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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Productivity of the macrophytes of Marion Lake, B.C.

Davies, Gordon Stanley January 1968 (has links)
The in situ productivity of both the phytoplankton and the macro- phytes in Marion Lake, B.C., was determined from April 1966 through September 1966, by using ¹⁴C techniques. The uptake of NaH¹⁴CO₃ was measured in selected macrophytes by enclosing them in plexiglass chambers. These plants were then combusted in oxygen, and the ¹⁴CO₂ was absorbed in toluene-POPOP-ethanolamine. Radioassay was accomplished by liquid scintillation. In addition to the ¹⁴C method, an organic weight method was used to measure macrophytic productivity. The productivity of the macrophytes was always higher than that of the phytoplankton. There was a considerable difference in the estimates of the macrophyte productivity arrived at by the two different methods, and reasons for this are discussed. The total productivity of the lake is very low when compared with lakes of similar latitudes because of low phytoplankton productivity. It is concluded that in Marion Lake the macrophytes are more important primary producers than the phytoplankton. The difficulty of comparing data between this and other studies is discussed, and the need for standardization of methods is emphasized. / Science, Faculty of / Zoology, Department of / Graduate
22

Petrology of the Bull-of-the-Woods intrusive complex

Jackson, James Streshley 01 January 1978 (has links)
An area of unmapped intrusions lies within the Bull-of-the-Woods Roadless Area of Mount Hood National Forest. A variety of andesites, dacites,and diorites intruding units of tuff and andesite lava flows crop out over.an area of 52 sq km. These intrusions do not appear on the Geologic Map of Oregon West of the 121st Meridian (Hells and Peck, 1961). The purpose of this investigation is to map and describe these intrusions, with attention to the following questions: What is the petrographic and geochemical nature of these intrusions? What is the order of emplacement of these intrusions? What is the probable mechanism of intrusion? What relation do these intrusions bear to a possible underlying batholith? Contact relations in the field, petrographic studies, and major and trace element trends were used to address these questions.
23

The transitioning of a midwestern community's economy : how Marion's strategic planning brought about change

Hawks, Steven J. January 2007 (has links)
Through exploratory qualitative research, Marion and Grant County, Indiana, were found to employ two avenues for attracting new businesses. It was determined that elected officials focused on the business side of things, and the non-elected officials focused on what the community had to offer its potential new companies. They work on two different avenues, but their paths do come together to form one cohesive approach. Through working as a team, they have been successful at attracting businesses. The team has been successful at responding to businesses looking to relocate as well as attracting businesses through contacts, travels, trade journals, and national conventions. / Department of Sociology
24

Spatial variation in plant nutrient composition on Marion Island

Rossouw, Marius Wilhelmus 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: To estimate nutrient budgets and model nutrient cycling at a whole ecosystem level on sub-Antarctic Marion Island requires information on the spatial variability of plant nutrient concentrations on the island. The complexity of constructing budgets and models will also be reduced if, instead of considering each plant species individually, the species can be grouped on the basis of their similarities/differences in nutrient concentrations. This thesis presents the results of an investigation into both these aspects. Altitude and distance from the sea are highly correlated with each other and thus influence the concentrations of all the nutrients considered (N, P, K, Ca, Mg and Na) very similarly. Concentrations of N, P and Na in living leaves, dead leaves, stems and roots decrease going inland, due to a decline in the influence of animal manuring and of sea spray. Ca concentration increases going inland, away from the organic peats characteristic of the lowland regions toward the mineral rawmark inland soils. Declining sea spray and increasing soil minerality going inland both affect plant Mg concentration; the net effect is a slight decrease in Mg concentration going away from the coast. K concentration in living leaves and roots did not change going inland; dead leaf and stem K concentrations showed a weak decline. Bryophyte shoot nutrient concentrations do not show such marked patterns of change going inland. Considering the bryophyte species as a whole, the only significant effect is that shoot Na concentration decreases, and Ca concentration increases, going inland. Although information on nutrient concentrations in all plant organs from all four (N, E, W and S) sides of the island was available for only a few species, and in many instances the between-side effect was not significant for individual species, the pattern of between-side differences is quite clear. Living leaf N, P and Mg concentrations are higher in west side than east side plants, with south and north side plants having intermediate concentrations. Leaf K concentrations are highest on the north and lowest on the west side, with east and south side concentrations being intermediate. Leaf Ca concentrations are highest on the south side and lowest on the north side, with east and west side Ca concentrations being intermediate. Leaf Na concentration declines more sharply with distance inland on the island's western and southern sides than on its eastern and northern sides, so that closer than 450 m from the shore leaf Na concentration is higher on the west and south than on the east or north sides, but further inland than that the difference lessens. There was sufficient information for dead leaf, stem and root nutrient concentrations only for the west and east sides of the island. West-east differences in nutrient concentrations of dead leaves are the same as for living leaves. Stem and root west-east concentration differences are also similar to those for living leaves, except for P and Mg concentrations, which were similar on the two sides. All organs showed the same steeper decline in Na concentration on the west than on the east side of the island. Bryophytes show somewhat different between-side nutrient concentration patterns to the vascular plants. South side (not west) bryophytes have highest N and P concentrations but, like for the vascular plants, east side bryophytes have the lowest N and P concentrations. Also similar to the vascular plants, bryophyte K concentration is highest on the north side and lowest on the west side, although south side concentrations are nearly as high as the north side ones. Unlike the vascular plant leaves, bryophyte Mg concentration is highest on the south (not west) side and lowest on the north (not east) side, with east and west side concentrations being intermediate. South side bryophytes have highest Ca and Na concentrations, similar to the vascular plant pattern. Ordination and clustering analyses of leaf nutrient concentrations suggested five nutrient type clusters amongst the island's plant species. The clusters differ in the amount (low, moderate or high) of N, P, K and Na versus the amount of Ca and Mg. Species membership of the clusters is strongly related to what major taxonomic group (bryophyte, pteridophyte, monocot or dicot) the species belongs to, but habitat factors, especially the intensity of animal manuring, also play a role. Plant guilds compiled previously for the island and which have been suggested might prove useful for modeling nutrient standing stocks on a whole island basis associate poorly with the clusters. Where a particular guild does associate closely with a cluster it is mostly an effect of taxonomic group (the guild members are all from a single taxonomic group) or habitat (the guild members are typical for a particular habitat). It is suggested that in order to reduce the complexity and arduousness of constructing whole island plant nutrient standing stock budgets, the species should be grouped according to their taxonomy – as bryophytes, dicots, monocots, club mosses or pteridophytes (the ferns proper). Subgroups of these taxonomic groups can be constructed on the basis of habitat. Mostly, this will be necessary to distinguish plants from manured habitats from plants of the same species from unmanured ones. / AFRIKAANSE OPSOMMING: Ten einde die voedingstofvoorrade en modelvoedingstofsiklus op die sub-Antarktiese Marioneiland op 'n algehele ekosisteemvlak te raam, word inligting oor die ruimtelike variasie in plantvoedingstofkonsentrasies op die eiland benodig. Die raming van voorrade en die konstruksie van modelle sal ook minder ingewikkeld wees indien plantspesies op grond van hul ooreenkomste/verskille in voedingstofkonsentrasies gegroepeer word eerder as om elke spesie individueel te beskou. Hierdie tesis bied 'n uiteensetting van die ruimtelike variasie (hoogte, afstand van die see én kant van die eiland) in die chemiese samestelling (N, P, K, Ca, Mg en Na) van plante, en probeer die plantspesies op grond daarvan in voedingstoftipes klassifiseer. Hoogte en afstand van die see is nou verwant en beïnvloed dus voedingstofkonsentrasies op feitlik dieselfde manier. N-, P- en Na-konsentrasies in lewende blare, dooie blare, stingels en wortels neem af in die rigting van die binneland weens 'n afname in die invloed van dierebemesting en seesproei. Ca-konsentrasies styg weer namate daar vanaf die organiese veengrondkenmerke van die laagliggende streke na die mineraalryke binnelandse grond beweeg word. Sowel die afname in seesproei as die toename in grondmineraalgehalte in die rigting van die binneland beïnvloed die Mg-konsentrasie in plante; die netto uitwerking is 'n effense afname in Mg-konsentrasie namate daar wegbeweeg word van die kus. Die K-konsentrasie in lewende blare en wortels verander nie in die rigting van die binneland nie, terwyl dié in dooie blare en stingels 'n geringe afname toon. Die voedingstofkonsentrasies in briofietspruite toon egter nie dieselfde merkbare veranderingspatrone in die rigting van die binneland nie. Wat die briofietspesie in die geheel betref, is die enigste beduidende uitwerking dat die Na-konsentrasie in spruite afneem en die Ca-konsentrasie toeneem namate daar na die binneland beweeg word. Die N-, P- en Mg-konsentrasies in lewende blare is hoër by plante in die weste as in die ooste van die eiland, en plante in die suide en noorde toon tussenkonsentrasies. K-konsentrasies in blare is die hoogste in die noorde en die laagste in die weste, met tussenkonsentrasies in die ooste en suide. Ca-konsentrasies in blare is weer die hoogste in die suide en die laagste in die noorde, met tussenkonsentrasies in die ooste en weste. Aan die weste- en suidekant van die eiland toon Na-konsentrasies in blare 'n skerper afname namate daar verder van die see beweeg word as aan die ooste- en noordekant. Verskille in die voedingstofkonsentrasies van dooie blare in die weste en ooste is dieselfde as vir lewende blare. Konsentrasieverskille in stingels en wortels in die weste en ooste is ook soortgelyk aan dié in lewende blare, buiten P- en Mg-konsentrasies, wat dieselfde was aan albei kante. Alle plantorgane toon dieselfde skerper afname in Na-konsentrasies in die weste as in die ooste van die eiland. Die voedingstofkonsentrasiepatrone tussen die verskillende kante van die eiland was ietwat anders vir briofiete as vir vaatplante. Briofiete in die suide (nie die weste nie) het die hoogste N- en P-konsentrasies. Soos die vaatplante, het die briofiete in die ooste die laagste N- en P-konsentrasies. Óók soortgelyk aan die vaatplante, is die K-konsentrasie van briofiete die hoogste in die noorde en die laagste in die weste, hoewel konsentrasies in die suide bykans so hoog is as dié in die noorde. In teenstelling met die blare van vaatplante, is die Mg-konsentrasie van briofiete die hoogste in die suide (nie die weste nie) en die laagste in die noorde (nie die ooste nie), met tussenkonsentrasies in die ooste en weste. Briofiete in die suide het die hoogste Ca- en Na-konsentrasies, wat weer ooreenstem met die vaatplantpatroon. Ordinasie- en trosvormingsontledings van voedingstofkonsentrasies in blare dui op vyf voedingstoftipes onder die plantspesies op die eiland, op grond van die (klein, matige of groot) hoeveelheid N, P, K en Na teenoor die hoeveelheid Ca en Mg. Die klas waartoe 'n spesie behoort, hou sterk verband met sy hoof- taksonomiese groep (briofiet, pteridofiet, monokotiel of dikotiel), hoewel habitatfaktore (veral die intensiteit van dierebemesting) ook 'n rol speel. Die plantgildes wat voorheen vir die eiland opgestel is, toon weinig ooreenkoms met die klasse wat uit hierdie studie na vore kom.
25

An evaluation of the use of menu risk assessment as a tool in food service protection programs

Gray, Lori A. 08 May 1997 (has links)
Despite the increase in information on the causes of foodborne disease, outbreaks continue to be a major preventable public health problem. Current food service establishment inspection programs, however, are not designed to assess the potential of risk for foodborne disease and do not focus prevention efforts where food service problems are more severe. The purpose of this study was, therefore, to first, compare mean inspection scores, mean number of critical violations, and mean risk index values for high risk, moderate risk and low risk food service establishments in Marion County, Oregon. Second, the study determined if menu risk assessment can be used to identify facilities that are considered to be "high risk" facilities. The data included most recent routine inspection results that had been previously collected by local sanitarians and data collected from a Menu Risk Assessment Survey which was developed by the Virginia Department of Health. The Menu Risk Assessment Survey was administered using a stratified random design, to 400 food service managers/owners between October 1993 and December 1993 The results showed that high risk establishments had lower mean inspection scores, higher mean number of critical violations, and a smaller mean risk index value than moderate or low risk establishments. The differences were attributed to lack of manager food safety education, menu items served, and operational practices observed in the establishment. The results also showed that there were statistically significant differences (p<.05) in the mean inspection score and the mean number of critical violations of "high risk" establishments and "low risk" establishments when responses to the Menu Risk Assessment Survey were compared. For example: 1) Establishments whose managers do not have food handler's training demonstrate more critical violations than establishments with trained managers, 2) Critical violations and lower inspection scores were more likely to occur in establishments that prepared and served potentially hazardous foods, 3) Food service establishments that handle extensive amounts of potentially hazardous food and serve larger populations were more likely to have lower inspection scores and increased numbers of critical violations. Based on the results found in this research, local health departments may find the Menu Risk Assessment Survey to be a useful tool in determining high, moderate, and low risk food service establishments to focus prevention efforts where the problems are more severe and are of greater public health risk. / Graduation date: 1997
26

A Phenomenology of Incarnate Experience

Brittingham, John Thomas 01 December 2014 (has links)
Despite the burgeoning field of Contemporary Continental Philosophy of Religion and the surfeit of literature on the philosophy of the body, little discusses the connections between the religious practice and the body in any phenomenologically rigorous way. However, one might argue that the phenomenology of incarnation serves as an excellent example of the ways in which the phenomenological innovations achieved by French phenomenologists Merleau-Ponty, Levinas, Michel Henry, and Jean-Luc Marion allow for the study of both the body and the religious to be furthered. Given that the field of French phenomenology is vast, it is essential that we limit our study to but a few phenomenologists whose work is most substantially involved with the problem of incarnate experience, religious experience, embodiment, and the relation to the transcendent. Therefore, this project will proceed by way of working through phenomenology of Maurice Merleau-Ponty, Emmanuel Levinas, Jean-Luc Marion, and Michel Henry in order to explore the resources these four thinkers have for our investigation into incarnate experience. Afterwards, I will attempt to construct a phenomenology of incarnate experience, drawing from their resources and insights into potential problems in hopes of being able to move beyond the problems of "doctrinal importation" and "allusory ambiguity" and further the discourse of philosophy's encounter with religious experience.
27

A Fuzzy Rule-Based Model for Predicting Precipitation in the Marion, Illinois Station Area

Alexander, Cindy-Ann Patricia 01 August 2012 (has links)
The purpose of this paper is present the results of a developed, and implemented a Fuzzy rule based model to determine the probability of precipitation in the Marion Illinois area during the summer months. The model employs fuzzy logic and the results are compared to actual data to measure how reliable and viable this method is as an option in the precipitation prediction. Researchers, over the years, have been developing models for simulating, predicting and analyzing atmospheric phenomena, in order to accurately determine their immediate and long term effects on the environment and the quality of human life, such as in agriculture, ecosystem evolution, biodiversity, and disaster preparedness (decision support systems: drought/ warning or flash floods). To simulate global climate changes, researchers use General Circulation Models (GCMs). These have been developed using numerical weather predictions. These models are very useful for global impact studies such as global warming, but they are limited if applied to regional scenarios. This is because they are not able to neither simulate the local effects nor accurately present spatial and temporal resolutions. Continued work to improve the efficiency of these systems has led to the development of various models. Improvements have come in the form of Regional Climate Models; they have higher resolution and take into account orographic effects. These models use downscaling techniques, which bridge the gap between the global climate simulations and regional climate impact assessment. This paper presents the implementation of a fuzzy rule-based downscaling technique with specific application to the Marion, Illinois area. It shows that this method has the distinct advantage of being both computation and resource inexpensive while producing accurate information in a timely manner.
28

Production ecology of bryophyte vegetation at Marion Island (Sub-Antarctic)

Russell, Shaun January 1996 (has links)
The world's tundra regions can be considered as the last unexploited terrestrial biome on the earth's surface. Bryophytes contribute significantly to primary production and nutrient cycling in tundra habitats but received considerably less attention than the vascular plants during research for the Tundra Biome Project of the International Biological Programme in the 1970s. The IBP synthesis recognised this and called for more bryophyte production data and improved methodology in future studies. The synthesis also identitied the need for more information on within-site variability, energy/chlorophyll relationships and mineral nutrient studies where tundra bryophyte production patterns are concerned. Marion Island in the sub-Antarctic has an oceanic "tundra" type of vegetation, and the island offers the characteristics of an ideal "natural laboratory" for conducting fundamental ecological research particularly in the field of primary production and energy flow. Studies at Marion Island paralleled those of the IBP but also concentrated on the vascular component of the vegetation. Bryophytes contribute up to 60% of the biomass and 90% of plant cover in the mires that dominate the well-vegetated coastal plain of Marion Island. Following the termination of IBP research therefore it was decided to extend these studies during the 1980s by measuring growth and characterising the major factors influencing growth patterns in Marion Island bryophytes. In this thesis information is given on the physical and biotic environment of Marion Island. Data is presented on the cover, biomass, seasonal and annual production values, and turn-over rates (decomposition) of 15 bryophyte species found across the full range of habit at types at Marion Island. An analysis is also made of growth-associated variables viz. soils, climate, plant energy, chlorophyll. water and mineral nutrient contents. Production was found to be related broadly to moisture-related variables, overlain by nutrient factors in some instances. Higher absolute production figures were obtained than at other tundra sites and interesting phenological data are discussed. The results suggest that decomposition is controlled mainly by tissue degradability factors and that decomposition is more significant than production in controlling biomass accumulation. A model is given for production/decomposition patterns across the range of habitat conditions at Marion Island. Several growth measurement techniques were tested and recommendations are made concerning methodology for future bryophyte production studies. By reference to ecological data collected during the study.
29

Complex zoning in clinopyroxenes from Marion Island

Botha, Andries Eliza Johannes 16 May 2013 (has links)
Euhedral clinopyroxene mega-crystals have been retrieved from Marion Island, a volcanic island situated on an inactive transform fault near the mid oceanic ridge on Antarctic tectonic plate and part of the Prince Edward Island group. The island is considered to be the product of hotspot- related volcanism. Clinopyroxene megacrysts were sampled from the southern side of the island on a scoria cone named Pyroxene Hill. Several analytical methods including Energy Dispersive Spectrometry (EDS), Electron Probe Microanalysis (EPMA) and EPMA-mapping were utilized in investigating the zoning found within these 5-10 cm large crystals. The zoning found was “patchy”, in that it did not conform to commonly described zoning such as normal, reverse, sector or oscillatory, but rather consisted of chemically distinct areas with either diffuse or sharp boundaries, not orientated parallel to the grain boundaries or crystal lattice. The chemistry of the crystals indicates that they have formed from an evolved basaltic melt, and are likely to have crystallised at a depth of 15- 30 km. A model is postulated for the formation of these crystals in which the megacrysts crystallise rapidly from a supersaturated melt. Pre-existing crystalline material undergoes imperfect diffusion at high temperature to create a patchwork of compositional zones. Supersaturation likely requires a volatile-rich melt, which undergoes rapid degassing owing to an external trigger. The presence of a transform fault directly below Marion Island may provide a seismic trigger for such a degassing event. / Dissertation (MSc)--University of Pretoria, 2013. / Geology / unrestricted
30

Dispersal and dispersion of southern elephant seals at Marion Island

Hofmeyr, G.J. Greg (Gordon John Gregory) 09 February 2006 (has links)
This study focused on the dispersal and dispersion of southern elephant seals, Mirounga leonina, at Marion Island in relation to their natal site, and to their site of first reproduction. Movements from the natal site to terrestrial haulouts used for reproduction, and between successive reproductive sites, were defined as dispersal, while movements from the natal site to sites used for purposes other than reproduction, were defined as dispersion. Some 33000 records collected over 12 years, of haul outs at 54 different sites of 5700 tagged seals, formed the database analysed. Both male and female seals were found to use sites closer to their natal site than expected, for reproductive, moult and winter haulouts. However, breeding seals used sites closer to their site of first reproduction than their natal site, on subsequent reproductive haulouts. No difference was found between the mean distances dispersed to moult sites and to winter haulout sites, but distances of dispersal were significantly less than distances of dispersion. Female seals dispersed further than males to reproductive sites, but no difference between the sexes was apparent for moult and winter dispersion. While the number of male seals hauling out to reproduce was too small to assess the effects of various factors on the dispersal of males, a number of factors influenced the dispersion of male seals, and dispersion and dispersal of female seals. These included age, isolation of natal site, anthropogenic disturbance, natal harem size and natal harem pre-weaning mortality. A number of hypotheses are proposed to explain the reasons behind the results found, and the direction of future research concerning the movements of southern elephant seals and their choice of terrestrial environment is suggested. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / ab2013 / Zoology and Entomology / unrestricted

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