Botany Commons^™

Bryophytes At Cave Entrances Across A Range Of Anthropogenic Disturbance, Morghan Mccool

2023 Midwest Ecology & Evolution Conference

Cave entrances are critical ecosystems in their role as ecotones between the interior cave environment and the surrounding external environment. Bryophytes serve as ecosystem engineers of cave entrance microhabitats. This study piloted a method to quantify anthropogenic disturbance unique to cave entrances and characterize the bryophyte assemblages at caves in urban and other natural areas. Bryophytes and environmental variables were sampled from cave entrances; bryophytes were identified, alpha and beta diversity values were computed. So far, 144 species of bryophytes, 36 of which were state records, have been identified across 6 sites. By improving knowledge of bryophyte communities, park managers …

Understory Epiphyte Hydrology: Analyzing Water Storage Capacity Of Epiphytes Along An Elevational Gradient In Western Ecuadorian Cloud Forest, Angelina Dodge

Independent Study Project (ISP) Collection

Epiphytes are defined as plants that grow on a host, often another plant, and acquire their nutrients and water from the atmosphere. As such is true, epiphyte composition is largely dependent upon atmospheric and thus climactic conditions. Due to high levels of atmospheric water availability that results from the frequent presence of mist, clouds, and high humidity, epiphytic plants grow and thus store water within the above ground region of the Andean cloud forest at levels higher than in any other ecosystem found in Ecuador. This study was done in hopes of revealing any trends of epiphytic water storage capacity …

Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy

Master's Theses

Lichens are among the most prominent and successful life forms of metal-rich habitats, including ultramafic rocks and soils; however, research on lichens of ultramafic habitats is limited, especially on the North American continent. A review of the published literature on lichens of ultramafic substrates in North America yielded a total of 437 lichen species reported from ultramafic rocks and soils. Lichen assemblages of ultramafic substrates vary in composition and are dominated by acidophytic (low pH preferring) taxa with a minor, but consistent, basiphytic (high pH preferring) component. Species lists from ultramafic habitats in different geographic regions varied widely, suggesting that …

Prevalence Of Hesperevax Sparsiflora Var. Brevifolia (Short-Leaved Evax) At Ocean Ranch, Humboldt County, California: Exploring The Effects Of Disturbance, Shelby Diquirco, Matthew Estrada, Alana T. Fraley, Alexander D. Smith

Environmental Science & Management Senior Capstones

The prevalence of special-status plants within a landscape can be an indicator of the ecological health of that site, and therefore inform restoration efforts and post-restoration monitoring. Hesperevax sparsiflora var. brevifolia (short-leaved evax) is a special status species found within the Ocean Ranch unit of Humboldt, California. A primary threat to native plant communities are invasive plant species. Coastal dune ecosystems are largely dominated by invasive species, including Ammophila arenaria (European beachgrass). To work towards the eradication of A. arenaria, the California Department of Fish and Wildlife utilized treatment combinations of herbicide and prescribed fire at Ocean Ranch in …

Restoring An Iconic Joshua Tree Forest: Natural Recovery, Restoration Success, And Soil Microhabitats On A Desert Burn Area, Riley Scaff

Pitzer Senior Theses

Wildfires are a novel disturbance type in the Mojave Desert, but have been increasing in size and frequency since the 1970s due to the proliferation of invasive grasses. Burned areas are more susceptible to invasion, which can lead to the establishment of a grass-fire cycle. For this reason, restoration is often necessary to facilitate natural plant community recovery, but the extreme desert climate makes returning native vegetation to burn areas challenging. Planting in nutrient-rich soil microhabitats could be a helpful tool to improve revegetation success, but has yet to be tested. This study surveyed natural postfire recruitment across two seasons …

Demography And Habitat Associations Of The Basalt Cactus: Pediocactus Nigrispinus, Zarha Dillon-Zuppelli

All Master's Theses

Cacti are iconic, conspicuous, and important contributors to arid ecosystems. They stabilize soil and provide essential food and habitat to wildlife. Pediocactus nigrispinus is a species of cactus endemic to the Pacific Northwest and has been listed as a sensitive species due to its vulnerability to habitat loss. Pediocactus nigrispinus is being threatened by habitat fragmentation, poaching, and a changing climate. Best conservation methods for this species are poorly understood, due in part to a limited understanding of its demography and associations that may help define its occurrence.

A demographic study in Washington State was implemented in 2016 to give …

Pasture Condition Guides For The Southern Rangelands, Including The Gascoyne, Murchison And Goldfields-Nullarbor, Peter-Jon A. Waddell, Philip We Thomas, Wayne J. Fletcher, Kath Ryan, Joshua E. Foster, John K. Stretch, Jim S. Addison

Bulletins 4000 -

These guides address a recognised gap in readily applicable and easily accessible information on southern rangelands pasture condition and management.

These guides provide descriptions and images for southern rangelands pastures with similar management requirements for the grazing of native pastures by livestock. Therefore, the focus is on palatability of vegetation to livestock, and the effects of livestock management and external factors on the condition of the vegetation and soils.

The first section provides an overview and map, introduces concepts and terms important to understanding arid shrubland management in general, these guides in particular, and includes an economic analysis of the …

Csi Botany: Dna Barcode “Fingerprints” Identify Cryptic Urban Flora, Luis R. Vega

Theses and Dissertations

As short genomic markers, DNA barcodes can play a role in conservation by identifying cryptic species and hybrids when morphological approaches fall short. Here we present our application of barcodes to the identities of two wetland taxa as part of an ongoing floristic inventory of Van Cortlandt Park (VCP), Bronx, NY. Previous barcode data by Marriott et al. (2018) identified the VCP lake water lily as the exotic Nymphaea alba, rather than the native N. odorata as historically described. In addition, cattails in the park were historically identified as the native Typha latifolia and the exotic T. angustifolia …

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 …

Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang

Faculty Journal Articles

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, …

The Influence Of Cover Crops On Grassland Restoration, Josh C. Poland

Masters Theses

Grassland ecosystems comprise almost a fourth of all Earth’s land mass; however, due to ever-increasing rates of agricultural land conversion, these habitats are facing a large-scale biodiversity crisis. The degradation of grasslands extends beyond physical impacts, such as soil erosion, to include the loss of soil microbial communities as a serious risk to the health and productivity of these habitats. Cover cropping, commonly used in agriculture to revive agricultural soils, has rarely been applied to grassland restorations, and could combat or reverse the harmful effects of modern agriculture techniques. For the first chapter of my thesis, I used a greenhouse …

A Cladoxylopsid With Complex Vascular Architecture From The Early Devonian Battery Point Formation (Québec, Canada), Jessica Chu

Cal Poly Humboldt theses and projects

Cladoxylopsids are seed-free plants that formed the world’s earliest forests and gave rise to horsetails (sphenopsids), but their evolutionary origins are poorly understood. Here, I describe a new Early Devonian cladoxylopsid from the Emsian (400-395 Ma) Battery Point Formation (Québec, Canada). The structural features of this plant indicate taxonomic affinity to cladoxylalean cladoxylopsids and its phylogenetic position supports placement in genus Cladoxylon (the proposed name, Cladoxylon kespekianum sp. nov., to be formalized by peer-reviewed publication). Specimens of this plant are permineralized in calcium carbonate and were studied using the acetate peel technique with light and electron microscopy. Cladoxylon kespekianum is …

Using Micro Satellites To Assess The Impact Of Algae Growth On Global Warming, Hursh, Vanessa

Student Works

Data gathered from microsatellites can inform policymakers and environmental agencies about the impact of algae on global warming. It can guide the development of strategies to mitigate or harness the potential benefits of algae growth.

Discerning Friend From Foe: Systematic Revision Of Cuscuta L. Section Indecorae Using A Combined Ecological, Morphometric, And Phylogenetic Approach., Corey Burt

Theses and Dissertations (Comprehensive)

The genus Cuscuta (Dodder; Convolvulaceae) are obligate parasitic plants. In one clade known as section Indecorae, there are species which are considered pests that pose significant threats to agricultural crop production, while other species are rare or known only from historical records. Section Indecorae contains three species: C. coryli, C. warneri, and C. indecora (the latter with three infraspecific taxa: var. indecora, var. longisepala, and var. attenuata). The systematics of section Indecorae are not currently resolved. Cuscuta indecora has a long and complicated taxonomic history with many infraspecific varieties described, and …

Investigating The Effects Of Disturbance And Competition On Establishment, Growth, And Reproduction Of The Endangered Ripariosida Hermaphrodita, Daniel Engelking

Theses and Dissertations (Comprehensive)

Ripariosida hermaphrodita (Virginia Mallow) is a perennial riparian plant with broad, maple-like leaves. It grows up to three meters high and is often found in large clonal patches, but sexually reproduces readily. While this plant may seem like a redoubtable competitor when growing in large colonies, it is declining across its range in North America. The only known occurrences in Canada are in southern Ontario. Prior to this study, no new populations had been recorded even though one of the known populations produces copious amounts of viable seed with potential to disperse. There are many hypotheses for its rarity, but …

Establishment Of The Invasive Cactus Moth, Cactoblastis Cactorum (Berg) (Lepidoptera: Pyralidae) In Pakistan: A Potential Threat To Cultivated, Ornamental And Wild Opuntia Spp. (Cactaceae), Muhammad Ather Rafi, Harry Pavulaan, Muhammad Islam, Muhammad Ashfaq, Haseeb Kamran, Walija Fayaz, Gul Naz Parveen, Riffat Sultana, Ahmad Zia, Waqar Ahmed, Qudrat Ullah, Muhammad Qasim, Falak Naz, Nazeer Ahmed, Muhammad Tariq Khan, Muhammad Saeed, Jalal Hayat Khan

The Taxonomic Report of the International Lepidoptera Survey

Subsequent to the significant accomplishment of biological control of Opuntia weeds in Australia, the larvae of the cactus moth, Cactoblastis cactorum (native to parts of South America), were released in many countries for the biological control of native Opuntia species (Simmonds and Bennett, 1966). Inauspiciously, larvae were also released in the Caribbean, where the moth spread naturally and by the human support all over the region (García-Turudi et al., 1971). Its enhanced dissemination rate and the biological potential for invasiveness, suggests that the cactus moth is likely to become an invasive pest of Opuntia in the Southeast United States, Mexico, …

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …

Taxonomic Revision And Morphometric Analysis Of Selected Anthurium (Araceae) Species From Bolivia And Peru, Daniel M. Tarazona Ocana

Theses

The genus Anthurium (Araceae) consists of around 1,200 species distributed in the Neotropics, particularly in Central and South America. The montane forests in the eastern flank of the Andes, ranging from northern Ecuador to central Bolivia; hereafter, the East Andes Gradient region, are particularly rich in terms of species diversity, and include an understudied group of Anthurium species endemic to the region. Within this group of species, some taxa are difficult to distinguish from each other mainly due to the lack of identification keys, incomplete species descriptions and unknown synonyms. In this study, a combination of traditional taxonomic techniques and …

The Ecology And Evolution Of Species Rarity In Oaks (Quercus Spp.), Yingtong Wu

Dissertations

Rare species are susceptible to extinction due to ecological and genetic factors. Understanding the distribution, ecology, and evolution of rare species can provide useful information for effective conservation. To investigate species rarity, this dissertation focuses on a species-rich and ecologically diverse genus, Quercus (oaks). In Chapter 1, I aimed to understand how interactions between hosts and soil microbes contribute to habitat restriction in oak species. I performed a soil inoculum experiment on two pairs of sister oak species that show habitat divergence. I found that host-specific soil microbes contribute to habitat divergence and exclusion among sister species of oaks, but …

Arthropod Assemblages At The Intersection Of Epiphyte And Soil Habitats: An Assessment Of Understory Level Nonvascular Epiphyte Communities And Their Connectivity Within A Tropical Montane Rainforest, David “Max” Jones

Independent Study Project (ISP) Collection

Canopy arthropods communities represent a disproportionate amount of global species richness (Stuntz 2001). Understanding arthropod composition and connectivity of lower epiphyte communities is important in understanding how canopy arthropods communities are formed and will respond to change (Floren and Linsenmair 1998). As such this study examined arthropod assemblages living within nonvascular epiphyte communities (epiphyte mats) living directly upon lower trunk regions of 24 trees in a tropical montane rain forest within the Santa Lucia Nature Reserve in Pichincha, Ecuador. Trees were assessed for size, epiphyte diversity, and epiphyte coverage before arthropod sampling within the epiphyte mats. Soil assessments were taken …

Afforestation And Biodiversity: Bryophyte Richness Changes Between Icelandic Forest Types, Kian Mcdonough

Independent Study Project (ISP) Collection

Forest-dwelling bryophytes (mosses, liverworts, hornworts) greatly contribute to biodiversity and ecosystem function but are largely under-studied in comparison to vascular plants. With Iceland’s large-scale afforestation efforts there is a need to understand how different afforestation species are affecting biodiversity, including bryophyte diversity. This study looked at differences in ground-floor bryophyte richness across Sitka spruce, lodgepole pine, and downy birch forests and found that bryophyte richness was highest in the Sitka spruce forests and lowest in downy birch forests. While this suggests a negative correlation between bryophyte richness and light availability, since the conifer species have the densest copy cover, other …

Investigating Primary Succession Following The Retreat Of The Breiðamerkurjökull Glacier, Iceland, Ella Roelofs

Independent Study Project (ISP) Collection

The accelerating rates of glacier retreat around the world as a result of climate change make the study of primary succession in expanding forefields increasingly important. While this is a well studied topic in many parts of the world, little data exists specific to Iceland. This study investigated vegetation development along a chronosequence of eight time periods in the Breiðamerkurjökull outwash plain. Data was collected on percent vegetation cover, dominant species, the number of unique plant groups, and percent cover of five substrate types at 10 plots (0.55 x 0.55 m quadrats) per time period. Important findings include the fact …

Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin

LSU New Orleans Theses and Dissertations

Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …

Hiding In Plain Sight: Accounting For Rate Heterogeneity In Trait Evolution Models, James Boyko

Graduate Theses and Dissertations

Within the last four decades, phylogenetic comparative methods have become the defacto method of analysis for comparative biologists. The availability of high-quality comparative datasets has been matched by an explosion of possible phylogenetic models. In large part, the efforts to increase the realism of phylogenetic comparative methods has been successful as evidenced by their widespread use. To this extensive literature, my contributions are modest. I have focused my dissertation work on two main themes. First, most phenotypic evolution is not independent of other phenotypes. Changes in a particular character may influence changes in another and modeling these characters in isolation …

The Influences Of Disperser Behavior, Host Availability, And Environmental Conditions On The Distribution Of Oak Mistletoe [Phoradendron Leucarpum (Raf.) Reveal & M. C. Johnst.] In Eastern Virginia And North Carolina, Nicholas Pearce Flanders

Biological Sciences Theses & Dissertations

Mistletoes are shrubs that typically parasitize the branches of host trees and rely on avian frugivores for seed dispersal. Because mistletoes are restricted to a narrow range of suitable recruitment sites and avian frugivores are more visible than other guilds of seed dispersers, mistletoe-frugivore systems afford opportunities for assessing the roles of dispersal limitation and local environment in determining plant distribution. These mechanisms have been proposed as determinants of the observed association of oak mistletoe [Phoradendron leucarpum (Raf.) Reveal & M. C. Johnst.] with forested wetlands in eastern Virginia and North Carolina, USA. I tested the alternative hypothesis that …

Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart

Biology Theses

Organisms produce chemical weapons for defense, but target organisms can develop resistance. In their introduced range, non-native species may bring “novel weapons” against which native organisms have not co-evolved resistance. The invasive European fire ant (Myrmica rubra) may have brought antimicrobial secretions to the Northeastern United States that are novel weapons against native fungal and bacterial soil organisms. I hypothesized that M. rubra would better inhibit seed pathogens resulting in greater emergence of native myrmecochorous Viola sororia seeds and, as a side effect, more strongly inhibit arbuscular mycorrhizal fungi than a native seed dispersing ant (Aphaenogaster picea …

Winter Cover Crop Impacts On Weed Dynamics In Eastern And Central Nebraska, Elizabeth Ann Oys

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Reducing tillage in cropping systems causes weed management to be dependent on chemical and cultural methods for weed control. Over time, herbicide-resistant weeds have developed due to the continuous selection pressures from herbicides, particularly in the Midwest Corn Belt. Integrated weed management strategies, such as cover crops, can be used to mitigate some of these issues. Cover crops are primarily known for their soil health benefits, but there is evidence that cover crops can suppress weeds. However, less research has been done at the field-scale level to address cover crop impacts on the weed seedbank and aboveground weeds during the …

Temporal Dynamics And Seed Dispersal In Plant-Frugivore Communities Of The Dominican Republic, Spencer Christian Schubert

Biological Sciences Theses & Dissertations

Plant-animal mutualisms are a foundational component of biodiversity in terrestrial ecosystems. Most tropical forest plants have adapted to produce fleshy fruits to attract frugivorous animals to disperse seeds. Interaction patterns among plant taxa and their seed dispersers are driven by a complex suite of factors involving their evolutionary history and environmental context, and the structure of these mutualistic networks are theoretically tied to their ecological function. I carried out a series of field studies to investigate the temporal dynamics of mutualistic interactions of plant and avian frugivore communities in the central Dominican Republic and how their characteristics affect seed dispersal …

Cryptic Hybridization In The Temperate Bamboos: Is Pleioblastus Simonii A Species Of Hybrid Origin?, Morgan Brown

Theses

Japanese river bamboo (Pleioblastus simonii, ‘medake,’‘kawadake’) is an ecologically important species of temperate bamboo native to Japan. This species is widely known and historically important in Japanese rural farm life. Based on morphological data, Japanese river bamboo is classified in Pleioblastus section Medakea (Poaceae: Bambusoideae) along with five other Japanese species, which are collectively considered to represent a phylogenetically distinct lineage. However, recent studies suggest that Japanese river bamboo may have arisen as a result of previously undetected hybridization (i.e., cryptic hybridization), while also calling into question the diversity of section Medakea. The role of hybridization in natural plant populations …

Western Prairie Fringed Orchid Management, Ecology, And Decline At Mormon Island, Andrew J. Caven

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The western prairie fringed orchid (Platanthera praeclara Sheviak & M. L. Bowles; WPFO) was first detected in a vegetative state on Mormon Island in 1978 and identification was confirmed following a mass flowering event in 1982. From a high count of ~60 plants the WPFO slowly declined and has not been observed since 2000 despite flowering season surveys conducted in 15 of the last 20 years. We explore the natural history of the WPFO in the contexts of Mormon Island to establish potential causes for its apparent disappearance and evaluate the possibility it persists in some capacity. Our investigation …