C-MORE Scholars’ Projects: Fall 2011–Spring 2012

Photo of C-MORE Scolars.

The Fall 2011–Spring 2012 C-MORE Scholars. Front row (L-R): Vy Luu, Ashley Bulseco, Sunny Kao, Monika Frazier, La'Toya James. Back Row (L-R): Jacobson Kibby, Jonathan Chandrasakaran, Lani Johnson, Christina Johnson, Bryan Chinaka, Paul Bump. (Click on the image to see a larger version.)

Trainees

April Goodson
Marine Science Senior, UH Hilo

“Quantification and classification of fouling microorganisms on plastic marine debris”
Mentor: Hank Carson

The project will involve quantification and classification of fouling microorganisms on plastic fragments retrieved from sixteen locations around the Great Pacific Garbage patch. The project will use SEM technology to count various bacteria, diatoms and other microorganisms through transects. Classification of organisms will be attempted using guides and reference from experts in the field. Statistical analysis will correlate their abundance with characteristics of the fragments, type of plastic and the location the fragment was found. The outcome of this project will be to describe the community that colonizes plastic, examine the variability of that community in space, and perhaps speculate on the ecosystem effects of providing durable habitat for that community in the north pacific gyre ecosystem.

Lani Johnson
Marine Biology Senior, UH Mānoa

“Microbial ecology of IODP Expedition 327 rock samples”
Mentors: Mike Rappé and Sean Jungbluth

The seafloor is one of the least studied habitats on Earth. It is important to understand the ecology of the microbial community at the seafloor to understand biogeochemical cycling and its relevance to global climate change. Water, sediment, and rock samples were taken from a seamount called Grizzly Bare, a location hundreds of miles off the coast of Washington State, about 52 km SSW of the Juan de Fuca Ridge, and roughly 1.5 miles below the sea surface. The goal of the project this semester is to analyze the microbial ecology of 12 water, 12 sediment, and 8 basement rock samples from Grizzly Bare using microscopy and nucleic acid extraction.

Kahoali‘i Keahi
Hawaiian Language Junior, UH Mānoa

“Biogeochemical Research in He‘eia Fishpond, O‘ahu”
Mentors: Kathleen Ruttenberg and Danielle Hull

This project is a continuation and further development of biogeochemical research in He‘eia Fishpond that was initiated in 2007 by the Ruttenberg lab with funding from NOAA-Sea Grant. We are monitoring various physical and biogeochemical aspects of He‘eia Fishpond, a native Hawaiian Fishpond that is under the care of the non-profit Paepae O He‘eia, a group which is working to restore the fishpond to its pre-anthropogenic-impact, pristine state. Our research is aimed at understanding nutrient cycling in the fishpond, and we are investigating the ways in which elevated sediment and nutrient inputs may be impacting pond ecology, in particular the possibility that an altered biogeochemistry may be selecting for invasive over indigenous algae and higher order animals. The trainee will participate in both continuous and discrete sampling efforts.

Jacobson Kibby
Marine Science Junior, UH Hilo

“Mapping Korsae Coastal Sites for Marine Plant Surveys”
Mentor: Karla McDermid

The most recent published coastal inventory for the island of Kosrae, Federated States of Micronesia, was in 1989. A new inventory is in progress by the Korsae Island Resource Management Authority. Accurate, up-to-date natural resource inventories are critical for making management decisions, and taking actions to preserve high biodiversity coastal areas. Coastal resource inventories often over-look or under-estimate marine plant populations. Marine plants, including seagrasses and seaweeds, create shelter and nursery habitat for fish and invertebrates, provide food for turtles and other marine herbivores, stabilize nearshore substrata, and are potential sources of beneficial products for humans. The goal of the project this semester is to review published and unpublished information on Kosrae marine plant resources, including distribution, abundance and species composition, identify and map priority sites for surveying, and plan sampling procedures for these sites.

John Lee
Biology Senior, UH Mānoa

”Kāne‘ohe Bay Copepod Project“
Mentors: Michelle Jungbluth and Erica Goetze

As an abundant and diverse component of the marine plankton, copepods are a critical link within the coastal food web. To study how copepod populations respond to environmental changes such as drought or heavy rainfall, it is necessary to be able to follow survival of a single generation of the population over time. However, in subtropical embayments such as in Kāne‘ohe Bay, Hawai‘i, coastal plankton populations reproduce year-round making it impossible to follow a single generation when all species are present in all life stages. Since juveniles cannot be identified visually to species, differential development times of the species make it an even greater challenge to tease apart survival. Molecular methods offer a promising way of identification of species, as well as quantifying how many there are. This scholar’s project will be developing and optimizing sequence specific DNA primers for two Kaneohe Bay cyclopoid copepod species, Oithona simplex and Oithona attenuata, with the goal of using these primers in future studies looking how they are affected by environmental disturbance.

Interns

Ashley Bulseco
Marine Science Senior, UH Hilo

“Surface Water Metabolism Potential and Microbial Population Dynamics at Kaloko-Honokōhau and Kiholo Bay, Hawai'i”
Mentor: Tracy Wiegner

Submarine groundwater discharge is a significant source of fresh and nutrient rich waters on the Kona coast of Hawai‘i Island. Porous basalt prevents surface water runoff, so nutrients such as nitrogen (N) and phosphorus (P) vital for coral reefs and productivity are provided by groundwater. The purpose of this study is to gain a better understanding of the effects of groundwater influx at two sites: Kaloko-Honokōhau fishpond and Kiholo Bay lagoon. These areas are different in that Kaloko is surrounded by high anthropogenic activity, and Kiholo Bay is relatively undeveloped and prone to the invasive Kiawe tree (Prosopis pallida). Over the course of 9 months, I will measure surface water metabolism potential to quantify the relationship between primary production and respiration, and will use flow cytometry to map the basic microbial assemblage present in areas affected by groundwater input. In addition, I intend to monitor chlorophyll levels, alkalinity, and nutrients along these sites over the course of a wet and dry season. It is hypothesized that Kaloko-Honokōhau fishpond will have a positive metabolism, and will act a net sink for atmospheric CO2 due to nutrient input responses. By understanding the characteristics of the groundwater at these nearshore sites along with their functional chemical and biological responses, we may be able to better manage and predict the impact excess nutrient fluxes have on our coastal ocean.

Paul Bump
Marine Biology Junior, UH Mānoa

“Understanding mechanisms of toxin production via transcriptome analysis of ciguatera-causing Gambierdiscus toxicus
Mentor: Henry Trapido-Rosenthal

The proposed work will use the Illumina platform and microarrays to probe the transcriptome of Gambierdiscus toxicus, a dinoflagellate that grows in Hawaiian coastal waters. Because the transcriptome of an organism reflects the genes that are actively being expressed at any given time, the proposed work, by elucidating levels of messenger RNA expression in the target organisms, is expected to provide valuable insights into the mechanisms responsible for toxin production, responses to stress and/or subsequent inactivation of pathogenic induction. Knowledge of the mechanisms associated with gambiertoxin production will enhance understanding of the relationship between environmental conditions and outbreaks of ciguatera fish poisoning (CFP). This will lead to more informed risk management and ultimately to the reduction of CFP. Such understanding is vital to advancing the field of risk management with respect to recreational water use and seafood consumption beyond reliance on empirical correlations and towards policies that are based on a mechanistic understanding of the threats these organisms pose to human health.

Jonathan Chandrasakaran
Marine Science Senior, UH Hilo

“Temporal and spatial analyses of microbial (Clostridium perfringens) and chemical indicators of sewage in
Hilo Bay, Hawai‘i.”

Mentor: Tracy Wiegner

Clostridium perfringens, an anaerobic, spore-forming bacterium that can be found in the intestinal tract of humans and sometimes in tropical soil, is a reliable indicator of sewage pollution and sewage tracer in coastal Hawaiian waters. Since waters contaminated with human feces are a greater risk to human health because they are more likely to contain human-specific enteric pathogens, it is imperative to distinguish sources of sewage to avoid the harming of human health. Hilo Bay was chosen to be the location for this project because it is estimated that a high percentage of urban Hilo is not connected to the sewer lines. To determine sewage "hotspots" where samples will be, an optical brightener probe is used to measure the relative of optical brightener, a common ingredient in many brands of detergents, in the water. The goal of this project is to determine the source(s) of sewage pollution by comparing the measured relative abundance of optical brightener and water turbidity to the abundance of C. perfringens.

Bryan Chinaka
GES Junior, UH Mānoa

“Mineral Carbon Sequestration using a Synthetic Olivine”
Mentor: Gregory Ravizza

Stabilizing atmospheric greenhouse gases has become one of the greatest challenges of mankind in the 21st century. The increasing rate of greenhouse gas emissions, in particular carbon dioxide emissions, is having a significant impact on the global greenhouse effect, and potentially causing dramatic climate changes according to numerous global-scale climate models. The goal of my project is to measure the amount of heat produced by olivine carbonation, the reaction of carbon dioxide with olivine to from magnesite and quartz, and to quantify the reaction rate over a range of temperatures and pressures. These measurements are important because they have significant implications for determining whether or not mineral carbonation can be an economically viable approach to long-term carbon sequestration.

Christina N. Johnson
GES Junior, UH Mānoa

“Biogeochemical and Molecular Analysis of pCO2-enriched Marine Diazotroph Assemblages in the Oligotrophic North Pacific Ocean”
Mentor: Matthew Church and Daniela Böttjer

With atmospheric CO2 levels projected to nearly triple by the year 2150, surface-layer ocean acidification could drastically alter the microbial communities responsible for “fixing” atmospheric nitrogen into biologically available forms in the oligotrophic (nutrient-poor) ocean. Through perturbation experiments, we will analyze the response of naturally occurring diazotrophic communities to increased pCO2 in the oligotrophic North Pacific Ocean. In particular, I will perform DNA extractions, as well as qPCR and RT-qPCR analysis of experimentally perturbed diazotrophs, quantify autotrophic biomass through chlorophyll-a fluorometry, and determine silicic acid concentrations by spectrophotometry. My goal is to gain exposure to, and become proficient with, analytical methods used to shed light on the microbial underpinnings of the ocean’s biogeochemical cycles.

Sunny Kao
Zoology, UH Mānoa

“The effects of ocean acidification on biofilm bacterial populations”
Mentor: Michael Hadfield

In aquatic ecosystems, bacteria are found primarily as an integrated part of adherent structured communities call biofilms. Biofilms are composed of many different microorganisms that are protected by a self-secreting matrix, the extracellular polymeric substances (EPS). With global climate change occurring at such a rapid rate, the natural biofilm community may also begin to shift (change). The continued heavy carbon-dioxide emissions are causing ocean pH levels to decrease, signaling increasing acidity in the oceans. While previous studies have focused primarily on calcifying organisms (i.e., corals), because of the direct effect the increasing acidity has on the formation of calcium carbonate, my current study examines how declining pH levels affect bacterial communities. My goal is to determine how the increasing ocean acidity changes the overall population structure of the bacterial biofilm community.

Vy Luu
Geophysics Sophomore, KCC

“Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling (FOODBANCS2)”
Mentor: Craig Smith

The Antarctic Peninsula region exhibits one of the largest warming trends in the world. Climate warming in this region is reducing the duration of winter sea-ice cover, altering both the pelagic ecosystem and pelagic-benthic coupling. A 3-year study along a latitudinal climate gradient on the Antarctic Peninsula has been conducted to explore the potential impacts of climate change (e.g.,reduction in sea-ice duration) on Antarctic shelf ecosystems. In this project, I will analyze two 5-month long, time-lapse photographic series of seafloor communities collected on the continenetal shelf near Smith Island (62.5°S) and in Marguerite Bay (68.5°S). These photographic time series of the seabed run from July 2009 (austral winter) to December 2009 (austral summer) and will be used to examine the feeding rates and mobility patterns of benthic deposit feeders along this climatic gradient to elucidate the potential response of this major trophic group to climatic warming.

C-MORE scholars program photo

Fellows

Monika Frazier
Marine Science Senior (graduated), UH Hilo

“Identification of diazotrophs associated with Montipora capitata among three sites on Hawai'i island”
Mentor: Misaki Takabayashi

Nitrogen is an essential nutrient to living organisms, constituting nucleic acids and proteins among other roles. The majority of nitrogen in the world is in the form of dinitrogen (N2), which is a form of nitrogen that is not biologically available to organisms. Diazotrophs are a diverse group of bacteria and archaea that are able to convert this abundant form of unavailable nitrogen to a form that can be used for processes such as photosynthesis. Nitrogenase is the enzyme produced by these organisms that allows them to convert, or fix nitrogen. Using molecular techniques, the DNA that codes for a subunit of the nitrogenase gene can be sequenced and used to identify the types of diazotrophs present in an environmental sample. In this study, I am comparing diazotrophs found in Montipora capitata tissue at three sites (Leleiwi, Pōhue and Waiōpae) on Hawai’i island. Coral reefs are characterized by high primary productivity, yet are found in low-nutrient waters. Photosynthesis occurring in coral tissue accounts for the majority of energy used for coral growth and reproduction, so understanding nutrient cycling within this system is an alluring topic.

La’Toya James
Biology Senior, UH Mānoa

“Pathogenicity of Vibrio parahaemolyticus in the Ala Wai Canal, Hawai‘i”
Mentor: Grieg Steward

Vibrio parahaemolyticus is an abundant bacteria found in most coastal waters of the world. This bacterium is naturally found inhabiting brackish waters. Some strains of V. parahaemolyticus have been found to be pathogenic to humans. Introduction of the species into humans may be through ingestion of under cooked or raw shellfish as well as through open cuts and wounds. Investigation of the temporal, spatial, and seasonal changes in abundance of this species is essential in efforts to predict severity of human infection and risks that are posed by the species in coastal waters. The goal of the project this semester is to enumerate total V. Parahaemolyticus within the Ala Wai Canal and Harbor. We also plan to enumerate those strains that carry virulence-associated genes.

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