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Full-Text Articles in Physical Sciences and Mathematics

Bioconversion Of Industrial Hemp Biomass For Bioethanol Production: A Review, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Kraig Roozeboom, Donghai Wang Dec 2020

Bioconversion Of Industrial Hemp Biomass For Bioethanol Production: A Review, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Kraig Roozeboom, Donghai Wang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Industrial hemp (Cannabis sativa L.) with robust drought-resistant features has excellent agronomic and pharmaceutical characteristics. As the federal prohibition on hemp cultivation was lifted, its valorization in various aspects is highly required. This review aims to summarize the potential of hemp biomass for bioethanol production. Chemical compositions of hemp biomass were evaluated as compared with those of corn fiber, corn stover, and sorghum bagasse. Several representative pretreatment technologies used for hemp biomass were summarized in terms of sugar recoveries, lignin removal, and sugar and ethanol yields. This review presents numerous technical barriers attributed to insufficient fermentable sugar and ethanol …


Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira Nov 2020

Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

South Texas is located in a subtropical semiarid climate, and due to high temperature and irregular precipitation, farmers opt to leave their fields fallow during the summer months jeopardizing overall soil health. We evaluated whether sweet potato (Ipomoea batatas) cultivation coupled with drip irrigation could restore soil biological activities compared with bare fallow. Additionally, because sweet potatoes have high demand of soil nutrients, especially potassium (K), we evaluated the nutrient supply of locally sourced soil amendments. Sweet potato was cultivated during summer 2018 in McAllen, Texas, under control (no fertilizer), NPK (synthetic fertilizer), RC (yard-waste compost), and AC (compost produced …


Characterization Of Pathogen Airborne Inoculum Density By Information Theoretic Analysis Of Spore Trap Time Series Data, Robin A. Choudhury, Neil Mcroberts Nov 2020

Characterization Of Pathogen Airborne Inoculum Density By Information Theoretic Analysis Of Spore Trap Time Series Data, Robin A. Choudhury, Neil Mcroberts

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

In a previous study, air sampling using vortex air samplers combined with species-specific amplification of pathogen DNA was carried out over two years in four or five locations in the Salinas Valley of California. The resulting time series data for the abundance of pathogen DNA trapped per day displayed complex dynamics with features of both deterministic (chaotic) and stochastic uncertainty. Methods of nonlinear time series analysis developed for the reconstruction of low dimensional attractors provided new insights into the complexity of pathogen abundance data. In particular, the analyses suggested that the length of time series data that it is practical …


Host Density Dependence And Environmental Factors Affecting Laurel Wilt Disease Incidence, Robin A. Choudhury, H. L. Er, M. Hughes, J. A. Smith, G. E. Pruett, J. Konkol, R. C. Ploetz, J. J. Marois, K. A. Marois, A. H. C. Van Bruggen Nov 2020

Host Density Dependence And Environmental Factors Affecting Laurel Wilt Disease Incidence, Robin A. Choudhury, H. L. Er, M. Hughes, J. A. Smith, G. E. Pruett, J. Konkol, R. C. Ploetz, J. J. Marois, K. A. Marois, A. H. C. Van Bruggen

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Host size, density, and distribution, in addition to climate, can affect the likelihood a pathogen will invade and saturate landscapes. Laurel wilt, caused by the vector‐borne pathogen Raffaelea lauricola, has devastated populations of native Lauraceae in the Southeastern US, and continues to spread. We surveyed 87 plots in six coastal islands in South Carolina, Georgia, and North Florida, and one inland site (Archbold Biological Station) in South Florida for laurel wilt‐affected and non‐affected individual plants belonging to the genus Persea. The coastal island sites were surveyed once in 2008 or 2009, and the inland site was surveyed eight …


Marine Wild-Capture Fisheries After Nuclear War, Kim J. N. Scherrer, Cheryl S. Harrison, Ryan F. Heneghan, Eric Galbraith, Charles G. Bardeen, Joshua Coupe, Jonas Jägermeyr, Nicole S. Lovenduski, August Luna, Alan Robock, Jessica Stevens, Samantha Stevenson, Owen B. Toon, Lili Xia Nov 2020

Marine Wild-Capture Fisheries After Nuclear War, Kim J. N. Scherrer, Cheryl S. Harrison, Ryan F. Heneghan, Eric Galbraith, Charles G. Bardeen, Joshua Coupe, Jonas Jägermeyr, Nicole S. Lovenduski, August Luna, Alan Robock, Jessica Stevens, Samantha Stevenson, Owen B. Toon, Lili Xia

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Nuclear war, beyond its devastating direct impacts, is expected to cause global climatic perturbations through injections of soot into the upper atmosphere. Reduced temperature and sunlight could drive unprecedented reductions in agricultural production, endangering global food security. However, the effects of nuclear war on marine wild-capture fisheries, which significantly contribute to the global animal protein and micronutrient supply, remain unexplored. We simulate the climatic effects of six war scenarios on fish biomass and catch globally, using a state-of-the-art Earth system model and global process-based fisheries model. We also simulate how either rapidly increased fish demand (driven by food shortages) or …


Brown Spot In Table Grape Redglobe Controlled In Study With Sulfur Dioxide And Temperature Treatments, Cassandra A. Young, Robin A. Choudhury, Carlos H. Crisosto, W. Douglas Gubler Oct 2020

Brown Spot In Table Grape Redglobe Controlled In Study With Sulfur Dioxide And Temperature Treatments, Cassandra A. Young, Robin A. Choudhury, Carlos H. Crisosto, W. Douglas Gubler

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Brown spot is a postharvest disease of grapes caused by Cladosporium species in the San Joaquin Valley of California. It spreads during cold storage and transport, resulting in severe economic losses to late table grape cultivars, which are grown mainly for export to countries such as China and Mexico. We examined the effect of temperature and sulfur dioxide (SO2) treatments on fungal growth and infection of Redglobe berries by three Cladosporium species: Cladosporium ramotenellum, C. cladosporioides and C. limoniforme. Redglobe is especially popular for export. Fungal colonies growing on potato dextrose agar in petri plates stored at −2°C grew slower …


Deep Sea Isopods From The Western Mediterranean: Distribution And Habitat, Joan E. Cartes, Diego F. Figueroa Oct 2020

Deep Sea Isopods From The Western Mediterranean: Distribution And Habitat, Joan E. Cartes, Diego F. Figueroa

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Isopods are a highly diversified group of deep-sea fauna, with a wide variety of shapes which must reflect a similar great variety of adaptations to the deep environments. The deep Mediterranean, however, has a low diversity of isopods related to its oligotrophy, the thermal stability of deep-water masses (∼12.8 °C below 150 - 200 m) and rather homogeneous geomorphology. The main factor defining isopod habitats in the Balearic Basin is insularity vs mainland influence. Desmosomatidae and Ischnomesidae, examples of epibenthic species (with lack of paddle-shaped legs and non/low-natatory capacity) are mainly linked to mainland areas with higher % organic matter …


Assessing The Influence Of International Environmental Treaty Secretariats Using A Relational Network Approach, Andrew M. Song, Owen Temby, Dongkyu Kim, Gordon M. Hickey Sep 2020

Assessing The Influence Of International Environmental Treaty Secretariats Using A Relational Network Approach, Andrew M. Song, Owen Temby, Dongkyu Kim, Gordon M. Hickey

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The influential role of international treaty secretariats in coordinating bureaucracies across jurisdictional boundaries has been highlighted in recent years. While we now better understand how their influence occurs, the field still faces a substantial difficulty in answering the basic quantitative question of “how influential?” By employing network analysis, we devised and tested a survey to quantify secretariat influence within an international environmental regime. We applied the survey tool to two transboundary fisheries governance networks in North America and here focus on the Great Lakes Fishery Commission (GLFC) as our primary case study. The results demonstrate a high ability of treaty …


High Ethanol Concentration (77 G/L) Of Industrial Hemp Biomass Achieved Through Optimizing The Relationship Between Ethanol Yield/Concentration And Solid Loading, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Donghai Wang Aug 2020

High Ethanol Concentration (77 G/L) Of Industrial Hemp Biomass Achieved Through Optimizing The Relationship Between Ethanol Yield/Concentration And Solid Loading, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Donghai Wang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

In this study, the relationships between ethanol yield/concentration and solid loading (6–21%) were investigated to enhance ethanol titer and avoid a random choice of solid loading for simultaneous saccharification and fermentation (SSF). Alkali-pretreated hemp biomass was used for SSF in four scenarios including Case I: 30 filter paper unit (FPU)-cellulase and 140 fungal xylanase unit (FXU)-hemicellulase/g-solid; Case II: 40 FPU-cellulase and 140 FXU-hemicellulase/g-solid; Case III: 30 FPU-cellulase and 140 FXU-hemicellulase/g-solid with 1% Tween80; and Case IV: 30 FPU-cellulase and 140 FXU-hemicellulase/g-solid with particle size reduction (<0.2 mm). Results showed that bioethanol yield and concentration had a negative linear (R2 = 0.76–0.93) and quadratic (R2 = 0.96–0.99) correlation with solid …


Imidacloprid Movement Into Fungal Conidia Is Lethal To Mycophagous Beetles, Robin A. Choudhury, Andrew M. Sutherland, Matt J. Hengel, Michael P. Parrella, W. Douglass Gubler Aug 2020

Imidacloprid Movement Into Fungal Conidia Is Lethal To Mycophagous Beetles, Robin A. Choudhury, Andrew M. Sutherland, Matt J. Hengel, Michael P. Parrella, W. Douglass Gubler

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Applications of systemic pesticides can have unexpected direct and indirect effects on nontarget organisms, producing ecosystem-level impacts. We investigated whether a systemic insecticide (imidacloprid) could be absorbed by a plant pathogenic fungus infecting treated plants and whether the absorbed levels were high enough to have detrimental effects on the survival of a mycophagous beetle. Beetle larvae fed on these fungi were used to assess the survival effects of powdery mildew and imidacloprid in a factorial design. Fungal conidia were collected from treated and untreated plants and were tested for the presence and concentration of imidacloprid. The survival of beetles fed …


Reaching 1.5 And 2.0 ◦C Global Surface Temperature Targets Using Stratospheric Aerosol Geoengineering, Simone Tilmes, Douglas G. Macmartin, Jan T. M. Lenaerts, Leo Van Kampenhout, Laura Muntjewerf, Lili Xia, Cheryl S. Harrison, Kristen M. Krumhardt, Michael J. Mills, Ben Kravitz, Alan Robock Jul 2020

Reaching 1.5 And 2.0 ◦C Global Surface Temperature Targets Using Stratospheric Aerosol Geoengineering, Simone Tilmes, Douglas G. Macmartin, Jan T. M. Lenaerts, Leo Van Kampenhout, Laura Muntjewerf, Lili Xia, Cheryl S. Harrison, Kristen M. Krumhardt, Michael J. Mills, Ben Kravitz, Alan Robock

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

A new set of stratospheric aerosol geoengineering (SAG) model experiments has been performed with Community Earth System Model version 2 (CESM2) with the Whole Atmosphere Community Climate Model (WACCM6) that are based on the Coupled Model Intercomparison Project phase 6 (CMIP6) overshoot scenario (SSP5-34-OS) as a baseline scenario to limit global warming to 1.5 or 2.0 ◦C above 1850–1900 conditions. The overshoot scenario allows us to applying a peak-shaving scenario that reduces the needed duration and amount of SAG application compared to a high forcing scenario. In addition, a feedback algorithm identifies the needed amount of sulfur dioxide injections in …


Overexpression Of Strigolactone-Associated Genes Exerts Fine-Tuning Selection On Soybean Rhizosphere Bacterial And Fungal Microbiome, Fang Liu, John Hollis Rice, Valeria Lopes, Parwinder Grewal, Sarah L. Lebeis, Tarek Hewezi, Margaret E. Staton Jul 2020

Overexpression Of Strigolactone-Associated Genes Exerts Fine-Tuning Selection On Soybean Rhizosphere Bacterial And Fungal Microbiome, Fang Liu, John Hollis Rice, Valeria Lopes, Parwinder Grewal, Sarah L. Lebeis, Tarek Hewezi, Margaret E. Staton

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Strigolactones are a recently discovered class of carotenoid-derived plant hormones with a wide variety of functions, including acting as signaling molecules in the rhizosphere to promote arbuscular mycorrhizal fungi colonization and parasitic seed germination. To determine whether strigolactones influence the recruitment of microbes to the rhizosphere, we characterized both bacterial and fungal communities in response to the overexpression of genes involved in strigolactone biosynthesis (MAX1d) and signaling perception (D14 and MAX2a) in soybean (Glycine max). The amplicon sequencing-based results suggest that strigolactone overexpression lines had altered soybean rhizosphere bacteria composition at both the community …


Benchmarking And Parameter Sensitivity Of Physiological And Vegetation Dynamics Using The Functionally Assembled Terrestrial Ecosystem Simulator (Fates) At Barro Colorado Island, Panama, Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto Jun 2020

Benchmarking And Parameter Sensitivity Of Physiological And Vegetation Dynamics Using The Functionally Assembled Terrestrial Ecosystem Simulator (Fates) At Barro Colorado Island, Panama, Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Plant functional traits determine vegetation responses to environmental variation, but variation in trait values is large, even within a single site. Likewise, uncertainty in how these traits map to Earth system feedbacks is large. We use a vegetation demographic model (VDM), the Functionally Assembled Terrestrial Ecosystem Simulator (FATES), to explore parameter sensitivity of model predictions, and comparison to observations, at a tropical forest site: Barro Colorado Island in Panama. We define a single 12-dimensional distribution of plant trait variation, derived primarily from observations in Panama, and define plant functional types (PFTs) as random draws from this distribution. We compare several …


Effect Of Pecan Variety And The Method Of Extraction On The Antimicrobial Activity Of Pecan Shell Extracts Against Different Foodborne Pathogens And Their Efficacy On Food Matrices, Veerachandra K. Yemmireddy, Cameron Cason, Juan Moreira, Achyut Adhikari Jun 2020

Effect Of Pecan Variety And The Method Of Extraction On The Antimicrobial Activity Of Pecan Shell Extracts Against Different Foodborne Pathogens And Their Efficacy On Food Matrices, Veerachandra K. Yemmireddy, Cameron Cason, Juan Moreira, Achyut Adhikari

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The shells of pecans are a rich source of bioactive compounds with potential inhibitory activity against various pathogenic microorganisms. This study investigated the antimicrobial activity of pecan shell extracts as effected by the type of cultivar and the method of extraction against various foodborne bacterial pathogens. Defatted shell powders of 19 different pecan cultivars were subjected to aqueous and ethanolic extraction (1:20 w/v) procedures, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of lyophilized pecan shell extracts dissolved in deionized water containing 5% DMSO (v/v) were determined against multiple strains of Listeria monocytogenes, Salmonella enterica, and …


Potential Predictability Of Net Primary Production In The Ocean, Kristen M. Krumhardt, Nicole S. Lovenduski, Matthew C. Long, J. Y. Luo, K. Lindsay, S. Yeager, Cheryl S. Harrison Jun 2020

Potential Predictability Of Net Primary Production In The Ocean, Kristen M. Krumhardt, Nicole S. Lovenduski, Matthew C. Long, J. Y. Luo, K. Lindsay, S. Yeager, Cheryl S. Harrison

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Interannual variations in marine net primary production (NPP) contribute to the variability of available living marine resources, as well as influence critical carbon cycle processes. Here we provide a global overview of near-term (1 to 10 years) potential predictability of marine NPP using a novel set of initialized retrospective decadal forecasts from an Earth System Model. Interannual variations in marine NPP are potentially predictable in many areas of the ocean 1 to 3 years in advance, from temperate waters to the tropics, showing a substantial improvement over a simple persistence forecast. However, some regions, such as the subpolar Southern Ocean, …


Categorizing Zonal Productivity On The Continental Shelf With Nutrient-Salinity Ratios, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco Jun 2020

Categorizing Zonal Productivity On The Continental Shelf With Nutrient-Salinity Ratios, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

  • Identifying riverine influence on productivity in the northern Gulf of Mexico
  • Use of nutrient/salinity plots to differentiate inputs from two rivers
  • Verifying Rowe-Chapman (2002) hypothesis with in situ data

Abstract

Coastal ocean productivity is often dependent on riverine sources of nutrients, yet it can be difficult to determine how far the influence of the river extends. The northern Gulf of Mexico (GOM) receives freshwater and nutrients discharged mainly from the Mississippi and Atchafalaya Rivers. We used nutrient/salinity relationships to (i) differentiate the nutrient inputs of the two rivers and (ii) determine the potential extent of the zones where productivity …


A New Species Of Chromis (Teleostei: Pomacentridae) From Mesophotic Coral Ecosystems Of Rapa Nui (Easter Island) And Salas Y Gomez, Chile, Bart Shepard, Hudson T. Pinheiro, Tyler A. Y. Phelps, Erin E. Easton, Alejandro Perez-Matus, Luiz A. Rocha May 2020

A New Species Of Chromis (Teleostei: Pomacentridae) From Mesophotic Coral Ecosystems Of Rapa Nui (Easter Island) And Salas Y Gomez, Chile, Bart Shepard, Hudson T. Pinheiro, Tyler A. Y. Phelps, Erin E. Easton, Alejandro Perez-Matus, Luiz A. Rocha

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

A new species of Chromis (Teleostei: Pomacentridae) is described from three specimens collected at 90 m depth in a mesophotic coral ecosystem at Rapa Nui, Chile. Chromis mamatapara, new species, can be distinguished from its congeners by the following combination of characters: dorsal-fin rays XIV,13–14; pectoral-fin rays 18–19, third from top of fin longest; tubed lateral-line scales 18; total gill rakers on first arch 30–32; vertebrae 11þ15; and by coloration of living specimens, especially the presence of a single, pronounced, white spot, roughly the same diameter as the orbit, located where the posterior base of the dorsal fin intersects the …


The Pantropical Response Of Soil Moisture To El Niño, Kurt C. Solander, Brent D. Newman, Alessandro Carloca De Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Celleri, Jeffery Q. Chambers, Bradley O. Christoffersen May 2020

The Pantropical Response Of Soil Moisture To El Niño, Kurt C. Solander, Brent D. Newman, Alessandro Carloca De Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Celleri, Jeffery Q. Chambers, Bradley O. Christoffersen

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The 2015–2016 El Niño event ranks as one of the most severe on record in terms of the magnitude and extent of sea surface temperature (SST) anomalies generated in the tropical Pacific Ocean. Corresponding global impacts on the climate were expected to rival, or even surpass, those of the 1997–1998 severe El Niño event, which had SST anomalies that were similar in size. However, the 2015–2016 event failed to meet expectations for hydrologic change in many areas, including those expected to receive well above normal precipitation. To better understand how climate anomalies during an El Niño event impact soil moisture, …


Tipping Points Of Mississippi Delta Marshes Due To Accelerated Sea-Level Rise, Torbjörn E. Törnqvist, Krista L. Jankowski, Yong-Xiang Li, Juan L. Gonzalez May 2020

Tipping Points Of Mississippi Delta Marshes Due To Accelerated Sea-Level Rise, Torbjörn E. Törnqvist, Krista L. Jankowski, Yong-Xiang Li, Juan L. Gonzalez

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Coastal marshes are threatened by relative sea-level (RSL) rise, yet recent studies predict marsh survival even under the high rates of RSL rise expected later in this century. However, because these studies are mostly based on short-term records, uncertainty persists about the longer-term vulnerability of coastal marshes. We present an 8500-year-long marsh record from the Mississippi Delta, showing that at rates of RSL rise exceeding 6 to 9 mm year−1, marsh conversion into open water occurs in about 50 years. At rates of RSL rise exceeding ~3 mm year−1, marsh drowning occurs within a few centuries. Because present-day rates of …


Complete Mitochondrial Genome Of Carijoa Riisei (Duchassaing & Michelotti, 1860) (Octocorallia: Alcyonacea: Stolonifera: Clavulariidae), Erin E. Easton, David Hicks Apr 2020

Complete Mitochondrial Genome Of Carijoa Riisei (Duchassaing & Michelotti, 1860) (Octocorallia: Alcyonacea: Stolonifera: Clavulariidae), Erin E. Easton, David Hicks

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We report the first complete Stolonifera mitochondrial genome. Carijoa riisei (Duchassaing & Michelotti, 1860) isolate CLP2_A03 was collected by scuba at 32 m on the USTS Texas Clipper (27° 53.7827′N, 93° 36.2702′W). The complete mitogenome has the ancestral octocoral gene order for its 14 protein-coding genes, two rRNA genes, and one tRNA gene. It is 18,714 bp (30.7% A, 15.8% C, 18.8% G, and 34.7% T). Of the Alcyonacea mitogenomes published to date, it is most genetically similar (94% uncorrected) to Sinularia ceramensis Verseveldt, 1977 (NC_044122).


The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model.We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass concentrations, growth rates, and physical transport. On average, cyclones induce negative division rate anomalies that drive negative net population growth rate anomalies, reduce dilution across shallower mixed layers, and advect biomass anomalously downward via eddy-induced Ekman pumping. The opposite is true in anticyclones. Lateral transport is dominated by eddy stirring rather than eddy trapping. The net effect on anomalous biomass can …


Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We examine the effects of Southern Ocean eddies on phytoplankton cell division rates in a global, multiyear, eddy‐resolving, 3‐D ocean simulation of the Community Earth System Model. We first identify and track eddies in the simulation and validate their distribution and demographics against observed eddy trajectory characteristics. Next, we examine how simulated cyclones and anticyclones differentially modify iron, light, and ultimately population‐specific cell division rates. We use an eddy‐centric, depth‐averaged framework to explicitly examine the dynamics of the phytoplankton population across the entire water column within an eddy. We find that population‐averaged iron availability is elevated in anticyclones throughout the …


Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846, Nicole J. Figueroa, Diego F. Figueroa, David Hicks Mar 2020

Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846, Nicole J. Figueroa, Diego F. Figueroa, David Hicks

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The calanoid copepod, Acartia tonsa Dana, 1849 is one of the most abundant and well-studied estuarian species with a worldwide distribution. In this research, we use the mitochondrial cytochrome oxidase subunit I gene to study the phylogeography of A. tonsa by analyzing sequences from specimens collected in the western Gulf of Mexico (GOM) along with all sequences from previous research. We reconstruct the phylogeny for the genus Acartia Dana, 1846 and highlight numerous potential misidentifications of Acartia species deposited in GenBank. The incorrect taxonomy assigned to some of these sequences results in apparently paraphyletic relationships. This study demonstrates that A. …


Application Of Acoustical Remote Sensing Techniques For Ecosystem Monitoring Of A Seagrass Meadow, Megan S. Ballard, Kevin M. Lee, Jason D. Sagers, Gabriel R. Venegas, Andrew R. Mcneese, Preston S. Wilson, Abdullah Rahman Mar 2020

Application Of Acoustical Remote Sensing Techniques For Ecosystem Monitoring Of A Seagrass Meadow, Megan S. Ballard, Kevin M. Lee, Jason D. Sagers, Gabriel R. Venegas, Andrew R. Mcneese, Preston S. Wilson, Abdullah Rahman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Seagrasses provide a multitude of ecosystem services and serve as important organic carbon stores. However, seagrass habitats are declining worldwide, threatened by global climate change and regional shifts in water quality. Acoustical methods have been applied to assess changes in oxygen production of seagrass meadows since sound propagation is sensitive to the presence of bubbles, which exist both within the plant tissue and freely floating the water as byproducts of photosynthesis. This work applies acoustic remote sensing techniques to characterize two different regions of a seagrass meadow: a densely vegetated meadow of Thalassia testudinum and a sandy region sparsely populated …


Subsea 2019 Expedition To The Gorda Ridge, Darlene S. S. Lim, Nicole A. Raineault, John A. Breier, Eric W. Chan, Josh Chernov, Tamar Cohen, Matthew Deans, Angela Garcia, Christopher R. German, Michelle Hauer Mar 2020

Subsea 2019 Expedition To The Gorda Ridge, Darlene S. S. Lim, Nicole A. Raineault, John A. Breier, Eric W. Chan, Josh Chernov, Tamar Cohen, Matthew Deans, Angela Garcia, Christopher R. German, Michelle Hauer

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The SUBSEA (Systematic Underwater Biogeochemical Science and Exploration Analog) program blends ocean exploration with “ocean worlds” research, along with NASA analog and work studies research, to address science, science operations, and technology knowledge gaps related to the exploration of our solar system. The science group researches venting fluids at isolated seamounts and spreading ridges in the Pacific Ocean as analog environments to putative volcanically hosted hydrothermal systems on other “ocean worlds” (defined as places in the outer solar system that could possess subsurface oceans). The science operations research group studies E/V Nautilus architecture, distributed teams, communication, and lowlatency telerobotics. The …


Implications Of Different Nitrogen Input Sources For Potential Production And Carbon Flux Estimates In The Coastal Gulf Of Mexico (Gom) And Korean Peninsula Coastal Waters, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco, Daniel C. O. Thornton Jan 2020

Implications Of Different Nitrogen Input Sources For Potential Production And Carbon Flux Estimates In The Coastal Gulf Of Mexico (Gom) And Korean Peninsula Coastal Waters, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco, Daniel C. O. Thornton

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The coastal Gulf of Mexico (GOM) and coastal sea off the Korean Peninsula (CSK) both suffer from human-induced eutrophication. We used a nitrogen (N) mass balance model in two different regions with different nitrogen input sources to estimate organic carbon fluxes and predict future carbon fluxes under different model scenarios. The coastal GOM receives nitrogen predominantly from the Mississippi and Atchafalaya rivers and atmospheric nitrogen deposition is only a minor component in this region. In the CSK, groundwater and atmospheric nitrogen deposition are more important controlling factors. Our model includes the fluxes of nitrogen to the ocean from the atmosphere, …


Bacterial Community Dissimilarity In Soils Is Driven By Long-Termland-Use Practices, Aditi Sengupta, Janani Hariharan, Parwinder Grewal, Warren A. Dick Jan 2020

Bacterial Community Dissimilarity In Soils Is Driven By Long-Termland-Use Practices, Aditi Sengupta, Janani Hariharan, Parwinder Grewal, Warren A. Dick

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Land‐use practices impact soil microbial functionality and biodiversity, with reports suggesting that anthropogenic activities potentially result in reduced microbial functions and loss of species. The objective of this study was to assess the effect of long‐term (>50 yr) land use (natural forest and grassland, and agricultural land) on soil bacterial community structure. A high‐throughput sequencing‐by‐synthesis approach of the 16S rRNA gene was used to study bacterial community and predicted functional profiles of Alfisols, as affected by variables including land‐use (forest, grass, agricultural) and soil/crop management (rotation and tillage) in long‐term experimental plots in Hoytville, OH. The distribution of the …


Coral Reefs In The Gulf Of Mexico Large Marine Ecosystem: Conservation Status, Challenges, And Opportunities, Diego L. Gil-Agudelo, Carlos E. Cintra-Buenrostro, Jorge Brenner, Patricia Gonzalez-Diaz, William Kiene, Caitlin Lustic, Horacio Perez-Espana Jan 2020

Coral Reefs In The Gulf Of Mexico Large Marine Ecosystem: Conservation Status, Challenges, And Opportunities, Diego L. Gil-Agudelo, Carlos E. Cintra-Buenrostro, Jorge Brenner, Patricia Gonzalez-Diaz, William Kiene, Caitlin Lustic, Horacio Perez-Espana

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The importance of coral reefs (CR) within marine ecosystems has become widely recognized. Although shallow CR are not as abundant in the Gulf of Mexico (GoM) as in other areas such as the Caribbean, their uniqueness, singularity, isolation, and conservation status make their conservation highly important. Corals and CR, both shallow and deep, are more widely distributed throughout the GoM than previously thought, providing new venues of research but also new challenges for their sustainable management. They are widely present in the three countries circumscribing the GoM (Cuba, Mexico, and the United States). Corals are also distributed throughout different depths, …


Additions To Philippine Slender Skinks Of The Brachymeles Bonitae Complex (Reptilia: Squamata: Scincidae) Iv: Resurrection And Redescription Of Brachymeles Burksi, Cameron D. Siler, Elyse S. Freitas, Jennifer A. Sheridan, Stephanie N. Maguire, Drew R. Davis, Jessa L. Watters, Kai Wang, Arvin C. Diesmos, Rafe M. Brown Jan 2020

Additions To Philippine Slender Skinks Of The Brachymeles Bonitae Complex (Reptilia: Squamata: Scincidae) Iv: Resurrection And Redescription Of Brachymeles Burksi, Cameron D. Siler, Elyse S. Freitas, Jennifer A. Sheridan, Stephanie N. Maguire, Drew R. Davis, Jessa L. Watters, Kai Wang, Arvin C. Diesmos, Rafe M. Brown

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The diversity of Philippine amphibians and reptiles has increased over the last few decades, in part due to re-evaluation of species formerly believed to be widespread. Many of these investigations of widespread species have uncovered multiple closely related cryptic lineages comprising species complexes, each restricted to individual Pleistocene Aggregate Island Complexes (PAICs). One group in particular for which widespread cryptic diversity has been common is the clade of Philippine skinks of the genus Brachymeles. Recent phylogenetic studies of the formerly recognized widespread species Brachymeles bonitae have indicated that this species is actually a complex distributed across several major PAICs and …


Ants Increase Cloverworm Herbivory Via Nonconsumptive Pathways, Hannah J. Penn, Kacie J. Athey Jan 2020

Ants Increase Cloverworm Herbivory Via Nonconsumptive Pathways, Hannah J. Penn, Kacie J. Athey

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Generalist arthropod predators often exhibit a range of intraguild interactions reducing their potential efficacy as biological control agents. These interactions may include consumptive or nonconsumptive effects that mediate the impacts of herbivores. We examined interactions among 2 generalist predators, the striped lynx spider (Oxyopes salticus Hentz; Araneae: Oxyopidae) and an ant (Lasius neoniger Emery; Hymenoptera: Formicidae), and a herbivore, the green cloverworm (Hypena scabra F.; Lepidoptera: Erebidae), all prevalent in central Kentucky soybean agroecosystems. We hypothesized that individual predator treatments would reduce green cloverworm survival and resultant leaf damage, but that predators would interfere with each other when both were …