Life Sciences Commons^™

The Effect Of Saltwater Stress On The Performance Of Cherry Tomatoes, Samarah R. Martin, Ivan Oyege, Kateel G. Shetty, Krish Jayachandran, Maruthi Sridhar Balaji Bhaskar

FIU Undergraduate Research Journal

Rising sea levels and saltwater intrusion in aquifers pose significant challenges for South Florida agriculture, leading to increased groundwater salinity and potential crop losses. Utilizing salttolerant crop species presents a potential solution for saline soils and regions with active saltwater intrusion. However, the effects of soil salinization through groundwater alone remains less studied. This research investigates the impact of short-term, below-ground saltwater stress on the growth, survival, and overall health of commonly grown cherry tomatoes (Solanum lycopersicum). The objectives of the study are to: 1) determine the impact of saline groundwater on tomato plant health and 2) compare the nutrient …

Bioinformatic Comparison And Salinity Tolerance Of Various Cyanobacterial Strains, Lucie Rowe

Honors Theses

Cyanobacteria are an abundant and diverse group of photosynthetic prokaryotes with a long evolutionary history, which presents challenges for comprehensive taxonomic classification. Phylogenies were traditionally constructed based on the highly conserved 16S rRNA gene, but research has increasingly relied upon whole genome sequencing to elucidate evolutionary relationships, despite increased cost and time. In this thesis, publicly available genome sequences of various cyanobacterial strains were utilized to determine if the whole rRNA region, which includes the 16S, 23S, and 5S genes as well as the spacer regions between, could provide accurate, yet cost/time efficient representations of their evolutionary relationships. From phylogenetic …

Revegetation Strategies For Native Wetland Plant Restoration In The Face Of Phragmites Australis Reinvasion And Hydrologic Extremes, Maddie Houde

All Graduate Theses and Dissertations, Fall 2023 to Present

Reestablishing native plant communities in degraded habitats through seeding or planting ("revegetation") is a necessary step to restore ecosystems and their functions (e.g., supporting biodiversity, nutrient cycling, etc.). Globally, wetlands have suffered high rates of degradation and also experience numerous invasions. Invasive species are those that cause environmental, economic, or societal harm. Phragmites australis is a widespread invasive species that outcompetes native plants and reduces habitat diversity. Reestablishing native plant communities can limit P. australis invasion, yet effective methods to do so remain somewhat untested in wetlands. Additionally, stressful environmental conditions can increase plant mortality in revegetation efforts. In semi-arid …

Paralog Switching Facilitates Diadromy: Ontogenetic, Microevolutionary And Macroevolutionary Evidence, Rebecca S. Colby, Stephen D. Mccormick, Jonathan P. Velotta, Elizabeth Jockusch, Eric T. Schultz

EEB Articles

Euryhalinity is present in diverse aquatic taxa and requires flexible osmoregulation to field the challenges posed by differing salinities. Na+, K+-ATPase (NKA) is a ubiquitous ion pump in the gills of fishes and, for some species, paralogs of the catalytic -subunit (NKA 1a and NKA 1b) exhibit reciprocal expression between fresh- and seawater, termed paralog-switching. We investigated the expression and evolution of NKA paralogs in Alewife (Alosa pseudoharengus), a euryhaline and migratory fish. Comparisons between landlocked and diadromous life history forms and migrant and pre-migrant ontogenetic stages were used to study shifts in NKA paralog expression related to freshwater or …

An Integrative Salt Marsh Conceptual Framework For Global Comparisons, Erik S. Yando, Scott F. Jones, W. Ryan James, Denise D. Colombano, Diana I. Montemayor, Stefanie Nolte, Jacqueline L. Raw, Shelby L. Ziegler, Luzhen Chen, Daniele Daffonchio, Marco Fusi, Kerrylee Rogers, Liudmila Sergienko

Biological Sciences Faculty Publications

Salt marshes occur globally across climatic and coastal settings, providing key linkages between terrestrial and marine ecosystems. However, salt marsh science lacks a unifying conceptual framework; consequently, historically well-studied locations have been used as normative benchmarks. To allow for more effective comparisons across the diversity of salt marshes, we developed an integrative salt marsh conceptual framework. We review ecosystem-relevant drivers from global to local spatial scales, integrate these multi-scale settings into a framework, and provide guidance on applying the framework using specific variables on 11 global examples. Overall, this framework allows for appropriate comparison of study sites by accounting for …

Salt Marsh Plant Community Structure On Horse Island, South Carolina, Mackenzie L. Jenkins, Jennifer L. Schafer

Journal of the South Carolina Academy of Science

Sea level rise is causing an increase in salt water encroachment and flooding in many coastal habitats, and increasing salinity can have negative impacts on plant communities. The objective of our research was to determine the impact of salinity on salt marsh plant community structure on Horse Island, South Carolina. We investigated variation in plant cover and height with distance from a tidal creek and the effect of increasing salinity on seedling emergence from the seed bank. We established three transects in the salt marsh habitat and recorded plant species presence, percent cover of each species, and height of the …

Patterns Of Evolutionary Conservation And Divergence In The Short-Term Hyposalinity Stress Response Of A Euryhaline Diatom, Skeletonema Marinoi, Kathryn Judy

Graduate Theses and Dissertations

Survival under fluctuating environmental conditions, such as those increasing in frequency and magnitude under environmental change, requires a successful response to stress. Interspecific differences in stress responses may result in differential survival of species, even within a lineage. Diatoms may constitute one such lineage, as salinity tolerance among extant species is diverse, and the observation of frequent historic habitat transitions between marine and freshwater environments indicates that diatoms successfully mitigated (low) salinity stress in the past, followed by adaptation and diversification over evolutionary time scales. To understand to what extent the diatom hypoosmotic stress response consists of conserved and variable …

Effects Of Water Quality On Oyster Health On Georgia Coast, Laurel Henderson

Honors College Theses

ABSTRACT

Oysters are an economically and ecologically important shellfish species found along most coastlines. Along the Georgia coastline, oysters form extensive reefs, and are economically important as a food source. In addition, oysters perform a vital role in maintaining water quality due to their high filtration capacity in coastal waters. Oyster reefs form solid, 3-D substrate that prevent coastline erosion and provide structure for numerous other coastal species to grow, including many commercially and recreationally important species. Water quality factors, such as temperature and salinity, can influence oyster density, condition, and growth, and ultimately affect the services the reefs provide …

An Environmental Study To Adapt Some Hadhramout Coast Plant For Drought And Salinity Tolerance, Fatehia Ali Bashantoof, Ahmed Sbit Bamousy, Abdulkarim Saber Ali

Hadhramout University Journal of Natural & Applied Sciences

The study was conducted between May 2016-August 2017. An auger was used to collect 60 random soil samples to carry out the physical and chemical analyses. The selected plants were Salola baryosma and Aeurops lagopoides in the salt marsh and Prosopis juliflora and Calotropis procera in the valleys. The results revealed clear physical and chemical differences within the soils of the salt marshes and valleys that prove to be sandy, loamy, basic and saline. All investigated variables differ in the selected areas e.g. % of sand, silt, clay. The soil of all the salt marshes was devoid of gravel which …

How A Simple Question About Freshwater Inflow To Estuaries Shaped A Career, Paul A. Montagna

Gulf and Caribbean Research

Chance and good luck led to a career studying how freshwater inflow drives estuary processes. In 1986, someone asked me: How much fresh water has to flow to a bay for it to be healthy? The question shaped my career. There is probably no better place on Earth to compare effects caused by inflow differences than the Texas coast, because the major estuarine systems lie in a climatic gradient where runoff decreases 56—fold from the Louisiana border in the northeast to the Mexico border in the southwest. This estuary—comparison experiment was used to study inflow effects. The science evolved from …

Crop Salinity Tolerance Induction Using Novel Biostimulants (Saltibio), Elomofe Ikuyinminu

Theses

Salinity is one of the major abiotic stresses affecting crop production, especially in arid and semi-arid areas. Most of the vegetable crops are salt sensitive, growing inadequately in salinised soils due to the accumulation of toxic ions from prolonged, inadequate irrigation programs. A meaningful approach to counteract salinity stress and increase crop yield is the use of protein hydrolysate biostimulants (PHBs). The main objectives of this study were to generate legume-derived PHBs by enzymatic hydrolysis, evaluate their ability to induce salinity stress tolerance in plants, and understand their mode of action. A full compositional and structural analysis of the generated …

Determining The Physiological And Behavioral Responses To Elevated Salinity In The Freshwater Bivalves, Corbicula Fluminea And Lampsilis Ovata, John W. Roden

Electronic Theses and Dissertations

Salinization has been identified as an increasing threat to freshwater mussel diversity in recent years. Native mussels have been observed to display reduced salinity tolerance in comparison to some invasive bivalve species, but methods by which organismal tolerance is achieved are not well understood. This study was designed to compare the behavioral and physiological responses of the native Lampsilis ovata to that of the invasive Corbicula fluminea. Lampsilis were found to exhibit strong behavioral avoidance to salinity exposure, whereas Corbicula displayed very weak avoidance to comparable salinity concentrations followed by indications of osmotic conformation through physiological mechanisms. Prolonged valve …

Investigating The Effects Of Sea-Level Rise And Increasing Salinity On Procambarus Lunzi Of Sapelo Island, Georgia, Samuel Long

Biology Theses

Barrier islands have great ecological and economical importance and face a threat from increasing sea-level due to climate change. Erosion of existing freshwater lens and ocean inundation could greatly change freshwater availability on the island. This could have significant impacts on freshwater crayfish like Procambarus lunzi, which are complexly intertwined into the trophic food web of the island. This study’s goal was to investigate the salinity tolerance of this crayfish on Sapelo Island, Georgia, in an attempt to predict the possible effects and response to sea-level rise by this crayfish. Crayfish were wild-caught from the island in March, June, and …

Salinity Reduces The Forage Quality Of Forage Kochia: A Halophytic Chenopodiaceae Shrub, Blair L. Waldron, Joseph K. Sagers, Michael D. Peel, Craig W. Rigby, Bruce G. Bugbee, Joseph E. Creech

Forage and Range Research Laboratory Publications

Forage kochia (Bassia prostrata [L.] A.J. Scott) is a perennial, halophytic Chenopodiaceae shrub adapted to semiarid rangelands and steppes. It is noted for its ability to produce edible forage in saline environments, but the effect of salinity on its nutritive value has not been determined. Therefore, this study evaluated the dose-response of increasing salinity on the forage quality of forage kochia and Gardner’s saltbush (Atriplex gardneri [Moq.] D. Dietr., a chenopod forage shrub indigenous to the United States). Individual plants were evaluated in hydroponics for 28 days at 0, 150, 300, and 600 mM NaCl. Salt from accumulated …

Can Zooplankton On The North American Great Plains ‘Keep Up’ With Climate-Driven Salinity Change?, Mariam Elmarsafy

Theses and Dissertations (Comprehensive)

The Great Plains of North America are projected to become more arid as the climate changes over the next century. Salinity levels for lakes in this region are linked to climate, suggesting that lakes will become more saline as the climate becomes drier. One group of organisms that might be affected by increased salinity levels are the zooplankton, aquatic invertebrates that transfer energy from primary producers to macroinvertebrates and fish. Little is known about the ability of zooplankton to adapt to long-term increases in lake salinity levels. For my thesis, I used resurrection ecology to examine how a common zooplankter, …

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger

University of New Orleans Theses and Dissertations

Salinity (S) and temperature (T) control every facet of the eastern oyster (Crassostrea virginica) life cycle, principally reproduction, development, growth, and mortality. Previous studies conducted in in the Breton Sound (BR) and Barataria (BA) estuaries have reported differences in growth and mortality rates between the basins. In the present study, environmental conditions were synchronized to compare growth and mortality rates between basins at similar combinations of T and S. Results indicate that when T and S are the same (synchronized), seasonal oyster growth and mortality rates differ between BR and BA. Seasonal analyses revealed that as salinities increased …

Effect Of Adult Chemical Cues On Molting Of Fiddler Crab Megalopae In Low Salinity Seawater, Sydney Rilum

Undergraduate Honors Theses

Three species of fiddler crabs, Uca minax, U. pugnax, and U. pugilator, are commonly found in estuaries along the Atlantic coast, each with distinct adult habitats differing in salinity and sediment grain size. Prior research has found evidence for larvae exhibiting selective settlement; however, the degree to which and the method by which they choose their species-appropriate habitat to settle in is still unknown. Additionally, a recent study determined that chemical cues from adult crabs stimulate molting in field-caught fiddler crab megalopae, as previously determined in lab-reared megalopae; however, in 35 ppt seawater, few U. minax molted. …

Determining The Physiological And Behavioral Aspects Of Salinity Tolerance In The Asian Clam, Corbicula Fluminea, John Roden

Undergraduate Honors Theses

The Asian clam, Corbicula fluminea, is an invasive bivalve species that now occurs through most of the lower 48 United States. While a significant degree of salinity tolerance has been observed in C. fluminea, owing to its estuarine lineage, the physiological and behavioral responses to changes in salinity by these organisms are not completely understood. It was hypothesized that Corbicula would initially avoid elevated salinity levels (>1 g/L) behaviorally through valve closure, but would eventually have to open to dispel anaerobic waste products and deal with the salinity. To explore this, Corbicula were collected and put through …

Recent Conditions Highlight Regional Differences In Temperature, Salinity And Dissolved Oxygen Between Strait Of Juan De Fuca And Puget Sound Sites Under Anomalous 2014-2017 Climate Patterns, Julia Bos, Christopher Krembs, S. L. Albertson, Mya Keyzers, Allison Brownlee, Carol Maloy

Salish Sea Ecosystem Conference

Understanding impacts of climate change on Salish Sea water quality is critical yet challenging due to the complexity, strength and diversity of influences on circulation and mixing. Different extreme climate conditions in recent years (2014-2017) include record warm temperatures with reduced snow pack in 2014-2015 followed by a few years of alternating summer droughts with record rainy seasons. These conditions influenced marine water temperature, salinity and dissolved oxygen (DO) throughout the Salish Sea. Analyses reveal distinct differences in these key physical and chemical characteristics between Strait of Juan de Fuca sites and sites within Puget Sound basins. Extremely low DO …

Determining The Physiological And Behavioral Methods Of Salinity Tolerance In Corbicula Fluminea, John Warren Roden Iii

Appalachian Student Research Forum

While a significant degree of salinity tolerance has been observed in the bivalve mollusk species Corbicula fluminea, the physiological and behavioral responses to changes in salinity by these organisms are not completely understood. It was hypothesized that Corbicula would initially avoid any salinity stress behaviorally through valve closure, but would eventually have to open to dispel anaerobic waste products and deal with the salinity. To explore this, Corbicula were collected and put through a series of experiments at salinity exposures of 0, 2.5, and 5.0ppt, with tissue water content and hemolymph osmolality being measured. After an initial 96-hour exposure …

Analysis Of Submerged Aquatic Vegetation Resources Across The Northern Gulf Of Mexico: Communities And Biomass, Eva R. Hillmann

LSU Doctoral Dissertations

Submerged aquatic vegetation (SAV) provides many critical ecosystem services, yet we lack basic information on SAV assemblages, biomass and diversity across expansive coasts such as the northern Gulf of Mexico (nGoM). This research investigated SAV along the nGoM from 2013-2015 examining (1) inter-annual variation in SAV assemblages and biomass across salinity zones and gulf coast eco-regions (Texas Mid-Coast, Texas/LA Chenier Plain, Louisiana Delta, MS/AL), (2) intra-annual variation in SAV assemblages and biomass across salinity zones, (3) response of two species, Ruppia maritima and Myriophyllum spicatum, to salinity and light regimes, and (4) estimated organic carbon stock and storage of …

Drivers And Mechanisms Of Peat Collapse In Coastal Wetlands, Benjamin J. Wilson

FIU Electronic Theses and Dissertations

Coastal wetlands store immense amounts of carbon (C) in vegetation and sediments, but this store of C is under threat from climate change. Accelerated sea level rise (SLR), which leads to saltwater intrusion, and more frequent periods of droughts will both impact biogeochemical cycling in wetlands. Coastal peat marshes are especially susceptible to saltwater intrusion and changes in water depth, but little is known about how exposure to salinity affects organic matter accumulation and peat stability. I investigated freshwater and brackish marsh responses to elevated salinity, greater inundation, drought, and increased nutrient loading. Elevated salinity pulses in a brackish marsh …

The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak

FIU Electronic Theses and Dissertations

Coastal forest retreat in the Florida Keys during the 20^th century has been attributed to a combination of sea level rise and hurricane storm surge impacts, but the interactions between these two disturbances leading to forest decline are not well understood. The goal of my research was to assess their effects over a period spanning more than two decades, and to examine the relationships between these press and pulse disturbances and freshwater availability in pine rockland, hardwood hammock, and supratidal scrub communities. Impacts and recovery from two storm surges, Hurricanes Georges (1998) and Wilma (2005), were assessed with satellite-derived …

Physiological Response To Salinity Challenge Is Mediated By Na+, K+ - Atpase “Isoform Switching” In A Euryhaline Fish, The Alewife, Rebecca S. Colby

Honors Scholar Theses

Na⁺, K⁺-ATPase (NKA) a1a and a1b expression was investigated in Alewives in response to salinity challenge. Anadromous and landlocked Alewives were exposed to freshwater (0ppt) and seawater (30ppt) treatments and sampled at 2-, 5-, and 15-day time points. Anadromous alewives exhibit significant up-regulation of a1a in freshwater compared to seawater at all time points, and significant up-regulation of a1b in seawater compared to freshwater at all time points. In landlocked Alewives, a1a is significantly up regulated at the 5-day time point and a1b is significantly up regulated at all time points (in their respective salinities). Analysis …

Salinity Distribution Of Microplankton In The San Francisco Estuary, Carrie Ann Sharitt, Lindsay Sullivan, Wim Kimmerer

STAR Program Research Presentations

Microplankton are a diverse group of planktonic organisms ranging from 0.02 to 0.2 millimeters. Since the group is defined solely by size, it spans numerous taxonomic groups, including both heterotrophs and autotrophs. Microplankton are abundant in all aquatic ecosystems and are important prey for many organisms, including bivalves, crustaceans, and fish. The San Francisco Bay is truly an estuary as saltwater enters the estuary under the Golden Gate Bridge and freshwater flows in from the Sacramento and San Joaquin Rivers. Thus, there is a gradient of salinity from freshwater (0) in the rivers to saltwater by the Golden Gate Bridge …

Characterization Of Rhizobial Diversity And Relationship Of Rhizobial Partner And Legume Performance In Four South Florida Pine Rockland Soils, Vanessa Sánchez

FIU Electronic Theses and Dissertations

Pine rocklands are endangered ecosystems unique to south Florida, the Bahamas and Cuba. As a result of their karstic calcium carbonate­rich soil, these systems are limited in phosphorus and nitrogen, making symbiotic associations critical to plant growth. Four leguminous species (Cajanus cajan, Chamaecrista fasciculata, Tephrosia angustissima, and Abrus precatorious) were used to determine the relationship between rhizobial partners and plant performance, and the symbiosis related gene nifH was amplified to characterize the diversity of rhizobial symbionts. Plants were grown in soils from four different south Florida pine rocklands, and a salinity treatment was added to determine …

Water Column Ammonium Concentration And Salinity Influence Nitrogen Uptake And Growth Of Spartina Alterniflora, Rachel Mactavish

Electronic Theses and Dissertations

Salt marsh macrophytes, such as Spartina alterniflora, play a critical role in uptake and transformation of inorganic nitrogen before it reaches coastal waters, thereby reducing the potential for eutrophication. Although nitrogen availability typically limits S. alterniflora growth, it may be possible to exceed the nitrogen uptake capacity of S. alterniflora. Increasing either nitrogen concentrations or salinity are key factors regulating S. alterniflora nitrogen uptake. Investigating the effects of nutrients and salinity on S. alterniflora is important given that increases in inorganic nitrogen supply to surface waters from agriculture and urbanization occur simultaneously with freshwater withdrawals that reduce flow and increase …

Assessing The Responses Of Adult, Juvenile, And Larval Fish Assemblages To The Closure Of The Mississippi River Gulf Outlet, An Artificial Tidal Pass In Southeastern Louisiana, Rebecca Weatherall Cope

University of New Orleans Theses and Dissertations

The creation of the Mississippi River Gulf Outlet (MRGO) in 1963 by the U.S. Army Corps of Engineers (USACE) represents one of the most catastrophic, anthropogenic stressors ever to impact the Lake Pontchartrain estuary in southeastern Louisiana, USA. The artificial tidal pass provided a direct route from the Gulf of Mexico to New Orleans. It allowed for high saline waters to enter Lake Pontchartrain, resulting in detrimental changes to the biotic community of the Lake and surrounding wetland areas. In July 2009, the USACE closed the MRGO in hopes of restoring natural ecosystems. This study assesses changes in the adult, …

Effects Of Salinity On The Toxicity Of Ionic Silver And Ag-Pvp Nanoparticles To Tisbe Battagliai And Ceramium Tenuicorne, Ailbhe Macken, Hugh Byrne, Kevin Thomas

Articles

The toxic effects of polyvinylpyrrolidone (PVP) coated silver nanoparticles (Ag-NP_PVP) and ionic Ag, to Tisbe battagliai (Tb) and Ceramium tenuicorne (Ct) were investigated and the usefulness of standardised marine guidelines for ENP risk assessment were assessed. The toxicity of Ag-NP_PVP [CtEC₅₀ = 26.6 µg/L, TbEC₅₀ = 7.9 µg/L] and Ag⁺ [CtEC₅₀ = 2312.2µg/L, Tb EC₅₀ = 90.9 µg/L] to both test species differed, with the silver ENPs being more toxic. In contrast to Ag⁺ the toxicity of Ag-NP_PVP increased significantly with increasing salinity, however, after thorough characterisation it was not …