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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Anthropogenic Impacts To Essential Habitats In The Gulf Of Maine: A Case Study Of The American Lobster, Homarus Americanus, And Its Fishery, Andrew Goode Dec 2021

Anthropogenic Impacts To Essential Habitats In The Gulf Of Maine: A Case Study Of The American Lobster, Homarus Americanus, And Its Fishery, Andrew Goode

Electronic Theses and Dissertations

The Gulf of Maine has been fundamentally altered by anthropogenic forcings for decades and offers an ideal study system to monitor response to change. Through complex interactions between ocean warming, altered demographic bottlenecks, and reduced top-down controls, the American lobster (Homarus americanus Milne Edwards) capitalized on favorable conditions and proliferated within the Gulf of Maine. These changes catalyzed the expansion of the lobster fishery, elevated its status as North America’s most valuable marine resource, and shifted coastal communities towards a virtual lobster monoculture. The same processes that facilitated lobster to capitalize on favorable conditions may come with unintended consequences …


Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray Aug 2019

Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray

Electronic Theses and Dissertations

Over the past two decades, total nitrogen (TN) concentrations have increased in Casco Bay (CBEP 2015). The sources of the increased nitrogen are poorly understood but occur with simultaneous population growth and land use changes. The total riverine nitrogen load to Casco Bay was previously estimated by Liebman and Milstead (2012) using the United States Geologic Survey’s (USGS) SPAtially Referenced Regression On Watershed attributes (SPARROW) model. The SPARROW model uses watershed characteristics, regional monitoring data and nitrogen source data to estimate nitrogen loading but was not validated using measurements of nitrogen in the Casco Bay watershed. This study attempts to …


How Acidic Sediments And Seawater Affect Interactive Effects Of Predation On Survival, Growth, And Recruitment Of Wild And Cultured Soft-Shell Clams, Mya Arenaria L., Along A Tidal Gradient At Two Intertidal Sites In Eastern Maine, Brian F. Beal, William Otto Mar 2019

How Acidic Sediments And Seawater Affect Interactive Effects Of Predation On Survival, Growth, And Recruitment Of Wild And Cultured Soft-Shell Clams, Mya Arenaria L., Along A Tidal Gradient At Two Intertidal Sites In Eastern Maine, Brian F. Beal, William Otto

Miscellaneous Publications

No abstract provided.


Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams May 2018

Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams

Electronic Theses and Dissertations

Oyster aquaculture is an expanding industry that relies on identifying and utilizing natural estuarine conditions for the economically viable production of a filter-feeding crop. The eastern oyster, Crassostrea virginica, is the principal species currently cultured in Maine. In addition to preferentially consumed phytoplankton, various detrital complexes (non-algal and/or non-living organic matter) may provide some nutrition to C. virginica between times of phytoplankton abundance. Here I investigated the importance of detrital proteins in supporting the growth of oysters cultured in the upper Damariscotta Estuary. Oyster aquaculture in this area is highly successful and previous reports indicate that labile detrital protein …


Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon Dec 2017

Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon

Electronic Theses and Dissertations

Understanding lake vulnerability with respect to eutrophication and loss of water quality is important for sustainability of aquatic ecosystems. This project aims at identifying and quantifying the effects of relevant physiochemical, climate, and watershed characteristics on lake vulnerability in order to develop management decision tools for the Maine Department of Environmental Protection (MEDEP). In a changing chemical and physical environment, using independent variables from each of these categories and then relating them to the summer lake epilimnetic phosphorus (P) concentrations allows for development of models to inform stakeholders of lake vulnerability to eutrophication problems.

We studied 24 lakes covering a …


Using Hydroacoustics To Investigate Biological Responses In Fish Abundance To Restoration Efforts In The Penobscot River, Maine, Constantin C. Scherelis Aug 2017

Using Hydroacoustics To Investigate Biological Responses In Fish Abundance To Restoration Efforts In The Penobscot River, Maine, Constantin C. Scherelis

Electronic Theses and Dissertations

Spatiotemporal advantages linked to hydroacoustic sampling techniques have caused a surge in the use of these techniques for fisheries monitoring studies applied over long periods of time in marine systems. Dynamic physical conditions such as tidal height, boat traffic, floating debris, and suspended particle concentrations result in unwanted noise signatures that vary in intensity and location within a hydroacoustic beam over time and can be mixed with the acoustic returns from intended targets (e.g., fish). Typical processing filters applied over long term datasets to minimize noise and maximize signals do not address spatiotemporal fluctuations of noise in dynamic systems. We …


Crowdsourcing Water Quality Data Using The Iphone Camera, Thomas Leeuw May 2014

Crowdsourcing Water Quality Data Using The Iphone Camera, Thomas Leeuw

Electronic Theses and Dissertations

The ubiquity and advanced computing power of smartphones make them a potential tool for environmental monitoring on a global scale. In an attempt to tap this resource, a water quality application (HydroColor) was developed. Hydro- Color uses the iPhone’s digital color camera as a primitive three-band radiometer. Using three images taken by the user, HydroColor calculates the remote sensing reflectance in the red, green, and blue color channels of the camera. The absolute or relative reflectance between channels can be used to obtain estimates of chlorophyll, turbidity, suspended particle material, and the backscattering coefficient. In the future, HydroColor will be …


Tb207: A Manual For Remote Sensing Of Maine Lake Clarity, Ian M. Mccullough, Cynthia S. Loftin, Steven A. Sader Jan 2013

Tb207: A Manual For Remote Sensing Of Maine Lake Clarity, Ian M. Mccullough, Cynthia S. Loftin, Steven A. Sader

Technical Bulletins

The purpose of this manual is to support use of satellite-based remote sensing for statewide lake water-quality monitoring in Maine. The authors describe step-by-step methods that combine Landsat and MODIS satellite data with field-collected Secchi disk data for statewide assessment of lake water clarity. Landsat can be simul­taneously used to assess more than Maine 1,000 lakes ≥ 8 ha, whereas MODIS can be used to assess a maximum of 364 lakes ≥ 100 ha (250-m image resolution) or 83 lakes ≥ 400 ha (500-m image resolution). Although the methods were specifically developed for Maine, other states or non-Maine agen­cies may …


Signs Of The Seasons Program Species In Focus: Monarchs And Milkweed, An Ecological Relationship Threatened By Climate Change, Beth Bisson, Esperanza Stancioff Jan 2013

Signs Of The Seasons Program Species In Focus: Monarchs And Milkweed, An Ecological Relationship Threatened By Climate Change, Beth Bisson, Esperanza Stancioff

Maine Sea Grant Publications

Over the past two decades, researchers have observed declines in populations of both monarch butterflies (over 70% in some areas) and milkweed. Climate-related factors contributing to these declines include increasing frequency of intense winter storms and near freezing temperatures in monarch overwintering areas in Mexico, and severe droughts in the southwestern and southeastern United States, which affect both species. If these trends continue, they could create a mismatch in time or space between monarch breeding cycles along their northward migration (April to August) and the growth and survival of milkweed plants eaten by monarch caterpillars.


Tb202: Composition And Biomass Of Forest Floor Vegetation In Experimentally Acidified Paired Watersheds At The Bear Brook Watershed In Maine, Peter Kenlan, G. B. Wiersma, A. S. White, I. J. Fernandez Sep 2009

Tb202: Composition And Biomass Of Forest Floor Vegetation In Experimentally Acidified Paired Watersheds At The Bear Brook Watershed In Maine, Peter Kenlan, G. B. Wiersma, A. S. White, I. J. Fernandez

Technical Bulletins

The percentage cover (abundance), frequency of occurrence, biomass, species richness, and species diversity of understory herbs was measured on a paired watershed ecosystem in eastern Maine, USA. This paired watershed site (Bear Brook Watershed in Maine, BBWM) has had the West Bear Brook Watershed treated bi-monthly with granular ammonium sulfate at a rate of 28.8 kg S ha-1 yr-1 and 25.2 kg N ha-1 yr-1 since 1989. East Bear Brook Watershed serves as the reference site. More than 100 plots were randomly located across the two watersheds. The data suggest that there is generally a lower frequency of occurrence of …


Ice Core Record Of Rising Lead Pollution In The North Pacific Atmosphere, E. Osterberg, Paul Andrew Mayewski, Karl J. Kreutz, D. Fisher, Michael Handley, Sharon Sneed, C. Zdanowicz, J. Zheng, M. Demuth, M. Waskiewicz, J. Bourgeois Jan 2008

Ice Core Record Of Rising Lead Pollution In The North Pacific Atmosphere, E. Osterberg, Paul Andrew Mayewski, Karl J. Kreutz, D. Fisher, Michael Handley, Sharon Sneed, C. Zdanowicz, J. Zheng, M. Demuth, M. Waskiewicz, J. Bourgeois

Earth Science Faculty Scholarship

A high-resolution, 8000 year-long ice core record from the Mt. Logan summit plateau (5300 m asl) reveals the initiation of trans-Pacific lead (Pb) pollution by ca. 1730, and a >10-fold increase in Pb concentration (1981–1998 mean = 68.9 ng/l) above natural background (5.6 ng/l) attributed to rising anthropogenic Pb emissions from Asia. The largest rise in North Pacific Pb pollution from 1970–1998 (end of record) is contemporaneous with a decrease in Eurasian and North American Pb pollution as documented in ice core records from Greenland, Devon Island, and the European Alps. The distinct Pb pollution history in the North Pacific …


Tb196: Temperature, Soil Moisture, And Streamflow At The Bear Brook Watershed In Maine (Bbwm), Ivan J. Fernandez, Joseph E. Karem, Stephen A. Norton, Lindsey E. Rustad Dec 2007

Tb196: Temperature, Soil Moisture, And Streamflow At The Bear Brook Watershed In Maine (Bbwm), Ivan J. Fernandez, Joseph E. Karem, Stephen A. Norton, Lindsey E. Rustad

Technical Bulletins

The Bear Brook Watershed in Maine is a whole-ecosystem chemical manipulation initiated in 1987 to study the effects of acid deposition on forests and surface waters. The focus of this research was to understand the biogeochemical response of watersheds with emphasis on chemistry and hydrology. In 2001 a program was initiated to provide more detailed measurements of temperature and moisture to examine critical linkages amongst chemical, biological, and physical processes that ultimately work together to define ecosystem function. The purpose of this publication is to provide data from the initial phase of soil temperature, air temperature, and soil moisture measurements …


Effects Of Nitrogen Deposition And Flow Permanence On Stream Organic Matter Dynamics, Michael Andrew Joseph Chadwick Aug 2003

Effects Of Nitrogen Deposition And Flow Permanence On Stream Organic Matter Dynamics, Michael Andrew Joseph Chadwick

Electronic Theses and Dissertations

The objective of this study was to investigate the effects of N enrichment and flow permanence on stream organic matter dynamics at the Bear Brook Watershed in Maine (BBWM). BBWM is a paired-catchment manipulation of atmospheric (NH4)2SO4 deposition, and the goal of the experiment is to understand how increased N affects forested catchments. The treatment has increased stream nitrate and foliar N concentrations in the treatment watershed. Because streams draining BBWM are intermittent, this investigation provided an opportunity to investigate the combined effects of stream flow permanence and human alteration of N cycling in a …


An Interhemispheric Comparison Of The Recession Of Mountain Glaciers In The Last 150 Years, Colby Smith Jan 2003

An Interhemispheric Comparison Of The Recession Of Mountain Glaciers In The Last 150 Years, Colby Smith

Electronic Theses and Dissertations

Historical records in the Northern Hemisphere show overall glacier retreat since about AD 1860-1890. A glacial retreat of similar timing and magnitude in the Southern Hemisphere is less well established. Comparison of the timing and magnitude of glacial recession in the two polar hemispheres over the past century can elucidate mechanisms driving global climatic change. In order to determine the recession patterns of Murchison, Hooker, and Tasman Glaciers in the Southern Alps of New Zealand, geomorphic maps were constructed and recent glacial deposits were dated using lichenometry. Since the mid-to-late nineteenth century, each glacier terminus has retreated about 1.5 km. …


Can A Little Ice Age Climate Signal Be Detected In The Southern Alps Of New Zealand?, Jessica L. Black Aug 2001

Can A Little Ice Age Climate Signal Be Detected In The Southern Alps Of New Zealand?, Jessica L. Black

Electronic Theses and Dissertations

The Little Ice Age (LIA) was a late Holocene interval of climate cooling registered in the North Atlantic region by expansion of alpine glaciers and sea ice (Grove, 1988). Here the LIA includes an early phase from about AD 1280 to AD 1390, along with a main phase from about AD 1556 to AD 1860, followed by warming and ice retreat (Holzhauser and Zumbiihl, 1999a). It has recently been demonstrated from records of North Atlantic ice-rafted debris that the LIA is the latest cooling episode in a pervasive 1500-year cycle of the climate system that may lie at the heart …


Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix A, United States Department Of Energy Jan 1978

Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix A, United States Department Of Energy

Dickey-Lincoln School Lakes Project

The U.S. Departments of the Interior and Energy have conducted system planning, location, and environmental studies for the trans-mission facilities required for the Dickey-Lincoln School Hydroelectric Project. These studies of many alternate routes have resulted in iden-tification of a proposed transmission line route, and an environmental impact statement, as required by the National Environmental Policy Act of 1969. This report, documenting an early phase of the overall studies, was first published by the Department of the Interior in February 1977. It is being republished as Appendix A to the DOE Environmental Impact Statement for the project.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 5: Water Quality, New England Division, United States Army Corps Of Engineers Jan 1977

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 5: Water Quality, New England Division, United States Army Corps Of Engineers

Dickey-Lincoln School Lakes Project

This design memorandum presents the results of several studies undertaken to provide an understanding of present and potential future water quality conditions within and downstream from Dickey and Lincoln School Lakes in accordance with the requirements of ETL 1110-2-1402, dated 12 November 1976. Included are an examination of baseline water quality conditions and the findings of qualitative and quantitative predictive analyses performed to evaluate water quality conditions during all phases of the project's lifetime. This document will also serve as a reference for the water quality portions of the project Environmental Impact Statement.


Dickey-Lincoln School Lakes Project At Dickey, Maine : Draft Environmental Impact Statement, New England Division, United States Army Engineer Division Jan 1977

Dickey-Lincoln School Lakes Project At Dickey, Maine : Draft Environmental Impact Statement, New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

This draft EIS address the impacts of the dams and appurtenant structures. The marketing and transmission of power from Federal projects are the statutory responsibility of the Department of the Interior. Accordingly, they are conducting transmission line studies in the preparation of a draft EIS. The draft EIS for transmission line and marketing is scheduled to be submitted to the Council on Environmental Quality in February 1978. Both drafts will be combined and submitted as a Final Environmental Impact Statement in August 1978.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers Jan 1977

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers

Dickey-Lincoln School Lakes Project

This design memorandum presents for review the revised general plan and data for the Dickey-Lincoln School Lakes project, Maine, U.S.A. and Quebec, Canada to provide the basis for preparation of detailed design memoranda, plans and specifications. This document presents revisions to the basic project plan and related data included in the 1967 General Design Memorandum reflecting current water resource requirements. This memorandum serves as a functional design document and 1s presented 1n Phase II level of detail. However, 1n view of the long period of Inactivity, Phase I features have also been incorporated for continuity of project information.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 3: Hydropower Capacity And Project Economic, New England Division, United States Army Corps Of Engineers Jan 1976

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 3: Hydropower Capacity And Project Economic, New England Division, United States Army Corps Of Engineers

Dickey-Lincoln School Lakes Project

This design memorandum presents the results of current engineering and economic analyses which serve as the basis for the selection of the recommended hydro-power installation at the Dickey-Lincoln School Lakes project. The report includes a summary of data pertinent to hydropower features of the project, projections of electricity needs for the New England Power Supply Areas, a description of the recom-mended power plan and facilities, pertinent data associated with power regulation studies, and the economic and engineering rationale for capacity optimization.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada : Design Memorandum No. 2 Hydrology And Hydraulic Analysis: Section 1 - Climatology And Stream Flow, United States Army Corps Of Engineers, New England Division Jan 1967

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada : Design Memorandum No. 2 Hydrology And Hydraulic Analysis: Section 1 - Climatology And Stream Flow, United States Army Corps Of Engineers, New England Division

Dickey-Lincoln School Lakes Project

This section I is the first of four sections comprising Design Memo-randum No. 2. The other sections are: II - Dickey Dam - Spillway Design Flood, III - Lincoln School Dam - Spillway Design Flood and IV - Flood Analysis and Reservoir Regulation. la section I, hydro-logic studies will be confined generally to the drainage area of the Saint John River above the gaging station at Fort Kent, Maine. The purpose of section I is to present the climatological and streamflow data for the Saint John River above Fort Kent in order to establish hydrologic criteria for the design of …