Contributions to the Biology of Mulga. II. Germination

1971 ◽  
Vol 19 (1) ◽  
pp. 39 ◽  
Author(s):  
PB Preece
Keyword(s):  
Arid Zone ◽  
New South ◽  
Germination Rate ◽  
Ambient Air ◽  
Laboratory Studies ◽  
South Wales ◽  
Carbon Dioxide Concentrations ◽  
Germination Behaviour ◽  
One Year ◽  
Acacia Aneura

Investigations into the germination behaviour of seed of the widespread Australian arid zone leguminous tree Acacia aneura Benth. are described. Hardseededness has been overcome in routine laboratory studies, but attempts to understand the mechanism by which it is overcome in nature were unsuccessful. The seed germinates equally well in the dark and in the light within the temperature range 15-36°C. Temperatures between 20 and 30° are optimal for germination, and carbon dioxide concentrations up to 5 % increase the germination rate above that displayed in ambient air. A simple model has been developed which suggests that seed of this species should have been available and should have germinated in c. one year in every nine, since records began in parts of western New South Wales where mulga regeneration is absent.

Overwintering of Tranzchelia discolor in prune orchards in New South Wales

1987 ◽  
Vol 38 (5) ◽  
pp. 895 ◽  
Author(s):  
PJ Ellison ◽  
L McFadyen ◽  
PF Kable
Keyword(s):  
Leaf Litter ◽  
New South ◽  
New South Wales ◽  
Cross Infection ◽  
Infected Leaf ◽  
South Wales ◽  
One Year ◽  
Tranzschelia Discolor ◽  
Better Than

There are several ways in which Tranzschelia discolor may overwinter in prune orchards in the Murrumbidgee Irrigation Areas of New South Wales. The aecial state, cross-infection from peach and almond, twig cankers, and urediniospores on living leaves persisting through winter were considered, but were thought to be unlikely. The ability of urediniospores to survive on infected leaf litter, either on the ground under trees or lodged within the framework of trees, was studied over two winters. Urediniospore viability declined with time, but in both seasons a proportion were capable of germination in the spring. Spores exposed within the tree framework survived better than those exposed on the ground, with about 20% and less than 5% respectively remaining viable by spring. In both winters spores from litter which overwintered within the framework of the tree were able to infect prune leaves in the spring. The infectivity of spores exposed on the ground was tested in the spring of one year and infections resulted on inoculated plants. The implications of these findings for the control of the rust in prunes are discussed.

Smoke affects the Germination of Native Grasses of New South Wales

1999 ◽  
Vol 47 (4) ◽  
pp. 563 ◽  
Author(s):  
Tamara R. Read ◽  
Sean M. Bellairs
Keyword(s):  
New South ◽  
Germination Rate ◽  
New South Wales ◽  
Germination Percentage ◽  
Grass Species ◽  
Native Grasses ◽  
Environmental Stimulus ◽  
Native Grass ◽  
South Wales ◽  
Stimulation Of

The germination responses to plant-derived smoke of seeds of 20 native grass species from New South Wales, Australia, were tested under laboratory conditions. The species belonged to 14 genera including Bothriochloa, Chloris, Cymbopogon, Danthonia, Dichanthium, Digitaria, Eragrostis, Eriochloa, Microlaena, Panicum, Paspalidium, Poa, Stipa and Themeda. The interaction between smoke and husk-imposed dormancy was examined by removing the floral structures surrounding the seeds, when sufficient seeds were available. Smoke was shown to be an important environmental stimulus for breaking the dormancy of native grasses; however, the response differed considerably between different genera and between species of the same genus. For almost half of the species, smoke significantly increased the germination percentage. Panicum decompositum showed the greatest response, with germination increasing from 7.7 to 63.1% when smoke was applied. Panicum effusum had no germination in the absence of smoke, but 16.7% germination when smoke was applied. Stipa scabra subsp. scabra had germination significantly reduced by smoke from 30.2 to 19.9%. Five species had their germination rate, but not the final germination percentage, affected by smoke, and a third of the species were unaffected by smoke. For five of the species, Chloris ventricosa, Dichanthium sericeum, Panicum decompositum, Poa labillardieri and Stipa scabra subsp. falcata, this is the first report of a smoke-stimulated germination response. For those species with germination promoted by smoke, retention of the covering structures did not prevent smoke stimulation of germination. Sowing smoke-treated husked seeds is likely to be preferable as it would still promote greater germination, whereas dehusking seeds can result in the seeds being more susceptible to desiccation and fungal attack in the field. It is suggested that other grassland communities that respond to pyric conditions may also contain species that respond to smoke.

The butterfly fauna of the Griffith district, a fragmented semi-arid landscape in inland southern New South Wales

2006 ◽  
Vol 12 (2) ◽  
pp. 140 ◽  
Author(s):  
Michael F. Braby ◽  
Ted D. Edwards
Keyword(s):  
Species Richness ◽  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Wagga Wagga ◽  
Fragmented Landscape ◽  
South Wales ◽  
Butterfly Fauna ◽  
Semi Arid

Thirty-three species of butterflies are recorded from the Griffith district in the semi-arid zone of inland southern New South Wales. The butterfly community comprises the following structure: 19 species (58%) are resident; 7 (21 %) are regular immigrants; 2 (6%) are irregular immigrants; 5 (15%) are vagrants. Except for a few migratory species, most occur in relatively low abundance. Lack of similar studies elsewhere in western New South Wales precludes generalizations regarding the species richness, composition and structure of semi-arid butterfly communities. Comparison of the butterfly fauna with that from five other inland regions on the slopes and foothills of the Great Diving Range, revealed that the Griffith district is most similar in species richness and composition to that of Deniliquin and to a lesser extent Wagga Wagga and Cowra in the south, than with two regions in the higher summer rainfall area of the north of the State (Coonabarabran-Mendooran, Narrabri-Bellata). Overall, the butterfly fauna of inland New South Wales (total of 73 species, of which 49 occur in the southern regions) is depauperate compared with that recorded from the coastal/subcoastal areas east of the Great Dividing Range. Attention is drawn to the conservation significance of several vegetation types and habitat remnants in the Griffith district. Much of the native vegetation in the district has been extensively modified since European settlement due to excessive clearing for agriculture, resulting in a highly fragmented landscape for the conservation of native flora and fauna. With the exception of the lycaenid Candalides hyacinthinus Simplex, which is considered threatened locally, there is a general absence of narrow range endemic butterflies associated with mallee-heathland or mallee-woodland, possibly as a result of widespread land clearing practices of mallee vegetation in the past.

Do economic factors cause change in productivity and stability in the New South Wales arid zone?

1978 ◽  
Vol 1 (2) ◽  
pp. 200
Author(s):  
J.R. Anderson ◽  
PA Bruyn
Keyword(s):  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Economic Factors ◽  
South Wales ◽  
Western Division

A framework is suggested and explored for examining the influence of economic factors on changes in productivity and stability in the Western Division of New South Wales. The conclusion is reached that, excepting for an extraordinary peak of productivity around 1890, productivity continues to move up and down in a manner as unstable as ever. Economic factors seemingly play no clear role in influencing changes in productivity and only a slight and ambiguous role in influencing changes in stability.

Vegetation changes after fire on two land systems in arid North-west New South Wales.

1985 ◽  
Vol 7 (2) ◽  
pp. 80 ◽  
Author(s):  
WE Mulham
Keyword(s):  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Botanical Composition ◽  
Dune System ◽  
Erosion Risk ◽  
North West ◽  
South Wales

Following a sequence of favourable years in which pasture growth over much of the arid zone of Australia reached very high ievels, controlled burns were carried out on two contrasting vegetation types in the extreme north-west of New South Wales. A wheei-point apparatus was used to measure subse- quent changes in botanical composition and foliage cover over a four year period. On a pasture periodically dominated by Mitchell grass (Astrebla spp.) burning while growing conditions were favourable resulted in only a small long- term decrease in the cover of Mitchell grass. In the short-term all chenopod species were eliminated and a wider range and greater abundance of annual forbs were promoted in the following spring. On a similar area burned by wildfire in a year of low summer rainfall the response from Mitchell grass was much poorer and botanical composition of the pasture present in the following spring differed from that which developed in the spring following the controlled burn. It also differed from that of the unburnt pasture. The major differences were due to the response of forb species and are attributed to variation in seasonal rainfall. On a dune-system pasture the dominant grasses were species of Aristida and Enneapogon. These are relatively short-lived and appear to have little ability to regrow from the butt after fire. Their slow regeneration after the burn was reflected in the substantial increase in relative abundance of perennial forbs in the following autumn, and of annual forbs the next spring. Although fire appeared to have no long-term effect on the pasture it dramatically reduced tree and shrub numbers. It is suggested that during years in which abnormal quantities of Mitchell grass are present in this region, controlled burning could be a useful form of management. A mosaic of patches burnt at different times would reduce the potential for wide-scale wildfires, provide refuge areas for stock and wildlife in the event of wildfire, and promote a wider choice of plant material for grazing animals. However, in dune-systems vegetation, removal of the pasture cover and reduction of the tree and shrub density would constitute an erosion risk.

Habitat Use by Sminthopsis-Crassicaudata, Planigale-Gilesi and Planigale-Tenuirostris (Marsupialia, Dasyuridae) in Semiarid New-South-Wales

1987 ◽  
Vol 14 (4) ◽  
pp. 385 ◽  
Author(s):  
DG Read
Keyword(s):  
Regression Analysis ◽  
Habitat Use ◽  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Sympatric Species ◽  
Sminthopsis Crassicaudata ◽  
South Wales ◽  
Soil Cracks ◽  
Habitat Variables

Habitat use by Sminthopsis crassicaudata, Planigale gilesi and P. tenuirostris was investigated in the arid zone of New South Wales. All species showed considerable flexibility in habitat use at all times, and abundance was poorly predicted from easily measured parameters of the habitat. However, evidence was found for separation of microhabitat among these sympatric species. Multiple regression analysis indicated that abundance of S. crassicaudata was negatively associated with height of vegetation and the depth and density of soil cracks, and that of P. gilesi was positively associated with these habitat variables. Plant height was positively associated with abundance of P. tenuirostris and it was the only important predictor for this species. These results are discussed in conjunction with trapping records from other habitats.

Humid to Arid to Subhumid Vegetation Shift on Pilliga Sandstone, Ulungra Springs, New South Wales

1989 ◽  
Vol 32 (2) ◽  
pp. 182-192 ◽  
Author(s):  
J.R. Dodson ◽  
R.V.S. Wright
Keyword(s):  
Vegetation Cover ◽  
Vegetation History ◽  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Vegetation Shift ◽  
South Wales ◽  
Shrub Steppe ◽  
Pollen Rain ◽  
Open Forests

AbstractThe Pilliga Sandstone region of the northwest slope of New South Wales has a natural vegetation cover of sclerophyllous relatively closed to open forests with a largely heathy understorey, and a warm, subhumid and continental climate. Pollen analysis of spring-fed deposits gives a vegetation history extending from at least 30,000 yr B.P. to the late Holocene. Tree pollen became scarce after about 25,000 yr B.P. and an assemblage dominated by Chenopodiaceae, Liguliflorae, Tubuliflorae, and probably Poaceae developed. No similar assemblage is known from present pollen rain studies carried out in Australia. However, it clearly represents a treeless open shrub-steppe formation and therefore an arid or semiarid environment. The site thus provides evidence of an eastward late Pleistocene extension of the arid zone in Australia, and is the first full-glacial vegetation record between 20° and 35° latitude in Australia. The present vegetation cover did not become reestablished until the beginning of the Holocene, which raises questions about the form in which Pilliga Sandstone vegetation survived full-glacial conditions.

Major Achievement by Associate Professor Johanna Westbrook: Election to the American College of Medical Informatics as an International Fellow

2005 ◽  
Vol 34 (3) ◽  
pp. 67-67
Keyword(s):  
Medical Informatics ◽  
Health Informatics ◽  
Medical Research Council ◽  
New South ◽  
Research Work ◽  
Associate Professor ◽  
Journal Articles ◽  
South Wales ◽  
One Year ◽  
The University

Congratulations to Associate Professor Johanna Westbrook PhD, MHA, GradDipAppEpi, BAppSc (Medical Record Administration), who has been elected to the American College of Medical Informatics as an International Fellow. The Fellowship is the highest recognition possible in the health informatics discipline. Based upon peer election from current College Fellows, no more than two Fellowships are offered in any one year, and there are currently only two other Australian Fellows. This is a wonderful honour as it marks the highest peer recognition possible from the international community, reflecting Johanna's outstanding research work. Johanna is currently Deputy Director of the Centre for Health Informatics at the University of New South Wales and is an honorary Associate Professor at the School of Health Information Management at the University of Sydney. Johanna has published over 80 refereed journal articles and has received numerous research grants, the most recent of which is a National Health and Medical Research Council Project Grant of $583 000 for a study investigating the safety and effectiveness of hospital e-prescribing systems.

Production of summer crops in northern New South Wales. II. Effects of tillage and crop rotation on yields of sorghum

1992 ◽  
Vol 43 (1) ◽  
pp. 123 ◽  
Author(s):  
JF Holland ◽  
DF Herridge
Keyword(s):  
New South ◽  
New South Wales ◽  
Threshold Value ◽  
No Tillage ◽  
Tillage Practices ◽  
South Wales ◽  
Carry Over ◽  
One Year ◽  
N Fertility ◽  
Rotation Crop

Two crops of sorghum were grown in successive summer seasons at 3 sites on alkaline, black earth soils near Tamworth, New South Wales following either soyabeans, mungbeans, cowpeas, pigeonpeas, sunflowers or sorghum. Tillage practices were cultivation using a chisel plough and scarifier, and no-tillage using atrazine and glyphosate for weed control. Variation in grain yield (1.0-8.4 t/ha) was largely associated with variation in Dec.-Feb. rainfall (128-475 mm). An average of 15 kg grain/ha was produced for each mm water above the threshold value of 83 mm. At the high (Site A) and low (Site C) N-fertility sites, the rotation effect on sorghum yields was significant for one year, but did not carry over to a second sorghum crop. Cowpeas were the best rotation crop, followed by sunflowers mungbeans and soyabeans. At the low N-fertility site, sorghum following cowpeas outyielded sorghum after sorghum by 47% in the unfertilized plots and by an aExperiments to examine the effects of tillage practice and crop sequence on the production of sorghum grain in northern New South Wales are described. Two crops of sorghum were grown in successive seasons at three sites on alkaline, black earth soils near Tamworth following either soybean, mungbean, cowpea, pigeonpea, sunflower or sorghum. Tillage practices were cultivation using a chisel plough and scarifier, and no-tillage using atrazine and glyphosate for weed control. Variation in grain yield (1.0 to 8.4 t/ha) was largely associated with variation in December-February rainfall (128 to 475 mm). We calculated that an average of 15 kg/ha of grain was produced for each mm water above the threshold value of 83 rnm. At the high (Site A) and low (Site C) N-fertility sites, the rotation effect on sorghum yields was significant for one year, but did not carry over to a second sorghum crop. Cowpea was the best rotation crop, followed by sunflower, mungbean and soybean. At the low N-fertility site, sorghum following cowpea outyielded sorghum after sorghum by 47% in the unfertilized plots and by an average of 27% over all N treatments. It is likely that the increased yields of sorghum in the rotation plots resulted from higher levels of plant available N from both N2 fixation activity (legumes only) and reduced amounts of N removed with the harvested grain (particularly cowpea and sunflower). At the non-responsive, moderate-fertility Site B, water, rather than N, was limiting. Responses to no-tillage were apparent only in the very dry 1984/85 season (December to February rainfall, 42% below average). In the other three seasons, the cultivated crops outyielded the no-tilled crops or the differences between the two practices were not significant.

Dispersal of the Wild Rabbit, Oryctolagus cuniclus, at Urana in New South Wales

1982 ◽  
Vol 9 (3) ◽  
pp. 427 ◽  
Author(s):  
I Parer
Keyword(s):  
Natural Population ◽  
Significant Relationship ◽  
New South ◽  
New South Wales ◽  
Wild Rabbit ◽  
South Wales ◽  
One Year

In a natural population of rabbits, studied for 5 years, 307 dispersal movements by young rabbits were detected. Most movements occurred at the beginning of summer and more males moved than females. With the exception of one year there was no significant relationship between the ages of dispersing rabbits and the distances moved. Three rabbits, less than 1 month old, moved more than 1500 m. During a drought year the orientation of the movements was towards Lake Urana. Adult rabbits rarely changed warrens.

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