Includes bibliographical references (leaves 105-121) / x, 121, [39] leaves : ill., maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the palatability variation in Atriplex vesicaria Heward ex Benth. (bladder saltbush). The main aim of the research was to examine the idea that the sex phenotypes of this species differ in their palatability to sheep, and to characterise some of the temporal and spatial features of the phenomenon. Intensive small-plot dietary trials, supported by a paddock dietary experiment, cross-fence comparisons and cafeteria trials, showed that sheep preferentially grazed female saltbushes over male and bisexual ones. Sheep avoided male saltbushes due to a chemical deterrent, and used visual (male flower spike) and olfactory cues to detect male plants. The effect of this selective grazing was to reduce the size and reproductive output of female shrubs. Sheep also tended to return to shrubs they had grazed previously. In the semi-arid regions of South Australia, where bladder saltbush is grazed year-round, physical protection is recommended to maximise survival and reproductive output of heavily grazed shrubs. / Thesis (Ph.D.)--University of Adelaide, Depts. of Environmental Science & Management and Botany, 1999?
Identifer | oai:union.ndltd.org:ADTP/260579 |
Date | January 1998 |
Creators | Maywald, Dionne Lee |
Source Sets | Australiasian Digital Theses Program |
Language | en_US |
Detected Language | English |
Page generated in 0.0014 seconds