Plant Biology Commons^™

Visualizing 25 Years Of Change In The Glades Oak Savanna, Zoe Fieberg

Summer Research Showcase

Oak savannas represent one of the most threatened ecosystems in Minnesota due to changing land use management, particularly absence of fire (Davis, 2001). Frequent burns kill fire-sensitive mesophytic tree species, reducing the dominance of woody understory and allowing for restoration of the oak savanna environment. The GLADES (Grid for Landscape Analysis and Demographic Study) site was established in 1988 in East Bethel, Minnesota to study the effect of frequent burning on oak savanna restoration. Through the use of standardized methods of photography, we compared canopy differences across GLADES between 2001 and 2026. Preliminary observations revealed increased canopy density and reduced …

Testing The Intermediate Disturbance Hypothesis On Anthropogenic Pressure In Central Alabama, Gavin Terrell

Theses

Biodiversity is fundamental to maintaining ecosystem structure and function globally. Prior to the late 20th century, ecological theory generally predicted that biodiversity would be highest in systems experiencing minimal disturbance. However, Joseph H. Connell challenged this view with the Intermediate Disturbance Hypothesis (IDH), which posits that species diversity peaks at intermediate levels of disturbance and declines under conditions of both low and high disturbance. Although widely cited, the applicability of the IDH to natural systems remains debated, particularly in the context of anthropogenic disturbances and when diversity is measured beyond species richness alone.

This study evaluated the predictions of the …

I’M A Forest, Not A Saltmarsh, Captain: Carbon And Sap Flow Dynamics In Coastal Forested Wetlands Of The Southeastern United States, Chris Shipway

All Theses

Coastal forested wetlands are identified as some of the highest-priority ecosystems for climate change mitigation. Here, we present two studies conducted in these unique ecosystems.

The first assessed changes in aboveground vegetative C stocks along the estuarine-riverine gradients of the Winyah Bay in South Carolina and the Savannah River in Georgia, using a space-for-time substitution to increase understanding of the impacts to upper estuarine forested wetlands from relative sea level rise. Standing C stocks on the Savannah River averaged 183.6 Mg C ha^-1, while sites on the Winyah system averaged 162.3 Mg C ha^-1. The largest …

New York City’S Rising Sea Level And Coastal Erosion: Approaches To Resiliency, Ryder D. Isidro

Student Theses 2015-Present

No abstract provided.

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Quantifying The Ecological Effects Of Salix Fragilis On Riparian Habitat In Kittitas County, Washington, Landon Shaffer

All Master's Theses

Invasive species threaten plant community structure and function globally. Riparian areas, the zone near streams where water influences vegetation, are especially sensitive to invasive species colonization, suffering large-scale shifts in community composition. Salix fragilis (crack willow) is a nonnative riparian species abundant in the lower elevation tributaries of central Washington. Some speculate whether this willow should be listed as invasive in Washington, despite a lack of regional supporting evidence. I studied riparian communities dominated by either S. fragilis or native species in the Kittitas Valley and measured biodiversity, quantified differences in solar attenuation, and compared leaf decomposition rates to learn …

Germination Trends Of American Chaffseed, Schwalbea Americana L., And Factors Affecting First-Year Seedling Development, Trenton Miller

All Theses

Following centuries of exploitation and fire suppression, longleaf pine systems are now the focus of many conservation efforts. Efforts to restore populations of Schwalbea americana L. in longleaf pine savannas have been met with frustratingly low recruitment. While past studies have briefly quantified germination rates for Schwalbea, there have not been any studies yet that truly investigate this plant’s germination requirements. Additionally, there has been little research into characterizing the parasitic relationship between Schwalbea and its various host species. We conducted a germination study in a growth chamber that investigated Schwalbea’s germination rate and time to germinates as …

Bryophyta Sensu Stricto Presence And Function In The Epiphytic Ecosystems Of The Tropical Montane Cloud Forests Of El Valle De Anton, Teaghan Duff

Independent Study Project (ISP) Collection

Bryophyta sensu stricto, colloquially known as moss, is often found growing epiphytically in cloud forest ecosystems. Under these conditions, moss may fulfill a secondary foundational species (FS) role, supporting increased habitat for other organisms while remaining dependent on the primary FS host tree. Exploring the dual relationship of moss as both a dependent and supportive organism allows for better understanding of its connective role within ecosystems. Research in the cloud forests of El Valle de Anton focused on relative abundance, environmental surroundings, morphology, and microclimate of mosses to offer baseline data on these connections. Mosses along four different trails within …

Variation Of Carbon Stock Of Boca Del Drago Mangrove Forests Based On Salinity And Seaward Proximity, Fiona Wyrtzen

Independent Study Project (ISP) Collection

Mangrove forests, at the intersection of land and sea, are considered one of the most important marine environments for their variety of ecosystem services and their ability to sequester large amounts of carbon in their biomass and adjacent soils. With a changing climate, many of the abiotic and biotic factors influencing mangroves will begin to shift, potentially impacting resilience, growth capacity, and distribution of mangroves worldwide. This study aimed to examine the influence of changing salinity on the carbon stock capacity for Rhizophora mangle and Laguncularia racemosa forests, and the distribution of biomass in each species relative to salinity in …

Bryophyte (Sl) Growth And Environmental Factors Along An Altitudinal Gradient On Cerro Gaital, El Valle, Coclé, Panamá, Julian Grace-Martin

Independent Study Project (ISP) Collection

Research on bryophytes (SL) in the tropics has been lacking compared with the high number of species found there and the potential benefit of bryophytes (SL) as indicators of pollutants and other forms of human disturbance. This study investigated whether or not bryophyte (SL) growth patterns showed relation when compared with environmental factors on the mountain Cerro Gaital in El Valley, Panamá. Whether or not bryophytes (SL) are present, extent of the area covered by their growth, and height of their growth are all aspects of bryophyte (SL) growth that were used. In this study, these three aspects are compared …

Evidence Of Competitive Release Following Overstory Mortality In A Semi-Arid Piñon-Juniper Woodland, Corrie D. Gonzalez

Biology ETDs

Extreme temperatures and severe drought events have led to widespread tree mortality worldwide. In semi-arid regions of the Southwest United States, these events pose a significant threat to piñon-juniper (PJ) woodlands. We studied the effects of piñon and juniper mortality on the growth and physiology of existing saplings in PJ woodlands by analyzing water status, photosynthetic activity, and tissue chemistry to gain insights into these impacts. Juniper saplings exhibited improved water status and water use efficiency in response to overstory mortality, whereas piñon saplings did not. Additionally, both piñon and juniper saplings exhibited increased photosynthetic rates, increased photosynthetic capacity, and …

Do Species Matter? Examining The Niche Of White Ash (Fraxinus Americana L.) And Estimating Potential Subcanopy Effects Of Its Loss In North-Temperate Forests, Elizabeth Anne Studer

Dartmouth College Ph.D Dissertations

To understand the downstream consequences of the extinction of a species, we must understand its role in an ecosystem. With the impending extirpation of ash (Fraxinus spp.) due to the invasive emerald ash borer (Agrilus planipennis), understanding the role of ash trees is critical to predicting whether its loss will precipitate further species declines and/or ecosystem functions. We evaluated whether subcanopy microbial, invertebrate, and floral communities under four tree species (white ash, American beech, yellow birch, sugar maple) and on two soil hydropedological types (Bh podzol and Typical podzol) varied in species richness, composition, and functional traits in a factorial …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

Sequencing Antisense Transcriptome Of Populus Through Antisense/Sense Transcript Pair Enrichment, Emma V. Burke

Dissertations, Master's Theses and Master's Reports

Past transcriptome research on plants focused primarily on protein coding genes, and only recently researchers began looking into the non-protein coding regions that may play significant roles in gene regulation. Antisense RNA transcripts that are found naturally in the cell share complementary sequence with sense transcripts and have been shown to regulate expression of their sense counterparts. Since antisense RNA has been largely under-studied and difficult to sequence because of their low relative abundance, new methods are needed to target antisense RNA for efficient genome-wide profiling. To address this gap in methods to efficiently and cost effectively enrich antisense RNA …

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …

Callery Pear Allelopathy Study, Michaela J. Woods, Jonathan T. Bauer, Dena Schaeffer, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

No abstract provided.

Assessing Turgor Loss Point In Bottomland Hardwood Trees Using Leaf Spectroscopy, Alexandra M. Eisley

LSU Master's Theses

Climate change is expected to radically alter our planet’s forests, with higher frequencies of drought- and flood-induced mortality events posing a challenge for forest managers and biologists. Research into the factors underlying plant tolerance to environmental stressors is therefore gaining popularity for incorporation into projective and earth system modeling using remote sensing measures. Leaf turgor loss point (TLP) is a key trait associated with drought tolerance among plants and is defined as the water potential at which leaf turgor pressure reaches zero, causing wilting. Here, I investigated patterns of TLP across the landscape and its role as an indicator of …

Wetlands In Our Backyard: A Review Of Wetland Types In Virginia State Parks, Kirsten Bauer, Benjamin K. Campbell

Virginia Journal of Science

Wetlands constitute a significant component of Virginia’s natural resources and heritage. Though historically they have been discounted—and often denigrated—the exceptional value of wetlands is currently growing in recognition and appreciation. In addition to the value provided by extracted resources and ecological regulation, wetlands also offer people the opportunity to enrich themselves through cultural, educational, and recreational pursuits. The state parks of Virginia provide access to a variety of ecosystems, including a wide array of wetland types. In this review, we document the diversity of wetlands in Virginia State Parks through a typology that groups wetland systems into the three principal …

The Effects Of Drought And Shade On Bottomland Hardwood Regeneration, Charles Joseph Pell

LSU Doctoral Dissertations

Floodplain forests support a high diversity of tree species adapted to regenerate under fluctuating water and light availability. Regeneration regulates species composition, and shade and flood tolerance influence the likelihood of regeneration. Regeneration failure of shade-intolerant and flood-tolerant tree species commonly occurs in southcentral and southeastern floodplain forests of the United States, also known as bottomland hardwoods (BLHs). In many BLHs reduced flooding has resulted in a dryer floodplain. These changes in flooding are linked to recent shifts in species composition. The mechanisms controlling regeneration in BLHs and these composition shifts are poorly understood. In a controlled germination experiment, I …

Restoration Through Reassembly: Evaluating The Role Of Native Plants In Combatting Chinese Tallow, Olaniyi Ajala

Electronic Theses and Dissertations

Non-native, invasive species disrupt ecological processes and functions, posing a serious threat to natural ecosystems. By examining the growth metrics of the non-native, invasive tree, Chinese tallow (Triadica sebifera [L.] Roxb.), hereafter tallow, across different flooding and light regimes, I investigated how restructuring native communities with valuable native species will prevent the reestablishment of tallow. I studied the changes in morphological and physiological traits of tallow when growing with water tupelo (Nyssa aquatica L.), sugarberry (Celtis occidentalis L.), and green ash (Fraxinus pennsylvanica Marshall). I found that in the non-flooded and high irradiance treatments, tallow's growth …

Leaf Phenology Of Callery Pear: Frost Damage, Margaret E. Maloney, Abby Hay, Eric B. Borth, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

This dataset is one of three affiliated with the paper "Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana Roseaceae) and potential native competitors."

The other two datasets are:

• Leaf Phenology of Callery Pear: Spring
• Leaf Phenology of Callery Pear: Fall

Leaf Phenology Of Callery Pear: Spring, Margaret E. Maloney, Abby Hay, Eric B. Borth, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

This dataset is one of three affiliated with the paper "Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana Roseaceae) and potential native competitors."

The other two datasets are:

• Leaf Phenology of Callery Pear: Fall
• Leaf Phenology of Callery Pear: Frost Damage

Leaf Phenology Of Callery Pear: Fall, Margaret E. Maloney, Abby Hay, Eric B. Borth, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

This dataset is one of three affiliated with the paper "Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana Roseaceae) and potential native competitors."

The other two datasets are:

• Leaf Phenology of Callery Pear: Spring
• Leaf Phenology of Callery Pear: Frost Damage

Geospatial Data Trees 1981, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

Data Files for Old-Growth Deciduous Forest Dynamics Archive: Hueston Woods

Location and demographic data collected for each individual tree in 1981 in Hueston Woods State Nature Preserve. These maps were digitized from the historical field maps to a GIS shapefile for each sampling year. Geographic Coordinate System: GCS_North_American_1983. Projected Coordinate System: NAD_1983_StatePlane_Ohio_South_FIPS_3402 (meters).

Callery Pear Removal Experiment: Trees-Intact (Medlar Conservation Area), Margaret E. Maloney, Eric B. Borth, Grace Dietsch, Mary C. Lloyd, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

The invasive tree Callery pear (Pyrus calleryana) is problematic in open habitats in the American Midwest. We investigated the efficacy of various control techniques on P. calleryana invasion in grasslands. Treatments were applied to P. calleryana stems that were single-stemmed trees (around 7 years; n = 40 stems), and response of those stems was measured.

Callery Pear Removal Experiment: Trees-Sprouting (Stillwater Conservation Area), Margaret E. Maloney, Eric B. Borth, Grace Dietsch, Mary C. Lloyd, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

The invasive tree Callery pear (Pyrus calleryana) is problematic in open habitats in the American Midwest. We investigated the efficacy of various control techniques on P. calleryana invasion in grasslands. Treatments were applied to P. calleryana stems that had experienced mowing annually for several years and were sprouting (n = 100 stems) and response of those stems was measured.

Geospatial Data Permanent Plot, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

Data Files for Old-Growth Deciduous Forest Dynamics Archive: Hueston Woods

Permanent plot GIS shapefile that measures 100m x 105m and consists of 420 contiguous 5m x 5m subplots. There are 21 transects that run from south to north and 20 subplots per transect that run east to west. This downloadable data is a zipped file containing 8 shapefile building blocks. Geographic Coordinate System: GCS_North_American_1983. Projected Coordinate System: NAD_1983_StatePlane_Ohio_South_FIPS_3402 (meters).

Field Maps 2022, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

Data Files for Old-Growth Deciduous Forest Dynamics Archive: Hueston Woods

Historical field map scans (2022) for the permanent 100m x 105m research plot in Hueston Woods State Nature Preserve.

Geospatial Data Trees 1994, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

Data Files for Old-Growth Deciduous Forest Dynamics Archive: Hueston Woods

Location and demographic data collected for each individual tree in 1994 in Hueston Woods State Nature Preserve. These maps were digitized from the historical field maps to a GIS shapefile for each sampling year. Geographic Coordinate System: GCS_North_American_1983. Projected Coordinate System: NAD_1983_StatePlane_Ohio_South_FIPS_3402 (meters).