Physical Sciences and Mathematics Commons^™

An Analysis Of Tidal Mixing Front Dynamics And Frontal Biophysical Interaction In The Harpswell Sound Shelf Sea, Lemona Yingzhuo Niu

Honors Projects

Tidal Mixing Fronts (TMFs) are prominent hydrographic features of tidally energetic shallow shelf seas, representing the transition from mixed to stratified waters. These frontal boundaries often host enhanced phytoplankton primary productivity, as complete vertical mixing exhumes nutrients from depth to the light-lit surface. Existing observational programs for locating TMFs include infra-red satellite imagery of sea surface temperature (SST) and vertical profiling of temperature and density. However, challenges in observationally distinguishing mixed from mixing using only conservatively mixed hydrographic properties persist. A novel approach based on phytoplankton in-situ oxygen production response to light is proposed in this paper to distinguish stable …

The Southern Ocean Ecosystem Affects The Entire World, Eugene J. Murphy, Nadine M. Johnston, Eileen E. Hofmann, Richard A. Phillips, Jennifer E. Jackson, Andrew J. Constable

CCPO Publications

The Southern Ocean, which flows around the Antarctic continent, is home to vast numbers of unique and remarkable animals, including penguins, albatrosses, petrels, seals, and whales. The ocean bursts into life every spring, fueling a summer feeding and breeding frenzy. During the dark winter months, there is little food and life is very harsh. Human activities such as fishing and pollution are affecting this ecosystem, as is climate change. These ecosystem changes matter beyond the Southern Ocean! Ocean currents carry nutrients and organisms into and out of the Southern Ocean. Many marine mammals and seabirds swim or fly in and …

Microplankton Dynamics In The River-Dominated Mississippi Bight, Adam D. Boyette

Dissertations

The Mississippi Bight (MSB) is a river-dominated continental margin influenced by multiple large river systems, including the Mississippi River, Alabama and Tombigbee rivers via Mobile Bay, and numerous smaller rivers, creeks, and bayous. This is part of a biologically-rich ecosystem that supports the second largest fishery industry by volume in the United States. Despite our understanding of the linkages between primary production with higher trophic levels, there remains limited studies quantifying these trophic interactions in this system. Microplankton (µm) community dynamics and trophic connectivity between primary producers and heterotrophic protists represent a critical nexus influencing overall biological productivity in this …

The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and using …

Ecological Response Of Phytoplankton To The Oil Spills In The Oceans, Danling Tang, Jing Sun, Li Zhou, Sufen Wang, Ramesh P. Singh, Gang Pan

Mathematics, Physics, and Computer Science Faculty Articles and Research

Oil spills in oceans have substantial influence on marine ecosystems. This study investigates 21 oil spills in the world. Analyzing Chlorophyll-a (Chl-a) from Moderate Resolution Imaging Spectroradiomerer (MODIS) data after Penglai oil spills on 4 June 2011, found a bloom with peak value of Chl-a (13.66 mg m⁻³) spread over an area of 800 km² during 18–25 June 2011, and a pronounced increase in the monthly Chl-a concentration (6.40 mg m⁻³) on June 2012 in the Bohai Sea. Out of the 21 oil spills, 14 blooms were observed, while 11 …

Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

The continuing climate change is negatively impacting ecosystems, specifically oceans which are declining and food webs are being altered by the increase of greenhouse gases. The increase of the carbon dioxide and other greenhouse gases is increasing sea surface temperature of the world’s oceans. Certain organisms lower on the food chain like phytoplankton and zooplankton are directly affected by the warming which alters how they process nutrients and their productivity. The limited amount of these primary producers in the oceans and specifically the location they inhabit directly affects all the organisms above them on the food chain. Several marine animals …

Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a critical need for detailed surveys of lakes covering large spatial (>100 km²) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r²=0.85, p

Production Of Bioactive Secondary Metabolites By Florida Harmful Bloom Dinoflagellates Karenia Brevis And Pyrodinium Bahamense, Cheska Burleson

USF Tampa Graduate Theses and Dissertations

Despite the critical role algae serve as primary producers, increases or accumulation of certain algae may result in Harmful Algal Blooms (HABs). Algal toxins from these blooms contribute significantly to incidences of food borne illness, and evidence suggests HABs are expanding in frequency and distribution. Mitigation of these HABs without knowledge of the ecological purpose and biochemical regulation of their toxins is highly unlikely. The production, function, and potential of secondary metabolites produced by the dinoflagellates Karenia brevis and Pyrodinium bahamense, were investigated.

Brevetoxins were demonstrated by two different methods to localize within the cytosol of Karenia brevis. …