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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

Människan i urskogen : vegetationshistoria i Hamra nationalpark under 2500 år /

Nordström, Eva-Maria. January 2001 (has links) (PDF)
Examensarbete. / Examensarbete i biologi.
2

Spatial aggregation of vegetation parameters in a coupled land surface-atmosphere model

Arain, Muhammad Altaf. January 1994 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources) - University of Arizona. / Includes bibliographical references (leaves 148-150).
3

Vegetation characteristics expressed through transformed MODIS data : a MODIS tasseled cap /

Lobser, Sarah E. January 2004 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 77-82). Also available on the World Wide Web.
4

A comparison of change detection methods in an urban environment using LANDSAT TM and ETM+ satellite imagery a multi-temporal, multi-spectral analysis of Gwinnett County, GA 1991-2000 /

DiGirolamo, Paul A. January 2005 (has links)
Thesis (M.A.)--Georgia State University, 2005. / Title from title screen. Zhi-Yong Yin, committee chair; Paul Knapp, Truman Hartshorn, committee members. Electronic text (135 p. : col. ill., col. maps)) : digital, PDF file. Description based on contents viewed Aug. 2, 2007. Includes bibliographical references (p. 125-133).
5

A Study of Grassland Vegetation in Nanzih District, Kaohsiung

Lee, Der-Yenn 31 August 2005 (has links)
Maintaining the beauty of city grassland is an important indicator in urban landscape management for local government, and the understanding of grassland ecology is a key element to achieve this purpose. To understand and effectively manage the grassland species is the first step toward a beautiful city environment. Therefore, this study is to investigate and analyze the species composition of grassland vegetation in park, derelict urban land, green lands beside the road, and school yards in Nanzih District, Kaohsiung. The results may serve as a reference for city grassland management. The author studied the grassland vegetation at 120 sites in Nanzih District with the purpose of identifying distinct plant communities and used direct gradient analysis to analyze the relationship between environment conditions and plant communities. A total of 117 species belonging to 33 families of the vascular plants were recorded, and Poaceae is the family with the largest number of species. Six vegetation types were identified after the analyses of TWINSPAN, CA and DCA ¡G¢¹,Chamaesyce hirta - Chloris barbata type; ¢º, Panicum maximum - Bidens pilosa type; ¢», Eleusine indica - Eragrostis tenella type; ¢¼, Cynodon dactylon type; ¢½, Vernonia cinerea - Oxalis corniculata type; and ¢¾, Hedyotis corymbosa type. Results from ordination indicated that vegetation distribution patterns and soil characteristics was not closely related. Although certain relationship must existed between species and soil, the correlations between different species compositions and environmental factors were not obvious in this study.
6

Objectivity in stratification, sampling and classification of vegetation

Westfall, R. H. January 2009 (has links)
Thesis (PhD)(Botany))-Universiteit van Pretoria, 1992. / Summary in English and Afrikaans. Includes bibliographical references.
7

Plant ecology and community dynamics of machair systems in the Outer Hebrides

Owen, Nia Wyn January 1998 (has links)
The machair systems of the Outer Hebrides of Scotland are renowned for the diversity and conservation value of their plant communities. However, machair systems have a restricted distribution and are prone to disturbance from both anthropogenic and environmental sources. The effects of two major anthropogenic and environmental disturbances (agriculture and burial by wind-blown sand) on the Kildonan and Drimsdale machair systems on South Uist, and the dynamic responses of machair vegetation to these human and natural agencies were described and quantified. The investigated machair systems comprised a diversity of sand dune, grassland and marginal vegetation types which were spatially distributed along a primary environmental gradient of soil organic matter, soil moisture and soil pH. Vegetation types influenced by the effects of cultivation, notably potato-bed successions, abandoned field systems and fallow areas were also a conspicuous component of the Kildonan and Drimsdale machairs. Re-vegetation following cultivation occurred primarily through vegetative processes. Sexual reproduction via seed within different machair vegetation types was limited. The numbers of viable seeds recorded from machair seed banks ranged from 7 mˉ² soil in foredune vegetation to 58 mˉ² soil in newly-ploughed cereal land. Densities of viable seeds recorded from the machair seed rain ranged from 2 mˉ² soil in the dune slack to 24 mˉ² soil in a potato patch, fallow for two years. These values represent the first estimates of the size of machair seed budgets. Glasshouse-based burial experiments examined the effects of inundation by sand on four machair vegetation types. Foredune grassland, dune slack, three-year fallow grassland and unploughed grassland vegetation exhibited the capacity to survive and re-emerge from both intermittent and single depositions of sand. In terms of effects on plant frequency, intermittent burial by five depositions of 1cm of sand was more damaging than a single deposition of 5cm. However, all vegetation types responded to both intermittent and single burial events primarily through a change in the number of individual plants, rather than through a change in the number of plant species. Five different responses to burial by sand were identified for machair species. The suspension of photosynthetic activity and the maintenance of a low dark respiration rate were identified as important physiological responses to burial. Photosynthetic activity of machair vegetation was resumed on denudation, indicating the existence of an elastic physiological response to burial. Ecological processes in the dune slack habitat and the responses of slack vegetation to its dynamic environment were subtly different to those characterizing the other investigated sub-communities. These differences were attributed to the fact that machair slacks are characterized by an historical ecology distinct from that of other areas of the machair system. It is suggested that the formulation of effective management plans and conservation strategies for the machair systems of the Outer Hebrides ultimately lies in an understanding of their historical ecology, and in their past management and environmental histories.
8

Computer-assisted natural vegetation classification in northern Wisconsin using simulated SPOT multispectral imagery

Buchheim, Martin Paul. January 1985 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1985. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 116-131).
9

The effects of topography on mine tailing vegetation in southwest Wisconsin

Spingarn, Arthur L. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 65-67).
10

The vegetation of Swartboschkloof, Jonkershoek, Cape Province, South Africa

McDonald, David Jury January 1983 (has links)
Bibliography: leaves 111-117. / Swartboschkloof forms part of the Jonkershoek catchment complex at the headwaters of the Eerste River, Cape Province, South Africa. It has been selected for multi-disciplinary studies of Mountain Fynbos vegetation. The study area has a mainly equatorial aspect (north-facing) and receives an average of 1600 mm rain per annum, mainly in winter. Temperatures do not reach extremes. Winds blow mainly from the south-east, increasing in strength in summer. North-west winds blow intermittently in winter, bringing rain. The altitude of Swartboschkloof ranges between 285 m and 1200 m and the soils are derived from quartzitic Table Mountain Sandstone and porphyritic Cape Granite. Using the Braun-Blanquet phytosociological method, vegetation and environmental data were collected at 201 relevés throughout the study area; 101 of these relev~s are correlated with a survey of soils of part of the same area. Sixteen fynbos communities, grouped into three groups and five forest communities, grouped into two groups, have been identified. The data of a previous study by Werger, Kruger and Taylor (1972) have been interpreted in the context of this study. A map of the plant communities has been drawn and an attempt has been made to explain the distribution of the communities in terms of environmental factors. There is a strong link between the vegetation and soil geology but application of a method such as principal components analysis would be necessary to explain the relationship clearly.

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