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Full-Text Articles in Life Sciences
A Conservation Model: Costa Rican Conservation Strategies Effectively Preserve Their Threatened Primates, Ryan Belmont
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 …
Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi
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
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 …
Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo
Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo
Cal Poly Humboldt theses and projects
The 2012-2016 California drought was the most severe in the state’s recorded history, contributing to the death of millions of trees. While the effects of this drought on forests are relatively well studied in the central and southern Sierra Nevada, less is known about its effects on the heavily timbered and diverse forests of northern California. Through sampling 54 0.25 ha plots in northern California, this study compared tree mortality and regeneration patterns before, during, and after California’s most recent record-setting drought. This study evaluated 1) the influence of habitat and competitive covariates on mortality and regeneration trends using ridge …
Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen
Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen
Electronic Theses and Dissertations
Climate change is expected to lead to novel drought conditions in the Northeastern United States. Therefore, experimental studies that mimic these conditions are crucial to understand the potential impact on forests. Further, recent large scale dendrochronological studies suggest that spring and summer droughts may immediately impact tree growth while fall droughts may cause delayed impacts on growth the following growing season. Therefore, in this study, we investigated the impacts of six-week-long spring, summer, and fall droughts on the physiology and intra-annual growth on 288 saplings of six tree species native to the Northeastern United States. These species (deciduous broadleaf angiosperms, …
The Ecological Resilience Of A Tropical Montane Pine Forest To Droughts, Fire, And Hurricane Disturbance, Daniel Erland Brugger Swann
The Ecological Resilience Of A Tropical Montane Pine Forest To Droughts, Fire, And Hurricane Disturbance, Daniel Erland Brugger Swann
Electronic Theses and Dissertations
Owing to the geographic isolation and unique climatic conditions which occur in tropical montane forests (TMFs), these systems are highly sensitive to changes in both climate and disturbance. Therefore, as ongoing climate change alters disturbance regimes – potentially facilitating multiple disturbance interactions much greater than that of isolated disturbances – TMFs may be shifted to alternate stable states. However, study of TMF resilience is essentially unknown given the lack of long-term studies in these systems. We address the resiliency of the tropical montane pine forests of the Cordillera Central, Dominican Republic using long-term climate records, remeasured vegetation data, and reconstructed …
Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes
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 …
Warming Up: Climate Change Related Shifts Of Mycorrhizal Fungal Communities In High Latitude Ecosystems, Megan Rae Devan
Warming Up: Climate Change Related Shifts Of Mycorrhizal Fungal Communities In High Latitude Ecosystems, Megan Rae Devan
Biology ETDs
This dissertation examines how climate change affects mycorrhizal fungal communities in boreal and arctic ecosystems. In chapter one, I revealed that increases in fire severity and related increases in deciduous tree dominance result in greater Ascomycota relative abundance (RA) and subsequent declines in Basidiomycota RA. In chapter two I analyzed the effects of post-fire mycorrhizal fungal communites on host growth. There were trends at the fungal genus level that were largely reflected at the guild level across all hosts; however, there were some fungal genera that had the opposite effect on different host species. In chapter three, I found host …
Growth Dynamics Of Black Spruce (Picea Mariana) Across Northwestern North America, Anastasia E. Sniderhan
Growth Dynamics Of Black Spruce (Picea Mariana) Across Northwestern North America, Anastasia E. Sniderhan
Theses and Dissertations (Comprehensive)
The impacts of climate change have been widely documented around the world. One of the most rapidly changing areas is the boreal forest of North America. The extent of change has been such that there have been shifts in long-standing climate-growth relationships in many boreal tree species; while the growth of many of these high-latitude forests were formerly limited by temperature, warming has increased the evapotranspirative demands such that there is widespread drought stress limiting productivity in the boreal forest. With the importance of the boreal forest as a global carbon sink, it is imperative to understand the extent of …
Drivers Of Post-Fire Vascular Plant Regeneration In The Conifer-Dominated Boreal Forest Of Southern Northwest Territories, Alison White
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 …
Elevated Temperature And Co2 Concentrations Affect Carbon Flux In Two Boreal Conifers, Sasha Madhavji
Elevated Temperature And Co2 Concentrations Affect Carbon Flux In Two Boreal Conifers, Sasha Madhavji
Electronic Thesis and Dissertation Repository
Elevated temperatures and CO2 will alter carbon flux in two dominant boreal tree species Picea mariana (black spruce) and Larix laricina (tamarack). Trees were grown in three temperature treatments (ambient, ambient +4 °C, and ambient +8 °C) at either 400 ppm or 750 ppm CO2, to simulate climate conditions between now and the year 2100. Spruce acclimated to increasing temperature detractively; warming scenarios reduced spruce net carbon gain. Tamarack maintained comparable levels of net photosynthesis (Anet) across warming treatments and both species acclimated respiration (Rdark) with increasing growth temperature. Elevated CO2-grown …