Selection of Grasses With Different Carbon Assimilation Pathways Under Different Sheep Stocking Pressures.

1993 ◽  
Vol 41 (3) ◽  
pp. 327 ◽  
Author(s):  
RW Rogers

The path of carbon assimilation was noted for 30 common grasses from unfertilized sheep pastures of the Northern Tablelands of New South Wales. These grasses were then grouped according to their susceptibility to stocking pressure and the frequency and relative frequency of 16 of these related to apparent intensity of stocking about a sheep camp. C3 grass frequency was independent of stocking pressure, but under heavy stocking introduced C3 species replaced native C3 species. C4 NADME species showed an increase in occurrence under high stocking rates, whereas C4 NADPME species showed a decrease in occurrence under high stocking intensity. It is suggested that response to grazing may have been a factor in the evolution of different pathways of carbon assimilation.

1978 ◽  
Vol 1 (2) ◽  
pp. 106 ◽  
Author(s):  
DL Michalk ◽  
PK Herbert

A study of the density and basal diameter of Chloris acicularis Lindl. (syn. Enteropogon acicularis (LindlJLazar. - curly windmill grass) and C. truncata R. Br. (windmill grass) was made at two stocking rates over a period of eight years. The propor- tion of ground covered by these Chloris species varied widely with season, and to a lesser extent with grazing pressure. The density of both species increased in good seasons, while the mean diameter decreased because of the number of new seedlings. Although C. truncata seedlings were more numerous in good seasons, they did not survive as well as did C. acicularis seedlings during prolonged dry periods.


1992 ◽  
Vol 14 (2) ◽  
pp. 214 ◽  
Author(s):  
RL Pressey

Information on the features to be protected in a system of conservation reserves is an obvious requirement. The quality of the data base will primarily determine the effectiveness of conservation planning in protecting the full range of natural features in a region. However, the way in which data are used to make decisions on the locations of protected areas is also critical. Rigorous procedures for reserve selection can make the difference between achieving reservation goals or not. Research on reserve selection in New South Wales over recent years has concerned both data bases and procedures for guiding decisions. Reserve planning in many regions is based largely on some form of land classification like vegetation types or land systems. There are good reasons for using such land classes to guide the selection of reserves and to judge their representativeness. Nevertheless, they can have considerable limitations as a basis for protecting all the species in a region. These limitations are reviewed with references to more detailed discussions of particular issues. The paper also reviews a variety of procedures for selecting reserves which have been tested and applied in New South Wales. Some of the recent procedures are conceptually simple but very useful in identifying the requirements of reservation goals and demonstrating the options available to planners for representing particular features. Three principles are proposed which should underpin any attempt at systematic conservation planning.


Sexual Health ◽  
2005 ◽  
Vol 2 (4) ◽  
pp. 251 ◽  
Author(s):  
Marcus Y. Chen ◽  
Basil Donovan

Background: Over the last decade, significant advances have occurred in the area of chlamydia diagnostics. The relative frequency of different testing methods employed in the diagnosis of Chlamydia trachomatis infection in New South Wales has not been previously reported. Methods: Testing methods—both laboratory method and specimen type—employed in the diagnosis of chlamydia cases notified in New South Wales between 1999 and 2002 were collated from Health Department records. Results: During a period of increasing notifications, the proportion of men diagnosed with C. trachomatis using nucleic acid tests (NATs) increased from 36% in 1999 to 90% in 2002. Among women, the proportion diagnosed using NATs increased from 42% in 1999 to 92% in 2002. Urine samples were consistently used in the diagnosis of two-thirds of the men, and one-third of the women. Conclusion: Between 1999 and 2002, a rapid shift towards NATs for genital C. trachomatis took place in New South Wales.


1988 ◽  
Vol 28 (1) ◽  
pp. 53 ◽  
Author(s):  
WH Johnston

The palatability of 20 accessions of E. curvula collected from naturalised populations in New South Wales was compared on 7 occasions with 2 selected accessions previously found to be highly palatable. The experiment was conducted at Wagga Wagga, N.S.W., between January 198 1 and July 1983. The relative palatability of most accessions was substantially similar from rating to rating, despite differences in the extent to which the trial was grazed. Palatability was related to the agronomic group to which the accessions belonged. For the naturalised taxa, Curvula was ranked equal to Tall Chloromelas. but both were more palatable than Short Chloromelas. The naturalised accessions were all less palatable than the selected accessions. It was concluded that the selected accessions were sufficiently palatable to be well utilised in pastures by stock grazing at commercial stocking rates.


1980 ◽  
Vol 2 (2) ◽  
pp. 208 ◽  
Author(s):  
RD Graetz

Plant population data for the pass white-top (Danthonia caespitosa) and for bladder saltbush (Atriplex vesicaria) were collected for four years from a pasture continuously grazed by either cattle or sheep (at equivalent stocking rates) at a site near Booligal, New South Wales. During the four years of the experiment the cattle and sheep had different Impacts on the grass and scrub components of the pasture Sheep tended to deplete the numbers of pass plants far more than did cattle, whereas saltbush shrub numbers here little affected by either type of stock. The rainfall pattern experienced throughout the experiment had a far greater influence on the survival of both grass and shrub than did grazing.


2008 ◽  
Vol 65 (4) ◽  
pp. 687-696 ◽  
Author(s):  
Douglas Rotherham ◽  
Matt K. Broadhurst ◽  
Charles A. Gray ◽  
Daniel D. Johnson

Abstract Rotherham, D., Broadhurst, M. K., Gray, C. A., and Johnson, D. D. 2008. Developing a beam trawl for sampling estuarine fish and crustaceans: assessment of a codend cover and effects of different sizes of mesh in the body and codend. – ICES Journal of Marine Science, 65: 687–696. An experiment was carried out in the Clarence River (New South Wales, Australia) to test the hypotheses that fish and crustacean catches in an experimental beam trawl were affected by a codend cover and the sizes of mesh in the body and codend. The cover had no obvious effects on the catches retained in the codend. Similarly, in comparisons between trawl bodies made from 26- and 41-mm diamond-shaped mesh, there were no differences in the assemblages of fish caught, or in the mean numbers entering the codends. For one species of fish (Acanthopagrus australis), however, there were differences in the proportions caught between the trawl bodies across different size classes. There was also some evidence to suggest that mesh size in the body of the trawl influenced the size selection of school prawns (Metapenaeus macleayi). For most finfish, there were no differences in catches between codends made from 20-mm and from 29-mm mesh hung on the bar (i.e. square-shaped mesh). In contrast, mesh size in the codend was important for the size selectivity of school prawns, with smaller carapace lengths at 50% retention in the 20-mm codend. We conclude that use of a 41-mm mesh in the body and a 20-mm square mesh in the codend of the beam trawl would be appropriate for future sampling with this gear in estuaries of New South Wales. A similar experimental approach to ours is needed in adapting the beam trawl to estuaries in other parts of the world, or in developing other types of research trawl.


2006 ◽  
Vol 12 (4) ◽  
pp. 261 ◽  
Author(s):  
S. J. S. Debus

I studied the selection of breeding habitat and nest microhabitat in Scarlet Robins Petroica multicolor and Eastern Yellow Robins Eopsaltria australis, in remnant woodland on the New England Tablelands of New South Wales in 2000?2002. Yellow Robins used breeding territories (n = 10) with significantly higher densities of rough-barked saplings, acacias and other (non-Acacia) shrubs than Scarlet Robin breeding territories (n = 10) and plots lacking Yellow Robins (n = 7). Yellow Robins nested mostly in gully and lower-slope positions, with a southerly aspect, >40 m from the woodland edge, whereas Scarlet Robins nested mostly on upper slopes and ridges, with no preferred minimum distance from the woodland edge. Most Yellow Robin nests (86% of 58) had overhead foliage within 1 m, shielding them from above, whereas over half (58% of 54) of Scarlet Robin nests were in unconcealed positions. Yellow Robin nests had significantly greater density of cover, and the surrounding habitat was more complex, than for Scarlet Robin nests, in 0.13-ha plots centred on the nest. Breeding success and fledgling survival in the Yellow Robin were positively related to the density of acacias, non-Acacia shrubs and rough-barked saplings (but not gum saplings) in breeding territories. Fledging success and juvenile survival in the Yellow Robin were also positively related to habitat complexity around nest-sites (but not distance to nearest cover, or items of cover within 20 m). Scarlet Robins had exposed nests and suffered high nest predation, with too few successful nests for comparison with unsuccessful nests. Habitat conservation for the Yellow Robin should address the complexity of the ground, shrub and sapling layer in woodland remnants; that for the Scarlet Robin may need to address foraging substrate and ecologically based control of nest predators.


2006 ◽  
Vol 27 (1) ◽  
pp. 19-24
Author(s):  
Tamás Pócs ◽  
Heinar Streimann

During a joint field trip organised by H. Streimann in 1999, the authors collected large amount of bryophytes in Queensland, New South Wales, and Victoria states and in the Austral Capital Territory (A.C.T.). Some of them proved to be new state records, or new records for Australia. The list below is the first selection of these records in Hepaticae, with 16 species newly reported from the whole continent.


Sign in / Sign up

Export Citation Format

Share Document