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Full-Text Articles in Life Sciences

Insights Into The Challenges Posed By Climate Change And Land Competition To Brazil’S Midwest Pulpwood Market, Roberto Hajime Sant Anna Kimura Dec 2023

Insights Into The Challenges Posed By Climate Change And Land Competition To Brazil’S Midwest Pulpwood Market, Roberto Hajime Sant Anna Kimura

Theses and Dissertations

I investigated the effect of climate change in one of the few expanding markets in the world in Brazil. In the last decades the demand for pulpwood increased from zero to 11 million tons, leading to an expansion of 700 thousand hectares of Eucalyptus plantation. In 2024, a new mill will start operating increasing the consumption of wood fiber by 8.2 million tons (+49%). I used mathematical programming to investigate how different scenarios of productivity and land will affect the market. My results showed that around 946,000 hectares (+124%) of additional timberland will be necessary in the upcoming decades. The …


Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi May 2022

Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi

Theses and Dissertations

Anticipated climate change and increasing wood demand require dependable diameter growth models for adaptive forest management. We used a mixed-effects modeling approach with Forest Inventory and Analysis (FIA) data to fit diameter growth models for loblolly pine, other softwood species (slash pine, shortleaf pine, and longleaf pine), sweetgum, and other hardwood (southern red oak, red maple, and water oak) species. Climatic variables coupled with individual tree attributes and competition factors improved climate insensitive models. Growth of loblolly pine and sweetgum was positively correlated with mean temperature of the coldest month. Mean temperature of the warmest month negatively influenced diameter growth …


An Analysis Of The Effects Of Temperature And Other Environmental Factors On Microorganismal Productivity Within Aquatic Ecosystems Using Long-Term Data From Various Lter And Ilter Sites, Andrew Dorbu May 2022

An Analysis Of The Effects Of Temperature And Other Environmental Factors On Microorganismal Productivity Within Aquatic Ecosystems Using Long-Term Data From Various Lter And Ilter Sites, Andrew Dorbu

Theses and Dissertations

Global climate change is a phenomenon resulting in more extreme weather patterns and species diversity loss. In this study, I explore the impacts of climate change on regional patterns of microbial productivity. Variation in microbial productivity was explained using temperature, salinity, and dissolved oxygen as predictors in regression models with data from the LTER and iLTER network of sites that ranged from the poles to the equator. I found a positive relationship between temperature and productivity. Antarctica and Arctic sites exhibited the strongest positive relationships supporting prior research demonstrating temperature as one of the driving forces of productivity change in …


The Potential Impact Of Climate Change On The Distributions Of Eleutherodactylus Cystignathoides And E. Planirostris (Anura: Eleutherodactylidae), Rebecca T. Chastain May 2022

The Potential Impact Of Climate Change On The Distributions Of Eleutherodactylus Cystignathoides And E. Planirostris (Anura: Eleutherodactylidae), Rebecca T. Chastain

Theses and Dissertations

Climate change is inducing changes in the distributions of many species, causing range shifts and habitat loss as well as facilitating invasions. It is a broad contributor to global amphibian decline, already causing mass extinctions and extirpations of amphibian populations, a phenomenon which is expected to continue. The understudied direct-developing frog Eleutherodactylus cystignathoides is a notable outlier, having rapidly expanded its distribution in recent years. This is of particular interest given that other eleutherodactylids, such as E. coqui and E. planirostris, have already shown propensity for rapid dispersal and invasion. Originally found in the southernmost tip of …


Climate Change, Increased Wildfire Frequency, And Rodent-Exclusion Create Opportunities For Exotic Grass Invasion And Alter The Timing And Availability Of Soil Water, Joshua Clark Gilman Dec 2020

Climate Change, Increased Wildfire Frequency, And Rodent-Exclusion Create Opportunities For Exotic Grass Invasion And Alter The Timing And Availability Of Soil Water, Joshua Clark Gilman

Theses and Dissertations

In deserts, global environmental changes, plant community structure, and soil water availability form a complex relationship characterized by direct and indirect relationships and feedbacks. Plant community structure is affected by the establishment and spread of invasive grasses, which form a positive feedback with wildfire. Plant community structure is also controlled by top-down trophic interactions by small-mammals and climate change, which alters the timing and amount of soil water. In deserts, soil water availability mediates the effects of global environmental changes and trophic interactions on plant community structure because it is the limiting resource for plant growth. In order to predict …


Understanding The Influence Of Changing Climate On Mycotoxin Contamination Of Food And Indoor Fungi-Mediated Respiratory Illness, Mayomi Helen Omebeyinje Jul 2020

Understanding The Influence Of Changing Climate On Mycotoxin Contamination Of Food And Indoor Fungi-Mediated Respiratory Illness, Mayomi Helen Omebeyinje

Theses and Dissertations

Over the years, climate change has been a major core issue in public and environmental health. The World Health Organization (WHO) estimated that about 250,000 additional death per year would be attributed to climate change between 2030 and 2050 if this situation persists. Since our population depends on (but not limited to) the availability of clean water, good air quality, and exposure to environmental hazards/pathogens, the overall health impact caused by climate change is likely to be overwhelming in the nearest future. This dissertation explored the influence of climate change on fungi diseases and pathogenesis after severe weather conditions (hurricanes …


Salt Marsh Health And Biomass Responses To A Changing Environment, Gwen Joelle Miller Oct 2019

Salt Marsh Health And Biomass Responses To A Changing Environment, Gwen Joelle Miller

Theses and Dissertations

Coastal salt marshes are important ecosystems not only for their aesthetic beauty but also for their ecosystem services that they provide including improving water quality, providing protection from storm surges and hurricanes, and carbon sequestration. With climate change, including drought, warmer temperatures and sea-level rise, these systems are going to be impacted. Understanding how salt marshes will respond, or already have responded, to climate change will help us be better prepared for the future. By scripting a model to project how marshes may migrate with sea-level rise, I discover that salt marshes within Beaufort and Jasper counties, South Carolina will …


The Effects Of Climate Change On The Ecotoxicology Of Contaminants Of Emerging Concern: Flame Retardants, Contemporary Use Pesticides And Pharmaceuticals Personal Care Products On The Estuarine Grass Shrimp, Palaemontes Pugio, Rajaa Nouri Al-Yassein Jul 2019

The Effects Of Climate Change On The Ecotoxicology Of Contaminants Of Emerging Concern: Flame Retardants, Contemporary Use Pesticides And Pharmaceuticals Personal Care Products On The Estuarine Grass Shrimp, Palaemontes Pugio, Rajaa Nouri Al-Yassein

Theses and Dissertations

Global Climate Change may adversely affect the environment, increasing water temperature and altered salinity which may affect the toxicity of both legacy pollutants and Contaminants of Emerging Concern (CECs). Acute, 96 hour toxicity tests with adult grass shrimp (Palaemonetes pugio) assessed the effects of CECs (Polybrominated Diphenyl Esther (PBDE) – 47, ibuprofen, bifenthrin, triclosan, and bifenthrin/triclosan mixtures) under Standard Conditions (20°C, 20psu) and different Climate Change Conditions (30°C, and/or35psu) In addition, the grass shrimp microbiome (e.g. Vibrio bacteria) were assessed following acute triclosan exposures at the Maximum Exposure Concentration (MECs) and Minimum Inhibitory Concentration (MICs) under standard conditions. …


Of Fire, Mammals, And Rain: Mechanisms Of Plant Invasions, Tara Boyce Bishop Jul 2019

Of Fire, Mammals, And Rain: Mechanisms Of Plant Invasions, Tara Boyce Bishop

Theses and Dissertations

Biological invasions are driving environmental state changes on a global scale. Exotic plant species must be successful at passing several abiotic and biotic filters to establish and disrupt the native plant community assembly. Understanding where exotic plants are on a regional scale and being able to characterize how exotic plants are generally interacting with their environment is crucial information for exotic species management (chapter 1). In the western United States human-related activities are augmenting the spread of exotic plant species by increasing the ignitions of wildfire. Wildfire can lead to nutrient pulses through the removal of intact native communities and …


Understanding Community And Ecophysiology Of Plant Species On The Colorado Plateau, Hannah Elizabeth Yokum Dec 2017

Understanding Community And Ecophysiology Of Plant Species On The Colorado Plateau, Hannah Elizabeth Yokum

Theses and Dissertations

The intensification of aridity due to anthropogenic climate change is likely to have a large impact on the growth and survival of plant species in the southwestern U.S. where species are already vulnerable to high temperatures and limited precipitation. Global climate change impacts plants through a rising temperature effect, CO2 effect, and land management. In order to forecast the impacts of global climate change, it is necessary to know the current conditions and create a baseline for future comparisons and to understand the factors and players that will affect what happens in the future. The objective of Chapter 1 is …


Understanding Community And Ecophysiology Of Plant Species On The Colorado Plateau, Hannah Elizabeth Yokum Dec 2017

Understanding Community And Ecophysiology Of Plant Species On The Colorado Plateau, Hannah Elizabeth Yokum

Theses and Dissertations

The intensification of aridity due to anthropogenic climate change is likely to have a large impact on the growth and survival of plant species in the southwestern U.S. where species are already vulnerable to high temperatures and limited precipitation. Global climate change impacts plants through a rising temperature effect, CO2 effect, and land management. In order to forecast the impacts of global climate change, it is necessary to know the current conditions and create a baseline for future comparisons and to understand the factors and players that will affect what happens in the future. The objective of Chapter 1 is …


Vulnerable Species In A Changing Climate: The Genomic Response Of Antarctic Notothenioid Fishes To Predicted Oceanic Conditions As A Model Of Physiological Plasticity And Adaptive Capability, Troy James Huth Dec 2015

Vulnerable Species In A Changing Climate: The Genomic Response Of Antarctic Notothenioid Fishes To Predicted Oceanic Conditions As A Model Of Physiological Plasticity And Adaptive Capability, Troy James Huth

Theses and Dissertations

In its fifth report in 2014 the IPCC reinforced the contribution of anthropogenic CO2 to global climate change predicting widespread and significant changes to the global climate over a relatively short time scale. The polar regions, including the Southern Ocean surrounding Antarctica, were identified as ecosystems that may experience the most rapid and severe changes. As the Southern Ocean is one of the coldest and most oceanographically stable regions on earth, the endemic fauna likely have no alternative habitats available for migration. Further compounding the challenge these species will face is the substantial degree of adaptation to the extreme cold …


Environmental And Adaptive Buffers That Mediate The Response Of Subalpine Ecosystems To Environmental Change, Lafe G. Conner Jun 2015

Environmental And Adaptive Buffers That Mediate The Response Of Subalpine Ecosystems To Environmental Change, Lafe G. Conner

Theses and Dissertations

This document reports the results of 4 studies of subalpine ecosystem ecology, describing ways that spatial heterogeneity in soils and plant communities mediate ecosystem responses to environmental change. Ecosystem responses to environmental change are also mediated by regional climate patterns and interannual variability in weather. In the first chapter we report the results of an experiment to test for the mediating effects of associational resistance in a forest community that experienced wide-spread beetle kill. We found that Engelmann spruce were more likely to survive a beetle outbreak when growing in low densities (host dilution) and not through other types of …


Expanding Eco-Visualization: Sculpting Corn Production, Jennifer E. Figg Jan 2015

Expanding Eco-Visualization: Sculpting Corn Production, Jennifer E. Figg

Theses and Dissertations

This dissertation expands upon the definition of eco-visualization artwork. EV was originally defined in 2006 by Tiffany Holmes as a way to display the real time consumption statistics of key environmental resources for the goal of promoting ecological literacy. I assert that the final forms of EV artworks are not necessarily dependent on technology, and can differ in terms of media used, in that they can be sculptural, video-based, or static two-dimensional forms that communicate interpreted environmental information. There are two main categories of EV: one that is predominantly screen-based and another that employs a variety of modes of representation …


Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad Dec 2014

Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad

Theses and Dissertations

Population connectivity, particularly in open systems, is an important metric for understanding population-level processes on both ecological and evolutionary timescales. In coastal marine systems, adults are typically sedentary and dispersal occurs primarily during a larval stage when individuals are transported in ocean currents. Because coastal marine populations exist as networks of interconnected subpopulations, variation in the magnitude and extent of population connectivity can have profound effects on population dynamics and species distribution limits. Connectivity is a complex process, affected by a multitude of factors, including adult inputs and physical dispersal, which operate at multiple scales and may interact. This dissertation …


Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco Dec 2014

Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco

Theses and Dissertations

Untangling natural systems’ complexity requires understanding the mechanisms responsible for organisms’ responses to environmental change. Recently, significant advances have been made by recognizing the relevance of direct and indirect effects, which take place when multiple biotic and abiotic factors influence each other. I examined potential direct effects of environmental variables on a predator-prey interaction, as well as potential indirect effects of these variables on the interaction itself. I placed emphasis on behavioral and physiological adaptations, which would potentially contribute/modify these effects. My study system was comprised of a rocky intertidal keystone predator, the sea star Pisaster ochraceus, and its main …


Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor Dec 2014

Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor

Theses and Dissertations

The introduction and establishment of exotic species can profoundly alter ecosystems. Two exotic species drastically changing the landscape of deserts in western North America are Bromus tectorum L. and Bromus rubens L. Through the buildup of biomass and slow decomposition rates in deserts these two exotic annual grasses can alter fire regimes that change the plant and animal community dynamics in the ecosystems. To better understand the ecological mechanisms that could restrict or alter the patterns of invasive plant establishment we established a replicated full factorial experiment in the Great Basin and Mojave Desert. The combinations of factors being manipulated …


Post-Den Emergence Behavior And Den Detection Of Polar Bears (Ursus Maritimus) In Northern Alaska And The Southern Beaufort Sea, Rusty Wade Robinson Mar 2014

Post-Den Emergence Behavior And Den Detection Of Polar Bears (Ursus Maritimus) In Northern Alaska And The Southern Beaufort Sea, Rusty Wade Robinson

Theses and Dissertations

Pregnant polar bears (Ursus maritimus) construct maternal dens out of snow in the autumn where they give birth to and raise altricial young. In recent years, there has been a decrease in polar sea ice extent and thickness, which has led to changes in denning behavior. One such change in the southern Beaufort Sea (SBS) is that polar bears are selecting maternal den sites on land, rather than on unstable sea ice. This change, coupled with expanding petroleum exploration along Alaska's North Slope, heightens the likelihood of bear-human interactions at maternal den sites. The purpose of this research …


Post-Fire Soil Water Repellency: Extent, Severity And Thickness Relative To Ecological Site Characteristics Within Piñon-Juniper Woodlands, Daniel Lewis Zvirzdin Jun 2012

Post-Fire Soil Water Repellency: Extent, Severity And Thickness Relative To Ecological Site Characteristics Within Piñon-Juniper Woodlands, Daniel Lewis Zvirzdin

Theses and Dissertations

Erosion and weed dominance often limit the recovery of burned piñon-juniper woodlands. Soil water repellency (SWR) is one factor that may contribute to this by increasing overland flow and impeding seedling establishment. In spite of these effects, the extent of SWR within piñon-juniper woodlands is unknown. In this study, the extent, severity and thickness of SWR were sampled across 41 1,000 m2 plots within three 2009 Utah wildfires. Predictive models of SWR were built from ecological site characteristic data collected at each site. Across the study, SWR was found at 37% of the points sampled. SWR extent was strongly related …