Life Sciences Commons^™

Algal Biomarkers As A Proxy For Pco2: Constraints From Late Quaternary Sapropels In The Eastern Mediterranean, Caitlyn R. Witkowski, Marcel T.J. Van Der Meer, Brian Blais, Jaap S. Sinninghe Damsté, Stefan Schouten

Science and Technology Department Faculty Journal Articles

Records of carbon dioxide concentrations (partial pressure expressed as pCO2) over Earth’s history provide trends that are critical to understand our changing world. To better constrain pCO2 estimations, here we test organic pCO2 proxies against the direct measurements of pCO2 recorded in ice cores. Based on the concept of stable carbon isotopic fractionation due to photosynthetic CO2 fixation (Ɛp), we use the stable carbon isotopic composition (δ13C) of the recently proposed biomarker phytol (from all photoautotrophs), as well as the conventionally used alkenone biomarkers (from specific species) for comparison, to reconstruct pCO2 over several Quaternary …

Tree Mode Of Death And Mortality Risk Factors Across Amazon Forests, Adriane Esquivel-Muelbert, Oliver Phillips, Roel Brienen, Sophie Fauset, Martin Sullivan, Timothy Baker, Kuo-Jung Chao, Ted Feldpausch, Emanuel Gloor, Niro Higuchi, Jeanne Houwing-Duistermaat, Jon Lloyd, Haiyan Liu, Yadvinder Malhi, Beatriz Marimon, Ben Hur Marimon Junior, Abel Monteagudo-Mendoza, Lourens Poorter, Marcos Silveira, Emilio Vilanova Torre, Esteban Alvarez Dávila, Jhon Del Aguila Pasquel, Everton Almeida, Patricia Alvarez Loayza, Ana Andrade, Luiz E. O. C. Aragão, Alejandro Araujo-Murakami, Eric Arets, Luzmila Arroyo, Gerardo A. Aymard C., Michel Baisie, Christopher Baraloto, Plínio Barbosa Camargo, Jorcely Barroso, Lilian Blanc, Damien Bonal, Frans Bongers, René Boot, Foster Brown, Benoit Burban, José Luís Camargo, Wendeson Castro, Victor Chama Moscoso, Jerome Chave, James Comiskey, Fernando Cornejo Valverde, Antonio Lola Da Costa, Nallaret Davila Cardozo, Anthony Di Fiore, Aurélie Dourdain, Terry Erwin, Gerardo Flores Llampazo, Ima Célia Guimarães Vieira, Rafael Herrera, Eurídice Honorio Coronado, Isau Huamantupa-Chuquimaco, Eliana Jimenez-Rojas, Timothy Killeen, Susan Laurance, William Laurance, Aurora Levesley, Simon L. Lewis, Karina Liana Lisboa Melgaço Ladvocat, Gabriela Lopez-Gonzalez, Thomas Lovejoy, Patrick Meir, Casimiro Mendoza, Paulo Morandi, David Neill, Adriano José Nogueira Lima, Percy Nuñez Vargas, Edmar Almeida De Oliveira, Nadir Pallqui Camacho, Guido Pardo, Julie Peacock, Marielos Peña-Claros, Maria Cristina Peñuela-Mora, Georgia Pickavance, John Pipoly Iii, Nigel Pitman, Adriana Prieto, Thomas A. M. Pugh, Carlos Quesada, Hirma Ramirez-Angulo, Simone Matias De Almeida Reis, Maxime Rejou-Machain, Zorayda Restrepo Correa, Lily Rodriguez Bayona, Agustín Rudas, Rafael Salomão, Julio Serrano, Javier Silva Espejo, Natalino Silva, James Singh, Clement Stahl, Juliana Stropp, Varun Swamy, Joey Talbot, Hans Ter Steege, John Terborgh, Raquel Thomas, Marisol Toledo, Armando Torres-Lezama, Luis Valenzuela Gamarra, Geertje Van Der Heijden, Peter Van Der Meer, Peter Van Der Hout, Rodolfo Vasquez Martinez, Simone Aparecida Vieira, Jeanneth Villalobos Cayo, Vincent Vos, Roderick Zagt, Pieter Zuidema, David Galbraith

Marine & Environmental Sciences Faculty Articles

The carbon sink capacity of tropical forests is substantially affected by tree mortality. However, the main drivers of tropical tree death remain largely unknown. Here we present a pan-Amazonian assessment of how and why trees die, analysing over 120,000 trees representing > 3800 species from 189 long-term RAINFOR forest plots. While tree mortality rates vary greatly Amazon-wide, on average trees are as likely to die standing as they are broken or uprooted—modes of death with different ecological consequences. Species-level growth rate is the single most important predictor of tree death in Amazonia, with faster-growing species being at higher risk. Within species, …

Weather And Climate Summary And Forecast: September 2020 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for September 2020. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.

Perspective Article: Actions To Reconfigure Food Systems, Ana Maria Loboguerrero, Philip Thornton, Jonathan Wadsworth, Bruce M. Campbell, Mario Herrero, Daniel Mason-D'Croz, Dhanush Dinesh, Sophia Huyer, Andy Jarvis, Alberto Millan, Eva Wollenberg, Stephen Zebiak

Rubenstein School of Environment and Natural Resources Faculty Publications

There is broad agreement that current food systems are not on a sustainable trajectory that will enable us to reach the Sustainable Development Goals by 2030, particularly in the face of anthropogenic climate change. Guided by a consideration of some food system reconfigurations in the past, we outline an agenda of work around four action areas: rerouting old systems into new trajectories; reducing risks; minimising the environmental footprint of food systems; and realigning the enablers of change needed to make new food systems function. Here we highlight food systems levers that, along with activities within these four action areas, may …

Benefits And Tradeoffs Of Reduced Tillage And Manure Application Methods In A Zea Mays Silage System, Kyle M. Dittmer, Heather M. Darby, Tyler R. Goeschel, E. Carol Adair

College of Agriculture and Life Sciences Faculty Publications

A critical question is whether there are agricultural management practices that can attain the multiple management goals of increasing yields, preventing nutrient losses, and suppressing greenhouse gas (GHG) emissions. No-till and manure application methods, such as manure injection, can enhance nutrient retention, but both may also enhance emissions of nitrous oxide (N2O), a powerful GHG. We assessed differences in soil N2O and carbon dioxide (CO2) emissions, nitrate and ammonium retention, and crop yield and protein content under combinations of vertical-till, no-till, manure injection, and manure broadcast without incorporation in a corn (Zea mays L.) silage system. During the growing seasons …

Making A Bee-Line For Food With Octopamine, Lauren E. Nadler

Marine & Environmental Sciences Faculty Articles

No abstract provided.

Seasonal Movements And Habitat Use Of Juvenile Smooth Hammerhead Sharks In The Western North Atlantic Ocean And Significance For Management, Ryan K. Logan, Jeremy Vaudo, Lara L. Sousa, Mark Sampson, Bradley M. Wetherbee, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Articles

Upper trophic level predators dramatically impacted by fisheries include the large-bodied hammerhead sharks, which have become species of conservation concern worldwide. Implementing spatial management for conservation of hammerhead populations requires knowledge of temporal distribution patterns and habitat use, identification of essential habitat for protection, and quantification of interactions with human activities. There is little such information for the smooth hammerhead shark, Sphyrna zygaena. We used fin-mounted satellite tags to examine the movements and habitat use of juvenile smooth hammerheads, a demographic segment particularly threatened by exploitation. Six sharks were tagged off the US mid-Atlantic and tracked for 49–441 days …

The Effect Of Phytoplankton Properties On The Ingestion Of Marine Snow By Calanus Pacificus, Grace Cawley

Theses

The aggregation of phytoplankton into marine snow provides a mechanism by which smaller particles can coagulate to form larger particles, which can be consumed at various depths or readily transported to the deep ocean and sequestered from the atmosphere on time scales of a thousand years or more. Zooplankton interacting with these large carbon-rich aggregates can obtain nutrition in environments where the phytoplankton size spectrum is small and not directly available, enhancing the possibility of obtaining adequate nutrition in environments dominated by small cells. In addition, interactions between zooplankton and marine snow can result in fragmentation, thus affecting the particle …

Thermal Stress-Related Spatiotemporal Variations In High-Latitude Coral Reef Benthic Communities, Nicholas P. Jones, Joana Figueiredo, David S. Gilliam

Marine & Environmental Sciences Faculty Articles

High-latitude coral reef communities have been postulated as the first areas to undergo reorganisation under climate change. Tropicalisation has been identified in some high-latitude communities and is predicted in others, but it is unclear how the resident benthic taxa are affected. We conducted a long-term (2007–2016) assessment of changes to benthic community cover in relation to thermal stress duration on the Southeast Florida Reef Tract (SEFRT). Thermal stress events, both hot and cold, had acute (thermal stress duration affected benthic cover that year) and chronic (thermal stress duration affected benthic cover the following year) impacts on benthic cover. Chronic heat …

Snow-Albedo Feedback In Northern Alaska: How Vegetation Influences Snowmelt, Lucas C. Reckhaus

Theses and Dissertations

This paper investigates how the snow-albedo feedback mechanism of the arctic is changing in response to rising climate temperatures. Specifically, the interplay of vegetation and snowmelt, and how these two variables can be correlated. This has the potential to refine climate modelling of the spring transition season. Research was conducted at the ecoregion scale in northern Alaska from 2000 to 2020. Each ecoregion is defined by distinct topographic and ecological conditions, allowing for meaningful contrast between the patterns of spring albedo transition across surface conditions and vegetation types. The five most northerly ecoregions of Alaska are chosen as they encompass …

Effects Of Surfactants On The Generation Of Sea Spray During Tropical Cyclones, Breanna L. Vanderplow

All HCAS Student Capstones, Theses, and Dissertations

Despite significant improvement in computational and observational capabilities, predicting intensity and intensification of major tropical cyclones remains a challenge. In 2017 Hurricane Maria intensified to a Category 5 storm within 24 hours, devastating Puerto Rico. In 2019 Hurricane Dorian, predicted to remain tropical storm, unexpectedly intensified into a Category 5 storm and destroyed the Bahamas. The official forecast and computer models were unable to predict rapid intensification of these storms. One possible reason for this is that key physics, including microscale processes at the air-sea interface, are poorly understood and parameterized in existing forecast models.

Under tropical cyclones, the air-sea …

Prioritizing The Largest, Oldest Corals For Disease Intervention In A Coral Disease-Ravaged Area: Southeast Florida Coral Reef Ecosystem Conservation Area, Alysha Brunelle

All HCAS Student Capstones, Theses, and Dissertations

Coral diseases appear to be more devastating than ever before. When a virulent disease ravages a coral ecosystem, it can significantly change the population’s demographics and cause local extinctions. Disease intervention response during such an event is impossible at a landscape scale, therefore priorities must be considered. Saving the largest, oldest colonies of reef-building species is a good choice due to their high fecundity and ecological function. Their size, as a proxy for age, is an indicator of their resistance to previous perturbations which may indicate higher fitness. Their size also provides habitat to many organisms and wave resistance in …

Algal Coverage Detection And Classification Using Envi: Correlation With Dissolved Oxygen Levels In Elkhorn Slough, Ca, Jason Dawson

All HCAS Student Capstones, Theses, and Dissertations

Estuaries are exposed to varying stressors, whether they be physical, chemical, or environmental. The most notable of stressors is eutrophication of coastal and inland ecosystems. This is a result of increased supply of nutrients fueling production within the system. One outcome of this increased nutrient load to the system is that of algal blooms. These blooms can impact the aesthetic appearance and degrade the quality of health of the system. Many of these coastal zones and waterways are critical habitats for many biological (some endangered) species and serve as recreational areas for human populations. Elkhorn Slough, California is one of …

Weather And Climate Summary And Forecast: August 2020 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for August 2020. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene …

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife: Staff Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …

A Framework For Aquatic Invasive Species Surveillance Site Selection And Prioritization In The Us Waters Of The Laurentian Great Lakes, Andrew J. Tucker, W. Lindsay Chadderton, Gust Annis, Alisha D. Davidson, Joel Hoffman, Jon Bossenbroek, Stephen Hensler, Michael Hoff, Erika Jensen, Donna R. Kashian, Sarah Lesage, Timothy Strakosh

Environmental Science and Geology Faculty Research Publications

Risk-based prioritization for early detection monitoring is of utmost importance to prevent and mitigate invasive species impacts and is especially needed for large ecosystems where management resources are not sufficient to survey all locations susceptible to invasion. In this paper we describe a spatially-explicit and quantitative approach for identifying the highest risk sites for aquatic invasive species (AIS) introduction into the United States’ waters of the Laurentian Great Lakes, a vast inland sea with a surface area of 246,049 square km and a shoreline length of 16,431 km. We compiled data from geospatial metrics available across all of the US …

Relative Impacts Of Global Changes And Regional Watershed Changes On The Inorganic Carbon Balance Of The Chesapeake Bay, Pierre St-Laurent, Marjorie A.M. Friedrichs, Raymond G. Najjar, Elizabeth Shadwick, Hanquin Tian, Yuanzhi Yao

VIMS Articles

The Chesapeake Bay is a large coastal-plain estuary that has experienced considerable anthropogenic changeover the past century. At the regional scale, land-use change has doubled the nutrient input from rivers and led to an increase in riverine carbon and alkalinity. The bay has also experienced global changes, including the rise of atmospheric temperature and CO2. Here we seek to understand the relative impact of these changes on the inorganic carbon balance of the bay between the early 1900s and the early 2000s. We use a linked land–estuarine–ocean modeling system that includes both inorganic and organic carbon and nitrogen cycling. Sensitivity …

Taxonomic Richness And Diversity Of Larval Fish Assemblages In The Oceanic Gulf Of Mexico: Links To Oceanographic Conditions, Corinne R. Meinert, Kimberly Clausen-Sparks, Maëlle Cornic, Tracey Sutton, Jay R. Rooker

Marine & Environmental Sciences Faculty Articles

Biodiversity enhances the productivity and stability of marine ecosystems and provides important ecosystem services. The aim of this study was to characterize larval fish assemblages in pelagic waters of the northern Gulf of Mexico (NGoM) and identify oceanographic conditions associated with areas of increased taxonomic richness (T ) and Shannon diversity (H’). Summer ichthyoplankton surveys were conducted in the NGoM in 2015 and 2016 using neuston net (surface layer; upper 1 m) and oblique bongo net (mixed layer; 0–100 m) tows. Over 17,000 fish larvae were collected over the two-year study, and 99 families of fish larvae were present. Catch …

Brain-Encysting Trematodes (Euhaplorchis Californiensis) Decrease Raphe Serotonergic Activity In California Killifish (Fundulus Parvipinnis), Siri H. Helland-Riise, Marco A. Vindas, Ida B. Johansen, Lauren E. Nadler, Kelly L. Weinersmith, Ryan F. Hechinger, Øyvind Øverli

Marine & Environmental Sciences Faculty Articles

Modulation of brain serotonin (5-HT) signalling is associated with parasite-induced changes in host behaviour, potentially increasing parasite transmission to predatory final hosts. Such alterations could have substantial impact on host physiology and behaviour, as 5-HT serves multiple roles in neuroendocrine regulation. These effects, however, remain insufficiently understood, as parasites have been associated with both increased and decreased serotonergic activity. Here, we investigated effects of trematode Euhaplorchis californiensis metacercariae on post-stress serotonergic activity in the intermediate host California killifish (Fundulus parvipinnis). This parasite is associated with conspicuous behaviour and increased predation of killifish by avian end-hosts, as well as …

Opinion: Midwater Ecosystems Must Be Considered When Evaluating Environmental Risks Of Deep-Sea Mining, Jeffrey C. Drazen, Craig R. Smith, Kristina Gjerde, Steven Haddock, Glenn S. Carter, Anela Choy, Malcolm R. Clark, Pierre Dutrieux, Erica Goetze, Chris Hauton, Mariko Hatta, Julian Koslow, Astrid Brigitta Leitner, Aude Pacini, Jessica Nicole Perelman, Thomas Peacock, Tracey Sutton, Les Watling, Hiroyuki Yamamoto

Marine & Environmental Sciences Faculty Articles

No abstract provided.

Reproductive Effort Of Montastraea Cavernosa Across Depth In The Context Of Both Climate Change Refugia And Emergent Disease, Jeanne Bloomberg

LSU Master's Theses

As coral populations on shallow reefs decline globally, mesophotic coral ecosystems (MCE) have been suggested as potential coral refugia in the face of climate changes, leading to the development of a comprehensive deep reef refugia hypothesis. The current study assesses the climate and disease refuge potential of MCEs in the U.S. Virgin Islands (USVI) for the gonochoric, broadcast-spawning species Montastraea cavernosa. Polyp, population, and total habitat fecundities were estimated across the species’ depth range, and changes to population oocyte production over time due to recent ecosystem disturbances were considered. The number of gonads producing oocytes in each polyp and oocyte …

Weather And Climate Summary And Forecast: July 2020 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for July 2020. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.

Analysis Of The Facilitative Interaction Between Batis Maritima And Avicennia Germinans As A Mangrove Restoration Strategy, Javier R. Navarro

Theses and Dissertations

The multiple experiments conducted in an Avicennia germinans forest in Laguna Vista, TX was focused on determining if facilitation theory could explain the behavior observed between the herbaceous halophyte Batis maritima and A. germinans. I hypnotized that a positive interaction exists but through which mechanisms of facilitation I did not know. The overarching theme of the study is the presence or absence of B. maritima. Facilitation theory tells us that positive interactions are most often found under stressful conditions such as those on the coastal tidal flat of the Laguna Madre. Locally B. maritima has been found to …

Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw

Water Systems

Increasing greenhouse gas concentrations in the atmosphere, resulting in climate impacts, are raising concerns over the hydrologic cycle and its effects upon agricultural productivity. If rainfall patterns change, meeting an increased demand for fruits and vegetables will pose a challenge for domestic production regions in the United States (U.S.). Information on potential water supply scarcity in the current production regions provides decision makers with critical information for risk mitigation for future production. We used a hydrologic balance-based model of historic and future water availability to evaluate risk of available irrigation water to support major fruit and vegetable production the US. …

Shallow-Water Coral Communities Support The Separation Of Marine Ecoregions On The West-Central Florida Gulf Coast, Brian K. Walker, Shelby Eagan, Cory Ames, Sandra Brooke, Sean Keenan, Rene Baumstark

Marine & Environmental Sciences Faculty Articles

Florida’s west coast is a 170,000 km² bedrock shelf (west Florida shelf, WFS) comprised of north-south discontinuous carbonate outcroppings extending more than 200 km from the intertidal zone to a depth of 200 m. These outcrops support diverse benthic communities, which contribute to a multi-billion dollar recreational and commercial fishing industry, yet only about 5% of their extent has been studied in detail. Benthic communities shift over a 6.5° geographic range, but the locations of these shifts are not well-defined. Previous studies have suggested a break in biogeographic regions at Tampa Bay, south at Cape Romano, and north at …

Long-Term Ndvi And Recent Vegetation Cover Profiles Of Major Offshore Island Nesting Sites Of Sea Turtles In Saudi Waters Of The Northern Arabian Gulf, Rommel H. Maneja, Jeffrey D. Miller, Wenzhao Li, Hesham El-Askary, Ace Vincent B. Flandez, Joshua J. Dagoy, Joselito Francis A. Alcaria, Abdullajid U. Basali, Khaled A. Al-Abdulkader, Ronald A. Loughland, Mohamed A. Qurban

Mathematics, Physics, and Computer Science Faculty Articles and Research

Vegetation is an important ecological component of offshore islands in the Arabian Gulf (AG), which maintains long-term resilience of these islands. This is achieved by influencing sediment retention and moisture acquisition via condensation during periods of high humidity and by providing a variety of microhabitats for island fauna. The resilience of offshore islands’ ecosystems in the Saudi waters is important because they host the largest number of nesting hawksbill and green turtles in the AG. This study defines the characteristics and the long-term trends in vegetation cover of the offshore islands used by sea turtles as nesting grounds in the …

Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction, Gerardo Ceballos, Paul R. Ehrlich, Peter H. Raven

Harold W. Manter Laboratory: Library Materials

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in …

Effectiveness Of Topical Antibiotics In Treating Corals Affected By Stony Coral Tissue Loss Disease, Karen L. Neely, Kevin A. Macaulay, Emily K. Hower, Michelle A. Dobler

Marine & Environmental Sciences Faculty Articles

Since 2014, Stony Coral Tissue Loss Disease (SCTLD) has led to mass mortality of the majority of hard coral species on the Florida Reef Tract. Following the successful treatment of SCTLD lesions on laboratory corals using water dosed with antibiotics, two topical pastes were developed as vehicles to directly apply antibiotic treatments to wild corals. These pastes were tested as placebos and with additions of amoxicillin on active SCTLD lesions on multiple coral species. The effectiveness of the pastes without antibiotics (placebo treatments) was 4% and 9%, no different from untreated controls. Adding amoxicillin to both pastes significantly increased effectiveness …

Zooplankton Diel Vertical Migration During Antarctic Summer, John A. Conroy, Deborah K. Steinberg, Patrica S. Thibodeau, Oscar Schofield

VIMS Articles

Zooplankton diel vertical migration (DVM) during summer in the polar oceans is presumed to be dampened due to near continuous daylight. We analyzed zooplankton diel vertical distribution patterns in a wide range of taxa along the Western Antarctic Peninsula (WAP) to assess if DVM occurs, and if so, what environmental controls modulate DVM in the austral summer. Zooplankton were collected during January and February in paired day-night, depth-stratified tows through the mesopelagic zone along the WAP from 2009-2017, as well as in day and night epipelagic net tows from 1993-2017. The copepod Metridia gerlachei, salp Salpa thompsoni, pteropod …