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Full-Text Articles in Climate

How Elevation Affects Epiphyte Distribution: An Analysis In Epiphyte Distribution Changes At Different Elevations And Tree Strata In Santa Lucia Cloud Forest Reserve, Ecuador, Nicole L. Melnick Oct 2022

How Elevation Affects Epiphyte Distribution: An Analysis In Epiphyte Distribution Changes At Different Elevations And Tree Strata In Santa Lucia Cloud Forest Reserve, Ecuador, Nicole L. Melnick

Independent Study Project (ISP) Collection

Cloud forests are unique ecosystems due to their tropical nature, high elevations, and extremely high presence of epiphytes that serve many important roles for the ecosystem’s biotic and abiotic components. As epiphytes can make up anywhere from one-quarter (Foster 2001) to a half (Gómez González et al. 2017) of all local plant species in cloud forests, it is essential to understand how their habitat distributions change with elevation and whether climate change will have a significant effect on that. This study used observational survey methods to record the amount of monocots (separately counted bromeliads and orchids), dicots, ferns, and percent …


Regenerative Agriculture Framework For Island Ecosystems Using São Miguel As A Case Study, Mya Hunter Oct 2022

Regenerative Agriculture Framework For Island Ecosystems Using São Miguel As A Case Study, Mya Hunter

Independent Study Project (ISP) Collection

Context: Regenerative agriculture is a farming approach that uses soil health as the entry point to contribute to multiple objectives, such as improved nutrient cycling and climate regulation. Farmers can apply different practices to reach these objectives. The objectives and practices, however, are not equally relevant or applicable for farming systems on island ecosystems and the local context.

Objectives: The main objective of this paper, therefore, is to find out how solutions towards regenerative agriculture can be identified and evaluated as such that they result in meaningful advice for farmers on island ecosystems in order to mitigate the …


Investigating Primary Succession Following The Retreat Of The Breiðamerkurjökull Glacier, Iceland, Ella Roelofs Oct 2022

Investigating Primary Succession Following The Retreat Of The Breiðamerkurjökull Glacier, Iceland, Ella Roelofs

Independent Study Project (ISP) Collection

The accelerating rates of glacier retreat around the world as a result of climate change make the study of primary succession in expanding forefields increasingly important. While this is a well studied topic in many parts of the world, little data exists specific to Iceland. This study investigated vegetation development along a chronosequence of eight time periods in the Breiðamerkurjökull outwash plain. Data was collected on percent vegetation cover, dominant species, the number of unique plant groups, and percent cover of five substrate types at 10 plots (0.55 x 0.55 m quadrats) per time period. Important findings include the fact …


Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening Oct 2022

Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening

Independent Study Project (ISP) Collection

As mangrove forests are destroyed by human factors across the earth, many crucial ecological processes that take place in these systems of trees are obstructed. One of the most important roles played by mangroves is their ability to sequester carbon in the sediment, as this storage of carbon helps diminish atmospheric warming. Many sediment microorganisms help in this process of carbon sequestration and play various other vital roles in mangrove ecosystems. Microorganisms in marine sediments can be used to assess the health of the surrounding environment. Past research has found significant differences in sediment microorganism composition, abundance, and diversity in …


Treatments Of Cyanobacteria On Mariculture Sponges In Jambiani, Tanzania, Sally Thornton-White Oct 2022

Treatments Of Cyanobacteria On Mariculture Sponges In Jambiani, Tanzania, Sally Thornton-White

Independent Study Project (ISP) Collection

Since 2009, Marine Cultures, an NGO, has explored sponge farming in Jambiani to develop secure and sustainable livelihoods for the community. While sponge farming provides economic opportunity for an industry that functions within ecological boundaries, it faces unique issues that threaten its success. As climate change increases global water temperatures, cyanobacteria are causing increased death rates among mariculture sponges. Mitigating these negative effects with sustainable and reliable solutions can help Marine Cultures grow their positive impact. Alternative methods for mitigating cyanobacteria growth were tested during three study phases. Phase 1 tested how sponge health and algae growth responds to being …


El Parque De La Papa Y El Centro Internacional De La Papa: Un Caso De Estudio De Una Colaboración Única Para La Conservación De Diversidad Biocultural, Molly Orr Oct 2022

El Parque De La Papa Y El Centro Internacional De La Papa: Un Caso De Estudio De Una Colaboración Única Para La Conservación De Diversidad Biocultural, Molly Orr

Independent Study Project (ISP) Collection

El Parque de la Papa, un territorio biocultural indígena en Cusco, Perú, es un sitio de conservación in situ de variedades de papas nativas apoyado por la ONG Asociación ANDES. En 2004, entró en un convenio con el Centro Internacional de la Papa (CIP) para la repatriación, restauración y seguimiento de las papas bajo el cual 410 variedades de papa fueron devueltas al Parque. El convenio ha formado la base para una relación continua entre CIP y el Parque; han desarrollado capacitaciones, investigaciones participativas e intercambios de conocimientos científicos y tradicionales. La colaboración entre CIP y el Parque es un …


Las Interacciones Entre La Migración Y El Sistema Alimentario Globalizado En Oaxaca, México, Abby Dryden Oct 2022

Las Interacciones Entre La Migración Y El Sistema Alimentario Globalizado En Oaxaca, México, Abby Dryden

Independent Study Project (ISP) Collection

En este artículo tiene como guía tres preguntas: 1. ¿Cómo interactúa el sistema alimentario globalizado con la migración interna en Oaxaca y entre Oaxaca y los Estados Unidos? 2. ¿Qué impacto el proceso de globalización tiene para el sistema alimentario y para las comunidades en Oaxaca? 3. ¿Cómo los temas de seguridad de comida y soberanía de alimentos están impactando Oaxaca? Esta investigación tiene lugar en Oaxaca, México porque estuve viviendo allí por tres meses y es un buen lugar para esta investigación en el contexto de la diversidad allí. Si bien es cierto que existe mucha información sobre el …


Climate Warming Amplifies The Frequency Of Fish Mass Mortality Events Across North Temperate Lakes, Simon P. Tye, Adam M. Siepielski, Andrew Bray, Andrew L. Rypel, Nicholas B.D. Phelps, Samuel B. Fey Aug 2022

Climate Warming Amplifies The Frequency Of Fish Mass Mortality Events Across North Temperate Lakes, Simon P. Tye, Adam M. Siepielski, Andrew Bray, Andrew L. Rypel, Nicholas B.D. Phelps, Samuel B. Fey

Biological Sciences Faculty Publications and Presentations

Recent increases of animal mass mortality events have coincided with substantial changes in global climate. Yet, tractable approaches that predict how climate change will accentuate occurrences of these ecological catastrophes remain nascent. We compiled one of the most comprehensive datasets of lentic fish mortality events, thermal tolerances of affected families, and 1.2 million air and water temperature profiles across 8891 north temperate lakes in North America. Temperature extremes within and across lakes were strongly associated with the three most frequent cause types (infectious agents, summerkills, winterkills). Thermal tolerances mediated the lethality of direct thermal stress, but mortalities of warm- and …


Spatio-Temporal Changes In Vegetation In The Last Two Decades (2001–2020) In The Beijing–Tianjin–Hebei Region, Yuan Zou, Wei Chen, Siliang Li, Tiejun Wang, Le Yu, Min Xu, Ramesh P. Singh, Cong-Qiang Liu Aug 2022

Spatio-Temporal Changes In Vegetation In The Last Two Decades (2001–2020) In The Beijing–Tianjin–Hebei Region, Yuan Zou, Wei Chen, Siliang Li, Tiejun Wang, Le Yu, Min Xu, Ramesh P. Singh, Cong-Qiang Liu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In terrestrial ecosystems, vegetation is sensitive to climate change and human activities. Its spatial-temporal changes also affect the ecological and social environment. In this paper, we considered the Beijing–Tianjin–Hebei region to study the spatio-temporal vegetation patterns. The detailed analysis of a moderate-resolution imaging spectroradiometer (MODIS) data were carried out through the Google Earth Engine (GEE) platform. Our results show a slow and tortuous upward trend in the average leaf area index (LAI) in the study region for the periods 2001–2020. Specifically, Beijing had the highest LAI value, with an average of 1.64 over twenty years, followed by Hebei (1.30) and …


Optimization Techniques For Soil Organic Carbon Prediction Using Mid-Infrared Spectroscopy, Minerva J. Dorantes Aug 2022

Optimization Techniques For Soil Organic Carbon Prediction Using Mid-Infrared Spectroscopy, Minerva J. Dorantes

Graduate Theses and Dissertations

Resource-efficient techniques for accurate soil carbon estimation are necessary to satisfy the increasing demand for spatiotemporal data. In the last thirty years, mid-infrared (MIR) soil spectroscopy has developed as an accurate, rapid, cost-effective, and non-destructive technique for soil organic carbon (SOC) analysis. In soil spectroscopy, a calibration model relates spectral data to a corresponding measured soil property and is subsequently used to predict this value from new spectral data. Various optimization techniques have been used to improve the statistical performance of calibrations; however, there is little consensus on the conditions that make these techniques effective. The objectives of this research …


Investigation Of Dead Ocean Quahogs (Arctica Islandica) Shells On The Mid-Atlantic Bight Continental Shelf, Alyssa Leclaire Aug 2022

Investigation Of Dead Ocean Quahogs (Arctica Islandica) Shells On The Mid-Atlantic Bight Continental Shelf, Alyssa Leclaire

Master's Theses

Ocean quahogs, Arctica islandica, are a long-lived, widely dispersed, biomass dominate in the Mid-Atlantic; therefore, quahog shells are valuable resources for studying climate change over time. Recently, dead ocean quahog shells were discovered south and inshore of the present biogeographic range of this animal. The presence of ocean quahog shells outside the current range is presumably a consequence of past regressions and transgressions of the Cold Pool, the bottom-trapped, cool body of water that allows boreal animals to live at lower latitudes. Dead ocean quahog shells were collected offshore of the DelMarVa Peninsula then radiocarbon-dated, evaluated for taphonomic condition, …


Prediction Of Cultivation Areas For The Commercial And An Early Flowering Wild Accession Of Salvia Hispanica L. In The United States, Mohammad Hassani, Thomas Piechota, Hagop S. Atamian Jul 2022

Prediction Of Cultivation Areas For The Commercial And An Early Flowering Wild Accession Of Salvia Hispanica L. In The United States, Mohammad Hassani, Thomas Piechota, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Salvia hispanica L., commonly known as chia, is a plant-based alternative to seafood and is rich in heart-healthy omega-3 fatty acid, protein, fiber, and antioxidants. In the Northern Hemisphere, chia flowering is triggered by the fall equinox (12-h light and dark, early October) and the seeds mature after approximately three months. Chia is sensitive to frost and end of season moisture which limits its cultivation to small areas in regions with temperate climate. The U.S. chia import has increased considerably over the years; however, chia is not widely cultivated in the United States. This study used the historical U.S. temperature …


Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg Jun 2022

Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg

Computer Engineering

This project examines the development of a smart boat which could serve as a possible marine research apparatus. The smart boat consists of a miniature vessel containing a low-cost microcontroller to live stream a camera feed, GPS telemetry, and compass data through its own WiFi access point. The smart boat also has the potential for autonomous navigation. My project captivated the interest of several members of California Polytechnic State University, San Luis Obispo’s (Cal Poly SLO) Marine Science Department faculty, who proposed a variety of fascinating and valuable smart boat applications.


Use Of Consumer Grade Small Unmanned Aerial Systems (Suas) For Mapping Storm Damage In Forested Environments, James Dewey Cox May 2022

Use Of Consumer Grade Small Unmanned Aerial Systems (Suas) For Mapping Storm Damage In Forested Environments, James Dewey Cox

Theses and Dissertations

Storm damages to forested environments pose significant challenges to landowners, land managers, and conservationists alike. Damage scope and scale assessments can be difficult, costly, and time consuming with conventional pedestrian survey techniques. Consumer grade sUAS technology offers an efficient, cost-effective way to accurately assess storm damage in small to moderate sized survey areas (less than 10 km²). Data were collected over a 0.195 km² area of damaged timber within the Kisatchie National Forest in Central Louisiana using a DJI Mavic 2 Pro drone. Collected imagery was processed into an orthomosaic using Agisoft Metashape Professional with a resulting ground sampling distance …


Maximization Of Fitness By Phenological And Phenotypic Plasticity In Range Expanding Rabbitfishes (Siganidae), Salvador Zarco-Perello, David Fairclough, Chris Dowling, Joey Dibattista, Rachel Austin, Thomas Wernberg, Brett Taylor May 2022

Maximization Of Fitness By Phenological And Phenotypic Plasticity In Range Expanding Rabbitfishes (Siganidae), Salvador Zarco-Perello, David Fairclough, Chris Dowling, Joey Dibattista, Rachel Austin, Thomas Wernberg, Brett Taylor

Fisheries Research Articles

  1. Global warming is modifying the phenology, life-history traits and biogeography of species around the world. Evidence of these effects have increased over recent decades; however, we still have a poor understanding of the possible outcomes of their interplay across global climatic gradients, hindering our ability to accurately predict the consequences of climate change in populations and ecosystems.
  2. We examined the effect that changes in biogeography can have on the life-history traits of two of the most successful range-extending fish species in the world: the tropical rabbitfishes Siganus fuscescens and Siganus rivulatus. Both species have established abundant populations at higher …


Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo Apr 2022

Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the dynamics of peatland methane (CH4) emissions and quantifying sources of uncertainty in estimating peatland CH4 emissions are critical for mitigating climate change. The relative contributions of CH4 emission pathways through ebullition, plant-mediated transport, and diffusion, together with their different transport rates and vulnerability to oxidation, determine the quantity of CH4 to be oxidized before leaving the soil. Notwithstanding their importance, the relative contributions of the emission pathways are highly uncertain. In particular, the ebullition process is more uncertain and can lead to large uncertainties in modeled CH4 emissions. To improve model simulations of CH4 emission and its pathways, …


Water: The Gift And The Curse: A Climate Change Preparedness Study On An Increased Rainfall Scenarios In The Yunguilla Cloud Forest, Ecuador, Emilia Dick Fiora Del Fabro Apr 2022

Water: The Gift And The Curse: A Climate Change Preparedness Study On An Increased Rainfall Scenarios In The Yunguilla Cloud Forest, Ecuador, Emilia Dick Fiora Del Fabro

Independent Study Project (ISP) Collection

The purpose of this project was to try and better understand the risks posed to the Yunguilla community in an increased rainfall climate change scenario. While climate modeling is not exact, many models do predict increased rain and storm intensity in this area (“Explainer…”, 2018). This project studies erosion risk, and the potential damage to crops through a series of experiments and mapping.

The first experiment used three hydration percentages 50, 75 and 100, to water two crop types, Fragaria and Caspium, and monitored plant health to see the water's effect. The hydraulic stress testing did not model an increased …


Assessing The Threat Of Coral Decline On Fish Diversity In Response To Temperature, Ryland Talmadge Apr 2022

Assessing The Threat Of Coral Decline On Fish Diversity In Response To Temperature, Ryland Talmadge

Independent Study Project (ISP) Collection

Misali, a PECCA-protected island off the east coast of Pemba, Tanzania, is considered to be a marine biodiversity hotspot with a protected Non-Extractive Zone (NEZ) and remaining Extractive Zone (EZ). Upon protection, the island’s fringe reefs faced severe coral bleaching during the 1998 bleaching event, estimated to kill up to 70% of corals. Since the event, several others have occurred in addition to restructuring the management plan in 2006 to expand the region to 1000km. While the damage from the most recent coral bleaching event in 2020 has yet to be surveyed, this study investigates the current reef health in …


Los Impactos Del Cambio Climático En Las Comunidades Aymaras En Putre, El Valle De Azapa Y Arica, Lindsey Kaufman Apr 2022

Los Impactos Del Cambio Climático En Las Comunidades Aymaras En Putre, El Valle De Azapa Y Arica, Lindsey Kaufman

Independent Study Project (ISP) Collection

Research Question: How is climate change affecting Aymara communities in Putre, the valley of Azapa, and Putre?

Objectives: To understand the effects of climate on communities by 1) describing which environmental problems exist and their impact on agriculture and ranching, 2) understanding the patterns of migration away from the ancestral land, 3) exploring the connections to the social determinants of health that exist with these change, and 4) analyzing the significance of these changes in the agriculture for the communities’ traditions and connection to the land.

Background: Aymara communities have historically inhabited agricultural and ranching lands in …


Aquatic Diversity In A Changing Tropical Andean Glacierized Catchment: Macroinvertebrates Reveal Possible Important Consequences To The Chimborazo Region As Glaciers Recede And The Climate Continues To Change, Tanner Thomas Apr 2022

Aquatic Diversity In A Changing Tropical Andean Glacierized Catchment: Macroinvertebrates Reveal Possible Important Consequences To The Chimborazo Region As Glaciers Recede And The Climate Continues To Change, Tanner Thomas

Independent Study Project (ISP) Collection

Tropical Andean glaciers are retreating rapidly, and their disappearance will have drastic consequences for the people and ecosystems that depend on them. While they have begun to receive the attention they deserve in scientific literature, much is still not known. Majority of these investigations have taken place on the Volcán Antisana, while other important glacierized systems, like the Volcán Chimborazo have received little attention. This investigation aimed to a) evaluate the possible effects of glacier loss and climate change on aquatic ecosystems by comparing glacial meltwater, non-glacial and mixed streams, and b) to evaluate the effects of pasture intensity on …


Commodity Prices, Climate And The High Plains Aquifer, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Silva, Karina A. Schoengold Mar 2022

Commodity Prices, Climate And The High Plains Aquifer, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Silva, Karina A. Schoengold

Cornhusker Economics

Crop prices and energy prices can affect the water level in an aquifer? Absolutely, yes, because over time, they affect the amount withdrawn for irrigation. Our recent research confirms that effect and provides estimates of the size of the effect on the High Plains Aquifer (HPA). The HPA underlies parts of eight states and 208 counties in the west-central United States (see Figure 1). This region produces more than 9% of US crop sales and relies on the aquifer for irrigation. These withdrawals for irrigation have contributed to a diminished stock of water in the aquifer that varies considerably across …


Empirically Derived Thermal Thresholds Of Four Coral Species Along The Red Sea Using A Portable And Standardized Experimental Approach, Nicolas R. Evensen, Christian R. Voolstra, Maoz Fine, Gabriela Perna, Carol Buitrago-López, Anny Cárdenas, Guilhem Banc-Prandi, Katherine Rowe, Daniel J. Barshis Mar 2022

Empirically Derived Thermal Thresholds Of Four Coral Species Along The Red Sea Using A Portable And Standardized Experimental Approach, Nicolas R. Evensen, Christian R. Voolstra, Maoz Fine, Gabriela Perna, Carol Buitrago-López, Anny Cárdenas, Guilhem Banc-Prandi, Katherine Rowe, Daniel J. Barshis

Biological Sciences Faculty Publications

Global warming is causing an unprecedented loss of species and habitats worldwide. This is particularly apparent for tropical coral reefs, with an increasing number of reefs experiencing mass bleaching and mortality on an annual basis. As such, there is a growing need for a standardized experimental approach to rapidly assess the thermal limits of corals and predict the survival of coral species across reefs and regions. Using a portable experimental system, the Coral Bleaching Automated Stress System (CBASS), we conducted standardized 18 h acute thermal stress assays to quantitively determine the upper thermal limits of four coral species across the …


Precipitation Is A Strong Predictor Of Airborne Ammonia Levels., Bridger Jorgensen, Casey Olson, Connor Snow Feb 2022

Precipitation Is A Strong Predictor Of Airborne Ammonia Levels., Bridger Jorgensen, Casey Olson, Connor Snow

Research on Capitol Hill

USU senior Connor has lived in the Uintah Basin all his life and studies kinesiology. Senior Casey, a Cache Valley native, studies climate science and works at the Utah Climate Center. Junior Bridger, also of Cache Valley, studies nutrition science. They led and funded this project through a student grant. Casey was alarmed by the ammonia data he was collecting at the Climate Center. “I immediately began to wonder how this issue would evolve over the coming decades.” The three teamed up to take a look at how Logan’s record-breaking amount of ammonia in our air is impacting those who …


Belowground Mechanism Reveals Climate Change Impacts On Invasive Clonal Plant Establishment, Surendra Bam, Jacqueline P. Ott, Jack L. Butler, Lan Xu Feb 2022

Belowground Mechanism Reveals Climate Change Impacts On Invasive Clonal Plant Establishment, Surendra Bam, Jacqueline P. Ott, Jack L. Butler, Lan Xu

Natural Resource Management Faculty Publications

Climate change and disturbance can alter invasion success of clonal plants by differentially affecting the clonal traits influencing their establishment as young plants. Clonal traits related to the vegetative reproduction of native Pascopyrum smithii and non-native Bromus inermis grass seedlings were evaluated under altered precipitation frequencies and a single grazing event. Pascopyrum smithii maintained similar vegetative reproduction under three simulated precipitation frequencies whereas B. inermis vegetative reproduction declined as precipitation became more intermittent. Vegetative reproduction of the non-native B. inermis was greater than the native P. smithii under all simulated precipitation frequencies except the most intermittent scenario. A single grazing …


Soil Resilience And Arbuscular Mycorrhizal Fungi: How Fungi Can Inform Climate Change Mitigation And Adaptation In Maya Milpa Management, Courtney Mathers Jan 2022

Soil Resilience And Arbuscular Mycorrhizal Fungi: How Fungi Can Inform Climate Change Mitigation And Adaptation In Maya Milpa Management, Courtney Mathers

Electronic Theses and Dissertations

In Mexico’s state of Yucatán, climate change impacts like prolonged and less predictable dry season length are manifesting as threats to agricultural production and food security. Nearly two thirds of Yucatán’s population is indigenous, many of whom live in rural communities that rely on rainfed subsistence agriculture (INEGI 2015). Ensuring sufficient food production in the face of climate change relies on the quality of agricultural soils. With both mismanagement of agricultural soils and climate change posing as threats to food production in Mexico, soil management practices that increase a soil quality should be identified and promoted. The primary objective of …


Technical Note: Novel Estimates Of The Leaf Relative Uptake Rate Of Carbonyl Sulfide From Optimality Theory, Georg Wohlfahrt, Albin Hammerle, Felix M. Spielmann, Florian Kitz, Chuixiang Yi Jan 2022

Technical Note: Novel Estimates Of The Leaf Relative Uptake Rate Of Carbonyl Sulfide From Optimality Theory, Georg Wohlfahrt, Albin Hammerle, Felix M. Spielmann, Florian Kitz, Chuixiang Yi

Publications and Research

In order to estimate the gross primary productivity (GPP) of terrestrial ecosystems from the canopy uptake of carbonyl sulfide (COS), the leaf relative uptake rate (LRU) of COS with respect to carbon dioxide needs to be known a priori. Currently, the variability of the LRU between plant species in different biomes of the world is poorly understood, making the choice of an appropriate LRU uncertain and hampering further progress towards developing COS as an alternative tracer of GPP. Here we propose a novel approach for estimating LRU based on plant optimality principles, validate it against in situ leaf gas exchange …


Coastal Upwelling Enhances Abundance Of A Symbiotic Diazotroph (Ucyn-A) And Its Haptophyte Host In The Arctic Ocean, Corday R. Selden, Sveinn V. Einarsson, Kate E. Lowry, Katherine E. Crider, Robert S. Pickart, Peigen Lin, Carin J. Ashjian, P. Dreux Chappell Jan 2022

Coastal Upwelling Enhances Abundance Of A Symbiotic Diazotroph (Ucyn-A) And Its Haptophyte Host In The Arctic Ocean, Corday R. Selden, Sveinn V. Einarsson, Kate E. Lowry, Katherine E. Crider, Robert S. Pickart, Peigen Lin, Carin J. Ashjian, P. Dreux Chappell

OES Faculty Publications

The apparently obligate symbiosis between the diazotroph Candidatus Atelocyanobacterium thalassa (UCYN-A) and its haptophyte host, Braarudosphaera bigelowii, has recently been found to fix dinitrogen (N2) in polar waters at rates (per cell) comparable to those observed in the tropical/subtropical oligotrophic ocean basins. This study presents the novel observation that this symbiosis increased in abundance during a wind-driven upwelling event along the Alaskan Beaufort shelfbreak. As upwelling relaxed, the relative abundance of B. bigelowii among eukaryotic phytoplankton increased most significantly in waters over the upper slope. As the host’s nitrogen demands are believed to be supplied primarily by UCYN-A, …


Photorespiration In Eelgrass (Zostera Marina L.): A Photoprotection Mechanism For Survival In A Co₂-Limited World, Billur Celebi-Ergin, Richard C. Zimmerman, Victoria J. Hill Jan 2022

Photorespiration In Eelgrass (Zostera Marina L.): A Photoprotection Mechanism For Survival In A Co₂-Limited World, Billur Celebi-Ergin, Richard C. Zimmerman, Victoria J. Hill

OES Faculty Publications

Photorespiration, commonly viewed as a loss in photosynthetic productivity of C3 plants, is expected to decline with increasing atmospheric CO2, even though photorespiration plays an important role in the oxidative stress responses. This study aimed to quantify the role of photorespiration and alternative photoprotection mechanisms in Zostera marina L. (eelgrass), a carbon-limited marine C3 plant, in response to ocean acidification. Plants were grown in controlled outdoor aquaria at different [CO2]aq ranging from ~55 (ambient) to ~2121 μM for 13 months and compared for differences in leaf photochemistry by simultaneous measurements of O2 flux and …


Simulated Response Of St. Joseph Bay, Florida, Seagrass Meadows And Their Belowground Carbon To Anthropogenic And Climate Impacts, Marie Cindy Lebrasse, Blake A. Schaeffer, Richard C. Zimmerman, Victoria J. Hill, Megan M. Coffer, Peter J. Whitman, Wilson B. Salls, David D. Graybill, Christopher L. Osburn Jan 2022

Simulated Response Of St. Joseph Bay, Florida, Seagrass Meadows And Their Belowground Carbon To Anthropogenic And Climate Impacts, Marie Cindy Lebrasse, Blake A. Schaeffer, Richard C. Zimmerman, Victoria J. Hill, Megan M. Coffer, Peter J. Whitman, Wilson B. Salls, David D. Graybill, Christopher L. Osburn

OES Faculty Publications

Seagrass meadows are degraded globally and continue to decline in areal extent due to human pressures and climate change. This study used the bio-optical model GrassLight to explore the impact of climate change and anthropogenic stressors on seagrass extent, leaf area index (LAI) and belowground organic carbon (BGC) in St. Joseph Bay, Florida, using water quality data and remotely-sensed sea surface temperature (SST) from 2002 to 2020. Model predictions were compared with satellite-derived measurements of seagrass extent and shoot density from the Landsat images for the same period. The GrassLight-derived area of potential seagrass habitat ranged from 36.2 km2 …


Defining The Realized Niche Of The Two Major Clades Of Trichodesmium: A Study On The West Florida Shelf, Kristina A. Confesor, Corday R. Selden, Kimberly E. Powell, Laura A. Donahue, Travis Mellett, Salvatore Caprara, Angela N. Knapp, Kristen N. Buck, P. Dreux Chappell Jan 2022

Defining The Realized Niche Of The Two Major Clades Of Trichodesmium: A Study On The West Florida Shelf, Kristina A. Confesor, Corday R. Selden, Kimberly E. Powell, Laura A. Donahue, Travis Mellett, Salvatore Caprara, Angela N. Knapp, Kristen N. Buck, P. Dreux Chappell

OES Faculty Publications

The cyanobacterium Trichodesmium plays an essential role supporting ocean productivity by relieving nitrogen limitation via dinitrogen (N-2) fixation. The two common Trichodesmium clades, T. erythraeum and T. thiebautii, are both observed in waters along the West Florida Shelf (WFS). We hypothesized that these taxa occupy distinct realized niches, where T. thiebautii is the more oceanic clade. Samples for DNA and water chemistry analyses were collected on three separate WFS expeditions (2015, 2018, and 2019) spanning multiple seasons; abundances of the single copy housekeeping gene rnpB from both clades were enumerated via quantitative PCR. We conducted a suite of statistical …