Monday, April 22, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"Reconciling Theory to Predict Microbial Responses to Ocean Warming"
Suzana Gonçalves Leles, Ph.D.
University of Southern California
BIO: I am fascinated about the diverse lifestyles of marine microbes. I aim to understand how microbes respond to their environment as well as how they interact to influence the entire ecosystem. When doing that, I study their short-term and long-term responses to environmental changes to better predict microbial dynamics under future climate scenarios. I am also very curious about how we can combine models and data to answer various scientific questions. By combining theory, mathematical models and empirical data, I scale processes at the cellular level to ecosystems. I investigate molecular tradeoffs defined by acclimation and adaptation and apply this knowledge at larger scales to predict microbial biogeography and their impact in the ocean carbon cycle. In this talk, I will reconcile theory to predict microbial responses to warming and resource limitation. I will show how we can gain new insights by integrating theory, lessons from trait ecology, and a proteome model to empirical data from experimental evolution studies and ‘omics approaches.
Seminar summary: Microbes play a major role in the ocean carbon cycle. Yet, the mechanisms underlying their responses to climate change both in the short- and long- term are not well understood. In this talk, I will reconcile theory to reveal new insight into how phytoplankton might respond to warming stress and resource limitation. By combining mechanistic modeling, experimental evolution, and ‘omics datasets, we reveal the mechanisms behind why phytoplankton become smaller due to increases in temperature in the short-term, and how they might defy current trends and evolve larger cell sizes due to warming through evolutionary adaptation. When faced with both warm-stress and resource limitation, the metabolic choices of phytoplankton are more limited. Contrary to previous theory, we find that their temperature optima might increase under resource limitation. This response depends ultimately on their ability to effectively decrease their cell size. I will discuss this result in light of warm- and cold- adapted species, highlighting the implications to microbial biogeography. The fine-scale metabolic responses discussed here can be applied to constrain phytoplankton dynamics in large-scale ocean models. By linking ‘omics to models, my research hopes to contribute to unfold how phytoplankton might impact ecosystem processes in future climate scenarios.
Monday, April 8, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"Environmental Change Impact on Reef-Building Bivalves - Where Are We Going?"
Luca Telesca, Ph.D.
Lamont-Doherty Earth Observatory of Columbia University.
BIO: A Postdoctoral Research Scientist at the Lamont-Doherty Earth Observatory of Columbia University with broad interests in marine invertebrate biology, evolution, and climate change. My research focuses on habitat-forming species, especially marine bivalves, and the links between biomineralization and environmental conditions. I use a combination of field, materials science, and modelling methods to study natural responses in marine populations and ecosystems over space and time.
Seminar summary: As global climate change accelerates, accurate predictions of biological responses to environmental and human-caused disturbances are critical if we are to prevent likely damage to the biosphere. However, current predictions of organismal responses to change stem mainly from controlled experimental studies but lack assessments of mechanisms underlying biotic variations in natural systems. This is especially true for calcifying, reef-building marine species that have both high climate sensitivity and play key ecological roles for healthy ecosystem functioning. In this seminar, I will describe i) the role of salinity gradients in shaping unexpected spatial patterns of shell biomineralization and biomechanics in restored populations of a key ecosystem engineer, the eastern oyster Crassostrea virginica in the Hudson River Estuary (NY, USA), and ii) a novel field mesocosm to continuously monitor and evaluate temporal responses in oyster respiration, feeding and water filtration rate under multiple interacting environmental stressors in estuarine habitats. These works highlights the need for novel cross-disciplinary approaches, linking laboratory and field observations, to better predict how natural populations and their ecosystem services will cope with rapidly changing climates, which directly contribute to preservation and long-term sustainable use of healthy ocean ecosystems.
Monday, April 1, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"Life In the Mud: Interactions Between Infauna and Their Sediment Environments"
Kelly M. Dorgan, Ph.D.
Associate Professor, Marine Sciences, University of South Alabama and Senior Marine Scientist II, Dauphin Island Sea Lab.
BIO: Dr. Kelly M. Dorgan is a Senior Marine Scientist II at the Dauphin Island Sea Lab and an Associate Professor of Marine Sciences at University of South Alabama. Before joining the DISL faculty in 2013, Dr. Dorgan completed her Ph.D. in Oceanography from the University of Maine and was trained as a postdoctoral researcher in Integrative Biology at University of California, Berkeley, and in Marine Biology at the Scripps Institution of Oceanography, University of California, San Diego. Her research focuses on animal-sediment interactions, and she applies engineering tools to ecological questions. She has received several prestigious early-career awards, including the NSF Graduate Research Fellowship, the NDSEG Fellowship, the Association for the Sciences of Limnology and Oceanography (ASLO) Raymond L. Lindeman Award for the outstanding paper in aquatic science by a young scientist (2007), the Carl Gans Award “to an outstanding young investigator for distinguished contributions to the field of comparative biomechanics” from the Society for Integrative and Comparative Biology Division of Comparative Biomechanics. She has a strong funding record, including an NSF CAREER award, an ONR Young Investigator Award, and the National Academy of Sciences Gulf Research Program Early Career Research Fellowship. She has 46 peer-reviewed publications in journals including Nature and Proceedings of the Royal Society B. She developed and runs a mentoring program for undergraduates, and has published educational materials in Frontiers for Young Minds and the Oceanography Classroom section of Oceanography.
Seminar summary: Muddy sediments are inhabited by diverse communities of animals that burrow, construct and irrigate tubes, ingest and egest sediments, and produce hard structures such as shells and exoskeletons. These infaunal animals mix sediments through bioturbation and modify the physical properties of sediments. Understanding the mechanisms by which animals modify sediments and sediments influence animal behaviors provides insight into ecosystem engineering by these abundant and ecologically important communities. The effects of biological processes on sediments is also important in applications including seafloor stability, acoustic mapping and characterization of the seafloor, and biogeochemical cycling.
Thursday, March 28, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"How Human Activities and Climate Change Threaten Coastal Ecosystems, and What to Do About It?"
Guilherme N. Corte, Ph.D.
Assistant Professor, Biology, College of Science and Mathematics, University of the Virgin Islands.
BIO: Guilherme Corte holds a PhD in Ecology from the State University of Campinas (Brazil, 2016) and is currently a Professor of Biology in the College of Science and Mathematics at the University of the Virgin Islands, United States Virgin Islands. As a marine ecologist, he has worked on the coasts of North and South America, the Caribbean, and Australia. Guilherme has studied several marine habitats such as mangroves, rocky shores, open ocean, and sandy beaches. His research focuses on the interface between ecological science and the management of biological resources, and seeks to provide fundamental knowledge to preserve, manage, and enhance natural resources and ecosystems.
Seminar summary: Coastal ecosystems support rich biodiversity, provide essential ecosystem services, and contribute significantly to regional and global economies. Yet, their functioning is under increasing risk due to expanding human development and climate-related stressors. In this talk, I will present research I have conducted in Australia, Brazil, and the Caribbean investigating how human activities and climate change affect coastal biodiversity and ecosystem functioning. I will also demonstrate how we can use scientific evidence to improve the management and conservation of coastal ecosystems, and discuss future research to better understand and safeguard the coastal ecosystems of the Gulf of Mexico and beyond.
Wednesday, March 20, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"Larval Bivalve Development in Changing Oceans"
Wei Xu, Ph.D.
Associate Professor, Department of Marine Biology, Texas A&M University-Corpus Christi.
BIO: Dr. Wei Xu is an Associate Professor in Marine Biology at the Texas A&M University – Corpus Christi. Dr. Xu has broad research interests from marine mollusk development to environmental health. Using a collaborative and multidisciplinary approach, Dr. Xu’s group is dedicated to understanding the impacts of environmental change on marine organisms and humans with a focus on One Health of the Gulf of Mexico. To date, Dr. Xu’s group has published over 70 peer-reviewed scientific articles and has been involved in the development of four patents. His lab receives funding support from the NSF, NIH, DoD, Bureau of Safety and Environmental Enforcement, Cancer Prevention and Research Institute of Texas, and other state funding agencies and foundations. Dr. Xu received the NSF CAREER Award in 2021.
Seminar summary: Bivalves can be found in both marine and freshwater environments and play essential roles in various ecosystems. Although adult bivalves can employ rapid acclimation mechanisms to adapt to highly dynamic and stressful environments due to their lack of mobility, the early life history stages of bivalves, including embryos and larvae, are vulnerable to environmental stressors. We are particularly interested in understanding the environmental impacts on the critical developmental stages, shell formation and larval settlement, of marine bivalve species. Through an NSF-supported project, we established several in vitro and in vivo models, and research methods to investigate the molecular mechanisms of larval bivalve response to changing environments. With those animal models and platforms from this project, we expanded our study to the settlement stage of larval bivalves. The goal is to understand the influence of environmental changes on larval recruitment and settlement of bivalves mediated by the marine biofilms. The findings of these research projects help us generate reliable references for the aquaculture and restoration of shellfishes. They also provide a genetic base for the selective breeding of aquaculture bivalve species. Interestingly, the results from the shell formation study suggested the biomineralization of shell development and bone generation in vertebrates are mediated by similar regulatory pathways. This allows us to link our studies on marine bivalves to human health at the nexus of human, animal, and environmental health in the future.
Monday, March 18, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"How Do Reef-Forming Species Sustain Their Important Ecological Structures in a Changing Ocean?"
Keisha Bahr, Ph.D.
Assistant Professor, Department of Life Sciences, Texas A&M University-Corpus Christi.
BIO: Dr. Keisha Bahr is an Assistant Professor in the Department of Life Sciences at Texas A&M University-Corpus Christi (TAMU-CC). Before joining TAMU-CC, she was a Postdoctoral Scholar at the Hawaiʻi Institute of Marine Biology and completed her Ph.D. at the University of Hawaiʻi at Mānoa. As a marine ecologist, Keisha’s research interests are broad but focus on understanding how organisms react and adapt to natural and anthropogenic environmental stress. She seeks to reveal insights into ecosystem health and resilience and future patterns of biological diversity while providing practical solutions to managers, policymakers, and communities.
Monday, March 4, 9:00 am, In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
“Making the Unexpected Expected and Predictable: Microbial Diversity and Dynamics of Biogeochemical Cycles in a Changing Environment”
Xin Sun, Ph.D.
Postdoctoral Fellow, Biosphere Sciences & Engineering, Carnegie Science, Palo Alto, CA.
Thursday, February 29, 9:00 a.m., In-person & Zoom
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"Exploring Microbial Activities From Marshes to the Open Ocean"
Marshall Bowles, Ph.D.
Assistant Professor, Tulane School of Science and Engineering, LUMCON, Chauvin, LA.
Seminar summary: In this seminar we will explore microbial processes and activities from salt marshes to the open ocean. For salt marshes we will begin by reviewing basics of microbial metabolisms then explore the varying and unique environmental conditions in these ecosystems that lead to different microbial processes. In particular we will examine methane fluxes and microbe-plant interactions in the rhizosphere. Isotopic values of methane and dissolved inorganic carbon from marshes will be discussed along with measures of microbial abundance, potential metabolisms and identities. The primary goal of this work is to decipher the controlling factors for methane emissions from salt marsh sediment. We will then venture to the coastal ocean (Gulf of Mexico) and discuss sediment sulfate reduction and methane oxidation rates from this highly productive shelf environment. The spring 2023 cruise results indicate that prior to hypoxic conditions the iron cycle – iron reduction is a dominant dissimilatory process. The last portion of the talk will be devoted to a globally intensive modeling effort, wherein we examined net primary productivity (NPP) rates over the last ~21 years. The El Niño event of 2023, coupled to the marine heatwave, resulted in a drastic reduction in NPP, with equatorial/subtropical regions of the Atlantic and Pacific oceans leading the drop. The talk will conclude with an eye towards future research emphasis (e.g. cold seeps and deep subsurface) and on-going research that is well suited to the Gulf coast environment.
Monday, February 26, 9:00 a.m., In-person & Zoom.
UT Marine Science Institute, Patton Center, Auditorium
(Faculty Candidate Seminar)
"The Changing Coast - A Carbonate Chemistry Perspective"
Xinping Hu, Ph.D.
Professor, Chemistry, Department of Physical and Environmental Sciences, Harte Research Institute for Gulf of Mexico Studies, Texas A&M University-Corpus Christi.
BIO: Dr. Hu is a Professor of Chemistry at the Department of Physical and Environmental Sciences, Texas A&M University-Corpus Christi (TAMU-CC). He is also the Endowed Chair for Ecosystem Science and Modeling (an inherited title) at the Harte Research Institute for Gulf of Mexico Studies. Dr. Hu graduated from Peking University in China in 1997 with a bachelor’s degree in chemistry. After that, he spent a few years unsuccessfully pursuing marine drugs. However, after realizing the work would only involve boiling seaweeds of various kinds and taking the extracts to feed mice in order to look for random, unknown, medicinal effects, he gave up this direction and started pursing oceanography at Old Dominion University in Norfolk, Virginia. After he got his PhD in 2007, he worked at the University of Georgia, mostly as a postdoc, then briefly as a research scientist, before joining TAMU-CC in 2012. Dr. Hu’s research is carbon focused, from solid carbonate to gaseous CO2, and everything in between. His research has taken him to the Bahamas Bank, most of the US Gulf and east coasts, including 600 meters under the sea in a submarine, and a commercial facility where he worked on corals in the middle of a cornfield near Columbus Ohio. Dr. Hu was an NSF CAREER awardee (2017-2023), and he has served as a Scientific Steering Committee member for the U.S. Carbon and Biogeochemistry Program (US-OCB) in 2021-2023. He is now serving as an associate editor for both AGU’s Global Biogeochemical Cycles and EGU’s Ocean Science.
Seminar summary: Coastal and marine environments worldwide are undergoing significant transformations, including shifts in the hydrological cycle, eutrophication, ocean acidification, and warming. Located in the subtropical northwestern Gulf of Mexico, the estuaries, which span across a narrow latitudinal range yet experience a large freshwater inflow gradient, as well as the coastal ocean, have exhibited notable changes in their carbonate systems. This presentation will first discuss the dynamics of a crucial carbonate system parameters – total alkalinity – and its response to hydrological changes in the estuarine environment, which in turn affects sediment redox chemistry. The findings, however, suggest a swing from an observed overconsumption of alkalinity, after accounting for calcification, to an alkalinity surplus relative to the production of mineral acids, hence the question remains and needs further exploration. The latter part of the talk will address the apparent strong decadal acidification in the northwestern Gulf of Mexico, based on a comparison of two extensive oceanic surveys. Further examination suggests that these snapshots do not represent a trend (fortunately). Nevertheless, a gradual subsurface acidification is evident, as indicated by a “shoaling” of the saturation horizon. This change is driven by both the invasion of anthropogenic CO2 and water column respiration, with the latter significantly modulated by the terrestrial input of nutrients.
Seminar tabs are listed in the order of upcoming dates, followed by past seminars (most recent first).
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