Open Access. Powered by Scholars. Published by Universities.®

Forest Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Plant Biology

PDF

2021

Institution
Keyword
Publication
Publication Type

Articles 1 - 11 of 11

Full-Text Articles in Forest Sciences

Functional Strategies Of Tree Fine-Roots In Relation To The Soil Environment And Microbiome: Variaiton In Root Morphology, Tissue Chemistry And Physiology, James Aaron Hogan Nov 2021

Functional Strategies Of Tree Fine-Roots In Relation To The Soil Environment And Microbiome: Variaiton In Root Morphology, Tissue Chemistry And Physiology, James Aaron Hogan

FIU Electronic Theses and Dissertations

Tree root systems have evolved multidimensional functioning, specializing in water and nutrient acquisition via different strategies. Root functional strategies vary among tree species and are adapted to the abiotic and biotic soil environment. This dissertation explores how three facets of root system functional strategies – morphology and chemistry, biotic associations with fungi, and respiration rates – vary within and among tree species along environmental gradients. Chapter one examines how root system morphology varies with forest succession and soil environment in a tropical forest of Hainan, China, finding that root systems had larger diameters and fewer root tips in the younger …


Tree Responses To Moderate And Extreme Drought In The Northeastern United States, Ruth A. Van Kampen Aug 2021

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, …


Hawai‘I Forest Review: Synthesizing The Ecology, Evolution, And Conservation Of A Model System, Kasey E. Barton, Andrea Westerband, Rebecca Ostertag, Elizabeth Stacy, Kawika Winter, Donald R. Drake, Lucas Berio Fortini, Creighton M. Litton, Susan Cordell, Paul Krushelnycky, Kapua Kawelo, Kealoha Feliciano, Gordon Bennett, Tiffany Knight Aug 2021

Hawai‘I Forest Review: Synthesizing The Ecology, Evolution, And Conservation Of A Model System, Kasey E. Barton, Andrea Westerband, Rebecca Ostertag, Elizabeth Stacy, Kawika Winter, Donald R. Drake, Lucas Berio Fortini, Creighton M. Litton, Susan Cordell, Paul Krushelnycky, Kapua Kawelo, Kealoha Feliciano, Gordon Bennett, Tiffany Knight

Life Sciences Faculty Research

As the most remote archipelago in the world, the Hawaiian Islands are home to a highly endemic and disharmonic biota that has fascinated biologists for centuries. Forests are the dominant terrestrial biome in Hawai‘i, spanning complex, heterogeneous climates across substrates that vary tremendously in age, soil structure, and nutrient availability. Species richness is low in Hawaiian forests compared to other tropical forests, as a consequence of dispersal limitation from continents and adaptive radiations in only some lineages, and forests are dominated by the widespread Metrosideros species complex. Low species richness provides a relatively tractable model system for studies of community …


Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker May 2021

Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Phytophthora ramorum is the causal agent of Sudden Oak death (SOD), ramorum dieback and ramorum leaf blight which affect both forest environments and nurseries. This oomycete pathogen has had a huge economic impact on the nursery and lumber industry. Forests in California have experienced substantial mortality of oaks affecting the forest dynamics and diversity. Our research investigates four native species and two ornamental cultivars of plants, which belong to the genus Arctostaphylos (manzanita) and are considered to be new hosts for P. ramorum in the chaparral ecosystem of California. Symptom expression and transmission rates were analyzed on Arctostaphylos glauca, …


Salicylic Acid Response To Simulated Herbivory In Geographically Distinct T. Heterophylla And H. Discolor Populations, Amy E. Castle May 2021

Salicylic Acid Response To Simulated Herbivory In Geographically Distinct T. Heterophylla And H. Discolor Populations, Amy E. Castle

Honors Projects

It is commonly known that plants may produce salicylic acid as a chemical defense response to wounding, although the phenomenon has usually been observed with regard to insect herbivory. Stem and leaf tissue of two species, Tsuga heterophylla and Holodiscus discolor, which are often eaten by deer, were extracted in methanol and analyzed by HPLC to quantify salicylic acid concentration in experimentally wounded or control samples. No salicylic acid response was detectable in T. heterophylla, suggesting it is a less useful candidate species for future study. Some but not all H. discolorsamples had a measurable salicylic acid …


Sensitivity And Threshold Dynamics Of Pinus Strobus And Quercus Spp. In Response To Experimental And Naturally-Occurring Severe Droughts, Heidi Asbjornsen, Cameron D. Mcintire, Matthew A. Vadeboncoeur, Katie A. Jennings, Adam P. Coble, Z. Carter Berry May 2021

Sensitivity And Threshold Dynamics Of Pinus Strobus And Quercus Spp. In Response To Experimental And Naturally-Occurring Severe Droughts, Heidi Asbjornsen, Cameron D. Mcintire, Matthew A. Vadeboncoeur, Katie A. Jennings, Adam P. Coble, Z. Carter Berry

Earth Systems Research Center

Increased drought frequency and severity are a pervasive global threat, yet the capacity of mesic temperate forests to maintain resilience in response to drought remains poorly understood. We deployed a throughfall removal experiment to simulate a once in a century drought in New Hampshire, USA, which coupled with the region-wide 2016 drought, intensified moisture stress beyond that experienced in the lifetimes of our study trees. To assess the sensitivity and threshold dynamics of two dominant northeastern tree genera (Quercus and Pinus), we monitored sap flux density (Js), leaf water potential and gas exchange, growth, and intrinsic water use efficiency (iWUE) …


Picking Up Where The Tmdl Leaves Off: Using The Partnership Wild And Scenic River Framework For Collaborative River Restoration, Alan R. Hunt, Meiyin Wu, Tsung-Ta David Hsu, Nancy Roberts-Lawler, Jessica T. Miller, Alessandra Rossi, Lee Lee Feb 2021

Picking Up Where The Tmdl Leaves Off: Using The Partnership Wild And Scenic River Framework For Collaborative River Restoration, Alan R. Hunt, Meiyin Wu, Tsung-Ta David Hsu, Nancy Roberts-Lawler, Jessica T. Miller, Alessandra Rossi, Lee Lee

Department of Biology Faculty Scholarship and Creative Works

The National Wild and Scenic Rivers Act protects less than ¼ of a percent of the United States’ river miles, focusing on free-flowing rivers of good water quality with outstandingly remarkable values for recreation, scenery, and other unique river attributes. It predates the enactment of the Clean Water Act, yet includes a clear anti-degradation principle, that pollution should be reduced and eliminated on designated rivers, in cooperation with the federal Environmental Protection Agency and state pollution control agencies. However, the federal Clean Water Act lacks a clear management framework for implementing restoration activities to reduce non-point source pollution, of which …


The Impacts Of Imazapic On Garlic Mustard And Non-Target Forest Floor Vegetation In Central Kentucky’S Hardwood Forests, Pavan Kumar Podapati Jan 2021

The Impacts Of Imazapic On Garlic Mustard And Non-Target Forest Floor Vegetation In Central Kentucky’S Hardwood Forests, Pavan Kumar Podapati

Theses and Dissertations--Forestry and Natural Resources

Alliaria petiolata is an invasive biennial herb that poses a substantial threat to various ecosystems across the United States. Imazapic herbicide can control A. petiolata infestations, but there is limited peer-reviewed data on impacts of pre-emergent imazapic spraying to forest floor communities. This research examined the impacts of pre-emergent imazapic (0.84 kg/ha) with Pentra-Bark® surfactant on ground cover of A. petiolata and the spring perennials Claytonia virginica and Erigenia bulbosa. Experimental populations in randomized blocks within two forest stands in central Kentucky received the following treatments at 0.84 kg ai/ha: imazapic with Pentra-Bark®, glyphosate with Pentra-Bark®, Pentra-Bark® alone, and …


Environmental Controls On The Terrestrial Water Cycle In Forested Mountain Ecosystems., Luis Andrés Guillén Jan 2021

Environmental Controls On The Terrestrial Water Cycle In Forested Mountain Ecosystems., Luis Andrés Guillén

Graduate Theses, Dissertations, and Problem Reports

Water is a key resource to natural ecosystems and human societies alike, and the water cycle is fundamentally linked to the climate and the characteristics of catchments. However, the challenges posed by environmental change makes it imperative to understand how the water cycle is affected by biotic and abiotic factors, in particular, in areas that are crucial sources of water like forested headwater catchments. Therefore, this doctoral dissertation aims to advance the knowledge on the dynamics between climate, vegetation and landscape that determine the water balance of forested mountain ecosystems. This document presents five chapters, an introductory chapter, three standalone …


Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff Jan 2021

Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana) woodlands across their range are becoming increasingly threatened by encroaching Douglas-fir encroachment (Pseudotsuga menziesii) as a result of fire exclusion. Using water potential (Ψ), stomatal conductance (gs), xylem water stable isotopes (dD), and three metrics of biodiversity, this study investigates the effects of conifer encroachment and removal at the ecosystem-scale. The study was set in an Oregon white oak woodland in northern California and compared three levels of encroachment before and after conifer removal. Findings indicate that heavily encroached stands have the least amount of water stress and gas …


Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer Jan 2021

Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer

Theses and Dissertations (Comprehensive)

Climate change is altering the boreal wildfire regime through increases in the extent and severity of burning and reductions in fire return intervals. These changes can alter the regeneration trajectory of canopy species and ground vegetation, with implications for wildlife habitat. There is some uncertainty about the timelines of when different animal species will use burned areas as their preferred forage taxa recover following fire, and how such recovery is mediated by environmental factors. Here, we aim to address these knowledge gaps through the following questions: 1) What are the main forage types consumed by boreal wildlife and how much …