Fall 2017 Ocean Sciences Seminar

Fall 2017 Seminars

A-340  Earth & Marine Sciences Building
Fridays, 10:40 - 11:45 a.m. (unless otherwise noted)

Seminar Coordinator: Carl Lamborg

For disability-related accommodations: call (831) 459-4730 or email rrobison@ucsc.edu

    September 29 - Welcome Party to Follow

  • Joel Blum, Professor, University of Michigan

    Mercury isotope studies in San Francisco Bay and its watershed

    This seminar will introduce the three types of mercury isotope fractionation and use examples from San Francisco Bay and surroundings to illustrate the use of mercury isotopes to trace contaminant sources and constrain biogeochemical processes.

  • October 6

  • Kim Null, Research Affiliate, Moss Landing Marine Lab

    Groundwater Discharge to the Western Antarctic Coastal Ocean

    Submarine groundwater discharge measurements have been limited along the Antarctic coast, although groundwater is becoming recognized as an important process in the Antarctic. Our study suggests that a large portion of the melting glacier may be infiltrating into the bedrock and being discharged to coastal waters along the western Antarctic Peninsula. Meltwater infiltrating as groundwater at glacier termini is an important solute delivery mechanism to the nearshore environment that can influence biological productivity. More importantly, quantifying this meltwater pathway may be worthy of attention when predicting future impacts of climate change on glacier retreat of tidewater glaciers.

  • October 13

  • Kakani Katija, Principal Engineer, Monterey Bay Aquarium Research Institute

    New technology enables the study of biomechanics, functional morphology, and ecology of giant larvaceans in the deep sea.

    The ocean’s midwaters is one of the least explored places on our planet, and is home to a wide array of little- known marine organisms that include giant larvaceans. Larvaceans build elaborate mucus structures (or houses) to filter food, and little is known about their structure and function. To address this need, we developed a laser-based instrument called DeepPIV, which can be deployed by remotely operated vehicles rated to 4000 m. Using DeepPIV, we are able to measure giant larvacean filtration rates to elucidate how these mucus structures function and contribute to carbon flux in the ocean.

  • October 20

  • Phillip Cleves, Postdoc, Stanford University, Pringle Lab

    Using the small anemone Aiptasia to understand the genetic basis of coral-Dinoflagellate symbiosis

    The endosymbiotic partnership between corals and dinoflagellate algae (genus Symbiodinium) is essential to the energetic requirements of coral-reef ecosystems. However, coral reefs are in danger due to elevated ocean temperatures and other stresses that lead to the breakdown of this symbiosis and consequent coral "bleaching". Despite its importance, the molecular basis of how corals establish and maintain a healthy symbiosis is poorly understood, in part because of the lack of the ability to functionally test candidate genes in corals and related symbiotic cnidarians. In this talk, I will discuss our work to identify genes involved in symbiosis and bleaching through transcriptomic analyses in the small anemone Aiptasia, a laboratory model for cnidarian symbiosis. I will also report our progress in establishing functional genetic tools in Aiptasia and corals.

  • October 27

  • Yuan Shen, Postdoc Researcher, University of California, Santa Cruz

    Molecular exploration of bioavailable dissolved organic matter across aquatic ecosystems

    Dissolved organic matter (DOM) in aquatic systems is a large reservoir of reduced carbon that is largely resistant to biodegradation. A small fraction of DOM is bioavailable on relatively short timescales, supporting microbial food webs and driving major elemental cycles. Bioavailable DOM is commonly determined using bioassay experiments which are labor intensive and limited in spatial and temporal coverage. In this talk, I will describe the development of amino acids-based molecular indicators that are applied to a wide range of systems to reflect ecosystem productivity in the polar oceans, locate biological hotspots in a subtropical ocean margin, and to trace transport of bioavailable DOM from surface to ground waters.

  • November 3

  • Mara Orescanin, Assistant Professor, Naval Postgraduate School

    Observations of intermittent breaching at the Carmel River, CA

    Ephemeral rivers provide unpredictable transport from back lagoons to the coastal ocean critical to biological processes such as larval transport, and understanding the relative role of discharge, tides, and waves is critical to understanding the expected area of influence.  The Carmel River, in Carmel, CA, is well-known to seasonally breach, though the duration and timing of each breach is difficult to predict.  Observations of seven distinct breaches from December 2016 through January 2017 indicate that while river discharge is low, the combined effect of waves and tides is sufficient to reduce flow through the breach, allowing sediment to accumulate at the mouth and close off the river.  

  • November 10

  • No Seminar - Holiday

  • November 17

  • Alyson Santoro, Assistant Professor, UC Santa Barbara

    Thaumarchaea in the Marine Nitrogen Cycle

    Marine thaumarchaea are small but mighty microbes involved in the first step of nitrification, an important process in the marine nitrogen cycle. Despite having one of the smallest genomes of any free-living microbe, they are thought to be the primary agents of ammonia oxidation in the ocean, and responsible for a large fraction of the ocean source of the greenhouse gas nitrous oxide. I will discuss recent field data from our laboratory about the role of marine particles as a source of nitrogen for nitrification, and new data quantifying the role of urea as an alternate source of ammonium. I will further discuss results from controlled laboratory experiments showing how gene expression in marine thaumarchaea is vastly different from typical model microorganisms, and why these differences have implications for how we study nitrification and nitrifiers in the wild.

  • November 24

  • NO SEMINAR - Holiday

  • December 1

  • Borja Reguero, Assistant Researcher, UC Santa Cruz

    The Economic Value of Coral Reefs in Flood Risk Reduction: A National Assessment for the U.S.A.

    The degradation of coastal habitats, particularly coral reefs, raises risks by exposing communities to increased flooding hazards. The protective services of these natural defenses are not assessed in rigorous, economic terms, and therefore often not considered in decision-making. A new methodology combines social, economic, ecological, and engineering tools to provide a high-resolution mapping and quantitative economic valuation of the coastal protection benefits of coral reefs for all states and territories with coral reefs. The results identify how and where coral reefs provide the most flood reduction benefits to people and assets to inform reef conservation and management priorities. The resulting high-resolution mapping (10m) can help to inform coastal resilience and develop innovative financing to support restoration of coral reefs in the U.S.A.


  • December 8

  • Meg Sedlak, Senior Program Manager, San Francisco Estuary Institute

    Monitoring for Chemicals of Emerging Concern in San Francisco Bay

    The Regional Monitoring Program (RMP) is an innovative collaboration among the San Francisco Estuary Institute, the Regional Water Quality Control Board, and the regulated discharger community to monitor contaminants in the Bay. The RMP provides water quality regulators and stakeholders with the information they need to manage the Bay for future generations to enjoy. Started in 1992, the RMP has expanded it's analyte list from a traditional suite of legacy contaminants such as mercury and PCBs to emerging contaminants such flame retardants, stain repellants, and microplastics. This talk will highlight the results of a few of our emerging contaminant studies.