Life Sciences Commons^™

Ecological Dynamics In Compost-Amended Soils And The Resulting Effects On Escherichia Coli Survival, Anya Cutler

Graduate College Dissertations and Theses

Escherichia coli (E. coli) are common and typically innocuous copiotrophic bacteria found in the mammalian gut microbiome. However, over the past 30 years, pathogenic E. coli have been responsible for several outbreaks of foodborne illness linked to contaminated produce. The introduction of Escherichia coli to an agricultural soil, via contaminated water, compost, or raw manure, exposes the bacterium to a medley of ecological forces not found in a mammalian gut environment. This study assesses a variety of abiotic and biotic soil factors that influence the ability of an "invasive" copiotrophic coliform bacterium to survive in compost-amended agricultural soil. The study …

Edge-Of-Field Water And Phosphorus Losses In Surface And Subsurface Agricultural Runoff, Laura B. Klaiber

Graduate College Dissertations and Theses

Quantifying effectiveness of soil management practices on surface and subsurface water quality at the field scale is becoming increasingly important in the Lake Champlain Basin and other agricultural watersheds. During 2012 and 2013, field plots (22.9 x 45.7 m) were established at the Lake Alice Wildlife Area in Chazy, NY to begin a long-term water quality monitoring study. Plots were established in a cool season grass field (1 ha) leased and managed by the William H. Miner Agricultural Research Institute in Chazy, NY. The soil type transitions from an excessively drained outwash soil on the upslope to a very poorly …

A Multiscale Analysis Of The Factors Controlling Nutrient Dynamics And Cyanobacteria Blooms In Lake Champlain, Peter D. F. Isles

Graduate College Dissertations and Theses

Cyanobacteria blooms have increased in Lake Champlain due to excessive nutrient loading, resulting in negative impacts on the local economy and environmental health. While climate warming is expected to promote increasingly severe cyanobacteria blooms globally, predicting the impacts of complex climate changes on individual lakes is complicated by the many physical, chemical, and biological processes which mediate nutrient dynamics and cyanobacteria growth across time and space. Furthermore, processes influencing bloom development operate on a variety of temporal scales (hourly, daily, seasonal, decadal, episodic), making it difficult to identify important factors controlling bloom development using traditional methods or coarse temporal resolution …

Earthworms In Vermont Forest Soils: A Study Of Nutrient, Carbon, Nitrogen And Native Plant Responses, Ryan Melnichuk

Graduate College Dissertations and Theses

Anthropogenic activities surrounding horticulture, agriculture and recreation have increased dispersal of invasive earthworms. The introduction of earthworms initiates many physical and chemical alterations in forest soils previously unoccupied by earthworms. Three trials were performed to assess the effects of earthworms on soil-water dynamics, C and N and defensive/storage compound production by a native plant.

The first trial was a greenhouse experiment, performed to assess the impact of two ecologically contrasting invasive earthworm species on percolate and evaporative soil water loss. Mesocosms were constructed to simulate a typical forest Entisol commonly penetrated by the species of interest, Lumbricus terrestris and Amynthas …