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Glaciers in Flux: Interpreting the Mission and Purpose of Glacier National Park in a Warming ClimateMaureen J Wieland (8947592) 16 June 2020 (has links)
<p>This
dissertation used a qualitative and interpretive lens to explore visitor and
staff perceptions of the mission and purpose of Glacier National Park and the
National Park Service as well as the interpreted environmental state of this
park. Through the use of online survey data and participant observations, this
study provides a deeper understanding of how individuals inside of Glacier
National Park view the potential for this park to succeed or fail with its
mission as well as how environmental concerns are communicated to those within
the park during the summer of 2019. Strategic environmental communication
strategies are provided at the conclusion of this study in order to aid Glacier
and the National Park Service in more efficiently educating their publics about
their core goals and environmental management efforts.</p>
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Forest soil and vegetation characteristics in two forest types following wildfire in the Shenandoah National Park, VirginiaGroeschl, David A. 24 November 2009 (has links)
A wildfire of variable intensity occurred in mid-July of 1988 in the Shenandoah National Park and adjacent private lands. This study was established to measure post-fire forest soil and vegetation characteristics in both the mixed pine and mixed oak forest types occurring on Dovel Mountain in the Shenandoah National Park, Virginia. Vegetation and soil results represent one (1989) and two (1990) growing seasons following fire occurrence in the mixed pine forest type, whereas only second year results are reported for the mixed oak forest type.
Forest floor and mineral soil parameters differed among burn levels and followed similar trends for both forest types. Forest floor depth and weight were significantly less on low and high burn areas as compared to unburned areas. Low intensity fires removed the Oi-Oe layer while leaving the Oa layer relatively intact. Conversely, high intensity fifes resulted in the consumption of the entire forest floor. Total carbon, nitrogen, and nutrient differences between low and unburned areas for the entire forest floor (Oi-Oe + Oa) were negligible. However, loss of these constituents were much greater following high intensity fifes. Differences in the surface 10 cm of mineral soil were also detected following following high intensity fifes. Differences in the sulface 10 cm of mineral soil were also detected following low and high intensity fires. Mineral soil acidity was lower while exchangeable cation concentrations were higher in burned areas compared to unburned areas. Total carbon and nitrogen levels were higher in low burn areas, whereas total carbon and nitrogen levels were lower on high bum areas. Inorganic nitrogen levels were higher in both low and high burn areas compared to unburned areas. / Master of Science
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Mapping wetland vegetation with LIDAR in Everglades National Park, Florida, USAUnknown Date (has links)
Knowledge of the geospatial distribution of vegetation is fundamental for resource management. The objective of this study is to investigate the possible use of airborne LIDAR (light detection and ranging) data to improve classification accuracy of high spatial resolution optical imagery and compare the ability of two classification algorithms to accurately identify and map wetland vegetation communities. In this study, high resolution imagery integrated with LIDAR data was compared jointly and alone; and the nearest neighbor (NN) and machine learning random forest (RF) classifiers were assessed in semi-automated geographic object-based image analysis (GEOBIA) approaches for classification accuracy of heterogeneous vegetation assemblages at
Everglades National Park, FL, USA. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
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The Response of Zooplankton Communities in Montane Lakes of Different Fish Stocking Histories to Atmospheric Nitrogen Deposition SimulationsBrittain, Jeffrey Thomas 21 May 2015 (has links)
Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number of naturally fishless lakes and have resulted in cascading food web repercussions in aquatic and terrestrial habitats. Additional anthropogenic influences that result from increases in global airborne emissions also threaten wildlife habitat. Atmospheric nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of wilderness ecosystems. Planktonic communities have shown declines in response to predation and shifts in composition as a result of nutrient inputs and acidification, both of which are potential fates of nitrogen deposition. This study identified the response of zooplankton communities from two lakes (fish present vs. absent) in Mount Rainier National Park to manipulations simulating an episodic disturbance event in mesocosms. The experiment used a 2 x 2 factorial design with acid and nitrogen treatments. Treatments resulted in significantly elevated nitrogen and decreased pH conditions from control mesocosms over 42 days, indicating that the treatment effects were achieved. Results indicate that zooplankton communities from lakes with different food web structure respond differently to the singular effects of acid and nitrogen addition. Surprisingly, the interaction of the two stressors was related to increases in community metrics (e.g., abundance, biomass, body size, richness, and Shannon-Weiner diversity) for both lake types. This work can aid management decisions as agencies look to restore more aquatic montane habitats to their historic fishless states, and assess their abilities to recover and afford resistance to atmospheric pollution.
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A Conservation Genetic Study of Cercopithecus mitis in the Lomami Basin, Democratic Republic of the CongoUnknown Date (has links)
The Cercopithecus mitis radiation has significant phenotypic and ecological diversity, making it a great candidate for evolutionary genetic studies. This study represents the first genetic survey of C. mitis from well provenanced wild populations, including C. mitis heymansi from the TL2 landscape, an area of remote tropical forest between the Tshuapa, Lomami, and Lualaba rivers in the Democratic Republic of the Congo. Tissue samples were collected from 7 male blue monkeys, DNA was extracted and surveyed at 919 bp of the Testis-Specific Protein Y-chromosome (TSPY), and added to a larger dataset including other C. mitis and C. albogularis specimens. Evolutionary analyses suggests TL2 C. mitis shared recent genetic contact with C. albogularis at the headwaters of the Congo River than with conspecifics to the northeast, indicating the Congo River is a significant biogeographic barrier to C. mitis and sheds new light on their genetic heritage, taxonomic assignment, and conservation status. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
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Die ultrastruktuur van sperme van die rooibok Aepyceros melampus (Lichtenstein, 1812) in die Nasionale Krugerwildtuin met spesiale verwysing na die invloed van koperbesoedelingAckerman, Dirk J. (Dirk Jacobus) 08 1900 (has links)
Thesis (PhD) -- Stellenbosch University, 1995. / ENGLISH ABSTRACT: Graling in the Kruger National Park. south of Phalaborwa Gate, is contaminated with copper, probably from a nearby copper refinery. Cattle in the neighbourhood have died from copper poisoning while the average copper concentration in the livers of impala in the Krgler
National Park, was found to be abnormally high.
The possibility exists that the ultrastructure of spermatozoa may serve as an indicator of
environmental conditions. To examine this statement further, the purpose of this study
includes the following: - To describe the ultrastructure of normal impala sperm as well as their abnormalities. - To quantify the sperm abnormalities of each experimental animal and to relate the
abnormalities with the copper concentration in the impala liver, in order to determine
whether any correlation exists between these two variables.
Impala have been terminated monthly, from 1992.06.09 to 1993.05.15. in the vicinity of
Phalaborwa Gate and in the Skukuza area for other research projects. Their sperm were made available for this study. The control group consisted of 20 animals which comprised
14 animals from an area, not contaminated with copper, along the Nwaswitshaka spruit near Skukula and 6 animals originally from the same area but which had been kept in captivity at Skukuza on a diet, not contaminated with copper. The experimental group consisted of 44
animals which comprised 32 animals from copper contaminated grazing along the Tshutshi spruit south of Phalaborwa Gate and 12 animals captured along the Nwaswitshaka spruit
which were kept on a copper contaminated diet in captivity at Skukuza. Sperm from the epididymis of each animal were collected and fixed in a temporary
laboratory. The sperm were processed at the Electron Microscopy Unit of the Faculty of
Veterinary Science of the University of Pretoria and studied by means of scanning electron
microscopy (SEM) and transmission electron microscopy (TEM).
The copper concentration in the liver was analyzed and bone marrow collected of each animal
in order to determine the condition of the animal.
The external morphology of a normal impala sperm was documented by means of SEM and
the dimensions of the sperm determined. SEM micrographs of observed sperm abnormalities
were taken.
Percentages for normal sperm and the percentages of some abnormalities of a control group
(Average liver copper concentration - ALCC = 37.9 ppm WB) were calculated. The same
percentages were also calculated for an experimental group (ALCC = 104 ppm WB). The control group and the experimental group exhibited 91.6% and 93.6% normal sperm
respectively. The difference in percentage sperm abnormalities of the two groups was of the
same order. The increased copper in the livers of the experimental group has thus not lead
to an increase of the percentage macro-abnormalities observed with SEM.
The ultrastructure of normal impala sperm were described and documented with micrographs
by means of TEM. The deviations of the normal sperm ultrastructure were also recorded on
micrographs. Percentages were calculated for the normal sperm sections, as well as the
abnormalities of some sperm sections of a contrl group (ALCC = 33.86 ppm WB). The
same percentages were also calculated for an experimental group (ALCC = 122.5 ppm WB). For the control group the average percentage sperm neck sections with vacuoles was : 31.5% and for the experimental group this percentage was : 57.9%. The increased copper
concentrations in the livers of the experimental group thus led to an increase of the percentage
of sperm necks with vacuoles. There is also reason to believe that the difference of the percentages of sections of the sperm head, in the control and experimental group, should be
remarkably greater.
A graphic analysis of the TEM-data has also shown that a statistically significant correlation
exists between the percentage of sperm with vacuoles in the neck and the copper
concentrations in the livers of impalas. The conclusion is that high level copper
concentrations exert a detrimental effect on the ultrastructure of the sperm neck. The possibility also exists that copper concentrations in impala liver > 500 ppm WB. will show
a correlation with the percentages of some of the other abnormalities observed. / AFRIKAANSE OPSOMMING: Die weiding suid van Phalaborwahek in die Krugerwildtuin word waarskynlik vanaf 'n
nabygeleë kopersmeltery met koper besoedel. Van die plaasdiere in die omgewing het reeds
van kopervergiftiging gevrek en die gemiddeIde koperkonsentrasie in die lewers van
rooibokke is abnormaal hoog. Die moontlikheid bestaan dat die ultrastruktuur van spermatozoa as 'n indikator van
omgewingstoestande kan dien. Om bogenoemde moontlikheid verder te ondersoek was die
doelwit van hierdie studie die volgende: Om die ultrastruktuur van normaIe rooiboksperme en hulle abnormaliteite te beskryf en die spermabnormaliteite van elke proefdier te kwantifiseer en met die koperkonsentrasie in die
lewer in verband te bring om sodoende te bepaal of daar 'n korrelasie tussen die twee
veranderlikes bestaan.
Rooibokke wat maandeliks vanaf 1992.06.09 tot 1993.05.15 vir ander navorsingsprojekte in
die omgewing van Phalaborwahek en Skukuza getermineer is, se sperme is vir die studie
beskikbaar gestel. Die kontrolegroep het bestaan uit 20 diere wat saamgestel is uit 14 diere
afkomstig van die Nwaswitshakaspruit naby Skukuza, uit 'n gebied wat nie met koper
besoedel is nie en 6 diere uit 'n groep wat oorspronklik uit dieselfde gebied gekom het, maar wat te Skukuza in aanhouding geleef het op voedsel wat nie met koper besoedel was nie. Die
eksperimentele groep het bestaan uit 44 diere waarvan 32 in die omgewing van die
Tshutshispruit suid van Phalaborwahek versamel is en die ander 12 diere is langs die Nwaswitshakaspruit gevang en op 'n koperbesoedelde dieet te Skukuza aangehou. Sperme uit die epididymis van elke dier is in 'n tydelike laboratorium versamel en gefikseer. By die Elektronmikroskopie Eenheid van die Fakutreit van Veeartsenykunde van die
Universiteit van Pretoria is die sperme voorberei en met behulp van skandeerelektronmikroskopie (SEM) en transmissie-elektronmikroskopie (TEM) bestudeer.
Die koperkonsentrasie in die lewer is bepaal en murgvet is versamel om die kondisie van die
diere te bepaaI. Met SEM is die uitwendige morfologie van 'n normale rooiboksperm met mikrograwe
gedokumenteer en die mates van die sperm bepaal. Mikrograwe van waargeneemde
spermabnormaliteite is met SEM geneem. Persentasies is vir normale sperme en die
abnormaliteite van sommige sperme van 'n kontrolegroep (Gemiddelde lewerkoperkonsentrasie - GLKK =37.9 dpm NB) bereken. Dieselfde persentasies is ook vir
'n eksperimentele groep (GLKK = 104 dpm NB) bereken. Van die kontrolegroep het 91.6% en van die eksperimentele groep 93.6% sperme normaal vertoon. Die verskil in
persentasies spermafwykings van die twee groepe was ook van dieselfde orde. Die verhoogde
koperkonsentrasie in die lewers van die eksperimentele groep het dus nie gelei tot 'n verhoging van die persentasie makro-abnormaliteite wat met SEM waargeneem is nie.
Die ultrastruktuur van 'n normale rooiboksperm is met behulp van TEM beskryf en met mikrograwe gedokumenteer. Die afwykings van die spermultrastruktuur is ook op
mikrograwe vasgelê. Persentasies is vir die normale spermsneë en die abnormaliteite van sommige spermsneë van 'n kontrolegroep (GLKK = 33.86 dpm NB) bereken. Dieselfde persentasies is ook vir 'n eksperimentele groep (GLKK = 122.5 dpm NB) bereken. Vir die
kontrolegroep was die persentasie neksneë met vakuoles = 31.5% en vir die eksperimentele groep was die persentasie = 57.9%. Die verhoogde koperkonsentrasie in die lewer van die
eksperimentele groep het dus gelei tot 'n verhoging van die persentasie neksneë met vakuoles. Rede bestaan om te glo dat die verskil van die persentasies kopsneë van die kontrole- en eksperimentele groep ook aansienlik hoër behoort te wees. 'n Grafiese analise van die TEM-data het ook getoon dat daar 'n statisties betekenisvolle korrelasie tussen die persentasie spermnekke met vakuoles en die koperkonsentrasie in die lewer van rooibokke bestaan. Die bevinding is dat hoë lewerkoperkonsentrasies 'n nadelige invloed op die ultrastruktuur van die spermnek uitoefen. Die moontlikheid bestaan ook dat koperkonsentrasies in die lewer > 500 dpm NB ook 'n korrelasie met sommige van die ander abnormaliteite sal toon.
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Models of Bontebok (Damaliscus pygargus pygargus, Pallas 1766) habitat preferences in the Bontebok National Park and sustainable stocking ratesLuyt, Eustatius du Chavoux 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT:This study concentrates on the Bontebok (Damaliscus pygargus pygargus Pallas 1766) population
of the Bontebok National Park. Using a combination of literature research, field observations,
satellite imagery, Geographic Information System mapping and dung analysis, their habitat
preferences within the Park are ascertained and compared to different behavioural and
environmental factors. Considering vegetation composition and height, grass cover, burning history,
general topography, water availability, actual diet quality (from faecal analysis) and population
distribution, the best predictor of spatial pattern are investigated with GIS Dempster-Shafer models.
The historical density distribution of the animals in the Park can be used to predict sustainable
stocking rates. As far as possible, the results for the Bontebok are compared to those of the other
larger herbivores in Bontebok National Park i.e. Red Hartebeest, Cape Mountain Zebra and Grey
Rhebuck. These results should be useful for Wildlife Managers to know how to manage veld for
Bontebok and at what stocking rates this can be done sustainably. / AFRIKAANSE OPSOMMING: Hierdie studie fokus op die Bontebok (Damaliscus pygargus pygargus, Pallas 1766) bevolking van
die Bontebok Nasionale Park. Deur ‘n kombinasie van literatuurstudie, veldobservasies,
satlietbeelde, Geografiese Inligtingstelsel (GIS) kartering en mis-analise te gebruik, word Bontebok
habitatvoorkeure in die Park vasgestel en met verskillende gedrags- en omgewingsfaktore vergelyk.
Deur te kyk na plantegroei-samestelling en hoogte, grasbedekking, brandgeskiedenis, algemene
topografie, water-beskikbaarheid, diëet kwaliteit en die Bontebokke se waargenome ruimtelike
verspreiding, word die faktor wat die verspreidingspatroon die beste voorspel, m.b.v. GIS
Dempster-Shafer modelle ondersoek. Die historiese digtheidsverspreiding van diere in die Park
word gebruik om volhoubare veldladings te voorspel. Sover moontlik word die resultate vir
Bontebok vergelyk.met die ander groter herbivore in die Bontebok Nasionale Park, te wete Rooi
Hartebees, Kaapse Bergsebra en Vaalribbok. Hierdie resultate behoort vir Natuurlewe-bestuurders
tot nut te wees as riglyne vir veldbestuur en volhoubare veldladings van Bontebok.
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Modeling Long-Term Changes, 1958-2011, In The Reproduction And Territory Dynamics Of Bald Eagles Of Florida Bay, Southern Coastal EvergladesUnknown Date (has links)
As top-level piscivores, Bald Eagles are a compelling subject for the study of
territory dynamics and are highly representative of the distinctive suite of avian species
that occupy Florida Bay. Despite successful recovery of Bald Eagles (Haliaeetus
leuocephalus) throughout the species range, the population breeding within Florida Bay
has not mirrored this trend. Beginning in the late 1980s, Florida Bay has suffered in its
capacity to support species diversity and abundance as a result of extreme changes in
hydrology related to altered flows of incoming freshwater. In fact, Bald Eagle territory
use in Florida Bay has declined by as much as 43% as year to year variation and
sensitivity to transitions between territory states have increased. Florida Bay’s
populations of other large, conspicuous fish-eating birds, including Ospreys, Great White
Herons, Roseate Spoonbills, and Reddish Egrets each exhibit a similar pattern of decline. The effects of environmental degradation throughout Florida Bay are magnified at higher
trophic levels. The negative trend in territory occupancy is most pronounced in southeast
Florida Bay whereas effects on territory occupancy in the northwest are minimal. The
presence of spatial patterns in territory occupancy, despite regionally available breeding
birds, suggests that individuals are evaluating differences in habitat quality for which
certain territories are no longer considered viable. Building on our current understanding
of the health of this population of Bald Eagles, we have successfully implemented
modeling approaches that identify key territory breeding decisions. Loss of early
breeding season activity (occupied and active territories) despite maintaining high
breeding success indicates that changes in territory dynamics are the result of a failure to
breed and not a reproductive failure. As such, future conservation actions should
promote early breeding season activity (decisions by breeding pairs to initiate nesting) in
areas of Florida Bay that were historically occupied but are now abandoned. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
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Mechanisms Controlling Distribution of Cosmopolitan Submerged Aquatic Vegetation: A Model Study of Ruppia maritima L. (widgeongrass) at the Everglades-Florida Bay EcotoneUnknown Date (has links)
Aquatic plants and submerged aquatic vegetation (SAV) are some of the most wide-ranging species and create important habitat for fish and wildlife in many ecosystems, including highly variable coastal ecotones. Mechanistically understanding factors controlling current distributions of these species is critical to project future distribution and abundance under increasing variability and climate change. I used a population-based approach to quantify the effects of spatial and temporal variability on life history transitions of the SAV Ruppia maritima L. (widgeongrass) in the highly dynamic Everglades-Florida Bay ecotone as a model to (1) examine which life history stages were most constrained by these conditions and (2) determine how management can promote life history development to enhance its distribution, an Everglades restoration target. Ruppia maritima life history transitions were quantified in a series of laboratory and field experiments encompassing a ra nge of abiotic and biotic factors known to affect seagrass and SAV (salinity, salinity variability, temperature, light and nutrients and seed bank recruitment and competition). These studies revealed that R. maritima life history varied east to west across the Everglades ecotone, driven by multiple gradients in abiotic factors that constrained different life history transitions in distinct ways. Based on this examination, persistence of SAV populations from dynamic coastal environments is highly dependent on large reproductive events that produce high propagule densities for recruitment. Large productive meadows of SAV also depend on high rates of clonal reproduction where vegetation completely regenerates in a short amount of time. Therefore, in hydrologically variable systems, maintenance or increases in SAV reproduction is required for population persistence through recruitment. However, SAV communities that do not experience high rates of sexual reproduction are dependent on successful seed germination, seedling and adult survival and clonal reproduction for biomass production and maintenance. Seedling survival and to a lesser extent, adult survival, are bottlenecks that can limit life history transitions under highly variable hydrological conditions. To ensure long-term survival in these communities, management activities that increase survival and successful life history development through these critical stages will be beneficial. If not, SAV populations may become highly reduced and ephemeral, providing less productive habitat. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
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Old thoughts in new ideas : Tagbanua forest use and state conservation measures at Puerto Princesa Subterranean River National Park, Palawan Island, PhilippinesDressler, Wolfram Heinz January 2005 (has links)
No description available.
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