A5090917410- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Microbial Community Ecology and Physiology
- Algal biology and biofuel production
- Isotope Analysis in Ecology
- Aquatic Ecosystems and Phytoplankton Dynamics
- Diatoms and Algae Research
- Protist diversity and phylogeny
- Marine and fisheries research
- Paleontology and Stratigraphy of Fossils
- Marine Bivalve and Aquaculture Studies
- Oil Spill Detection and Mitigation
- Geochemistry and Elemental Analysis
- Marine Toxins and Detection Methods
- Ocean Acidification Effects and Responses
- Food Industry and Aquatic Biology
- Geology and Paleoclimatology Research
- Marine and coastal plant biology
- Toxic Organic Pollutants Impact
- Microbial bioremediation and biosurfactants
- Animal Ecology and Behavior Studies
- Environmental Toxicology and Ecotoxicology
- Mercury impact and mitigation studies
- Physiological and biochemical adaptations
- Species Distribution and Climate Change
Dalhousie University
2001-2024
Mount Allison University
2010-2019
Sackville Memorial Hospital
2017
Rutgers, The State University of New Jersey
2001-2007
Observatoire Océanologique de Banyuls-sur-Mer
2005
Queen's University
2000
Bar-Ilan University
1988
Global increases in atmospheric CO2 and temperature are associated with changes ocean chemistry circulation, altering light nutrient regimes. Resulting phytoplankton community structure expected to have a cascading effect on primary export production, food web dynamics the of marine as well biogeochemical cycling carbon bio-limiting elements sea. A review current literature indicates cell size elemental stoichiometry often respond predictably abiotic conditions follow biophysical rules that...
We analyzed the cellular content of C, N, P, S, K, Mg, Ca, Sr, Fe, Mn, Zn, Cu, Co, Cd, and Mo in 15 marine eukaryotic phytoplankton species culture representing major phyla. All organisms were grown under identical conditions, a medium designed to allow rapid growth while minimizing precipitation iron hydroxide. The concentrations all metals, phosphorus, sulfur determined by high‐resolution inductively coupled plasma mass spectrometry (HR‐ICPMS) those carbon nitrogen hydrogen analyzer....
In many community assemblages, the abundance of organisms is a power-law function organism size. phytoplankton communities, changes in size structure associated with increases resource availability and total biomass have often been interpreted as release from grazer control. A metapopulation-like approach used to scale up individual physiological responses environmental conditions assuming taxonomic composition reflects species pool. We show that scaling cellular nutrient requirements growth...
Anthropogenic climate change has shifted the biogeography and phenology of many terrestrial marine species. Marine phytoplankton communities appear sensitive to change, yet understanding how individual species may respond anthropogenic remains limited. Here, using historical environmental observations, we characterize realized ecological niches for 87 North Atlantic diatom dinoflagellate taxa project changes in between mean (1951-2000) future (2051-2100) ocean conditions. We find that...
The elemental stoichiometry of microalgae reflects their underlying macromolecular composition and influences competitive interactions among species role in the food web biogeochemistry. Here we provide a new estimate using hierarchical Bayesian analysis data compiled from literature. median nutrient-sufficient exponentially growing is 32.2% protein, 17.3% lipid, 15.0% carbohydrate, ash, 5.7% RNA, 1.1% chlorophyll-a 1.0% DNA as percent dry weight. Our identifies significant phylogenetic...
The relative supply of energy and elements available to organisms in the environment has strong effects on their physiology, which, turn, can alter important ecological processes. Here we consider how resource imbalances affect three basic physiological processes common all organisms: elemental uptake, incorporation, release. We review recent research that addresses these core issues (uptake, release) as they relate homeostasis autotrophs heterotrophs. Our shows importance organism plays...
Previous studies have found that the size‐scaling exponent of metabolic rates in unicellular algae often deviates from −1/4 usually for heterotrophs. This study confirms a significant linear relationship between log cell volume (mm 3 ) and intrinsic growth rate (h −1 ), carbon‐normalized photosynthetic capacity performance carbon−normalized respiratory eight marine centric diatoms under nutrient−saturated, light‐limited conditions. The exponents not significantly different −1/4, whereas...
Marine phytoplankton show complex community structures and biogeographic distributions, the net results of physiological ecological trade-offs species responses to fluctuating, heterogeneous environments. We analysed photosynthesis, variable light macromolecular allocations across a size panel marine centric diatoms. The diatoms have strong capacities withstand exploit fluctuating light, when compared with picophytoplankton. Within diatoms, small larger effective cross-sections for...
▪ Abstract The evolutionary succession of marine photoautotrophs began with the origin photosynthesis in Archean Eon, perhaps as early 3.8 billion years ago. Since that time, Earth's atmosphere, continents, and oceans have undergone substantial cyclic secular physical, chemical, biological changes selected for different phytoplankton taxa. Early history eukaryotic algae, between 1.6 1.2 ago, an schism gave rise to “green” (chlorophyll b–containing) “red” c–containing) plastid groups. Members...
Diazotrophic (nitrogen‐fixing) cyanobacteria are important contributors of new nitrogen to oligotrophic environments and greatly influence oceanic productivity. We investigated how iron availability influences the physiology cyanobacterial diazotrophs with different strategies for segregating fixation photosynthesis. examined growth, photosynthesis, fixation, Fe requirements filamentous nonheterocystous Trichodesmium , heterocystous Anabaena unicellular Cyanothece under a range...
Numerous taxonomic groups exhibit an evolutionary trajectory in cell or body size. The size structure of marine phytoplankton communities strongly affects food web and organic carbon export into the ocean interior, yet macroevolutionary patterns have not been previously investigated. We constructed a database silica frustule dominant fossilized planktonic diatom species over Cenozoic. found that minimum maximum sizes expanded concert with increasing diversity. In contrast, mean area is...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 273:269-279 (2004) - doi:10.3354/meps273269 Resource limitation alters 3/4 size scaling of metabolic rates in phytoplankton Zoe V. Finkel1,*, Andrew J. Irwin1,2, Oscar Schofield1 1Institute & Coastal Sciences, Ocean Observation Laboratory, Rutgers University, New Brunswick, Jersey 08901, USA 2Biology...
Marine taxa are threatened by anthropogenic impacts, but knowledge of their extinction vulnerabilities is limited. The fossil record provides rich information on past extinctions that can help predict biotic responses. We show over 23 million years, taxonomic membership and geographic range size consistently explain a large proportion risk variation in six major groups. assess intrinsic risk-extinction predicted paleontologically calibrated models-for modern genera these Mapping the...
Ocean acidification is changing the nature of inorganic carbon availability in global oceans. Diatoms account for µ 40% all marine primary productivity and are major contributors to export atmospheric deep ocean. Larger diatoms more likely be stimulated by future increases CO 2 as a result their low surface area volume ratio lower diffusive flux relative demand growth. Here we quantify effect partial pressure dioxide (P ), at levels 190, 380, 750 µL L −1 , on growth rate, photosystem II...
Significance Most ecosystem models used to predict changes in community composition with climate change assume species’ responses environmental conditions are genetically fixed on the century scale, but this hypothesis has not been tested. Using an oceanographic time series directional changes, we show here that many phytoplankton species able track, average, modest temperature and irradiance, decreases limiting nutrient concentrations, decadal timescales. This result suggests use traits may...
The elemental composition of phytoplankton is a fusion the evolutionary history host and plastid, resulting in differences genetic constraints selection pressures associated with environmental conditions. inheritance hypothesis predicts similarities within related taxonomic lineages phytoplankton. To test this hypothesis, we measured (C, N, P, S, K, Mg, Ca, Sr, Fe, Mn, Zn, Cu, Co, Cd Mo) 14 species combined these published data from 15 more both marine freshwater environments grown under...
We combine phytoplankton occurrence data for 119 species from the continuous plankton recorder with climatological environmental variables in North Atlantic to obtain ecological response functions of each using MaxEnt statistical method. These describe how probability changes as a function conditions and can be reduced simple description realized niches mean standard deviation variable, weighted by its function. Although there was substantial variation niche among within groups, envelope...
Biogeochemical cycles in the ocean are strongly affected by elemental stoichiometry (C:N:P) of phytoplankton, which largely reflects their macromolecular content. A greater understanding how this content varies among phytoplankton taxa and with resource limitation may strengthen physiological biogeochemical modeling efforts. We determined basis (protein, carbohydrate, lipid, nucleic acids, pigments) C:N:P diatoms prasinophytes, two globally important taxa, response to N starvation. Despite...
We have examined the inter‐ and intra‐group seasonal succession of 113 diatom dinoflagellate taxa, as surveyed by Continuous Plankton Recorder (CPR) in North Atlantic, grouping taxa according to two key functional traits: cell size (µg C −1 ) trophic strategy (photoautotrophy, mixotrophy, or heterotrophy). Mixotrophic dinoflagellates follow photoautotrophic diatoms but precede their obligate heterotrophic counterparts because relative advantages afforded photosynthesizing when light...