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The Effect Of Irrigation On Soil Water Availability And The Plant Water Relations Of Three Species Growing On Revegetated Bauxite Residue Disposal Areas, Sharyn Burgess Jan 2007

The Effect Of Irrigation On Soil Water Availability And The Plant Water Relations Of Three Species Growing On Revegetated Bauxite Residue Disposal Areas, Sharyn Burgess

Theses : Honours

The waste product resulting from the alumina refining process consists of residue sand and mud which is laid on bauxite residue disposal areas (RDAs). Once the RDAs have been effectively solar dried they are revegetated to minimise deep drainage and potential groundwater contamination. In this study, two RDAs located at Alcoa's Pinjarra refinery were seasonally monitored to determine the effects of irrigation on soil water availability and plant water use. Three experimental Blocks were established by Alcoa, each with an irrigated and unirrigated site. Since then, irrigation has been applied to the three treated sites to maintain the root zone …


Water Stress Vulnerability Of Four Banksia Species In Contrasting Ecohydrological Habitats On The Gnangara Mound, Western Australia, Caroline Canham Jan 2006

Water Stress Vulnerability Of Four Banksia Species In Contrasting Ecohydrological Habitats On The Gnangara Mound, Western Australia, Caroline Canham

Theses : Honours

The distribution of obligate and facultative phreatophytic vegetation reflects the gradient of ecohydrological habitats in a landscape. Preliminary investigations of Banksia vulnerability to xylem embolism have reported that obligate phreatophytes are more susceptible to water stress than facultative phreatophytes (Froend & Drake 2006). A quantitative measure of plant susceptibility to water stress is vital when establishing environmental water requirements. This study investigated interspecific differences in vulnerability to water stress for two facultative phreatophytes (B. attenuata and B. menziesii) and two obligate pln·eatophytes (B. ilicifolia and B. littoralis) at the same position along an ecohydrological gradient on the Gnangara Groundwater Mound, …


The Effects Of Light Reduction Treatments On Mobile Epifaunain An Amphibolis Griffithii (Black) Den Hartog Seagrass Ecosystem, Helen Barwick Jan 2006

The Effects Of Light Reduction Treatments On Mobile Epifaunain An Amphibolis Griffithii (Black) Den Hartog Seagrass Ecosystem, Helen Barwick

Theses : Honours

One of the main anthropogenic disturbances to seagrass meadows in Australia is reduction in light availability, through nutrient enrichment or suspended sediments. Dredging can create suspended sediment plumes from the expulsion of particulates into the water column and in tum reduces light penetration to seagrass ecosystems. Preliminary investigations have demonstrated that light reduction for different intensities and durations results in reduced seagrass and epiphytic algae biomass. The main aim of this study was to determine the effects of different intensities and durations of light reduction on epifaunal assemblages in Amphibolis griffithii seagrass meadows in Jurien Bay, Western Australia. This was …


Genetic Diversity And Gene Flow In Fragmented Populations Of The Rare Shrub, Calothamnus Sp. Whicher, Sean Stankowski Jan 2006

Genetic Diversity And Gene Flow In Fragmented Populations Of The Rare Shrub, Calothamnus Sp. Whicher, Sean Stankowski

Theses : Honours

Ca/othamnus sp. Whicher (Myrtaceae) is a narrow range endemic shrub restricted to ironstone soils near the town of Busselton in south-western Australia. Due to extensive land clearing for agriculture and mineral exploration, the species is fragmented over the majority of its range. In the present study, microsatellite markers were used to characterise levels of genetic diversity and describe levels of differentiation and gene flow among seven small, isolated road verge populations. Allelic diversity within the taxon over the six microsatellites was high (A = 17.6 ± 1.6). Diversity within populations was considerably lower (A = 5.19 ± 1.27), …


Pollen Characteristics Of Grevillea Species Determined By In Vitro Germination, Rebecca Parsons Jan 2006

Pollen Characteristics Of Grevillea Species Determined By In Vitro Germination, Rebecca Parsons

Theses : Honours

Germination of pollen in vitro is a common technique used to assess the ability of pollen to germinate under a variety of conditions. The ability to determine the viability of a pollen grain, and optimal conditions for maximum germination and storage are important for hybridisation. A means of storing pollen, while maintaining viability, enables inter-species hybridisation between species that are spatially and temporally (flowering time) separated. The ultimate aim of hybridisation is seed set and in order to increase this in a genus renowned for a very low fruit to flower ratio, maximum pollen germination must be obtained. Therefore, by …


Banksia Woodland Resilience To Groundwater Drawdown On The Gnangara Mound, Llewellyn Broun Jan 2004

Banksia Woodland Resilience To Groundwater Drawdown On The Gnangara Mound, Llewellyn Broun

Theses : Honours

Water is considered to be the major limiting resource to plant growth and survival in regions with a Mediterranean-type climate, particularly during dry summer periods when low water potentials develop (Poole et al., 1981; Miller et al., 1983-84; Mooney and Miller, 1985; Stock et al., 1992). The Swan Coastal Plain is situated within this climatic region and interactions between the climate, soil and geology has an important bearing on the water requirements of the associated Banksia woodlands (Dodd and Heddle, 1989). The assessment of the condition of any vegetative community and in this case, the resilience of Banksia woodlands to …


The Effectiveness Of Post-Fire Weed Management And The Germination Ecology Of Selected Invasive Weed Species Of Bold Park, Brett Neasham Jan 2004

The Effectiveness Of Post-Fire Weed Management And The Germination Ecology Of Selected Invasive Weed Species Of Bold Park, Brett Neasham

Theses : Honours

Bold Park is a 437 hectare A class reserve with high conservation value. Bold park is located on the Swan Coastal Plain, approximately 11 km west of the Perth CBD. Bold park is one of the few remaining coastal bushland reserves on the Swan Coastal Plain. High levels of floristic and faunal diversity contribute to Bold Park's conservation value. Weed invasion in Bold Park is reducing floristic diversity and is modifying ecosystem processes. Principle in the modified ecosystem processes is fire. While fire is a natural disturbance event in the bushland of the south-west of Western Australia, altered fire regimes …


Effects Of Temporary Par Reduction On The Seagrass Amphibolis Griffithii (Black) Den Hartog, Paul R. Mackey Jan 2004

Effects Of Temporary Par Reduction On The Seagrass Amphibolis Griffithii (Black) Den Hartog, Paul R. Mackey

Theses : Honours

Declines in seagrass health and distribution are commonly caused through human induced reductions in the availability of photosynthetically active radiation (PAR). These reductions can result from a variety of human-induced perturbations, including channel dredging. The impetus for the research was driven by the broad-scale degradation of the ecologically important southern-Australian endemic seagrass Amphibolis griffithii (Black) den Hartog in Champion Bay, Geraldton, Western Australia. The study investigated the affects of reduced PAR on A. griffithii and identified responses that may be useful in developing management triggers to minimise the impact of PAR limitation events. The study was carried out during late …


The Composition Of Cryptophytes (Geophytes) And Other Plants In The Northern Jarrah Forest Of Western Australia: An Analysis Of Logged And Old Growth Forest, Conrad C. Slee Jan 2003

The Composition Of Cryptophytes (Geophytes) And Other Plants In The Northern Jarrah Forest Of Western Australia: An Analysis Of Logged And Old Growth Forest, Conrad C. Slee

Theses : Honours

Forests are decreasing globally and there are pressing requirements for ecologically sustainable forest management to be implemented at all scales. There has been some criticism of the public managers for forests and the processes used to select reserve systems and silvicultural methods used. Limited research has been conducted on the effects of logging on the plants of the northern Jarrah forest of south western Australia, While fire is a major disturbance event, disturbance during logging operations may remove non-commercial trees, understorey shrubs and change soil conditions. Some plants that regenerate from below ground storage organs such as Cryptophytes (Geophytes) may …


Patterns Of Water Uptake And Rhizosphere Salinity In Casuarina Obesa Miq. During A Drying Period At Lake Toolibin, Western Australia, Patrick J. Mitchell Jan 2003

Patterns Of Water Uptake And Rhizosphere Salinity In Casuarina Obesa Miq. During A Drying Period At Lake Toolibin, Western Australia, Patrick J. Mitchell

Theses : Honours

Lake Toolibin is one of a few remaining freshwater lakes in the central wheatbelt of Western Australia. Since monitoring began at Lake Toolibin in the early 1970's groundwater levels have risen to within 1-2 m of the lakebed with an accompanying migration of salt. The site-specific nature of water uptake in Casuarina obesa Miq. (the dominant lakebed tree species) and rhizosphere salinity were explored spatially through analyses of soil properties (groundwater depth and salinity, particle size and components of soil water potential ψ1). Plant water sources (using δ2H signatures) and water availability (based on ψleaf …


The Fringing Halophytic Vegetation Of Lake Austin: A Study Of Mining Impacts And Vegetation Dynamics, Simone Vellekoop Jan 2002

The Fringing Halophytic Vegetation Of Lake Austin: A Study Of Mining Impacts And Vegetation Dynamics, Simone Vellekoop

Theses : Honours

Mining operations in arid regions of Western Australia are faced with many environmental management issues. One such issue is the disposal of mine water to the environment. Mine water is commonly discharged to nearby salt lakes under licence by the Department of Environmental Protection. Licence conditions dictate that the discharge water and the receiving environment be monitored to allow impacts on the environment to be detected. Salt lakes are associated with vegetation communities dominated by halophytic members of the Chenopodiaceae, While these plants are tolerant of salinity extremes, the germination stage of many species requires periods of lowered salinity. There …


The Short Term Effects Of A Fire Fighting Foam And Fire Retardant On Selected Flora From Australia's Southwest, Andrew B. Kennedy Jan 2002

The Short Term Effects Of A Fire Fighting Foam And Fire Retardant On Selected Flora From Australia's Southwest, Andrew B. Kennedy

Theses : Honours

Chemical fire suppressants arc used extensively throughout Australia's Southwest to contain and suppress wildfires. Despite several studies being conducted into their effects on terrestrial vegetation in North America and Eastern Australia, where a variety of significant effects were found, no such investigation has been carried out in Australia's Southwest. This study examined the short-term effects of a fire fighting foam and fire retardant on selected flora from Australia's Southwest. Various concentrations of fire fighting foam and fire retardant were applied to seeds and seedlings of several native species. Native species were chosen for their high abundance and widespread distribution throughout …


Invasion Of Indigenous Vegetation In South-Western Australia By Leptospermum Laevigatum (Gaertn.) F. Muell. (Myrtaceae), Anya Lam Jan 2002

Invasion Of Indigenous Vegetation In South-Western Australia By Leptospermum Laevigatum (Gaertn.) F. Muell. (Myrtaceae), Anya Lam

Theses : Honours

The current paradigm of biodiversity conservation requires the assessment of alien plant invaders, and their potential negative impacts on indigenous species and communities. Leptospermum laevigatum (Gaertn.) F. Muell. (Victorian tea tree/ Coast tea tree) is indigenous to eastern Australia. It has invaded ecosystems within its natural biogeographic range, within new ranges in Australia and overseas. The species is listed as a high priority weed in the Environmental Weed Strategy for Western Australia. However, the basis for its listing has been casual observation rather than focussed research. This study of L. laevigatum is unique in being the first to …


Salinity Tolerance Of Selected Ectomycorrhizal Fungi (Pisolithus Tinctorius Pers.) And Ectomycorrhizal Eucalypts, Ben Bradshaw Jan 2000

Salinity Tolerance Of Selected Ectomycorrhizal Fungi (Pisolithus Tinctorius Pers.) And Ectomycorrhizal Eucalypts, Ben Bradshaw

Theses : Honours

Increasing soil salinity has become a major problem worldwide. It has led to a reduction in the amount of arable land, has put at risk the supply of freshwater and threatens the existence of many natural habitats. The major increase in salinity has been attributed to human activities such as clearing of natural vegetation and large-scale irrigation programmes. The alleviation of this problem has focussed on changed management strategies. the most significant of which is the re-establishment of deep rooted plants in sail affected areas. This, however, is difficult because of the variation in salt tolerance of such plants and …


A Solid Phase Extraction System For The Isolation Of The Germination Cue In Smoky Water When Subjected To The Light Sensitive Lettuce Lactuca Sativa V. Grand Rapids, Troy David Adriansz Jan 1998

A Solid Phase Extraction System For The Isolation Of The Germination Cue In Smoky Water When Subjected To The Light Sensitive Lettuce Lactuca Sativa V. Grand Rapids, Troy David Adriansz

Theses : Honours

The search for the chemical or set of chemicals that act as a germination stimulant in Lactuca sativa v. Grand rapids (a variety of lettuce seed) was the underlying basis of this project. Through the development of a solid phase extraction (SPE) system different fractions of smoky water were tested for their effects on germination enhancement. The project targeted streamlining the amount of solvents as well as time used in past research on smoky water. Previously, several steps involving high perfo1mance liquid chromatography (HPLC), thin layer chromatography (TLC) and Gas Chromatography (GC) were employed. This project used SPE cartridges to …


The In Vitro Propagation Of Seagrasses : Halophila Ovalis, Ruppia Megacarpa And Posidonia Coriacea, Melissa Grace Henry Jan 1998

The In Vitro Propagation Of Seagrasses : Halophila Ovalis, Ruppia Megacarpa And Posidonia Coriacea, Melissa Grace Henry

Theses : Honours

Seagrass communities are of high ecological and economic significance. They provide a nursery area for commercial and recreational juvenile fish and crustacea. Seagrasses also play an important role in influencing the structure and function of many estuarine and nearshore marine environments. Unfortunately, the decline of seagrasses, as a result of human impact, has increased in recent years. This decline has become a major problem throughout the world. Current methods used to restore degraded seagrass beds are limited, the most promising being transplanting material from healthy donor beds. This approach is expensive because it is labor intensive and damages the donor …


Comparative Salt And Waterlogging Tolerance Of An Introduced Grass (Agropyron Elongatum [Host] P. Beauv.) And Two Herbaceous Australian Species (Podolepis Gracilis [Lehm.] And Danthonia Caespitosa Gaud.), Bryan William Duff Jan 1997

Comparative Salt And Waterlogging Tolerance Of An Introduced Grass (Agropyron Elongatum [Host] P. Beauv.) And Two Herbaceous Australian Species (Podolepis Gracilis [Lehm.] And Danthonia Caespitosa Gaud.), Bryan William Duff

Theses : Honours

Increasing land degradation is recognised as an immediate worldwide threat. Human induced soil salinity is probably the major cause of land abandonment, through its adverse effects on plant growth. Salinity is a major focus of environmental researchers because it is recognised that counter-strategies can potentially reclaim both artificially degraded lands and intrinsically saline areas. Currently, strategies to combat salinity require that land use is changed, since restoration to a past use is usually economically impractical or impossible. Biological strategies show most promise. Revegetation of degraded soils with hardy plant species has met with considerable success, and shows promise for the …


Effect Of Carbohydrate Source, Auxin And Endogenous Ethylene Upon Root Induction Of Eucalyptus Marginata Donn Ex Sm. In Vitro, Meredith Magaret Fairbanks Jan 1996

Effect Of Carbohydrate Source, Auxin And Endogenous Ethylene Upon Root Induction Of Eucalyptus Marginata Donn Ex Sm. In Vitro, Meredith Magaret Fairbanks

Theses : Honours

The utilisation of eucalypts around the world is increasing, mainly through the development of plantations. Clonal propagation has become important in some countries for production of such plantation trees. Micropropagation has been utilised to produce clones of trees selected for specific characteristics such as disease resistance, salt tolerance and fast growth rates. However, a suitable micropropagation protocol for all eucalypts has not been produced. One component of the micropropagation protocol, in which there is considerable difficulty, is the induction of adventitious roots on micropropagated shoots. Of particular interest, is the development of these procedures for Eucalyptus marginata (Jarrah) that have …


Phenolic And Lignin Concentration As An Indicator Of Resistance To Phytophthora Cinnamomi In Banksia Species, Sandra Jane Nicoski Jan 1996

Phenolic And Lignin Concentration As An Indicator Of Resistance To Phytophthora Cinnamomi In Banksia Species, Sandra Jane Nicoski

Theses : Honours

Phytophthora cinnamomi Rands, a soilborne fungus, is regarded as one of the most devastating pathogens yet recorded in natural ecosystems. The disease, caused by P. cinnamomi, poses an enormous threat to the flora of the southwest. The Proteaceae, in particular, contribute considerably to species richness and provide the fundamental floristic structure of many south-western plant communities. The genus Banksia, a member of the Proteaceae, is very susceptible to disease caused by P. cinnamomi. Three species, namely B. attenuata, B. grandis and B. menziesii. Were established in an aeroponics system under glasshouse conditions. Trials were conducted to optimise growing conditions in …


Development And Optimisation Of A Micellar Electrokinetic Capillary Chromatography Method For The Separation And Identification Of Phenolics From Eucalypt Species, Andrew J. Tromans Jan 1996

Development And Optimisation Of A Micellar Electrokinetic Capillary Chromatography Method For The Separation And Identification Of Phenolics From Eucalypt Species, Andrew J. Tromans

Theses : Honours

Several buffers were examined for their ability to separate a complex mixture of phenolic compounds using micellar electrokinetic capillary chromatography (MEKC). The phenolic mixture included simple phenols, phenolic acids and coumarins. Of the different buffers examined, 6 mM borate, 10 mM phosphate, 100 mM SDS, pH 8.3 gave the best separation. The ability of organic modifiers, complexation agents such as α cyclodextrin, β cyclodextrin and mixed SDS I Brij 35 micelles to improve the separation and peak retention time reproducibility of the buffer system was investigated. Baseline separation of the 18 phenolics was achieved by the 6 mM borate, 10 …


Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie Jan 1995

Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie

Theses : Honours

Each year approximately 20 million hectares of land become affected by increasing salinity. Salt tolerant plants are being used to rehabilitate salt affected areas. Plants use a variety of mechanisms to adapt to salt in their environments. Glycophytes tolerate low to moderate levels of salt while halophytes can tolerate very high salt levels. Many basic physiological attributes have been suggested as important components of a salt tolerant phenotype. These include, influx and/or efflux of ions across plasma membrane and the tonoplast, modification of membrane composition and synthesis of compatible solutes such as soluble carbohydrates, glycine betaines and proline. The project …


The Optimisation Of Nitrogen Content For Micropropagation Of Eucalyptus Marginata, Andrew James Woodward Jan 1995

The Optimisation Of Nitrogen Content For Micropropagation Of Eucalyptus Marginata, Andrew James Woodward

Theses : Honours

The use of eucalypts for plantation timber and pulp is becoming increasingly important, as are eucalypts that are resistant to disease and insect herbivory. Where clones with desirable traits have been selected, it is important that these genotypes are preserved. Micropropagation of some eucalypts, and Eucalyptus marginata in particular, can be difficult possibly due to the currently used basal medium of Murashige and Skoog (M&S)(I 962). By examining the nitrogen utilisation and the effects of medium pH of this species, it may be possible to improve general micropropagation protocol. Six clones of the species E. marginata were obtained as shoot …


The Use Of Tissue Culture For The Improvement Of Salt Tolerance In Atriplex Spp, Danielle L. Eyre Jan 1993

The Use Of Tissue Culture For The Improvement Of Salt Tolerance In Atriplex Spp, Danielle L. Eyre

Theses : Honours

Soil salinity is widespread throughout the world, and human activity is responsible for increases in the area of land affected by salt. Replanting saline areas using salt-tolerant, or halophytic, species is one method of reclaiming this land. This project investigated the possibility of using in vitro methods to select for increased salt tolerance in halophytic plants. By establishing clonal lines of halophytes in culture and screening those clones for cells exhibiting variation in their capacity to tolerate salt, it may be possible to regenerate plants with elevated salt tolerance. Clonal lines of six species of A triplex (saltbushes) were obtained. …