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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.
41

The status, distribution and ecology of the Klipspringer in the Kruger National Park

Kruger, Marius 05 October 2005 (has links)
The status, distribution and ecology of klipspringer were studied in the Kruger National Park. For the status and distribution, the Kruger National Park south of the Olifants River was used as the study area. Data on the status and distribution were gathered from all the ranger sections in the study area with the use of a non-sampling method, namely a systematic search. The results showed that the klipspringer population in the Kruger National Park is secure with a patchy distribution consisting of 773 individuals in the study area and a sex ratio of one male per 1.1 female. The ecology of the klipspringer was studied in a specific study area on the Nwatindlopfu spruit between Skukuza and Tshokwane where five klipspringer individuals were radio collared. The aspects covered in the study on the ecology of klipspringer, were the activities associated with environmental and vegetation related variables as well as scent-marking. It was found that vegetation is the determining factor in the habitat selection of klipspringer in the Kruger National Park, in that it provides both shelter and food. The ideal klipspringer habitat can be described as an area that has limited access to other ungulates that can attract predators. The vegetation should consist of palatable plant species that could be utilized by klipspringer, and must also provide sufficient shelter against possible danger. Klipspringer scent marks were surveyed in a specific klipspringer range in the Kruger National Park with the use of a strip transect method. Both the male and the female klipspringer scent-mark their ranges. A pair of pre-orbital glands below the eyes produces the scent. The secretion produced is a sticky milky substance that is deposited on a suitable twig. The results showed that klipspringer in the Kruger National Park scent-¬mark more frequently on the boundaries of their ranges and also more on those sides where there is another resident klipspringer group. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2005. / Animal and Wildlife Sciences / unrestricted
42

Land use change, landslide occurrence and livelihood strategies on Mount Elgon Slopes, Eastern Uganda

Mugagga, Frank January 2011 (has links)
An investigation of the relationship between the physical, pedological and anthropogenic influences on landslide occurrence on the midslopes within and outside Mt Elgon National Park was carried out. One of the landslides occurred in a protected pristine forest environment within the Park while the other two were located at sites deforested for cultivation within and outside the National Park. Field based surveys, GIS techniques and laboratory tests were used to collect and analyze the data. A household survey was undertaken to establish the main community livelihood strategies, the drivers of land use change and implications for land degradation on the mid slopes of Mt Elgon. Aerial photographs taken in 1960 and orthophoto maps formed the benchmark for the analysis of the respective land use changes between 1995 and 2006, using 30m Landsat TM and 20m SPOT MS images in IDRISI Andes GIS environment. Landslide sites were mapped using a Magellan Professional MobileMapperTMCX and terrain parameters were derived using a 15M Digital Elevation Model. A hybrid supervised/unsupervised classification approach was employed to generate land cover maps from which the areal extent of three land cover classes (agricultural fields, woodlands and forests) was calculated. Particle size distribution and atterberg limits were used to test the hypothesis that soils at the landslide sites are inherently ‘problem soils’ where slope failure can occur even without human intervention. Shear strength parameters (internal of friction and cohesion) were used calculate the slope factor of safety to ascertain slope stability at pristine and disturbed landslide sites. Results from the socio-economic survey revealed that smallholder subsistence agriculture and encroachment on the National Park resources are the main sources of livelihoods for the communities surrounding the Park. The communities also have a strong socio-cultural attachment to the National Park, as it is the source of items used during traditional rituals like circumcision. Encroachment is driven by the high population pressure and the prevalent political climate. Farmers mainly use slash and burn technique to prepare land for cultivation and those close to the National Park are reluctant to adopt appropriate farming and soil conservation practices due to the uncertainties surrounding their future on such plots. Slash and burn iii techniques were observed to accelerate various forms of erosion including rills, gullies and sheet. Soil and water conservation techniques were mainly practiced on privately owned farms. The period 1960 and 1995 was characterized by minimal land use changes and no encroachment into the designated Mount Elgon National Park. Conversely, the period 1995 – 2006 marked a significant loss of woodlands and forest cover particularly on steep concave slopes (36º – 58º) within the National Park. The land use change trends were attributed to the prevalent land politics and exponential population growth in the region. The encroachment onto the critical slopes was noted to have induced a series of shallow and deep landslides in the area. Deforestation on Mt Elgon was reported to have both onsite and offsite climate variability and implications in the form of drought, heat waves, flash floods, economic dislocation, crop failure and associated malnutrition in surrounding low lying areas. The soils on pristine and disturbed slopes contain high amount of clay (>10 percent), are fine textured (>50 percent of the material passing the 0.075mm sieve) and highly plastic. These soil attributes imply low permeability, excessive water retention and high susceptibility to expansion and sliding. The vertic nature of soils at Nametsi was confirmed by the extremely high plasticity indices (averaging 33percent), while, high liquid limits at Buwabwala (53 percent) and Kitati (59 percent) qualified the soils as vertisols which are associated with landslides. The results point to the fact that soils at landslide sites are inherently ‘problem soils’ where slope failure can occur even without human intervention. Therefore, the hypothesis that soils at three landslide sites are inherently ‘problem soils’ where slope failure can occur even without human intervention is accepted. Notwithstanding the fact that the study was focussed on mid-altitude slopes of Mt Elgon, the results are in tandem with investigations carried out earlier on the lower densely populated slopes, thus confirming the widespread nature of problem soils on Mt Elgon. There is an urgent need to control human population growth and restore forest cover on the heavily deforested steep slopes particularly within the National Park, and restrain communities from encroaching on the pristine slopes of Mt Elgon. This will be achieved if the politicians, Park Authorities and local communities jointly participate in the design and implementation of CFMs. Future research could focus on climate change implications of deforestation of Mt Elgon environments and quantification of carbon loss related to deforestation and soil degradation in the mountain environments.
43

Spiders and ants associated with fallen logs in Forillon National Park of Canada, Quebec

Varady-Szabo, Hirondelle January 2004 (has links)
No description available.
44

Landscape development for Navajo Hill of Mesa Verde National Park

Nee, Jac-ken January 2011 (has links)
Digitized by Kansas State University Libraries
45

Long-term forest monitoring program for Mammoth Cave National Park

Taylor, John Edward January 1997 (has links)
A long-term forest monitoring program was initiated at Mammoth Cave National Park (MCNP). The objectives of this project were to establish baseline data on the representative forest community types at MCNP based on dominant tree species. Permanent monitoring plots were established in different forest community types throughout the park. A total of 32 permanent plots were established for a combined sample area of 11.4 hectares. All stems larger than 5 cm dbh were measured and mapped within each permanent plot. Data on saplings were also collected. Distributions and abundances were determined for all species in permanent plots and combined for community type summaries. Stand tables were generated for four stem diameter size categories for each permanent plot. Stand analyses included calculation of values for species in four size categories.The results describe the forests of MCNP in various stages of succession. There is a trend toward increasing dominance of shade tolerant species in several of the community types. Species composition is in transition from the dry site, shade intolerant species in the canopy to shade tolerant species in the understory. Corpus f lorida, Acer saccharum, Fagus grandifolia, and Acer rubrum are prominent species in the understory and sapling layers. Early successional species continue to dominate heavily or recently disturbed locations on karst and dry upland sites. Juniperus virginiana is the dominant species in three of the seven community types sampled. The Hemlock and Beech-Maple Communities, Community Types II and VIII, appear to be maintaining their present species compositions and community structures. These are successionally "mature" forests, and include some of the most ecologically important areas of the park. However, Betula alleghaniensis is not reproducing in the Hemlock ravines community type, the only sites where this species occurs. Ailanthus altissima, an invasive exotic tree, was found in several of the areas sampled. / Department of Biology
46

Dorylaimida uit die Nasionale Krugerwildtuin

01 September 2015 (has links)
M.Sc. / This study embraces three facets, namely a checklist of all the freeliving and plantparasitic nematodes, reported from the Kruger National Park, descriptions of the nematode species found during the present study, and a historical review of the family Aporcelaimidae with emphasis on the genus Aporcelaimellus Heyns, 1965, a species compendium and descriptions of several new species ...
47

Adopting a heterogeneity paradigm for understanding and managing elephants for biodiversity : a case study in riparian woodlands in Kruger National Park

Gaylard, Angela January 2016 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2015. / Decades of study devoted to solving the “elephant problem” have generally concurred that increasing elephant populations inevitably reduce biodiversity. However, recent evidence suggests that such reductions can be accompanied by increases in other components of biodiversity, and that ultimately elephant effects are scale-dependent. Although this new perspective now underpins elephant management strategies in savannas such as the Kruger National Park (KNP), South Africa, few empirical studies in support of this strategy have incorporated the contribution of spatial context, or allowed for the emergence of relevant scales, in their interpretations of heterogeneity. Moreover, use of traditional modes of scientific enquiry and statistical approaches for investigating heterogeneity in complex systems have been challenged. Recent advances in spatial statistics, together with an alternative mode of science that draws upon multiple lines of converging evidence rather than testing narrowlyfocused hypotheses, have the potential to address these challenges. However, their practical application for understanding elephants as agents of change remains lacking. Riparian zones along the ephemeral rivers in northern KNP provided an ideal landscape to explore the spatial and temporal parameters of elephant effects in response to surface water, as a critical resource, and hence to develop a framework for a heterogeneity approach for understanding and managing elephants as agents of change in savannas.
48

A spatial model to determine the location and extent of sodic sites in the Shingwedzi and Ripape river catchments of the Kruger National Park using remote sensing classification techniques and satellite imagery

Kleyn, Linda Gail 01 February 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / Sodic soils are salt-affected soils which are high in sodium in relation to magnesium and calcium. Commonly called sodic sites in the Kruger National Park (KNP), these patches exhibit unique functional characteristics due to the high levels of sodium which cause surface crusting, cracking and the dispersion of clay particles. The aim of this study is to use satellite imagery to map sodic sites in the KNP at different spatial and spectral scales, giving the best option for a repeatable, semi-automated classification. The resultant map of sodic sites for the KNP will be used as a management tool and for future research projects. A field test for sodicity was necessary to collect sufficient ground truth samples for robust accuracy assessment of the image classification. Sodic soils are identified by measuring EC, pH and SAR which are highly variable within site and between testing methods, and therefore not useful for rapid ground truth classification of sodic soils in the field. The sodium level at which clay particle dispersion takes place varies between soils, but is measurable in the field using the Emerson dispersion test. Laboratory tested sodic soil sites from previous research re-tested in this study showed positive results for dispersion of clay particles in water. The physical properties of sodic sites described in the literature and observed in the field were applied to classify sodic sites in the KNP in the field using a decision tree, together with results from the dispersion test and the observed presence of the grass species Sporobolus iocladus. Landsat 7 and SPOT 5 imagery cover the whole park, with ASTER, CAO hyperspectral, LiDAR and black and white orthophotos available for selected areas. The topography elements of crest and footslope were derived from the STRM 90m digital elevation model (DEM). Image preprocessing to top of atmosphere reflectance was performed where necessary and visual enhancement techniques and transformations were applied to derive the normalised difference vegetation index (NDVI) and other indices. Spectral signatures were checked against spectral signature libraries, and the class separation was tested using the cluster analysis of spectral signatures. MODIS NDVI averages placed the imagery in phenological context. Object-based image analysis using eCognition was applied to classify the sodic sites of the Shingwedzi and Ripape River catchments. The input imagery was segmented into ecologically meaningful patches and classification accuracy was assessed using the field samples collected using the decision tree to identify four classes: sodic sites (bare and woody), river sand, riverine vegetation and savanna areas. Comparison of the accuracy assessments for the Shingwedzi study site showed that the Landsat 7 and SPOT 5 classification algorithms gave an overall kappa index accuracy of 89% and 78% respectively, and a sodic site kappa index of 90% and 89%. Validation results using the ground truth samples gave an overall kappa index accuracy of 61% for Landsat 7 and 52% for SPOT 5, with a sodic site kappa index of 49% and 39% respectively. The classification algorithms were applied to the Ripape study site for Landsat 7 and SPOT 5 with repeatable results for the SPOT 5 imagery of 88% overall kappa index and 81-93% kappa index for sodic sites using similar seasonal imagery in the wet to early dry season. The Landsat 7 classification algorithm was applied to the entire KNP based on the repeatability results of 56% overall kappa index and 60% sodic site kappa index for the Ripape site. The quest for a repeatable algorithm to classify sodic sites from satellite imagery has been met by the SPOT 5 imagery using scenes acquired at similar seasonal stages. The late wet season or early dry season imagery was used to apply the classification algorithm with the best success. Changes in size or shape of sodic sites over time requires very high resolution imagery and further studies to understand where the edge of sodic sites are detected from imagery, and how the phenology of the vegetation growing on these sites affects detecting any change in size of the sodic site.
49

The epidemiology and etiology of visitor injuries in Hawaii Volcanoes National Park

Heggie, Travis Wade 12 April 2006 (has links)
The U.S. National Park Service has recognized visitor health and safety as an important component of protected area management. Despite this recognition, research investigating visitor health and safety issues in national parks is lacking. In order to improve the understanding of the factors contributing to visitor injuries, the purpose of this study was to: 1) identify the distribution of injuries in Hawaii Volcanoes National Park, 2) examine the relationship between visitor factors and the severity of visitor injuries in Hawaii Volcanoes National Park, 3) examine the relationship between environmental factors and the severity of visitor injuries in Hawaii Volcanoes National Park, and 4) determine the effectiveness of sign placement and indirect supervision on controlling visitor injuries in the park. Data for this study consisted of 5,947 incident reports recorded in Hawaii Volcanoes between January 1, 1993 and December 31, 2002. The results found that even though 26% of the injuries in the park occur in frontcountry regions, 53% of all visitor injuries took place at the Eruption Site. As well, 130 of the 268 (49%) fatalities occurred on roadway environments and 1,179 of the 1,698 (69%) severe injuries occurred at the Eruption Site. Logistic regression analysis used to examine the relationship between visitor factors and injury severity in Hawaii Volcanoes National Park found that female visitors, visitors wearing minimal footwear and clothing, and visitors carrying no flashlight and minimal drinking water are factors significantly associated with fatal injuries. Visitors wearing minimal footwear and clothing, visitors carrying no flashlight and minimal drinking water, visitors entering restricted areas, visitors with pre-existing health conditions, and visitors aged 50-59 years of age are factors significantly associated with severe injuries. Logistic regression analysis found no built environment factor to be significantly associated with visitor fatalities or severe injuries. However, darkness and rugged terrain were significantly associated with visitor fatalities. Chi-square tests of independence found the combined treatment of sign placement and indirect supervision to have no effect on reducing the frequency and severity of visitor injuries at the Eruption Site.
50

Subalpine revegetation on backcountry campsites near Tuolumne Meadows, Yosemite National Park, California : third year results

Moritsch, Barbara J. 27 April 1992 (has links)
The National Park Service initiated a backcountry campsite restoration project in 1987 to restore native vegetation on severely degraded campsites in three subalpine lake basins in Yosemite National Park. Restoration treatments included soil scarification, transplanting, manual seeding and site protection. Eight of the treated campsites were monitored in 1990 to evaluate changes in percent vegetation cover, species richness and volunteer establishment that had occurred over the three year period beginning prior to treatment application in the summer of 1987, and ending in the summer of 1990. Percent vegetation cover increased slightly across all sampled quadrats ([mean] = 0.71; N = 214) with mean percent cover changes ranging from -0.37 to 4.36 on individual campsites. Three sites had a loss of cover. Percent cover changes differed most among campsites within lake basins. Changes in percent cover did not differ among lake basins or impact strata (barren core, moderately trampled, and peripheral). Transplanting did not appear to be an important influence on changes in percent cover, as cover changes did not differ between planted and unplanted areas. Survival of transplants planted in 1987 was poor (19.2%), but survival of transplants planted in 1988 was higher (70.5%). Species richness increased slightly across all sampled quadrats ([mean] = 0.54 species per quadrat), with species richness changes on campsites ranging from -0.13 to 1.75 species per quadrat. One site had a mean decrease in species richness. Species richness changes differed among campsites, with the largest increases occurring on those campsites that also had the greatest increases in percent cover. Changes in species richness also differed among impact strata, with the largest increases occurring on barren core areas. There were small differences among lake basins, and species richness changes did not differ between planted and unplanted areas. Volunteer establishment occurred on all treated sites. The number of volunteers per site ranged from one to 45, and 29 species were represented. Individual quadrats had from one to four volunteers. Approximately 50% of the volunteers were producing seed, and overall vigor among volunteers was good. Numbers of volunteers per quadrat differed most strongly among campsites. Slight differences were detected among lake basins and impact strata, with numbers decreasing from barren core to peripheral quadrats. Differences in numbers of volunteers per quadrat between planted and unplanted areas were not detected. Soil scarification may enhance increases in cover, species richness and numbers of volunteers. However, the influence of scarification was tested on two sites only, and further study is recommended. The recovery process appeared to be strongly affected by factors operating at the campsite level. For example, sites with the greatest increases in percent cover also had the greatest increases in species richness and the most volunteers. These sites had coarse soils, relatively abundant sunlight and moisture, and were effectively protected from trampling after site treatment. Results indicate revegetation prescriptions should be made on a site-by-site basis. The performances of eleven species used in transplanting or occurring as volunteers were evaluated. Five species, Agrostis humilis, Calamagrostis breweri, Muhlenbergia filifonnis, Trisetum spicatum, and Calyptridium umbellatum show potential as colonizers in unassisted revegetation and may be useful in manual seeding treatments; three species, Calamagrostis breweri, Carex rossii, and Juncus panyi show potential for transplanting and nursery propagation; and two species, Carex spectabilis and Carex straminiformis, require further study to determine their effectiveness in subalpine revegetation treatments. / Graduation date: 1993

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