishanta Rajakaruna, Robert Boyd, Guillaume Echevarria, Rimi Repin, Dick Williams

Biological Sciences

Since 1991, researchers from approximately 45 nations have participated in eight International Conferences on Serpentine Ecology (ICSE). The ICSE conferences are coordinated by the International Serpentine Ecology Society (ISES), a formal research society whose members study geological, pedological, biological and applied aspects of ultramafic ecosystems worldwide. These conferences have provided an international forum to discuss and synthesise multidisciplinary research, and have provided opportunities for scientists in distinct fields and from different regions of the world to conduct collaborative and interdisciplinary research. The 8th ICSE was hosted by Sabah Parks in Malaysia, on the island of Borneo, and attracted the largest ...


Global Research On Ultramafic (Serpentine) Ecosystems (8th International Conference On Serpentine Ecology In Sabah, Malaysia): A Summary And Synthesis, Antony Van Der Ent, Nishanta Rajakaruna, Robert Boyd, Guillaume Echevarria, Rimi Repin, Dick Williams May 2015

Global Research On Ultramafic (Serpentine) Ecosystems (8th International Conference On Serpentine Ecology In Sabah, Malaysia): A Summary And Synthesis, Antony Van Der Ent, Nishanta Rajakaruna, Robert Boyd, Guillaume Echevarria, Rimi Repin, Dick Williams

Biological Sciences

Since 1991, researchers from approximately 45 nations have participated in eight International Conferences on Serpentine Ecology (ICSE). The Conferences are coordinated by the International Serpentine Ecology Society (ISES), a formal research society whose members study geological, pedological, biological and applied aspects of ultramafic (serpentine) ecosystems worldwide. These conferences have provided an international forum to discuss and synthesise multidisciplinary research, and have provided opportunities for scientists in distinct fields and from different regions of the world to conduct collaborative and interdisciplinary research. The 8th ICSE was hosted by Sabah Parks in Malaysia, on the island of Borneo, and attracted the largest ...


Role Of Bacterial-Fungal Interactions On Heavy Metal Phytotoxicity In Serpentine Soil, Mihiri Seneviratne, Gamini Seneviratne, H. M. S. P. Madawala, M.C.M. Iqbal, Nishanta Rajakaruna, Tharanga Bandara, Meththika Vithanage Apr 2015

Role Of Bacterial-Fungal Interactions On Heavy Metal Phytotoxicity In Serpentine Soil, Mihiri Seneviratne, Gamini Seneviratne, H. M. S. P. Madawala, M.C.M. Iqbal, Nishanta Rajakaruna, Tharanga Bandara, Meththika Vithanage

Biological Sciences

This study was conducted to understand the role of bacterial–fungal interactions on heavy metal uptake by Zea mays plants. A pot experiment was conducted for 90 days with Z. mays in serpentine soil inoculated with a Gram-negative bacterium, fungus (Aspergilllus sp.) and both microbes to determine the effects of inoculation on nickel, manganese, chromium and cobalt concentrations in plant tissue and soil. Soil nutrients and soil enzyme activities were measured to determine the effect of inoculations on soil quality. Inoculation of microorganisms increased shoot and root biomass, and the maximum biomass was in the bacterial–fungal inoculation. This could ...


Calcium : Magnesium Ratio Affects Environmental Stress Sensitivity In The Serpentine-Endemic Alyssum Inflatum (Brassicaceae), Rasoul Ghasemi, Zohreh Zare Chavoshi, Robert S. Boyd, Nishanta Rajakaruna Apr 2015

Calcium : Magnesium Ratio Affects Environmental Stress Sensitivity In The Serpentine-Endemic Alyssum Inflatum (Brassicaceae), Rasoul Ghasemi, Zohreh Zare Chavoshi, Robert S. Boyd, Nishanta Rajakaruna

Biological Sciences

Plants endemic to serpentine soils are adapted to harsh environmental conditions typical of those soils, particularly, low (<1) calcium (Ca) : magnesium (Mg) ratios. We compared survival of two perennial Alyssum species native to Iran under experimental manipulations of Ca : Mg ratio, including when Ca : Mg ratio was varied under conditions of high ammonium concentration and heat stress. Alyssum inflatum is a serpentine endemic capable of nickel (Ni) hyperaccumulation, whereas A. lanceolatum is found on non-serpentine soils and is not known to hyperaccumulate Ni. We grew plants of both species under four Ca : Mg ratios (0.4, 2, 20, 40) and tested survival when plants were exposed to elevated ammonium levels (0, 1 ...


A Preliminary Survey Of The Diversity Of Soil Algae And Cyanoprokaryotes On Mafic And Ultramafic Substrates In South Africa, Arthurita Venter, Anatoliy Levanets, Stefan Siebert, Nishanta Rajakaruna Apr 2015

A Preliminary Survey Of The Diversity Of Soil Algae And Cyanoprokaryotes On Mafic And Ultramafic Substrates In South Africa, Arthurita Venter, Anatoliy Levanets, Stefan Siebert, Nishanta Rajakaruna

Biological Sciences

Despite a large body of work on the serpentine-substrate effect on vascular plants, little work has been undertaken to describe algal communities found on serpentine soils derived from peridotite and other ultramafic rocks. We report a preliminary study describing the occurrence of algae and cyanoprokaryotes on mafic and ultramafic substrates from South Africa. Results suggest that slope and aspect play a key role in species diversity and community composition and, although low pH, nutrients and metal content do not reduce species richness, these edaphic features also influence species composition. Further, typical soil genera such as Leptolyngbya, Microcoleus, Phormidium, Chlamydomonas, Chlorococcum ...


Transfer Of Heavy Metals Through Terrestrial Food Webs: A Review, Jillian E. Gall, Robert Boyd, Nishanta Rajakaruna Apr 2015

Transfer Of Heavy Metals Through Terrestrial Food Webs: A Review, Jillian E. Gall, Robert Boyd, Nishanta Rajakaruna

Biological Sciences

Heavy metals are released into the environment by both anthropogenic and natural sources. Highly reactive and often toxic at low concentrations, they may enter soils and groundwater, bioaccumulate in food webs, and adversely affect biota. Heavy metals also may remain in the environment for years, posing long-term risks to life well after point sources of heavy metal pollution have been removed. In this review, we compile studies of the community-level effects of heavy metal pollution, including heavy metal transfer from soils to plants, microbes, invertebrates, and to both small and large mammals (including humans). Many factors contribute to heavy metal ...


Vegetation Dynamics And Mesophication In Response To Conifer Encroachment Within An Ultramafic System, J. Burgess, K. Szlavecz, N. Rajakaruna, S. Lev, C. Swan Apr 2015

Vegetation Dynamics And Mesophication In Response To Conifer Encroachment Within An Ultramafic System, J. Burgess, K. Szlavecz, N. Rajakaruna, S. Lev, C. Swan

Biological Sciences

The biological, ecological, and evolutionary significance of serpentine habitats has long been recognised. We used an integrated physiochemical dataset combining plot spatial data with temporal data from tree cores to evaluate changes in soils and vegetation. Data suggest that this unique habitat is undergoing a transition, endangering local biodiversity and endemic plant species. The objective of this work was to analyse the vegetation dynamics of a xeric serpentine savanna located in the Mid-Atlantic, USA. We employed vegetation surveys of 32 10 × 15 m quadrats to obtain woody species composition, density, basal area, and developed a spatial physiochemical dataset of substrate ...


Growth And Nickel Uptake By Serpentine And Non-Serpentine Populations Of Fimbristylis Ovata (Cyperaceae) From Sri Lanka, P. K. D. Chathuranga, S. K. A. T. Dharmasena, Nishanta Rajakaruna, M.C.M. Iqbal Apr 2015

Growth And Nickel Uptake By Serpentine And Non-Serpentine Populations Of Fimbristylis Ovata (Cyperaceae) From Sri Lanka, P. K. D. Chathuranga, S. K. A. T. Dharmasena, Nishanta Rajakaruna, M.C.M. Iqbal

Biological Sciences

Compared with serpentine floras of Southeast Asia, the serpentine vegetation of Sri Lanka is impoverished in regard to serpentine endemics and nickel hyperaccumulators. All species so far documented from the serpentine outcrops of Sri Lanka also have non-serpentine populations; it is unclear whether the serpentine populations are physiologically distinct and deserve ecotypic recognition. We conducted a preliminary study to examine whether serpentine and non-serpentine populations of Fimbristylis ovata represent locally adapted ecotypes by investigating their growth and potential for nickel uptake and tolerance under greenhouse conditions. Although both populations of F. ovata showed a similar growth pattern in serpentine soil ...


Ecotypic Differentiation Of Mid-Atlantic Quercus Species In Response To Ultramafic Soils, Jerry Burgess, Katalin Szlavecz, Nishanta Rajakaruna, Christopher Swan Mar 2015

Ecotypic Differentiation Of Mid-Atlantic Quercus Species In Response To Ultramafic Soils, Jerry Burgess, Katalin Szlavecz, Nishanta Rajakaruna, Christopher Swan

Biological Sciences

Spatial heterogeneity of soil conditions combined with intraspecific variation confer site-specific edaphic tolerance, resulting in local adaptation and speciation. To understand the geoecological processes controlling community assembly of woodland tree species on serpentine and mafic soils, we investigated resource gradients and provenance (geographic area of propagule collection) as variables affecting typical representative upland oak (Quercus) species distribution. Accordingly, we conducted a year-long reciprocal transplant experiment in the greenhouse with serpentine and mafic soils, using seedlings of five oak species (Quercus marilandica, Q. stellata, Q. montana, Q. michauxii and Q. alba). All seedlings, regardless of provenance or soil depth, displayed more ...


Herbivory And The Resilience Of Caribbean Coral Reefs: Knowledge Gaps And Implications For Management, Thomas C. Adam, Deron E. Burkepile, Benjamin I. Ruttenberg, Michelle J. Paddack Feb 2015

Herbivory And The Resilience Of Caribbean Coral Reefs: Knowledge Gaps And Implications For Management, Thomas C. Adam, Deron E. Burkepile, Benjamin I. Ruttenberg, Michelle J. Paddack

Biological Sciences

Herbivory is a key process on coral reefs that can facilitate reef-building corals by excluding algae that otherwise negatively impact coral settlement, growth, and survivorship. Over the last several decades, coral cover on Caribbean reefs has declined precipitously. On many reefs, large structurally complex corals have been replaced by algae and other non-reef-building organisms, resulting in the collapse of physical structure and the loss of critical ecosystem services. The drivers of coral decline on Caribbean reefs are complex and vary among locations. On many reefs, populations of key herbivores have been greatly reduced by disease and overfishing, and this has ...


Protemic Identification Of Germline Proteins In Caenorhabditis Elegans, B Elizabeth Turner, Sophia M. Basecke, Grace E. Bazan, Eric S. Dodge, Cassy M. Haire, Dylan J. Heussman, Chelsey L. Johnson, Chelsea K. Mukai, Adrianna M. Naccarati, Sunny-June Norton, Jennifer R. Sato, Chihara O. Talavera, Michael V. Wade, Kenneth J. Hillers Jan 2015

Protemic Identification Of Germline Proteins In Caenorhabditis Elegans, B Elizabeth Turner, Sophia M. Basecke, Grace E. Bazan, Eric S. Dodge, Cassy M. Haire, Dylan J. Heussman, Chelsey L. Johnson, Chelsea K. Mukai, Adrianna M. Naccarati, Sunny-June Norton, Jennifer R. Sato, Chihara O. Talavera, Michael V. Wade, Kenneth J. Hillers

Biological Sciences

Sexual reproduction involves fusion of 2 haploid gametes to form diploid offspring with genetic contributions from both parents. Gamete formation represents a unique developmental program involving the action of numerous germline-specific proteins. In an attempt to identify novel proteins involved in reproduction and embryonic development, we have carried out a proteomic characterization of the process in Caenorhabditis elegans. To identify candidate proteins, we used 2D gel electrophoresis (2DGE) to compare protein abundance in nucleus-enriched extracts from wild-type C. elegans, and in extracts from mutant worms with greatly reduced gonads (glp-4(bn2) worms reared at 25°C); 84 proteins whose abundance ...


Immobilization And Phytotoxicity Reduction Of Heavy Metals In Serpentine Soil Using Biochar, I. Herath, P. Kumarathilaka, A. Navarantne, N. Rajakaruna, M. Vithanage Jan 2015

Immobilization And Phytotoxicity Reduction Of Heavy Metals In Serpentine Soil Using Biochar, I. Herath, P. Kumarathilaka, A. Navarantne, N. Rajakaruna, M. Vithanage

Biological Sciences

Purpose

Serpentine soils derived from ultramafic rocks release elevated concentrations of toxic heavy metals into the environment. Hence, crop plants cultivated in or adjacent to serpentine soil may experience reduced growth due to phytotoxicity as well as accumulate toxic heavy metals in edible tissues. We investigated the potential of biochar (BC), a waste byproduct of bioenergy industry in Sri Lanka, as a soil amendment to immobilize Ni, Cr, and Mn in serpentine soil and minimize their phytotoxicity.

Materials and methods

The BC used in this study was a waste byproduct obtained from a Dendro bioenergy industry in Sri Lanka. This ...


Diversity And Soil-Tissue Elemental Relations Of Vascular Plants Of Callahan Mine, Brooksville, Maine, U.S.A., Margaret R. Mansfield, Nathaniel S. Pope, Glen H. Mittelhauser, Nishanta Rajakaruna Sep 2014

Diversity And Soil-Tissue Elemental Relations Of Vascular Plants Of Callahan Mine, Brooksville, Maine, U.S.A., Margaret R. Mansfield, Nathaniel S. Pope, Glen H. Mittelhauser, Nishanta Rajakaruna

Biological Sciences

Metal-contaminated soils provide numerous stressors to plant life, resulting in unique plant communities worldwide. The current study focuses on the vascular plants of Callahan Mine in Brooksville, ME, USA, a Superfund site contaminated with Cu, Zn, Pb, and other pollutants. One hundred and fifty-five taxa belonging to 50 families were identified, with the Asteraceae (21%), Poaceae (11%), and Rosaceae (9%) as the most species-rich families. Ninety-six species encountered at the Mine were native to North America (62%), including 11 taxa (7%) with rarity status in at least one New England state. Fifty-one species were non-native (33%), including nine taxa (6 ...


Metal Release From Serpentine Soils In Sri Lanka, Meththika Vithanage, Anushka Upamali Rajapaksha, Christopher Oze, Nishanta Rajakaruna, C. B. Dissanayake Jun 2014

Metal Release From Serpentine Soils In Sri Lanka, Meththika Vithanage, Anushka Upamali Rajapaksha, Christopher Oze, Nishanta Rajakaruna, C. B. Dissanayake

Biological Sciences

Ultramafic rocks and their related soils (i.e., serpentine soils) are non-anthropogenic sources of metal contamination. Elevated concentrations of metals released from these soils into the surrounding areas and groundwater have ecological-, agricultural-, and human health-related consequences. Here we report the geochemistry of four different serpentine soil localities in Sri Lanka by coupling interpretations garnered from physicochemical properties and chemical extractions. Both Ni and Mn demonstrate appreciable release in water from the Ussangoda soils compared to the other three localities, with Ni and Mn metal release increasing with increasing ionic strengths at all sites. Sequential extraction experiments, utilized to identify ...