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Full-Text Articles in Life Sciences

A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont Jan 2024

A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont

Regis University Student Publications (comprehensive collection)

The wildlife of Costa Rica has experienced various anthropogenic threats over the last century including climate change and agricultural expansion. The mantled howler monkey (Alloutta palliata), Central American spider monkey (Ateles geoffroyi), white-faced capuchin (Cebus imitator), and the Central American squirrel monkey (Saimiri oerstedii) are Costa Rica’s native primates that face several anthropogenic threats such as deforestation for agriculture and climate change. In response to increased threats to its four native species of non-human primates, Costa Rica has implemented effective governmental conservation tactics such as the Payments for Environmental Services program, ecotourism …


Forest Management In A Changing Climate: Integrating Social And Biopysical Sciences To Inform Adaptive Responses To Future Uncertainty, Peter Breigenzer Dec 2023

Forest Management In A Changing Climate: Integrating Social And Biopysical Sciences To Inform Adaptive Responses To Future Uncertainty, Peter Breigenzer

Electronic Theses and Dissertations

Forests provide numerous ecological and socio-economic benefits, yet climate change is creating novel and extreme conditions that threaten forests and disrupt traditional management practices. To address future uncertainty about how to manage forests amid a rapidly changing climate, researchers have developed adaptive management strategies that move away from using historical ecological baselines as management goals. However, despite increases in adaptive forest management frameworks, there are still concerns that private woodland owners (PWOs; also known as family forest owners or non-industrial private landowners) are not adopting beneficial practices. Additionally, since tree canopies often buffer understory microclimates (i.e., fine scale variation in …


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 …


Improving The Land Trust Model’S Impact On Environmental Conservation In Northern California, Peter Talbot Jun 2023

Improving The Land Trust Model’S Impact On Environmental Conservation In Northern California, Peter Talbot

Master's Projects and Capstones

For years, the land trust sector of California and much of the United States has operated with a dollars and acres mentality that has prioritized fundraising as a result of acreage protected. Within California, nearly 5.8 million acres of land have been protected by 132 land trusts throughout the state. To accommodate for the diverse cross-section of land and the many needs of the population, land trusts take on numerous shapes and sizes. A unique aspect of this diversity is the rich agricultural and natural spaces found throughout the state. This mix of land and variety of land uses has …


Pasturelands As Natural Climate Solutions: A Socioecological Study Of Tree Carbon And Beef Production Trade-Offs, Bela Starinchak May 2023

Pasturelands As Natural Climate Solutions: A Socioecological Study Of Tree Carbon And Beef Production Trade-Offs, Bela Starinchak

Masters Theses, 2020-current

Forest restoration is the most effective natural climate solution, with the potential to sequester 37% of the carbon dioxide (CO2) needed to reach the Paris climate mitigation goal. Cattle pastures offer an underutilized opportunity to increase global forest restoration efforts, improve biodiversity, and maximize carbon storage through the adoption of management strategies that prioritize the incorporation of trees into pasturelands. However, remote estimations of tree carbon storage in pastoral systems have never been field-verified and their accuracy is unclear. Furthermore, the effect of increased trees on cattle production is understudied across biomes. Lastly, the restoration potential of these …


Effects Of Climate Change And Landscape-Scale Forest Management On Avian Communities, Abundance, And Nest Success In The Appalachian Mountains, Hannah L. Clipp Jan 2023

Effects Of Climate Change And Landscape-Scale Forest Management On Avian Communities, Abundance, And Nest Success In The Appalachian Mountains, Hannah L. Clipp

Graduate Theses, Dissertations, and Problem Reports

Birds are integral components of ecosystems and account for billions of dollars in tangible benefits to humans. As such, recent continental declines of bird species have ecological and economic consequences, providing the impetus for my dissertation research. I identified knowledge gaps and proposed novel questions about how birds in the Appalachian Mountains are influenced by changing environmental conditions due to climate change and forest management. The Appalachian Mountains encompass an important biogeographical region with high conservation value due to its myriad habitats and corresponding bird species diversity. Thus, there is a critical need to evaluate the effects of shifting climate …


Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson Jan 2023

Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson

Scripps Senior Theses

We are experiencing a climate crisis that must be confronted with strategic mitigation. Pomona College contributes to the climate crisis through its emissions for which there is a baseline record. However there is no baseline record of the climate mitigation currently performed by the trees on Pomona’s campus through carbon storage. This study seeks to determine a current baseline quantity of carbon stored and sequestrated by Pomona’s trees as well as possible courses of climate mitigation for Pomona College to take. Initial information gathering was conducted through interviews with several stakeholders. This study was conducted using data collected prior to …


Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh Aug 2022

Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh

Masters Theses

The Congo Basin Forest harbors a rich diversity of epiphytic communities, with the Orchidaceae alone making up more than 50% of all epiphytes in the region. Despite the huge diversity of epiphytes, many species, including epiphytic orchids, are at risk to a diverse array of threats. Climate change for instance poses severe threats to epiphytic orchids due to elevated temperatures, prolonged periods of droughts, as well as reduced rainfall across the Congo Basin Forest. In this study, we used ecological niche modeling and GIS techniques to identify spatial patterns of species richness, potential future climate refugia, and novel climatic suitability …


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 …


Common Garden Study Reveals Frost-Tolerant, Generalist Northern Seed Sources Are Best Suited To Expand Range Of Quercus Rubra, Emily Lindback Jan 2022

Common Garden Study Reveals Frost-Tolerant, Generalist Northern Seed Sources Are Best Suited To Expand Range Of Quercus Rubra, Emily Lindback

Dissertations, Master's Theses and Master's Reports

Climate change is shifting the potential suitable range of northern red oak (Quercus rubra L.) faster than it can migrate, creating an adaptation lag. Quercus rubra is prominent in eastern North American forests and important for its carbon sequestration, ecological roles, and economic significance. Our study addresses which populations of Q. rubra are best suited for climatic conditions at the northern and central range limits. Our findings can inform forestry management policies such as assisted migration, where species are transferred within their native range to mitigate the effects of climate change. We planted over 800 Q. rubra seedlings …


Modeling Hydrochemical And Vegetation Responses Of High-Elevation Forested Watersheds To Future Climate And Atmospheric Deposition Changes In The Southeastern U.S., Hailong Huang May 2021

Modeling Hydrochemical And Vegetation Responses Of High-Elevation Forested Watersheds To Future Climate And Atmospheric Deposition Changes In The Southeastern U.S., Hailong Huang

Dissertations

Changes in climate and atmospheric acidic deposition alter biogeochemical cycles in forested ecosystems. I investigated the responses of vegetation, soil, and hydro-related processes to changes in climate and acidic deposition at five high-elevation forests in the southeastern U.S. using a biogeochemical model - PnET-BGC model. I focused on change-points and thresholds concepts that were less studied in forest ecosystems as well as seasonal variability of responses and extreme events. I applied principal component analysis (PCA) to reduce the dimensionality of data. I developed a Bayesian multi-level model to derive key biogeochemical variables response to temperature and precipitation (local) and latitude …


Effects Of Prescribed Fire On Drought Resistance And Recovery In Mixed Conifer Forests Of Lassen Volcanic National Park, California, Zachary J. Wenderott Jan 2021

Effects Of Prescribed Fire On Drought Resistance And Recovery In Mixed Conifer Forests Of Lassen Volcanic National Park, California, Zachary J. Wenderott

Cal Poly Humboldt theses and projects

Forests throughout much of the western United States are experiencing increasing climatic variability, often resulting in decreased forest productivity and elevated likelihood of tree mortality. Severe drought, such California’s recent 2012-2015 drought, are projected to increase in intensity, frequency, and severity throughout much of this region in coming years. Forest management has long relied on prescribed fire and mechanical thinning to reduce fuel loads and ameliorate potential fire hazards. These treatments may also have the ability to reduce stand density, alleviate competitive pressures, and allow residual trees access to critical resources during periods of extreme stress. Utilizing a long-term National …


The Future Of Maine's Forests Under Alternative Socioeconomic, Climate And Conservation Pathways, Jianheng Zhao Dec 2020

The Future Of Maine's Forests Under Alternative Socioeconomic, Climate And Conservation Pathways, Jianheng Zhao

Electronic Theses and Dissertations

Maine is a historically important timber supply region in North America and understanding the potential change in forestlands and their product industries affected by climate change and various socio-economic conditions can better improve the forest healthy and sustain a sustainable product industry. A statistical harvest choice model for the state of Maine was developed in chapter 1. It was estimated using a multinomial logit model of two products, under varying management intensities, and ownership classifications across varying market conditions. Results indicate that stumpage prices have a significant effect on forest landowners' harvest decisions and that the expansion of conservation land …


Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes Nov 2020

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …


Interacting Effects Of Climate And Biotic Factors On Mesocarnivore Distribution And Snowshoe Hare Demography Along The Boreal-Temperate Ecotone, Alexej P. Siren Jul 2020

Interacting Effects Of Climate And Biotic Factors On Mesocarnivore Distribution And Snowshoe Hare Demography Along The Boreal-Temperate Ecotone, Alexej P. Siren

Doctoral Dissertations

The motivation of my dissertation research was to understand the influence of climate and biotic factors on range limits with a focus on winter-adapted species, including the Canada lynx (Lynx canadensis), American marten (Martes americana), and snowshoe hare (Lepus americanus). I investigated range dynamics along the boreal-temperate ecotone of the northeastern US. Through an integrative literature review, I developed a theoretical framework building from existing thinking on range limits and ecological theory. I used this theory for my second chapter to evaluate direct and indirect causes of carnivore range limits in the northeastern US, …


A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle May 2020

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle

Master's Projects and Capstones

Wildfires in the mixed conifer forests of California’s Sierra Nevada have been a common and natural disturbance for thousands of years, historically occurring every 3 to 30 years. The flora and fauna of the mixed conifer forest have evolved to depend on low to moderate severity wildfires for reproduction, foraging, and habitat. However, the Sierra Nevada has experienced dramatic environmental changes over the past ~150 years as a result of three main factors: wildfire suppression, climate change, and habitat loss. Because of the threat wildfires pose to human lives, property and timber harvest, they have been suppressed to an extent …


Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney Jul 2019

Ecological Considerations And Application Of Urban Tree Selection In Massachusetts, Ashley Mcelhinney

Masters Theses

Trees provide countless environmental, economic, and societal benefits to the urban environment, and may become increasingly important to maintaining environmental quality and human well-being in the face of increasing urbanization and climate change. However, trees in these urban areas are rapidly diminishing across the United States. Much of this loss can be prevented with proper planning and management, focused on selecting tree species that are both well-suited to the area’s growing conditions and able to survive the many stress factors in an urban setting. Choosing which tree species to plant in Massachusetts is especially challenging considering the lack of resources …


Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen Jan 2019

Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen

Graduate Theses, Dissertations, and Problem Reports

Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …


Reexamining The Utility Of Existing Climate Adaptation Frameworks Through Application On A Northern Forest, Alexander Rice Jan 2019

Reexamining The Utility Of Existing Climate Adaptation Frameworks Through Application On A Northern Forest, Alexander Rice

Dissertations, Master's Theses and Master's Reports

A review of the literature reveals the strengths and limitations of various climate adaptation frameworks and illuminates a general path by which a type of adaptation can be achieved. A number of useful frameworks exist but the number of independent case studies demonstrating the adaptation process in a detailed manner is much more limited. Additionally, components of the various adaptation processes can often seem vague and concepts such as adaptability ill-defined. For land managers approaching climate adaptation independently can be difficult, particularly in the areas of goal creation and vulnerability assessment. Within frameworks where user-defined adaptation goals dictate whether or …


Drivers Of Post-Fire Vascular Plant Regeneration In The Conifer-Dominated Boreal Forest Of Southern Northwest Territories, Alison White Jan 2018

Drivers Of Post-Fire Vascular Plant Regeneration In The Conifer-Dominated Boreal Forest Of Southern Northwest Territories, Alison White

Theses and Dissertations (Comprehensive)

In recent years, climate warming has led to an increase in the severity and frequency of naturally occurring fires in boreal ecosystems globally. In 2014, an unprecedented 3.4 million hectares of boreal forest burned in the Northwest Territories (NWT). While much research has focused on post-fire succession of serotinous tree species such as Picea mariana (black spruce) and Pinus banksiana (jack pine), the understory community of vascular plants play an important role in ecosystem functioning but less is known about the response of this component of the system to changing fire regimes. Regeneration strategies such as the ability to resprout …


Estimating The Range Shift And Harvesting Intensity Of Junipers In Bhutan (Eastern Himalaya), Rinchen Namgay Nov 2017

Estimating The Range Shift And Harvesting Intensity Of Junipers In Bhutan (Eastern Himalaya), Rinchen Namgay

Theses

The authors of more than 97% of the scientific publications on climate change agree that global temperature has increased in the last six decades and is caused by human beings via emission of greenhouse gases in the atmosphere. This phenomenon has altered natural ecosystem functions, causing many species to shift to a more suitable habitat. Throughout the world, because of recent climate warming, many forms of range shift associated with climate warming has occurred. While animals can move as warming happens, plants being stationary organisms cannot move, so the difference in the distribution of different plant life stages is an …


Modeling Historical And Future Range Of Variability Scenarios In The Yuba River Watershed, Tahoe National Forest, California, Maritza Mallek Jul 2016

Modeling Historical And Future Range Of Variability Scenarios In The Yuba River Watershed, Tahoe National Forest, California, Maritza Mallek

Masters Theses

In California's northern Sierra Nevada mountains, the fire-dependent processes of forest ecosystems have been interrupted and altered by human land use and fire suppression. U.S. Forest Service policy directs land managers to plan for a future that includes multiple use and the restoration of resilient ecosystems. Planning decisions are to be informed by an analysis of the range of variability of ecological processes at multiple scales. Current climate trends in the northern Sierra are of increasing temperatures, increased precipitation, and earlier snowmelt, as well as changes to the frequency and duration of drought. These climate changes have and continue to …


Tree Growth Dynamics, Fire History, And Fire-Climate Relationships In Pine Rocklands Of The Florida Keys, U.S.A., Grant Logan Harley May 2012

Tree Growth Dynamics, Fire History, And Fire-Climate Relationships In Pine Rocklands Of The Florida Keys, U.S.A., Grant Logan Harley

Doctoral Dissertations

Pine rocklands are globally endangered, fire-maintained communities currently restricted to small habitat areas in southern Florida, Cuba, and the Bahamas. The purpose of this dissertation research was to identify the long-term ecological disturbance regimes and climatic trends responsible for the persistence of pine rocklands, and examine how human-induced changes during the 20th century contributed to decline of these communities. This research applied techniques of dendrochronology in extreme southern Florida, in a subtropical region where tree‐ring science has never been applied, to increase the understanding of how anthropogenic and natural disturbance events have decreased the spatial distribution of South Florida …