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Full-Text Articles in Physical Sciences and Mathematics

Effects Of An Increasing Harbor Seal Population On Changes In Sites Used For Pupping, Nikolina Guldager Dec 2001

Effects Of An Increasing Harbor Seal Population On Changes In Sites Used For Pupping, Nikolina Guldager

Electronic Theses and Dissertations

Aerial survey data from 198 1 to 1997 of an increasing harbor seal (Phoca vitulina concolor) population in Penobscot and Blue Hill bays, Maine, were used to evaluate spatial and temporal patterns of use of pupping sites by mother-pup pairs. Pupping sites refer to haul-out sites where pups were observed during surveys, and are assumed to be used consistently from birth to weaning. Sites with pups were spatially clustered to remove spatial auto-correlation, reduce temporal variability and provide biologically cohesive and independent sample units. Spatial, temporal and habitat analyses were completed for 2 spatial scales: individual sites and …


Variables Influencing Nest Success Of Eastern Wild Turkeys In Connecticut: Nesting Habitat, Home Range-Scale Fragmentation, And Nest Attentiveness, Shelley M. Spohr Dec 2001

Variables Influencing Nest Success Of Eastern Wild Turkeys In Connecticut: Nesting Habitat, Home Range-Scale Fragmentation, And Nest Attentiveness, Shelley M. Spohr

Electronic Theses and Dissertations

Nest success is the most important demographic parameter influencing rates of population change of eastern wild turkeys (Meleagris gallopavo si1vestris) and many variables operating at multiple spatial and temporal scales may influence whether a nest is successful. Most studies of nest success and survival of turkeys have occurred in forested or agricultural landscapes; variables influencing nest success have not been studied in suburban landscapes. My objectives were to: 1 ) quantify survival and reproductive parameters of eastern wild turkey hens in the suburban environment of southeastern Connecticut and compare results to studies conducted in other northeastern states; 2) …


Gametogenic Cycles Of Marine Mussels, Mytilus Edulis And Mytilus Trossulus, In Cobscook Bay, Maine, Aaron P. Maloy Dec 2001

Gametogenic Cycles Of Marine Mussels, Mytilus Edulis And Mytilus Trossulus, In Cobscook Bay, Maine, Aaron P. Maloy

Electronic Theses and Dissertations

The Mytilus edulis species complex includes three smooth-shelled blue mussels, M. edulis (Linnaeus 1 75 8), M trossulus (Gould 1 850), and M galloprovincialis (Lamarck 18 19). When any two of theses species occur sympatrically, hybridization and backcrossing of hybrid and parental genotypes is evident. Despite introgression of genes between taxa their genetic integrity is maintained. To test the hypothesis that a temporal variation in species-specific spawning times is the mechanism limiting hybridization and maintaining genetic integrity in a M edulis and M. trossulus hybrid zone in eastern Maine, mussels were sampled on monthly to semi-monthly intervals throughout 2000 from …


The Role Of Water Motion In Algal Reproduction, Richard Gordon Dec 2001

The Role Of Water Motion In Algal Reproduction, Richard Gordon

Electronic Theses and Dissertations

Environmental conditions, such as water motion, can influence fertilization success and spore dispersal in marine algae. Previous studies on fucoid algae showed that gamete release is restricted to, or enhanced by, periods of low water motion. Few other algal taxa have been investigated, however, including species with an alternation of generations. I investigated gamete and spore release in the macroalgae Alaria esculenta and Ulva lactuca, as well as in the diatom Pseudo-nitachia multiseries to determine if water motion is inhibitory or stimulates propagule production and release. I used orbital shakers to simulate water motion; these were interspersed with stationary platforms …


Emersion Stress In Intertidal Seaweeds: Role Of Active Oxygen, Ian R. Davison Aug 2001

Emersion Stress In Intertidal Seaweeds: Role Of Active Oxygen, Ian R. Davison

University of Maine Office of Research Administration: Grant Reports

The study will examine stress-tolerance in two major groups of perennial intertidal macroalgae, the red and brown seaweeds. The research will test the hypothesis that active oxygen is involved in emersion stress of intertidal seaweeds. Damage due to active oxygen will be determined in stress-tolerant and stress- susceptible species exposed to emersion stress by measuring the peroxidation of membrane lipids. Plants will be grown in laboratory culture under conditions that increase their ability to withstand emersion stress. If the research hypothesis is correct, increases in stress tolerance should be associated with increased levels of antioxidants and/or protective enzymes. The proposed …


Monitoring Dioxin Levels In Maine Rivers With Semipermeable Membrane Devices, Heather A. Shoven Aug 2001

Monitoring Dioxin Levels In Maine Rivers With Semipermeable Membrane Devices, Heather A. Shoven

Electronic Theses and Dissertations

The Maine Department of Environmental Protection (DEP) currently monitors river dioxin levels through the sampling and destructive analysis of fish. Recent state law mandates that by December 31, 2002, the dioxin concentrations in fish downstream of a bleached Kraft pulp and paper mill are not to exceed the concentrations in fish upstream of the mill (38 M.R.S.A. §420-A). The objective of this thesis project was to develop an alternate method for determining Kraft mill compliance to this Dioxin law. This new method that uses semipermeable membrane devices (SPMDs) circumvents many of the concerns generated by the upstream-downstream fish test. An …


School Of Marine Sciences / Darling Marine Center, Kevin J. Eckelbarger Jul 2001

School Of Marine Sciences / Darling Marine Center, Kevin J. Eckelbarger

University of Maine Office of Research Administration: Grant Reports

Over the last six years, the University of Maine has made an unprecedented investment in its marine laboratory, the Darling Marine Center to benefit both University faculty and visiting researchers and their students. Facility improvements include many new laboratory and offices spaces, more research instrumentation, and basic support facilities such as a dining hall and new classrooms. The inauguration of a Visiting Investigation Program in 1991, the expansion of educational offerings, and the growth of a large undergraduate internship program, have resulted in a population explosion that shows no sign of abating. To set priorities for improvements, the University has …


The Response Of First And Second Order Streams To Urban Land-Use In Maine, U.S.A., Chandler Morse May 2001

The Response Of First And Second Order Streams To Urban Land-Use In Maine, U.S.A., Chandler Morse

Electronic Theses and Dissertations

Physical, chemical, and biological characteristics of streams draining 20 catchments in Maine, U.S.A were compared to determine the influence of increasing urban intensity on stream ecosystem structure. The catchments had varying levels of urban land-use (percentage of the total impervious area within the catchment) ranging from 1-31%. Stream habitat quality, stability, and water quality consistently decreased as the proportion of impervious surface area increased within the catchment. .Indices based on stream benthic macroinvertebrate communities showed even stronger declines as a function of increasing impervious area in the study catchments. Streams draining catchments with levels of impervious surfaces <6% had higher levels of both total and Ephemeroptera + Plecoptera + Trichoptera (EPT) taxonomic richness. With increased levels of urban intensity, benthic macroinvertebrate communities in streams were characterized by decreased numbers of sensitive taxa. Taxa considered to be moderately sensitive to anthropogenic stress (e.g. Acerpenna (Ephemeroptera), Paracapnia …


Ecological Implications Of Rockweed, Ascophyllum Nodosum (L.) Le Jolis, Harvesting, Jill C. Fegley May 2001

Ecological Implications Of Rockweed, Ascophyllum Nodosum (L.) Le Jolis, Harvesting, Jill C. Fegley

Electronic Theses and Dissertations

Harvesting of natural resources usually entails substantial removal of the target species. Where such species are dominant members of natural communities, their removal can have important consequences for their own regeneration as well as for the species assemblages associated with them. Rockweed is an ecologically and commercially important intertidal alga in the North Atlantic, and is increasingly being harvested in Maine. The effects of harvesting on regrowth are well known but little is known about its effects on the species that use this alga as habitat. This research focused on the ecological implications of A. nodosum harvesting on the associated …


The Foraging And Habitat Ecology Of Black Terns In Maine, Andrew Gilbert May 2001

The Foraging And Habitat Ecology Of Black Terns In Maine, Andrew Gilbert

Electronic Theses and Dissertations

The population of Black Terns in Maine is small and factors related to the ecology of this species’ foraging and habitat ecology might limit population growth and recovery. The objectives were to (1) determine if diet and provisioning rates are limiting chick growth, (2) identify and rank suitable habitat in Maine, and (3) determine if precipitation patterns and water level dynamics are limiting in Maine. I compared growth rates of chicks in 1998-2000 in Maine to rates from other studies, determined the influence of colony, year, and diet on growth rates and food deliveries and used an energetics model to …


Tb178: Methods For Evaluating Carbon Fractions In Forest Soils: A Review, Jennifer L. Evans, Ivan J. Fernandez, Lindsey E. Rustad, Stephen A. Norton Feb 2001

Tb178: Methods For Evaluating Carbon Fractions In Forest Soils: A Review, Jennifer L. Evans, Ivan J. Fernandez, Lindsey E. Rustad, Stephen A. Norton

Technical Bulletins

This publication was developed as part of an effort to evaluate the existing methodologies for determining carbon fractions in soils that might be applied to the question of forest soil C sequestration. A great deal of research has been done on this topic although often focused on agronomic soils. Forest land managers will be increasingly interested in identifying methods to monitor and to evaluate the effects of forest practices on soil C reserves. As well researchers are interested in this and the logical linkages to N cycling. Ultimately practical methods that can be widely utilized will be needed; these may …


The Chemical Mechanism Of A Brown-Rot Decay Mimtic System And Its Application In Paper Recycling Processes, Yuhui Qian Jan 2001

The Chemical Mechanism Of A Brown-Rot Decay Mimtic System And Its Application In Paper Recycling Processes, Yuhui Qian

Electronic Theses and Dissertations

This work is aimed at improving our current knowledge of the non-enzymatic inecl~anisins involved in brown-rot decay, as well as the exploration of potential applications of a brown-rot mimetic model system in paper recycling processes. The study was divided into two parts. The first part focussed on the chemical mechanisms involved in chelation and reduction of iron by a low molecular weight chelator (isolated from the brown-rot fungus Gloeophyllz~m tmbeum) and its model compound 2,3- dihydroxybenzoic acid (2,3-DHBA). Chelation as well as free radical generation mediated by this system were studied by ESR measurement. The results indicate that the effects …