Life Sciences Commons^™

Editorial: Unraveling Mechanisms Underlying Annual Plankton Blooms In The North Atlantic And Their Implications For Biogenic Aerosol Properties And Cloud Formation, Michael Behrenfeld, Sarah D. Brooks, Peter Gaube, Kristina D.A. Mojica

Faculty Publications

No abstract provided.

Phytoplankton Community Response To Changing Environmental Conditions Across Two Central California Sites, Nicholas Soares

Biological Sciences

Understanding the role that changing environmental conditions play in altering phytoplankton abundance and community composition, and in turn ecosystem structure and function, will be increasingly important for the sustainable use and management of ocean resources in a changing climate. Characterizing change in nearshore ecosystems requires long-term studies with a broad spatial extent, with most studies sacrificing spatial extent for temporal duration. However, phytoplankton and ecosystem response can vary substantially over small spatial scales due to local oceanographic forcing and anthropogenic influence, making the application of long-term data from one site to another in the same geographic vicinity potentially challenging. In …

Construction Of Dichotomous Taxonomic Keys For San Francisco Bay Planktonic Diatoms, Ria Angelica Laxa

Undergraduate Honors Theses

Planktonic diatoms exhibit high biodiversity in marine systems and make a significant contribution to water column primary productivity. This makes research on planktonic diatoms particularly important in measuring the health of coastal marine ecosystems. At the University of San Francisco (USF), undergraduate research has been conducted since September 2015 to study planktonic diatoms in San Francisco Bay. A previous study by Keith (2018), Planktonic Diatom Species Succession in San Francisco Bay, documented changes in species diversity over time, observing seasonal patterns in species richness as well as the effect of environmental factors such as salinity, temperature, and rainfall on species …

Alexandrium In The Arctic: Are Harmful Algae Spreading As The Arctic Warms?, Sveinn Einarsson, Kate Lowry, Robert Pickart, Karin Ashjian, P. Dreux Chappell

College of Sciences Posters

Alexandrium tamerense is a well-studied dinoflagellate known for its ability to produce the neurotoxin that causes paralytic shellfish poisoning. Until 1970 Alexandrium tamerense was only found in Europe, North America, and Japan but has been increasingly found all over the globe. Alexandrium is characteristically found in temperate and subtropical regions and as the Arctic warms, there is considerable concern that it may be expanding into the Arctic. We found Alexandrium tamerense during a research expedition to the Alaskan Beaufort Sea shelf to study upwelling. Upwelling events are known to support seasonal blooms of phytoplankton, which are important primary producers at …

Fortnightly Effects Of Urea Additions On Cyanobacteria In A Stormwater Detention Pond, Halley Carruthers

Theses and Dissertations

Increased urban and suburban population growth along the South Carolina (SC) coast has led to a rise in impervious surfaces, altering the course of stormwater runoff events. The construction of stormwater detention ponds (SDPs) is one of the many ways to best mitigate the flow of this water. In their function as natural pollutant traps, SDPs often contain increased levels of nutrients (nitrogen, N and phosphorus, P), which can lead to eutrophication. Under these high eutrophic conditions, primary production is overstimulated, and the formation of phytoplankton blooms, including harmful algal blooms (HABs) can occur. In recent decades, the forms of …

Developing A Method To Track Marine Snow Aggregation Through Individual Collisions Using Stereoscopic Imaging, Riley Henning

Theses

The aggregation of individual phytoplankton into marine snow allows particles to sink more quickly, thus resulting in the transport of particulate organic carbon from surface waters to the deep ocean. Aggregate formation has previously been measured in experiments indirectly by quantifying how particle size or particle concentration changes over time. Here, I present my thesis in which I applied high-resolution imaging to quantify aggregate formation using two different methodologies.

We conducted experiments to investigate aggregate formation using stereoscopic imaging, tracking individual particles directly in a 3D volume. Phytoplankton cultures were rolled in cylindrical tanks and imaged by two cameras illuminated …

Bioactive Trace Metals And Their Isotopes As Paleoproductivity Proxies: An Assessment Using Geotraces-Era Data, T. J. Horner, S. H. Little, T. W. Conway, J. R. Farmer, Jennifer E. Hertzberg, D. J. Janssen, A.J.M. Lough, J.L. Mckay, A. Tessin, S.J.G. Galer, S. L. Jaccard, F. Lacan, A. Paytan, K. Wuttig, Geotraces-Pages Biological Productivity Working Group Members

OES Faculty Publications

Phytoplankton productivity and export sequester climatically significant quantities of atmospheric carbon dioxide as particulate organic carbon through a suite of processes termed the biological pump. Constraining how the biological pump operated in the past is important for understanding past atmospheric carbon dioxide concentrations and Earth's climate history. However, reconstructing the history of the biological pump requires proxies. Due to their intimate association with biological processes, several bioactive trace metals and their isotopes are potential proxies for past phytoplankton productivity, including iron, zinc, copper, cadmium, molybdenum, barium, nickel, chromium, and silver. Here, we review the oceanic distributions, driving processes, and depositional …