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Investigation of a scapeless form of Primula farinosa L. and related studiesArnold, Elizabeth S. January 1999 (has links)
No description available.
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The creation and maintenance of spatial heterogeneity in plant communities : the role of plant-animal interactionsEdwards, Grant R. January 1994 (has links)
No description available.
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The interaction between mountain hare (Lepus timidus) feeding ecology and establishing native woodlandRao, Shaila J. January 2001 (has links)
The establishment of native woodland in the moorland areas of upland Britain is increasing. However, there is no clear basis on which to predict either the effect of this on the ecology of the mountain hare, or the effect of mountain hare on woodland establishment. This study investigates the feeding ecology of the mountain hare, a primarily moorland inhabitant in upland Britain, in an upland landscape containing a newly established native woodland and also the potential impact that they may have on regeneration of native woodland species (Pinus sylvestris, Betula pubescens and B. pendula). The mean home range size, determined by radio-tracking, of male mountain hares was 12.1 ha and females 8.9 ha. The native woodland habitat was not preferentially selected by mountain hares in summer or winter. Faecal n-alkane and long-chain fatty alcohol analysis revealed that P. sylvestris and B. pubescens were minor components of the diet in all seasons. The diet of both male and female hares was dominated by Calluna vulgaris in winter and by grasses, sedges and rushes in summer. Annual measurements of browsing by mountain hares on P. sylvestris and B. pendula saplings at eight sites throughout Scotland, showed that on average only 5.8 % of trees sustained browsing each year. Relative hare abundance, tree density, tree species and ground vegetation height did not predict the extent of browsing damage by mountain hares. In contrast, a field-based planting experiment involving nursery grown B. pubescens saplings, had higher local hare densities and revealed that mountain hares do browse saplings extensively and that season, tree density and ground vegetation height are important in determining the extent of browsing. Seasonal habitat utilisation of the experimental plots by mountain hares fluctuated in relation to the frequency of browsing. In general, the results showed that moderate densities of mountain hares are unlikely to inhibit regeneration of native woodlands However, the likelihood of damage will increase if trees occur at high densities and if local hare density is high.
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Grazer response to fire in an African savanna: exploring the role of fires in grazing lawn formationPollard, Adrian Drew January 2016 (has links)
A dissertation submitted in fulfilment of the academic requirements for the degree of
Masters of Environmental Science, School of Animal Plant and Environmental Sciences. University of the Witwatersrand. October 2016. / Fire and grazing are important drivers of grassland composition and function in
savanna ecosystems. Fire alters the forage quality and vegetation structure, so
changing fire regimes also changes grazer utilisation of the landscape. This study
aimed to investigate how different fire regimes, specifically changes in fire size and
season of burn, influence grazer attraction as well as grazing intensity and duration
in the short-term, and further to determine how long-term fire-grazing interactions
may influence the development of grazing lawns. In the short-term experiment, fires
of three different sizes were applied in both the early dry season (EDS) and late dry
season (LDS), and periodic collection of grass height and dung count data was
conducted over a full year. Results showed that grazers were immediately attracted
to the burned areas after the fires, and that fire and grazing together can maintain a
short grazed patch for a full season. The greatest grazer visitation and grazing
pressure (shortest grass) was observed on the intermediately sized burns (5ha).
Furthermore, EDS treatments exhibited less initial grazer visitation but grass was
kept in a short state for longer than on LDS burns. LDS burns had more intense
grazing but over a much shorter time. For the long-term experiment, a long-standing
fire experiment (Experimental Burn Plots, Kruger National Park, South Africa) was
used to investigate change in grass community composition as influenced by firegrazing
interactions over a 60 year period. Historical data were used, and grass
composition data were also collected on three treatments that allowed for
comparison of communities that experienced grazing and fires repeated at different
fire frequencies and different seasons (April biennial and August annual burns), as
well as a natural fire regime (control). By investigating the change in abundance in a
few key grass species, grass ecological status classes, and grass functional guilds,
results found that grasses associated with grazing lawns (stoloniferous, ‘disturbed’)
increased in abundance, while grasses of bunch grass communities decreased, and
that this change was more pronounced on April biennial burns. The results of this
study show that small fires can act as a catalyst for grass community compositional
and structural change by attracting grazers.
Key words: Grazing lawns, fire size, fire season, pyric-herbivory, savanna. / TG2016
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Effect of nitrogen fertilization and late spring burning on diet and performance of yearling steers grazing native bluestem rangeWoolfolk, John S January 2010 (has links)
Digitized by Kansas Correctional Industries
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Comparison of buffered grazing systems for beef cattleWolfe, Charles R., January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains viii, 52 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 36-39).
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Grazing management of subterranean clover (Trifolium subterraneum L.) in South Island (New Zealand) summer dry pastures : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University /Ates, Serkan. January 2009 (has links)
Thesis (Ph. D.) -- Lincoln University, 2009. / Also available via the World Wide Web.
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Impact of a grazing management regime as an internal parasite control in sheep managed under USDA's National Organic Program a case study /O'Doherty, Bernard James. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vii, 39 p. Vita. Includes abstract. Includes bibliographical references (p. 27-29).
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Effects of longtime livestock exclusion versus grazing on the desert grassland of ArizonaCaraher, David Luther, 1937- January 1970 (has links)
No description available.
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SOME FACTORS AFFECTING VEGETATION CHANGES ON A SEMIDESERT GRASS-SHRUB CATTLE RANGE IN ARIZONAMartin, S. Clark (Samuel Clark), 1916- January 1964 (has links)
No description available.
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