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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

Coexistence, assembly and invasion of plant communities in theory and practice

Moore, Joslin Lynley January 2000 (has links)
No description available.
2

Man and the land : an ecological history of fire and grazing on eastern Oregon rangelands /

Shinn, Dean Allison. January 1977 (has links)
Thesis (M.A.)--Oregon State University, 1978. / Typescript (photocopy). Includes bibliographical references. Also available online.
3

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.
4

Ecological survey of the grasslands of a portion of the lower south east of South Australia [with three supporting papers] /

Tiver, Newton Stanley. January 1900 (has links) (PDF)
Thesis (M.Sc.) --University of Adelaide, 1947. / Typewritten copy.
5

Spatial structure and scaling of beetle, bird and plant communities in North American grasslands

Bossenbroek, Jonathan Mark. January 2004 (has links)
Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.
6

On the assembly of a grassland plant community.

Tofts, Richard James. January 1997 (has links)
Thesis (PhD)-Open University. BLDSC no.DXN015299. / Consultation copy in 2 volumes.
7

Nesting success and population densities of grassland birds in the breeding and wintering seasons in Tennessee and Kentucky

Hinnebusch, Daniel M. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2008. / Title from title page screen (viewed on Sept. 15, 2009). Thesis advisor: David A. Buehler. Vita. Includes bibliographical references.
8

Grazing regimes and plant reproduction in semi-natural grasslands /

Wissman, Jörgen. January 2006 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2006. / Includes bibliographical references. Also available electronically via World Wide Web in PDF format.
9

Ecological effects of fire in the montane grasslands of Natal.

Everson, Colin Stuart. January 1985 (has links)
Although controlled burning has been used to manage Highland Sourveld grasslands, little was known of its effects on the vegetation. This study examined the effects of past fire treatments on veld condition, species composition, dry matter production, quality and canopy recovery growth rates of these grasslands. Also, six techniques of estimating the species composition of grasslands were compared in order to decide on a standard technique for monitoring these grasslands. From this work it was concluded that the wheel point method is the most satisfactory. Veld condition scores were significantly lower in grassland protected from fire than where veld had been burnt or burnt and grazed at regular intervals. Frequent defoliation was found to maintain the grassland composition largely unchanged over a period of 30 years. Individual species were, however, found to react strongly to defoliation frequency. Plant demographic studies were therefore carried out to explain this differential response to burning. Three Decreaser and two Increaser I species were studied. In all species examined, recruitment of secondary tillers was stimulated by regular burning, each species being well adapted to a regular fire regime. Differential responses to burning were best explained by the combined effects of the different reproductive capacities and mortality rates of tillers of these species. A biennial spring burning regime was shown to be most suitable for maintaining the most important grass species at their present levels of abundance. Annual winter and biennial spring burning did not result in significant differences in dry matter production. Maximum net productivity was approximately 230 g/m² in both treatments, placing them amongst the more productive areas of Southern Africa. Examination of canopy recovery growth rates showed that there is little difference in the percentage canopy cover at the end of the growing season when veld is burnt annually in winter or biennially in spring. However, differences in season of burn resulted in exposure to erosive forces at different times of the year. The results of this investigation have highlighted the importance of regular burning during the dormant period in the montane grasslands of Natal. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1985.
10

Juniper Effects on Grassland Soil Nutrient Availability

January 2010 (has links)
abstract: ABSTRACT The February 2008 study of a Snowflake, Arizona site measured changes in soil organic carbon, total nitrogen, extractable phosphorus, and soil moisture, to determine what affect One-seed Juniper (Juniperus monosperma) trees have on surrounding soil, thus affecting native grass growth. Increasing juniper densities in grasslands also decrease populations of some grassland bird species. Measurements were taken each meter along a twelve meter line transect, moving from juniper trees, through a bare soil area and into a grassland. Non-linear relationships were examined, in regard to distance from the tree and juniper root mass. Relationships were examined to determine any affect of the juniper tree on soil characteristics along the transect. Organic carbon decreased as distance increased from the trees (F=4.25, df=46, p=0.020). Soil moisture increased with distance from the trees (F=5.42, df=46, p=0.008), and juniper root mass, of roots less than 1 mm diameter, significantly decreased with distance away from the trees (F=11.29, df=46, p=0.0001). Total nitrogen and extractable phosphorus did not significantly change with distance from the tree, or presence of juniper roots. This data is important as grassland restoration projects rely on the availability of soil nutrients and water for reestablishment of native grass species. / Dissertation/Thesis / M.S. Applied Biological Sciences 2010

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