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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.
1

The spatial analysis of the ancient funerary landscape of the Sahara Fazzan - a case study of the Wadi ash-Shati, Libya

Kgosietsile, Tshekiso January 2017 (has links)
Report submitted to the Faculty of Science, University of the Witwatersrand, in Partial fulfilment of the Requirements for Masters in Geographic Information Systems (GIS) and Remote Sensing in the Faculty of Science. School of Geography, Archaeology and Environmental Sciences, University of the Witwatersrand. March 2016. / This study is an initial attempt to investigate the spatial arrangement of graves which are believed that they can shed new light on the mortuary behaviours of ancient societies. The aim of this study is to utilise Geographic Information System (GIS) and remote sensing to document and explore the funerary landscape of the Wadi ash-Shati, Libya using a comprehensive set of environmental variables that might have influenced the spatial distribution of Garamantian funerary monuments. In view of that argument, this study is motivated by these two objectives; documenting all the Garamantian funerary monuments and settlements visible in high resolution satellite imagery and investigating their spatial patterns in their topographic setting. Spatial patterns were achieved by plotting digitised graves data from remotely sensed imagery (accessed through Google Earth) and hand held Global Positioning System (GPS) data in a GIS environment in order to extract patterns and structure in the dataset. In order to better understand these patterns and structures, the following GIS approaches; slope, elevation, visibility, clustering, directional distribution analyses were utilised. The results of the GIS analyses showed that there was correlation between graves location, qsurs or settlements, wells and with the environmental variables (slope, elevation, and distance to water resources). On the basis of the results of this research, it can be concluded that environmental variables were major factor in the placement of graves, qsurs and wells. The placement of these site locations can be related to as an expression of the socio-political, economic, cultural and ideological characteristics of the Garamantian society that created the burials and organised the Wadi ash-Shati landscape. The present study concluded that the Garamantian civilisation had established changes in the landscape that promoted the development of elaborate funerary monuments which peaked significantly during the time when aridity became immense in the study region. However additional research is necessary to provide more conclusive results and interpretations of this study, as such results from the analyses carried out should not be viewed as absolute, but as a stepping ladder for future investigation in the Wadi ash-Shati region. Keywords: GIS, Remote sensing, Funerary Landscape, Wadi ash-Shati, Libya, Spatial Analysis, Garamantian, Google Earth, Global Positioning System (GPS), Environmental Variables / LG2017
2

Spatial ecology and responses to a controlled hunt of female white-tailed deer in an exurban park

Rhoads, Craig L. January 2007 (has links)
Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Jacob L. Bowman, Dept. of Entomology & Wildlife Ecology. Includes bibliographical references.
3

Environmental variability and ecological dynamics in spatially structured populations /

Ramakrishnan, Lakshmikantan, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 50-61). Available also in a digital version from Dissertation Abstracts.
4

Spatial heterogeneity of soil nutrients, nitrogen dynamics and vegetation in a 3rd order stream floodplain in southwestern West Virginia

Dick, David Allen. January 2003 (has links)
Thesis (M.S.)--Marshall University, 2003. / Title from document title page. Document formatted into pages; contains ix, 140 p. including illustrations. Includes vita. Includes bibliographical references (p. 104-108).
5

The spatial patterning of Hieracium pilosella invaded short tussock grasslands.

Dickinson, Yvette L. January 2008 (has links)
Hieracium pilosella is an invasive weed of New Zealand's short tussock grasslands. Since the 1960s, the abundance of H. pilosella has dramatically increased; it is now thought to occur in 6 million hectares of New Zealand (Espie, 2001), predominantly in grasslands. It is at least common in 42% of this area (Espie, 2001). Ecology is inherently spatial and as plants closely interact with their direct neighbours, the spatial arrangement of plants is vital to their functioning. A handful of recently published articles have implicated spatial structure of plant communities in theories of plant competition, resource use and the invasion of plant communities. The aims of this thesis were to: 1) determine if there are consistent spatial patterns in New Zealand's short tussock grasslands at relatively small scales (i.e. spatial relationships between individuals); 2) investigate how the invasion of H. pilosella may be altering these spatial patterns; and 3) establish if the spatial patterns of species, life-forms and root systems are being altered in different ways. Spatial patterns of both tussock and inter-tussock species, life-forms and root functional groups were evaluated at a range of short tussock grassland sites across a gradient of H. pilosella invasion levels in Canterbury, using both join-count statistics and Ripley's K-function. A classification system for the root functional groups of vascular species in these communities was developed and applied. It was found that species, life-forms and root functional groups in short tussock grasslands had generally consistent spatial patterns across sites both within and between species. These patterns were variable between significantly different levels of H. pilosella ground cover. The type of spatial pattern exhibited, and the way it was altered differed between species, life-form and root functional groups. For example, tussocks exhibited increased regularity up to scales of 160 cm and increasing aggregation at scales up to 500 cm, with increases in H. pilosella abundance. In contrast, both Agrostis capillaris and herbaceous chamaephytes had increased aggregation across scales up to 160 cm. These differences in spatial patterns along the gradient of invasion are a strong indication that H. pilosella is structurally fragmenting New Zealand's short tussock grasslands. This fragmentation is likely to have far reaching effects including the disturbance of invertebrate communities and the disruption of ecosystem services including pollination, vegetation regeneration, and nutrient cycling.
6

Spatial models of forest-environment relationships on the Appalachian Plateaus the Allegheny Mountain section, western Maryland /

Kincaid, Joshua A. January 2001 (has links)
Thesis (M.A.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains vi, 43 p. : map. Includes abstract. Includes bibliographical references (p. 40-43).
7

Spatial pattern and community assembly: does the configuration of stream networks influence their community structure?

Campbell, Rebecca Elisabeth January 2011 (has links)
Dendritic stream networks are inherently spatially and hierarchically structured, but the effects of this structure on stream communities are largely unknown. My aim was to investigate spatial patterns in stream networks using extensive spatial sampling of both adult and benthic macroinvertebrates in four stream networks on the West Coast of the South Island, New Zealand. Using spatial modelling and analyses, I answered questions about appropriate spatial measurements to capture ecological processes in stream networks, metacommunity processes at different scales in space and time, and how local and regional processes interact to structure metacommunities in stream networks. Spatial eigenfunction analyses showed that distance measures that explained most variance in stream macroinvertebrate communities were stream distance and weighted stream distance measures. They performed better than Euclidean distance to measure spatial structure that is ecologically relevant to stream network communities. The spatial pattern of benthic stream macroinvertebrates was stable over time, whereas community composition changed significantly, as shown by space-time interactions modelled by MANOVA-like redundancy analysis. Thus, spatial processes structuring stream metacommunities remained constant, in agreement with neutral model predictions. Network-scale properties, particularly flood disturbances, influenced the relative importance of spatial and environmental variation in stream network metacommunities. Additionally, quantile regression indicated that three key variables, habitat size, isolation and local habitat conditions, jointly limited community structure in stream networks, providing empirical support for both island biogeography and metacommunity theories. My study indicated that spatial structuring has an important influence on stream macroinvertebrate communities. The results contribute to broader ecological theory and understanding of community assembly by relating empirical results to theoretical predictions. In particular, they advance understanding of spatial processes in stream networks. The research also highlights a number of new methods, which were successfully applied to stream systems to elucidate complex spatial patterns.
8

The spatial patterning of Hieracium pilosella invaded short tussock grasslands.

Dickinson, Yvette L. January 2008 (has links)
Hieracium pilosella is an invasive weed of New Zealand's short tussock grasslands. Since the 1960s, the abundance of H. pilosella has dramatically increased; it is now thought to occur in 6 million hectares of New Zealand (Espie, 2001), predominantly in grasslands. It is at least common in 42% of this area (Espie, 2001). Ecology is inherently spatial and as plants closely interact with their direct neighbours, the spatial arrangement of plants is vital to their functioning. A handful of recently published articles have implicated spatial structure of plant communities in theories of plant competition, resource use and the invasion of plant communities. The aims of this thesis were to: 1) determine if there are consistent spatial patterns in New Zealand's short tussock grasslands at relatively small scales (i.e. spatial relationships between individuals); 2) investigate how the invasion of H. pilosella may be altering these spatial patterns; and 3) establish if the spatial patterns of species, life-forms and root systems are being altered in different ways. Spatial patterns of both tussock and inter-tussock species, life-forms and root functional groups were evaluated at a range of short tussock grassland sites across a gradient of H. pilosella invasion levels in Canterbury, using both join-count statistics and Ripley's K-function. A classification system for the root functional groups of vascular species in these communities was developed and applied. It was found that species, life-forms and root functional groups in short tussock grasslands had generally consistent spatial patterns across sites both within and between species. These patterns were variable between significantly different levels of H. pilosella ground cover. The type of spatial pattern exhibited, and the way it was altered differed between species, life-form and root functional groups. For example, tussocks exhibited increased regularity up to scales of 160 cm and increasing aggregation at scales up to 500 cm, with increases in H. pilosella abundance. In contrast, both Agrostis capillaris and herbaceous chamaephytes had increased aggregation across scales up to 160 cm. These differences in spatial patterns along the gradient of invasion are a strong indication that H. pilosella is structurally fragmenting New Zealand's short tussock grasslands. This fragmentation is likely to have far reaching effects including the disturbance of invertebrate communities and the disruption of ecosystem services including pollination, vegetation regeneration, and nutrient cycling.
9

Spatial ecology of the Eastern diamond-backed rattlesnake (Crotalus adamanteus)

Hoss, Shannon Kelleigh, January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 68-84)
10

Effects of spatial and temporal variability of shoal habitat on stream fish assemblages in Chattahoochee tributaries, Alabama

Kennon, Ronald Adam, January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 28-35)

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