Life Sciences Commons^™

The Discovery Of A Novel Bacteria From A Large Co-Assembly Of Metagenomes, Matthew Finkelberg

Masters Theses

In the summer of 2022, a co-assembly of metagenome was created using the microbes found at Barres Woods in Harvard Forest. 14 samples were taken, and sample was split into the organic and mineral layer, which totals 28 Bulk MAGs. Within this Co-assembly, 4 different genomes were found which were designated with the phylum of FCPU426. Three of which were considered medium quality and one being assigned high quality. The novel phyla first appeared in NCBI and GTDB databases in June 2018. The name FCPU426 dates to 2010 and was named based on the 16s amplicon sequencing.

The novel phylum …

Geomorphology Of Tidal Wetlands: Impacts Of Extreme And Annual Flood Events To Salt Marsh And Mangrove Systems, Frances R. Griswold

Doctoral Dissertations

Tidal wetlands are vital for buffering coastal settings from the threats of accelerated sea level rise and storms. Understanding the factors that are most influential for the maintenance and recovery of tidal wetlands after extreme events compounded by future accelerated sea level rise is of the utmost importance, yet this knowledge is not well established. Two tidal wetland schemas investigated in this dissertation are mangrove systems in Vieques, Puerto Rico (including robust lagoonal-mangrove forest systems and fringing mangrove forests), and salt marshes in New England. While the climatic forcings, vegetation type, and locations are vastly different for these two tidal …

Perceptions Of Historical Climate Change And Park Policy: The Impact On The Fremont Cottonwood In Zion National Park, Kathleen Kavarra Corr

Doctoral Dissertations

Despite its “natural” appearance and the Organic Act 1916 mandate for preservation of the natural environment in National Parks, the Virgin River as it flows through Zion National Park’s Zion Canyon was transformed through massive flood control re-engineering projects in the 1930s. The armoring of the river has had significant impacts on riparian vegetation, particularly on the stands of native Fremont Cottonwood trees that once filled the narrow valley. What was the motivation for this massive flood control project carried out in an arid region with less than 15 inches of rain per year? This dissertation explores the motivations which …

Garlic Mustard (Alliaria Petiolata) Management Effectiveness And Plant Community Response, Erin Coates-Connor

Masters Theses

The control and eradication of the invasive biennial herb garlic mustard (Alliaria petiolata) and the restoration of invaded forest habitats present important linked challenges to land managers in North America. Removing garlic mustard by hand and by glyphosate herbicide application have both been used as eradication strategies with mixed results. Each method has advantages and disadvantages, but they are rarely compared for effectiveness and community impact across multiple years of management. Some previous studies have shown improvements in species diversity and plant community composition following management, while others have found no differences. To better understand both garlic mustard …

Factors Influencing Impact Of Biological Control Agents Of The Emerald Ash Borer, Theresa Murphy

Masters Theses

Agrilus planipennis, the emerald ash borer (EAB), is a destructive invasive forest pest decimating North American ash trees. Population-wide management of EAB focuses on biological control, with the introduction of four parasitic wasps; one egg parasitoid, Oobius agrili and three larval parasitoids- Spathius galinae, Spathius agrili and Tetrastichus planipennisi. This thesis examines some of the factors influencing the establishment of these larval biocontrol agents. Chapter 1 examines the relationship between woodpeckers and the parasitoids S. agrili and T. planipennisi. Both woodpeckers and these parasitoids attack the larval stage of EAB, which means their impacts overlap and …

Understory Plant Community Structure In Forests Invaded By Garlic Mustard (Alliaria Petiolata), Jason Aylward

Masters Theses

ABSTRACT

UNDERSTORY PLANT COMMUNITY STRUCTURE IN FORESTS INVADED BY GARLIC MUSTARD (ALLIARIA PETIOLATA)

MAY 2016

JASON ALLEN AYLWARD, B.S., PAUL SMITH’S COLLEGE

M.S. UNIVERSITY OF MASSACHUSETTS AMHERST

Directed by: Professor Kristina Stinson

Plant invasions represent a significant threat to the structure and function of natural ecosystems. Garlic mustard (Alliaria petiolata) has been identified as a threat to native communities mostly through small-scale studies and focused experiments. In this in situ observational study I examined the effects of garlic mustard invasion on species composition across multiple sites by comparing plant diversity and composition in invaded and adjacent …

Density-Dependent Survival In The Larval Stage Of An Invasive Insect: Dispersal Vs. Predation, Adam A. Pepi

Masters Theses

1. The success of invasive species is often thought to be due to release from natural enemies. This hypothesis relies on the assumption that species are regulated by top-down forces in their native range and implies that species are likely to be regulated by bottom-up forces in the invasive range. Neither of these assumptions has been consistently supported with insects, a group which include many highly destructive invasive pest species.

2. Winter moth (Operophtera brumata) is an invasive defoliator in North America that appears to be regulated by mortality in the larval stage in its invasive range. To …

The Effect Of Thermoregulation And Roads On The Movements And Habitat Selection Of Moose In Massachusetts, David W. Wattles

Doctoral Dissertations

Massachusetts, U.S.A. is located along the southern boundary of the geographic range of moose (Alces alces) in North America. This is an atypical environment for moose, because of its extremely high levels of human development and high year-round temperatures, which are possibly at the limits of moose physiological tolerances. I investigated the role of these two factors on moose movements and habitat selection to determine how human development of the landscape and temperature influence moose occupation of this extreme environment. In addition, the response of moose to these factors provides insights into the influence of development and temperature …

Syllabus: Wildlife Habitat Management, Paige Warren

Sustainability Education Resources

This course provides an in-depth exploration of wildlife-habitat relationships, illustrated through basic field zoology and natural history, evolutionary biology, and ecological theory. We introduce you to quantitative tools used to explain ecological processes and their influence on wildlife and their environment. We will examine the dynamics and management of various habitats in New England, North America, and elsewhere through field visits and use of primary literature. We will place particular emphasis on managing wildlife habitat in an urbanizing world. By one estimate, roughly 9% of the land area of the United States is in a zone of wildland-urban interface, but …

Resin Volatiles Of Eastern Hemlock Induced By Its Non-Native Herbivores, Joshua D. Pezet

Masters Theses 1911 - February 2014

Eastern hemlock (Tsuga canadensis) is in decline because of infestation by the invasive hemlock woolly adelgid (Adelges tsugae; ‘HWA’) and, to a lesser extent, the elongate hemlock scale (Fiorinia externa; ‘EHS’). Many conifers respond to insect herbivory by inducing oleoresin-based defenses, however it is unknown whether eastern hemlock is capable of this inducible response. We conducted a plantation setting study of artificially infested saplings to determine if feeding by HWA or EHS induces changes in the tree’s volatile chemistry. The induced changes in volatiles we found were unlike the terpenoid-based defenses of related conifers. Only HWA feeding …

Growth And Establishment Of Newly Planted Street Trees, Alexander R. Sherman

Masters Theses 1911 - February 2014

Developing quantified establishment period estimates for newly planted trees will help set realistic goals for plant performance in the urban landscape. Nine years of tree planting records obtained from the city of Boston, MA and the town of Brookline, MA were used to derive samples of trunk caliper for hedge maple (Acer campestre), London planetree (Platanus x acerifolia), and red oak (Quercus rubra). Several site characteristics were measured to identify effects on newly planted tree growth.

Breakpoint estimates of the piecewise regression models fell at 4 years and 6 years for London planetree and …

Status, Movements, And Habitat Use Of Moose In Massachusetts, David W. Wattles

Masters Theses 1911 - February 2014

Moose (Alces alces) have been re-established in much of the historic range in the northeastern United States. Recently the southern edge of the species ranges has been extended southward into southern New England and northern New York from established populations in northern New England. The southern expansion raised questions as to the ability of this northern species to cope with higher temperatures, areas densely populated by humans, and different forest types further south. In light of these recent developments, we conducted a literature search on moose in the northeastern United States and distributed a questionnaire and conducted phone …

Evaluating The Influence Of Disturbance And Climate On Red Spruce (Picea Rubens Sarg.) Community Dynamics At Its Southern Range Margin, Relena R. Ribbons

Masters Theses 1911 - February 2014

Picea rubens(red spruce) populations experienced a synchronous rangewide decline in growth and vigor starting in the 1960’s, which was likely caused by climate change or environmental disturbances (e.g., acid deposition); However, it is yet unknown if populations continue to decline or have recovered. In the context of global warming, red spruce is a species of concern because it is at its southern continuous range margin in Massachusetts. This study uses tree-ring data coupled with population data from permanent plots to quantify the status of red spruce in Massachusetts. Tree cores were extracted from red spruce and used to examine …

Conservation Implications Of A Marbled Salamander, Ambystoma Opacum, Metapopulation Model, Ethan B. Plunkett

Masters Theses 1911 - February 2014

Amphibians are in decline globally and a significantly greater percentage of ambystomatid salamander species are in decline relative to other species; habitat loss contributes significantly to this decline. The goals of this thesis is to better understand extinction risk in a marbled salamander (ambystoma opacum) population and how forestry effects extinction risk. To achieve this goal we first estimated an important life history parameter (Chapter 1) then used a metapopulation model to estimate population viability and determine what aspects of their life history put them most at risk (Chapter 2) and finally predicted extinction risk in response to hypothetical forestry …