Physical Sciences and Mathematics Commons^™

Phytoplankton Thermal Trait Parameterization Alters Community Structure And Biogeochemical Processes In A Modeled Ocean, Stephanie I. Anderson, Clara Fronda, Andrew D. Barton, Sophie Clayton, Tatiana A. Rynearson, Stephanie Dutkiewicz

OES Faculty Publications

Phytoplankton exhibit diverse physiological responses to temperature which influence their fitness in the environment and consequently alter their community structure. Here, we explored the sensitivity of phytoplankton community structure to thermal response parameterization in a modelled marine phytoplankton community. Using published empirical data, we evaluated the maximum thermal growth rates (μ_max) and temperature coefficients (Q₁₀; the rate at which growth scales with temperature) of six key Phytoplankton Functional Types (PFTs): coccolithophores, cyanobacteria, diatoms, diazotrophs, dinoflagellates, and green algae. Following three well-documented methods, PFTs were either assumed to have (1) the same μ_max and …

Potential Interactions Between Diatoms And Bacteria Are Shaped By Trace Element Gradients In The Southern Ocean, Alexa R. Sterling, Laura Z. Holland, Randelle M. Bundy, Shannon M. Burns, Kristen N. Buck, P. Dreux Chappell, Bethany D. Jenkins

OES Faculty Publications

The growth of diatoms in the Southern Ocean, especially the region surrounding the West Antarctic Peninsula, is frequently constrained by low dissolved iron and other trace metal concentrations. This challenge may be overcome by mutualisms between diatoms and co-occurring associated bacteria, in which diatoms produce organic carbon as a substrate for bacterial growth, and bacteria produce siderophores, metal-binding ligands that can supply diatoms with metals upon uptake as well as other useful secondary compounds for diatom growth like vitamins. To examine the relationships between diatoms and bacteria in the plankton (diatom) size class (> 3 mu m), we sampled both …

Examining Ecological Succession Of Diatoms In California Current System Cyclonic Mesoscale Eddies, Zuzanna M. Abdala, Sophie Clayton, Sveinn V. Einarsson, Kimberly Powell, Claire P. Till, Tyler H. Coale, P. Dreux Chappell

OES Faculty Publications

The California Current System is a diatom-dominated region characterized by seasonal coastal upwelling and additional elevated mesoscale activity. Cyclonic mesoscale eddies in the region trap productive coastal waters with their planktonic communities and transport them offshore with limited interaction with surrounding waters, effectively acting as natural mesocosms, where phytoplankton populations undergo ecological succession as eddies age. This study examines diatom community composition within two mesoscale cyclonic eddies that formed in the same region of the California Current System 2 months apart and in the California Current waters surrounding them. The diatom communities were analyzed in the context of shifting environmental …

Seasonal And Interannual Variability Of Phytoplankton Abundance And Community Composition On The Central Coast Of California, Alex Barth, Ryan K. Walter, Ian C. Robbins, Alexis Pasulka

Physics

Variations in the abundance and composition of phytoplankton greatly impact ecosystem structure and function. Within the California Current System (CCS), phytoplankton community structure is tightly coupled to seasonal variability in wind-driven coastal upwelling, a process that drives changes in coastal water temperatures and nutrient concentrations. Based on approximately a decade (2008-2018) of weekly phytoplankton measurements, this study provides the first characterization of the seasonal and interannual variability of phytoplankton abundance and composition in San Luis Obispo (SLO) Bay, an understudied region within the CCS. Overall, the seasonality of phytoplankton in SLO Bay mirrored that of the larger CCS; diatoms dominated …

Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

An ecosystem’s ability to maintain structure and function following disturbance, defined as resilience, is influenced by a hierarchy of environmental controls, including climate, surface cover, and ecological relationships that shape biological community composition and productivity. This study examined lacustrine sediment records of naturally fishless lakes in Yellowstone National Park to reconstruct the response of aquatic communities to climate and trophic cascades from fish stocking. Sediment records of diatom algae did not exhibit a distinct response to fish stocking in terms of assemblage or algal productivity. Instead, 3 of 4 lakes underwent a shift to dominance by benthic diatom species from …

A Climatological Dataset Of Nutrient, Chlorophyll, And Particulate Matter Distributions On The Ross Sea Continental Shelf Derived From Cruise-Based Measurements Spanning 1967 To 2016, Walker O. Smith Jr., Daniel E. Kaufman

Data

This dataset includes data used in the publication Smith and Kaufman (2018), Progress in Oceanography, which examines the temporal and spatial distributions of nutrients and particulate matter in the Ross Sea continental Shelf using cruise-based observations, and compares the resulting annual productivity estimates with previously reported satellite-based estimates. Specifically, these data represent distributions of nutrients, chlorophyll, particulate organic carbon, particulate organic nitrogen, and biogenic silica that were compiled from 42 cruises (from 1967 - 2016) to the Ross Sea continental shelf to generate a comprehensive climatological dataset for November, December, January, and February. This climatology provides a novel look at …

The Influence Of Juncus-Rhizosphere Dissolved Organic Matter On Coastal Plankton Communities, Brittany Zepernick, Robert Michael Mckay, George S. Bullerjahn, Jeffrey W. Krause, Behzad Mortazavi

Honors Projects

Many aquatic plants produce copious amounts of dissolved organic matter (DOM) which enters surrounding waters and potentially stimulates planktonic activity. In the northern Gulf of Mexico, Juncus roemarianus (i.e. black needlerush) is a dominant marsh grass species residing in coastal zones and barrier islands. The below-ground biomass i.e. rhizosphere, can be consistently submerged, serving as a potential source of DOM to the surrounding waters. The lability and possible stimulatory effect of J. roemarianus DOM was examined for three plankton communities collected within the discharge region of Mobile Bay and adjacent waters of Gulf Shores, Alabama (less affected by Mobile Bay). …

Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb

Student Scholar Symposium Abstracts and Posters

The oceanic productivity of the Indian Ocean and temperature anomalies prior to the Sumatra-Andaman earthquake (MW =9.3) and tsunami (December 26th 2004) were studied. Data was obtained via NASA’s Giovanni program to determine the effect on phytoplankton (primary producers) and temperature changes over the region of the earthquake. Seasonal trends were visible in the concentrations of chlorophyll a, coccolithophores, cyanobacteria, chlorophytes, diatoms and absorption coefficient, in addition to storm trends.

Ecohydraulic Investigation Of Diatoms In A Bedrock-Controlled Stream, Alex M. Rittle

Theses and Dissertations--Geography

Recent studies within the past decade or so have shown the importance of algae in geomorphic and hydrologic processes of lotic systems. However, the ecohydraulic role of algae in bedrock systems has largely been ignored. In addition, the utility of algae as indicators of channel dynamics have often been assumed by geomorphologists, but relatively few studies have examined this relationship. The purpose of this study was to determine whether algae, specifically diatoms, are useful indicators of channel geomorphological dynamics, and to examine if distinct habitats or biotopes typical in fluviokarst and bedrock systems provide unique habitat space for diatoms, and …

How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

Through the use of remote sensing, we are able to determine the approximate location of the garbage patch in the North Pacific Gyre. Though remote sensing does not penetrate the surface of the ocean, monthly satellite images can be analyzed to determine the rate of growth or rate of decrease of certain parameters, such as atmospheric gases, phytoplankton, and dissolved organic matter. Over the past decade, data from the Goddard Earth Sciences Data and Information Services Center (Giovanni program) has shown a significant increase in dissolved organic matter and chlorophyll a content in the area of the North Pacific Garbage …

Evidence Of Climate Variability And Tropical Cyclone Activity From Diatom Assemblage Dynamics In Coastal Southwest Florida, Emily R. Nodine

FIU Electronic Theses and Dissertations

Estuaries are dynamic on many spatial and temporal scales. Distinguishing effects of unpredictable events from cyclical patterns can be challenging but important to predict the influence of press and pulse drivers in the face of climate change. Diatom assemblages respond rapidly to changing environmental conditions and characterize change on multiple time scales. The goals of this research were to 1) characterize diatom assemblages in the Charlotte Harbor watershed, their relationships with water quality parameters, and how they change in response to climate; and 2) use assemblages in sediment cores to interpret past climate changes and tropical cyclone activity.

Diatom assemblages …

Rapid Fluctuations In Mid-Latitude Siliceous Plankton Production During The Middle Eocene Climatic Optimum (Odp Site 1051, Western North Atlantic), Jakub Witkowski, Steven M. Bohaty, Kirsty M. Edgar, David M. Harwood

ANDRILL Research and Publications

The Middle Eocene Climatic Optimum (MECO; ~ 40 million years ago [Ma]) is one of the most prominent transient global warming events in the Paleogene. Although the event is well documented in geochemical and isotopic proxy records at many locations, the marine biotic response to the MECO remains poorly constrained. We present new high-resolution, quantitative records of siliceous microplankton assemblages from the MECO interval of Ocean Drilling Program (ODP) Site 1051 in the subtropical western North Atlantic Ocean, which are interpreted in the context of published foraminiferal and bulk carbonate stable isotope (δ¹⁸O and δ¹³C) records. …

Diatom Proteomics Reveals Unique Acclimation Strategies To Mitigate Fe Limitation, Brook L. Nunn, Jessica F. Faux, Anna A. Hippman, Maria T. Maldonado, H. Rodger Harvey, David R. Goodlett, Philip W. Boyd, Robert F. Strzepek

OES Faculty Publications

Phytoplankton growth rates are limited by the supply of iron (Fe) in approximately one third of the open ocean, with major implications for carbon dioxide sequestration and carbon (C) biogeochemistry. To date, understanding how alteration of Fe supply changes phytoplankton physiology has focused on traditional metrics such as growth rate, elemental composition, and biophysical measurements such as photosynthetic competence (Fv/Fm). Researchers have subsequently employed transcriptomics to probe relationships between changes in Fe supply and phytoplankton physiology. Recently, studies have investigated longer-term (i.e. following acclimation) responses of phytoplankton to various Fe conditions. In the present study, the coastal diatom, Thalassiosira pseudonana, …

The Use Of Diatoms To Infer Environmental Change Of The Lower White River, Southeastern Arkansas, Ruchi Bhattacharya

Graduate Theses and Dissertations

This dissertation describes the limnology of the lower White River oxbow lakes in southeast Arkansas, inundated by the major 2008 spring flood. The flood water and sediment deposited in oxbow lakes were analyzed for water chemistry, sediment geochemistry and diatom assemblages and used as an analogue for past floods. The 2008 spring flood inundated and homogenized the entire floodplain; also represented by the predominantly planktonic diatom assemblage suggesting riverine input. Indicator species for eutrophication were also recorded consistent with the high nutrient content in the lakes. However, the variance in the surface diatom assemblage was best explained by the lake …

The Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: I. The Phytoplankton Community And Biogeochemical Response, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Y Zhang, G.R. Ditullio, P. Lee, Steven Wilhelm, J.M. Rowe, J. Sun, N. Nemcek, C. Gueguen, U. Passow, I. Benner, C. Brown, D.A. Hutchins

Steven Wilhelm

ABSTRACT: The North Atlantic spring bloom is one of the largest annual biological events in the ocean, and is characterized by dominance transitions from siliceous (diatoms) to calcareous (coccolithophores) algal groups. To study the effects of future global change on these phytoplankton and the biogeochemical cycles they mediate, a shipboard continuous culture experiment (Ecostat) was conducted in June 2005 during this transition period. Four treatments were examined: (1) 12°C and 390 ppm CO₂ (ambient control), (2) 12°C and 690 ppm CO₂ (high pCO₂), (3) 16°C and 390 ppm CO₂ (high temperature), and (4) 16°C and …

The Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: I. The Phytoplankton Community And Biogeochemical Response, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Y Zhang, G.R. Ditullio, P. Lee, Steven Wilhelm, J.M. Rowe, J. Sun, N. Nemcek, C. Gueguen, U. Passow, I. Benner, C. Brown, D.A. Hutchins

Microbiology Publications and Other Works

ABSTRACT: The North Atlantic spring bloom is one of the largest annual biological events in the ocean, and is characterized by dominance transitions from siliceous (diatoms) to calcareous (coccolithophores) algal groups. To study the effects of future global change on these phytoplankton and the biogeochemical cycles they mediate, a shipboard continuous culture experiment (Ecostat) was conducted in June 2005 during this transition period. Four treatments were examined: (1) 12°C and 390 ppm CO₂ (ambient control), (2) 12°C and 690 ppm CO₂ (high pCO₂), (3) 16°C and 390 ppm CO₂ (high temperature), and (4) 16°C and …

Light Environment And Seasonal Dynamics Of Microalgae In The Annual Sea Ice At Terra Nova Bay, Ross Sea, Antarctica, L. Lazzara, I. Nardello, C. Ermanni, O. Mangoni, V. Saggiomo

OES Faculty Publications

We investigated the physical conditions of the Spring pack ice environment at Terra Nova Bay to understand their influence on the structure and physiology of sympagic microalgae. Bio-optical methods were used to study the availability and spectral quality of solar radiation, both inside and underneath the ice cover. Pack ice thickness was around 2.5 m, with a temperature between -2 and -7°C. On average, only 1.4% of surface PAR penetrated to the bottom ice and less than 0.6% below platelet ice level. Surface UV-B radiation under the bottom ice was 0.2-0.4%. Biomass concentrations up to 2400 mg Chl a m- …

Austrochlamys Heardensis (Fleming, 1957) (Bivalvia: Pectinidae) From Central Kerguelen Plateau, Indian Ocean: Palaeontology And Possible Tectonic Significance, P. G. Quilty, C. V. Murray-Wallace, J. M. Whitehead

Faculty of Science - Papers (Archive)

Austrochlamys heardensis (Fleming) is recorded from a boulder of Late Pliocene (3.62–2.5 Ma) volcaniclastic sandstone dredged 70 km east-north-east of Heard Island, the third record of the species. The collection is much larger than the original described by Fleming and includes left valves which are described for the first time. The species is compared with A. anderssoni (Hennig) from Cockburn Island and ‘Chlamys’ mawsoni Fletcher from Îles Kerguelen. The source rock accumulated in fully marine, highly current-affected conditions. The collection is dominated by right valves, possibly because left valves are more susceptible to breakage and the effects of current winnowing. …

Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

The Rappahannock River is a major river system across north central Virginia prior to entering the Chesapeake Bay. In contrast, the Pamunkey River is smaller in size and joins the Mattoponi River to form the York River, which flows parallel to the Rappahannock before it also flows into Chesapeake Bay. A unique mixing area for both flora and environmental conditions exists in the tidal freshwater-oligohaline region of both rivers. This is a dynamic mixing section where freshwater and estuarine species are subject to the interaction of river flow and daily tidal rhythms. The phytoplankton composition in this region of the …

Holocene Sediment Records From The Continental Shelf Of Mac. Robertson Land, East Antarctica, Peter N. Sedwick, Peter T. Harris, Lisette G. Robertson, Gary M. Mcmurtry, Maximilian D. Cremer, Philip Robinson

OES Faculty Publications

Geochemical records are presented for five sediment cores from basins on the continental shelf of Mac. Robertson Land, East Antarctica. The cores contain 2-4 m thick sequences of hemipelagic, siliceous mud and ooze (SMO) deposited under seasonally open marine conditions. The inner and middle shelf SMO sequences are massive dark olive green material, whereas the outer shelf SMO sequences are dark olive material interspersed with light olive green layers similar to1-10 cm thick. The biogenic material is dominated by marine diatoms including Fragilariopsis curta, Fragilariopsis cylindrus, and Chaetoceros spp. in the dark-colored SMO and Corethron criophilum in the …

Nomenclatural Changes For Some Diatoms Found In Iowa, David B. Czarnecki

Journal of the Iowa Academy of Science: JIAS

Nomenclatural revisions for four diatom taxa found in Iowa, two of which are presently maintained in the Loras College Freshwater Diatom Culture Collection (FDCC), are necessary because of systematic interpretations of the Division Bacillariophyta. Achnanthidium hauckianum (Grun.) Czarnecki comb. nov. was originally assigned to the genus Achnanthes Bory. Three taxa were previously assigned to the morphologically diverse genus Navicula Bory. These are Cavinula weinzierlii (Schimanski) Czarnecki comb. nov., Craticula cuspidata var. major [(Meist.) Czarnecki comb. nov. and] Craticula halophila var. subcapitata (0str.) Czarnecki comb. nov.

Phytoplankton Relationships To Water Quality In Lake Drummond And Two Drainage Ditches, Christine G. Phillips, Harold G. Marshall

Biological Sciences Faculty Publications

A twelve-month phytoplankton study was conducted in Lake Drummond and Washington and Jericho Ditches from December 1988 to November 1989. Four dominant phytoplankton groups were identified at these sites. These were the Bacillariophyceae, Cyanophyceae, Cryptophyceae and an autotrophic picoplankton component. Over the past 20 years there has been a decrease in the mean pH levels of Lake Drummond and the replacement of one its former major components, the Chlorophyceae, by the Cyanophyceae. Based on water quality analysis results and species diversity indices, Lake Drummond is classified as in an early eutrophic stage of development.

An Interpretation Of Hustedt's Terms "Schattenlinie", "Perlenreihe" And "Hocker" Using Specimens Of The Cyclotella Radiosa-Complex, C. Distinguenda, Hust., And C. Cyclopuncta Nov. Sp., Hannelore Hakansson, John R. Carter

Journal of the Iowa Academy of Science: JIAS

With the help of light- and scanning electron micrographs HUSTEDT'S terms "Schattenlinie", "Perlenrcihe", and "Hocker" are explained using specimens in the Cydotella radiosa complex, and C. distinguenda HUST. The complicated history of C. operculata (AG.) KUTZ., published elsewhere, has shown that C. distinguenda HUST. is the correct name to be used for this taxon. In this connection the new nomenclatural combination C. distinguenda var. unipunctata nov. comb. is proposed.

Morphological differences are discussed and the possibility of different "unipunctata" species is shown. Distinct morphological features found indicate the necessiry to describe a new species: C. cyclopuncta nov. sp. rather than …

Diatoms (Bacillariophyceae) From The Excelsior Fen-Complex, Dickinson Co., Iowa, With The Description Of Two New Taxa, Charles W. Reimer

Journal of the Iowa Academy of Science: JIAS

This paper presents a summary list of the presently known diatom flora of the Excelsior Fen-complex and a description of two new taxa: Navicula incompta var. incurva Reim. var. nov. and Stauroneis bovbjergii Reim. sp. nov. Notes on some physico-chemical parameters of the habitat and on the ecology of the taxa are included.

An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel

Publications (WR)

Relic diatoms in sediments of the inner Las Vegas Bay, near the Las Vegas Wash sewage inflow, were examined in order to assess historic trophic conditions in this area of Lake Mead. Diatom sedimentation rates and ratios of Araphidineae/Centrales (A/C) diatom groups were determined from sediment cores collected in the old wash channel 1.5 km from the sewage inflow (station 2), in a small cove 1.5 km further downstream (station 3) and in an adjacent embayment off Gypsum Wash (station 4). Diatom sedimentation rates generally increased from the bottom to the top of each core, but pronounced minima existed at …