Relationships Between Grass, Shrub and Tree Cover on Four Landforms of Semi-Arid Eastern Australia, and Prospects for Change by Burning.

1996 ◽  
Vol 18 (1) ◽  
pp. 104 ◽  
Author(s):  
RL Daly ◽  
KC Hodgkinson

The range of grass, shrub and tree levels present in the Louth region of western New South Wales was determined in an area where woody weeds are considered to be rampant, and the prospects for change by burning were evaluated. Relationships between the three vegetation elements in each of four major landforms were determined by regression and reduction in the canopy cover of woody vegetation after one or two fires were simulated. Basal cover of grass was negatively related to canopy cover of woody vegetation, except in the Sandplains and Dunefields landform. The relationship here was curvilinear with maximum grass cover occurring at 10% canopy cover of the woody vegetation. Pastoralism was considered to become less efficient when the canopy cover of woody vegetation exceeded 5%; 44% of sites measured were below this threshold. The remaining sites could be divided into two groups; one which would fall below the threshold if burnt with a prescribed fire (21%) and the other which required two fires or an equivalent second treatment to reduce the cover below the threshold (35%). The survey confirmed the perception of pastoralists, administrators and scientists that shrub cover is unacceptably high for pastoralism throughout much of the region. Additionally the perennial grass cover was very low and this would increase the instability of forage supply to pastoral herbivores. The high spatial variability in the composition of vegetation indicates that graziers need to identify and treat areas where return on investment in rehabilitation will be highest and most certain.

2012 ◽  
Vol 63 (4) ◽  
pp. 389 ◽  
Author(s):  
R. Thapa ◽  
D. R. Kemp ◽  
M. L. Mitchell

Recruitment of new perennial grass plants within existing grassland ecosystems is determined by seed availability, suitable microsites, nutrients and climatic conditions, water and temperatures. This paper reports on the development of criteria to predict recruitment events using modelled soil moisture conditions associated with recruitment of species in five field experiments at Orange (Phalaris aquatica), Trunkey Creek (Austrodanthonia spp.), and Wellington (Bothriochloa macra) in central New South Wales, Australia, and the frequency of those conditions during the past 30 years. Recruitment events were recorded when a rainfall event (median 68 mm across the three sites) kept the surface volumetric soil moisture (0–50 mm) above the permanent wilting point for at least 15 continuous days, allowing for, at most, two ‘dry days’ in between. A key finding from our study is that rainfall events creating favourable soil moisture conditions for seedling emergence typically occurred in the second half of February, sometimes extending to early March. Previously it was thought that recruitment would more likely occur through autumn, winter, and spring when rainfall in southern Australia is more reliable. The 30 years’ data (1975–2004) showed that the P. aquatica site had a median of 20 continuous moist days each year in February–March, whereas, there were 16 and 10 days for the Austrodanthonia and B. macra sites, respectively. The probabilities of exceeding seven or 15 continuous days of moist surface soil were 98% and 78% at the P. aquatica site, 91% and 49% at the Austrodanthonia site, and 73% and 30% at the B. macra site, and indicated that some recruitment is possible in most years. These analyses were extended to several sites across New South Wales, Victoria, and Tasmania to estimate the frequency with which recruitment could occur within natural swards. Across these sites, the probabilities of exceeding seven continuous days of soil moisture were >55% and of exceeding 15 continuous days were lower, which showed that suitable climatic conditions exist during late summer–early autumn across south-eastern Australia for a recruitment event to occur. Future research may show that the criteria developed in this paper could have wider regional application.


2005 ◽  
Vol 33 (1) ◽  
pp. 203-218
Author(s):  
Kerry Heckenberg

THOMASMITCHELL(1792–1855), explorer and Surveyor-General in New South Wales between 1828 and 1855, was a talented and competent draughtsman who was responsible for the original sketches and even some of the lithographs he used to illustrate his two journals of exploration, published in 1838 and 1848. In this paper, I will be concerned with the 1838 journal, entitledThree Expeditions into the Interior of Eastern Australia; with descriptions of the recently explored region of Australia Felix, and of the Present Colony of New South Wales. On the whole, it is a detailed and lavishly illustrated account of the land Mitchell encountered, along with its inhabitants and natural history. My particular interest is in offering an explanation for differences between a sepia sketch depicting a cave at Wellington, NSW, that Mitchell prepared as one of the illustrations for geological material included in this journal, and the final lithograph.


1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.


1985 ◽  
Vol 24 (1) ◽  
pp. 103-114 ◽  
Author(s):  
J. W. Pickett ◽  
C. H. Thompson ◽  
R. A. Kelley ◽  
D. Roman

Thirty-nine species of scleractinian corals have been recovered from under a high dune on the western (mainland) side of North Stradbroke Island, eastern Australia. The corals are associated with thin intertidal sediments and their good condition implies burial in situ and preservation in a saturated zone. Most likely this occurred as the coast prograded and a large dune advanced into the littoral zone, burying intertidal sediments and coral. The species assemblage indicates a sheltered environment but one open to the ocean without wide fluctuations in salinity. Three species yielded a mean 230Th/234U age of 105,000 yr B.P. which is significantly younger than the nearest Pleistocene corals at Evans Head, New South Wales. The corals provide evidence of a sea stand near present sea level during isotope Stage 5c, which is considerably higher than previously suggested for this period. Their good condition implies that the overlying parabolic dune is of comparable age and formed during that high stand of sea level. Also, the isotope age provides a maximum period for the development of giant podzols in the podzol chronosequences on coastal dunes in southern Queensland.


1986 ◽  
Vol 13 (2) ◽  
pp. 213 ◽  
Author(s):  
LW Braithwaite ◽  
M Maher ◽  
SV Briggs ◽  
BS Parker

Populations of waterfowl of three game species, the Pacific black duck Anus superciliosa, grey teal A. gibberifrons, and maned duck Chenonetta jubata, were assessed by aerial survey in October 1983 within a survey region of 2 697 000 km2 of eastern Australia. The numbers of each species were assessed on all surface waters of over 1 ha, and on a sample of smaller surface waters within 10 survey bands each 30 km wide and spaced at intervals of 2� latitude from 20�30' to 38�30'S. The area within the survey bands was 324 120 km2, which gave a sampling intensity of 12.0% of the land surface area. The area of features shown as wetlands or water impoundments within the survey bands on 1 : 2 500 000 topographic maps was 19 200 km2 or 11.2% of the total area of these features in the survey region. The area of surface waters surveyed was assessed at 465 300 ha. Assessments of populations of each species were tallied for wetlands by grid cells of 6 min of 1� longitude along the survey bands (258-309 km2 depending on latitude). Distributions were then mapped, with log*10 indices of populations in each cell. Distributions of the black duck and grey teal showed a pattern of intense aggregation in limited numbers of cells, that of the maned duck was more evenly distributed. The major concentrations of the Pacific black duck were recorded in northern New South Wales and the south-eastern, western, central eastern and central coastal regions of Queensland; those of the grey teal were in south-western, western and northern New South Wales and central-eastern Queensland; the maned duck was broadly distributed over inland New South Wales with the exception of the far west, inland southern Queensland, and central northern Victoria.


2002 ◽  
Vol 54 (2) ◽  
pp. 215-248 ◽  
Author(s):  
F. L. Sutherland ◽  
I. T. Graham ◽  
R. E. Pogson ◽  
D. Schwarz ◽  
G. B. Webb ◽  
...  

2017 ◽  
Vol 68 (2) ◽  
pp. 207 ◽  
Author(s):  
V. Raoult ◽  
V. Peddemors ◽  
J. E. Williamson

Two species of angel shark (Squatina australis, S. albipunctata) and two species of sawshark (Pristiophorus nudipinnis, P. cirratus) are frequently caught in south-eastern Australia. Little is known of the biology of these elasmobranchs, despite being caught as secondary target species in large numbers. The present study collected morphometric and reproductive data from sharks caught in shark-control nets, commercial fishing trawlers and research trawlers in south-eastern Australia. All four species had female-biased sexual size dimorphism, but growth curves between sexes did not differ. Male S. australis individuals were fully mature at ~800-mm total length, male P. nudipinnis at ~900mm, and male P. cirratus at ~800mm. Anterior pectoral margins could be used to determine total length in all species. No morphometric measurement could reliably separate Squatina spp. or Pristiophorus spp., although S. albipunctata over 1000-mm total length had larger eyes than did S. australis.


1998 ◽  
Vol 38 (6) ◽  
pp. 567 ◽  
Author(s):  
G. C. Anderson ◽  
R. D. B. Lefroy ◽  
G. J. Blair

Summary. A glasshouse experiment was conducted to study the correlation between various soil sulfur (S) extractants and pasture response to applied S grown under controlled environmental conditions (glasshouse) as influenced by variations in levels of extractable S. Intact paired soil cores were collected at 2-month intervals from an S x P factorial experiment at 4 field sites on the Northern Tablelands of New South Wales on 11 occasions. Soil samples were collected from each core and the cores placed in the glasshouse. Sulfur was applied to one core of each pair and basal nutrients applied to all cores which were then oversown with white clover (Trifolium repens L. cv. Haifa). The extractable S in the soil was analysed using the following techniques: 0.1 mol Ca(H2PO4)2/L (MCPt); 0.1 mol Ca(H2PO4)2/L, treated with activated charcoal (MCPi); water (H2O); 0.25 mol KCl/L, heated at 40°C for 3 h (KCl-40); 0.25 mol KCl/L, heated at 100°C for 4 h (KCl-100); 0.5 mol NaHCO3/L (NaHCO3); and an acid digestion of the soil (total). Dry matter yield and S content of the pasture shoots were measured for each 2-month growth period. The relationship between the various soil S extraction techniques and the response of pasture to applied S varied over time and was influenced by the level of inorganic S present in the soil and the amount of organic S extracted. When the level of MCPi-extractable S ranged between 2 and 22 µg S/g soil due to the application of fertiliser (summer 1987–88 and autumn 1988), or after a period of high mineralisation rates (spring 1988), the MCPi, MCPt, H2O and KCl-40 techniques had the highest correlation with the increase in S content of the pasture when S was applied. The higher correlation for the MCPt, H2O and KCl-40 techniques than the MCPi technique indicates that plants obtained some S from the organic S pool. In contrast, when the levels of MCPi-extractable S ranged between 2 and 10 µg S/g soil and the rate of mineralisation increased in response to an increase in soil temperature (June 1988 and June 1989) or moisture (September 1989) upon transfer of samples from the field to the glasshouse, the MCPt, H2O and KCl-40 techniques underestimated the available S pool and had lower r2 values than either the KCl-100 or NaHCO3 techniques.


Nematology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 627-653
Author(s):  
Kerrie A. Davies ◽  
Faerlie Bartholomaeus ◽  
Dong Mei Li ◽  
Zeng Qi Zhao ◽  
Weimin Ye ◽  
...  

Summary Ficophagus from collecting trips in eastern Australia, made over 15 years, are summarised and show that species of the genus occurred widely in sycones of Ficus, subgenus Urostigma, section Malvanthera. Two new species (based on morphological differences and molecular sequencing) are described: Ficophagus elizabethae sp. n. from Ficus macrophylla, F. rubiginosa and F. obliqua, and Ficophagus richardi sp. n. from Ficus obliqua; and a morphospecies, Ficophagus Morphospecies malandicus from Ficus obliqua. Ficophagus elizabethae sp. n. is characterised by having the excretory pore (EP) opening from the level of the junction of the conus and shaft of the stylet to that of the knobs, a relatively long procorpus (1.0-2.5 times length of stylet), female tail with an obliquely truncate tail with a hyaline area and a finely to broadly rounded tip which may be mucronate; post-vulval uterine sac (PUS) ca one vulval body diam. (VBD) in length; rose-thorn-shaped spicule with distinct rostrum and prominent condylus; and genital papillae arranged as largest pair adcloacal, second pair posterior to mid-tail length, and third small pair near tail tip; and was collected from Sydney in New South Wales, to Bundaberg in Queensland (QLD). Ficophagus richardi sp. n. is characterised by having the EP opening at the level of the junction of the stylet shaft and conus, a labial cap which is raised around the opening for the stylet; procorpus 0.8-1.7 times length of the stylet, PUS <1 VBD in length, long uterus, and female tail with a V-shaped hyaline area at the bluntly rounded tip; rose-thorn-shaped spicule with a small rostrum and prominent condylus, three pairs genital papillae, first and largest on anterior cloacal lip, second at 70% of tail length measured from cloacal aperture, and third near tip, and was collected from Ban Ban Springs in the south to the Bundaberg region in the mid-north of QLD. In addition, in the absence of pertinent molecular sequences, a morphospecies is described. Ficophagus Morphospecies malandicus is characterised by having the EP opening anterior to the junction of the stylet conus and shaft, procorpus 0.9-2 times length of stylet, a short PUS usually <1 VBD long, short uterus, rose-thorn-shaped spicule with a raised condylus and prominent rostrum, and three pairs of subventral papillae on the tail (one adcloacal, one posterior to mid-tail and one near tail tip); and was collected from the Atherton Tableland, QLD. A table comparing morphological characteristics is provided to help with identification of Ficophagus nematodes from figs of the section Malvanthera in eastern Australia.


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