Physical Sciences and Mathematics Commons^™

Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards

Biological Sciences Faculty Publications

Mesophotic corals live at ~30-150 m depth and can sustain metabolic processes under light-limited conditions by enhancing autotrophy through specialized photoadaptations or increasing heterotrophic nutrient acquisition. These acclimatory processes are often species-specific, however mesophotic ecosystems are largely unexplored and acclimation limits for most species are unknown. This study examined mesophotic coral ecosystems using a remotely operated vehicle (Ashmore Reef, Western Australia at 40–75m depth) to investigate the trophic ecology of five species of scleractinian coral (from genera Leptoseris, Pachyseris, and Craterastrea) using stable isotope analyses (δ¹³C and δ¹⁵N) of host and symbiont tissues …

Stable Isotopes Used To Infer Trophic Position Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Gulf Of Mexico, United States, David C. Roche, Michael S. Cherkiss, Brian J. Smith, Derek A. Burkholder, Kristen M. Hart

Marine & Environmental Sciences Faculty Articles

Evaluating resource use patterns for imperiled species is critical for understanding what supports their populations. Here we established stable isotope (δ¹³C, δ¹⁵N) values for the endangered green sea turtle (Chelonia mydas) population found within the boundaries of Dry Tortugas National Park (DRTO), south Florida, USA. There is little gene flow between turtles sampled at DRTO and in other rookeries in Florida, underscoring the need to study this distinct population. Between 2008 and 2015 we collected multiple sample types (skin [homogenized epidermis/dermis], whole blood, red blood cells, plasma, carapace) from 151 unique green turtles, including …

Estimating The Denitrification Rate In Hood Canal Using Water Circulation, Spencer Johnson

WWU Honors College Senior Projects

Hood Canal is a long, fjordal estuarine inlet. Because of a sill near its mouth, Hood Canal experiences regular low oxygen in its bottom water; recently, dissolved oxygen has been even lower than usual, leading to fish kills and other ecosystem damage. Anthropogenic nutrients, particularly nitrogen, may be the cause, so it is important to quantify the components of the nitrogen cycle, like denitrification. To my knowledge, there is only one estimate of denitrification from Hood Canal in the literature. This study sought to supplement that data with an independent estimate of denitrification using water circulation along with N2 concentrations …

Size And Density Of Upside-Down Jellyfish, Cassiopea Sp., And Their Impact On Benthic Fluxes In A Caribbean Lagoon, Chester B. Zarnoch, Noshin Hossain, Erika Fusco, Mary Alldred, Timothy J. Hoellein, Sophia Perdikaris

School of Global Integrative Studies: Faculty Publications

Anthropogenic disturbances may be increasing jellyfish populations globally. Epibenthic jellyfish are ideal organisms for studying this phenomenon due to their sessile lifestyle, broad geographic distribution, and prevalence in near-shore coastal environments. There are few studies, however, that have documented epibenthic jellyfish abundance and measured their impact on ecological processes in tropical ecosystems. In this study, the density and size of the upside-down jellyfish (Cassiopea spp.) were measured in Codrington Lagoon, Barbuda. A sediment core incubation study, with and without Cassiopea, also was performed to determine their impact on benthic oxygen and nutrient fluxes. Densities of Cassiopea were 24–168 …

A Multidecade Experiment Shows That Fertilization By Salmon Carcasses Enhanced Tree Growth In The Riparian Zone, Thomas P. Quinn, Helfield M. James, Catherine S. Austin, Rachel A. Hovel, Andrew Godard Bunn

Environmental Sciences Faculty and Staff Publications

As they return to spawn and die in their natal streams, anadromous, semelparous fishes such as Pacific salmon import marine‐derived nutrients to otherwise nutrient‐poor freshwater and riparian ecosystems. Diverse organisms exploit this resource, and previous studies have indicated that riparian tree growth may be enhanced by such marine‐derived nutrients. However, these studies were largely inferential and did not account for all factors affecting tree growth. As an experimental test of the contribution of carcasses to tree growth, for 20 yr, we systematically deposited all sockeye salmon (Oncorhynchus nerka) carcasses (217,055 individual salmon) in the riparian zone on one …

Ulva Spp. Bloom Dynamics In A Hyper-Eutrophic Estuary: Jamaica Bay, New York, Annesia Lamb

Dissertations, Theses, and Capstone Projects

In this dissertation, I present three studies that further our understanding of macroalgae identity, growth, and proliferation. Eutrophication is prevalent in shallow coastal ecosystems world-wide. One of the ecosystem consequences is the development of a bloom forming green marine macroalgae, Ulva spp. Ulva can have negative effects such as Zostera spp. degradation, fish, and shellfish declines. I performed assessments of (1) identity of the bloom-forming Ulva and other macroalgae assemblage, (2) physical, chemical, and biological drivers of Ulva bloom growth and proliferation, and (3) optimal irradiance and temperature requirements for early growth stages in Ulva linza.

The first study …

Nutrient Dynamics And Ties To Environmental Conditions And Drivers In Central Puget Sound, Stephanie Jaeger, Ben Larson, Bob Kruger, Kimberle Stark

Salish Sea Ecosystem Conference

Real-time and near-continuous in-situ measurements can provide new insights into variability and patterns of a marine system that would otherwise be undetected by sampling at a lower temporal resolution. King County has a comprehensive long-term marine water quality monitoring program in the Central Basin of Puget Sound that currently includes: bi-monthly water column vertical profiles, discrete sampling, near-surface real-time moored sensors, and new quantitative phytoplankton and zooplankton components. These data can assist with identifying changes and linkages in biogeochemical and ecological processes as well as changes in climate patterns. Recently, new moored and profiling optical nitrate sensors were added to …

Nitrogen In Puget Sound: A Story Map, Sheelagh Mccarthy, Teizeen Mohamedali, Paula Cracknell

Salish Sea Ecosystem Conference

“Nitrogen in Puget Sound” is an ArcGIS Online Story Map developed by scientists at the Washington State Department of Ecology (Ecology). The Story Map is an interactive communication tool that uses a combination of maps, graphics, and text showcasing the state of the science and available data and resources used to understand nitrogen in Puget Sound. It was created to appeal to a broad audience, explaining nitrogen pollution and its effects at a basic level, as well as providing more detailed information for researchers and organizations interested in exploring available data and resources. The Story Map begins with an overview …

Watershed Assessment Modelling To Identify Critical Sources Of Pollution And Evaluate Effectiveness Of Conservation Management Practices, Nichole Embertson, Meagan Harris, Andrew Phay

Salish Sea Ecosystem Conference

Critical watershed assessments allow land managers to create strategic plans and prioritize funding and technical assistance when resources are limited. The Natural Resources Conservation Service (NRCS) National Water Quality Initiative (NWQI) provides a framework for watershed assessment to support long-term, strategic watershed planning and prioritize resources. The Tenmile Watershed in the Nooksack Basin in Whatcom County was selected as a pilot watershed for the NWQI assessment for Washington State in 2017. The primary objective of this assessment was to identify critical source areas (CSAs) within the watershed that were most susceptible to nutrient, sediment and bacteria export based on physical …

Assessing Phytoplankton Nutritional Status And Potential Impact Of Wet Deposition In Seasonally Oligotrophic Waters Of The Mid-Atlantic Bight, P. N. Sedwick, P. W. Bernhardt, M. R. Mulholland, R. G. Najjar, L. M. Blumen, B. M. Sohst, C. Sookhdeo, Brittany Widner

OES Faculty Publications

To assess phytoplankton nutritional status in seasonally oligotrophic waters of the southern Mid-Atlantic Bight, and the potential for rain to stimulate primary production in this region during summer, shipboard bioassay experiments were performed using natural seawater and phytoplankton collected north and south of the Gulf Stream. Bioassay treatments comprised iron, nitrate, iron + nitrate, iron + nitrate + phosphate, and rainwater. Phytoplankton growth was inferred from changes in chlorophyll a, inorganic nitrogen, and carbon-13 uptake, relative to unamended control treatments. Results indicated the greatest growth stimulation by iron + nitrate + phosphate, intermediate growth stimulation by rainwater, modest growth …

Blooms Of Dinoflagellate Mixotrophs In A Lower Chesapeake Bay Tributary: Carbon And Nitrogen Uptake Over Diurnal, Seasonal, And Interannual Timescales, Margaret R. Mulholland, Ryan Morse, Todd Egerton, Peter W. Bernhardt, K. C. Filippino

OES Faculty Publications

A multi-year study was conducted in the eutrophic Lafayette River, a sub-tributary of the lower Chesapeake Bay during which uptake of inorganic and organic nitrogen (N) and C compounds was measured during multiple seasons and years when different dinoflagellate species were dominant. Seasonal dinoflagellate blooms included a variety of mixotrophic dinoflagellates including Heterocapsa triquetra in the late winter, Prorocentrum minimum in the spring, Akashiwo sanguinea in the early summer, and Scrippsiella trochoidea and Cochlodinium polykrikoides in late summer and fall. Results showed that no single N source fueled algal growth, rather rates of N and C uptake varied on seasonal …

An Examination Of El Niño's And Agricultural Runoff's Effect On Harmful Algal Blooms And California Sea Lion (Zalophus Californianus) Health In Monterey Bay, Nadine Lafeber

Scripps Senior Theses

An increase in marine mammal stranding and die-off events has been observed along the California coast. The exact cause to explain for these recent events is unknown, but El Niño and harmful algal blooms are established sources for temporary decreases in marine mammal health. To determine whether El Niño could be causing and amplifying harmful algal blooms, particularly in Monterey Bay where they occur frequently, data was analyzed from the Marine Mammal Center in Sausalito, California. Data analysis focused on California sea lions (Zalophus californianus), because they have the largest data set and are directly affected by harmful …

Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker

2014 Student Theses

Over three million people call Long Island their home. With access to beautiful landscapes, world-renowned beaches, and proximity to New York City, it is no wonder that so many proudly call this geographic stretch of glacial till their home. However, throughout the years our actions do not necessarily reflect this affection we have to our home. Years of sprawl and human infestation across the island have resulted in widespread environmental degradation. Specifically, the water we drink and the beaches we enjoy have become endangered. I plan on studying the urban ecology of how intensified population growth led to the eutrophication …

Phytoplankton And Nutrient Dynamics In A Tidally Dominated Eutrophic Estuary: Daily Variability And Controls On Bloom Formation, Ryan E. Morse, Margaret R. Mulholland, Todd A. Egerton, Harold G. Marshall

OES Faculty Publications

To better understand nutrient dynamics and factors that promote the initiation of algal blooms, the Lafayette River, a tidal subestuary of Chesapeake Bay that experiences seasonal algal blooms, was sampled daily for a period of 54 d in the fall of 2005. Three phytoplankton blooms (chl a concentrations exceeding twice the average of monthly measurements from 2000 to 2009) occurred during this period: a mixed bloom of Akashiwo sanguinea and Gymnodinium sp., a monospecific Skeletonema costatum bloom, and a monospecific Gymnodinium sp. bloom. Over the sampling period, nutrient concentrations increased following precipitation events and were elevated between bloom periods but …

Fertilizer And Stormwater Runoff Outreach Program In Newcastle, Nh, David Anderson

PREP Reports & Publications

The New Hampshire Coastal Protection Partnership (NH Coast) implemented a year long pilot public education and outreach program in the Town of New Castle aimed at reducing nitrogen pollution from lawn fertilizers and promoting rain gardens as a solution to storm water runoff and nonpoint source pollution. A total of 77 landowners representing 138 acres of land pledged to either not use lawn fertilizers or use only low phosphorus, slow release nitrogen brands. The program also resulted in the installation of New Castle’s first demonstration rain garden.

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO₂ levels. Rates of N₂ and CO₂ fixation and growth increased in step with increasing partial pressure of CO₂ (pCO₂), but only under Fe- replete conditions. N₂) and carbon fixation rates at 75 Pa CO₂ were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO_{2 …}

Biochemical Composition Of Particles And Dissolved Organic Matter Slong An Estuarine Gradient: Sources And Implications For Dom Reactivity, Antonio Mannino, H. Rodger Harvey

OES Faculty Publications

The chemical composition of high molecular weight dissolved organic matter (DOM) and particulate organic matter (POM) was examined along the salinity gradient of the Delaware Estuary. DOM was collected and fractionated by tangential-flow ultrafiltration into 1-30 kDa (HDOM; high molecular weight) and 30 kDa to 0.2 μm (VHDOM; very high molecular weight) and compared to particles collected in parallel. Polysaccharides comprised 12-43% of particulate organic carbon (POC), 30-56% of VHDOM carbon, and 7.5-19% of HDOM carbon. Hydrolyzable amino acids comprised 17-38% of POC, 5.4-12% of VHDOM carbon, and 1.5-4.2% of HDOM carbon. Only 7-43% of dissolved organic nitrogen in VHDOM …