Subplasticity in Australian soils. IV. Plasticity and structure related to clay cementation

Soil Research ◽  
1976 ◽  
Vol 14 (3) ◽  
pp. 261 ◽  
Author(s):  
AV Blackmore
Keyword(s):  
New South ◽  
Pore Space ◽  
Clay Content ◽  
Clay Particles ◽  
Highly Active ◽  
South Wales ◽  
Degree Of Orientation ◽  
The Individual ◽  
High Degree ◽  
Stability Of Structure

Subplastic behaviour apparently arises from some form of cementation between clay particles and between groups of particles. Five red-brown earth subsoils from the Riverina area of New South Wales, with subplasticity ratings from SP0 to SPIII+, have been examined here in order to relate plasticity, and other physical properties which reflect structure and stability of structure, to an appropriate laboratory measure, or index, of cementation. The soils were so chosen as to minimize the number of other properties that vary among them. The properties and indexing of the soils in the laboratory show broad consistence with their range of subplasticity as described in the field. When it has been released from cementation, the clay in the more subplastic soils is highly active, having properties similar to those of a montmorillonite with calcium and sodium on the exchange surface. The structure and the high total clay content of the subplastics require a high degree of orientation of individual clay particles into packets or domains. These packets are stabilized by cementation, largely at their edges, and at the same time attached to neighbouring non-parallel packets. Water readily reaches most of the pore space and the material, although very stable, continues to display some properties which are consistent only with a large content of clay particles. Consequently it seems likely that much of the planar surface of the individual clay particle is not contaminated with a cement.

The individual and health sector costs of asthma: the first year of a longitudinal study in New South Wales

2005 ◽  
Vol 29 (5) ◽  
pp. 429-435 ◽  
Author(s):  
Patricia Kenny ◽  
Emily Lancsar ◽  
Jane Hall ◽  
Madeleine King ◽  
Meredyth Chaplin
Keyword(s):  
Longitudinal Study ◽  
New South ◽  
New South Wales ◽  
Health Sector ◽  
First Year ◽  
South Wales ◽  
The Individual

Use of products of straw decomposition by N2-fixing (C2H2-reducing) populations of bacteria in three soils from wheat-growing areas

1986 ◽  
Vol 37 (1) ◽  
pp. 1 ◽  
Author(s):  
MM Roper ◽  
DM Halsall
Keyword(s):  
Nitrogenase Activity ◽  
New South ◽  
Carbon Sources ◽  
Clay Content ◽  
Free Living ◽  
Straw Decomposition ◽  
South Wales ◽  
History Of ◽  
Straw Incorporation ◽  
The Difference

The potential for N2 fixation by free-living bacteria using straw as a source of energy was evaluated in three soils (one from Gunnedah and two from Cowra) representative of the wheat belt in New South Wales. All three soils had a history of straw incorporation. The abilities of the respective microbial populations to use a range of carbon sources, including potential products of decomposition of straw, was determined and compared with the size and composition of each population. Neutral to alkaline (pH 7.4) soil of high (51%) clay content from Gunnedah produced higher rates of nitrogenase activity with straw than more acid (pH 5.6) lower (17%) clay containing soil from Cowra (site B). Gunnedah soil also contained a larger population of N2-fixing bacteria which used a broader range of energy sources than soil from either Cowra site B or Cowra site W (pH 5.8, clay content 34%). There was little difference in the composition of the N2-fixing populations in each of the soils except that Azotobacter spp. were absent from the acid Cowra soils. It was concluded that the difference in behaviour of the respective N2-fixing populations was primarily due to the physical characteristics of the soil affecting the numbers and activities of diazotrophic microorganisms. In addition some soil environments failed to support specific organisms.

Ptyctimous mites (Acari: Acariformes: Oribatida) as zooindicators of changes in Dorrigo National Park in Australia (North Coast Bioregion)

2021 ◽  
Author(s):  
Wojciech Niedbała ◽  
Agnieszka Napierała ◽  
Szymon Konwerski ◽  
Michał Zacharyasiewicz ◽  
Jerzy Błoszyk
Keyword(s):  
Comparative Analysis ◽  
Geographical Distribution ◽  
National Park ◽  
New South ◽  
North Coast ◽  
Local Populations ◽  
South Wales ◽  
Plateau Area ◽  
The Individual ◽  
Research Period

The authors of the study present an analysis of the structure and changes in the examined community of ptyctimous mites (Acari: Acariformes: Oribatida) found in Dorrigo National Park in Australia. The research was conducted during two periods: between 1990 and 1993 and later in 2007. The analysed mite community comprises 35 species, though, the dominance and frequency of particular species were different for each period. In the first research period (1990–1993) in the area of Dorrigo National Park, 28 species were recorded, whereas in 2007 – 23 species were found. There were 16 species that occurred in both research periods, and 12 species only in the samples collected in the 90’s, and 7 species only in those collected in 2007. The analysis also embraces the geographical distribution of the species in the area of Australia. Three species were designated as endemic, occurring only in the area of the examined national park (Austrophthiracarus dissonus Niedbała et Collof, 1997, Austrophthiracarus parapulchellus Niedbała, 2006 and Notophthiracarus distinctus Niedbała, 1989). The analysed samples contained only few specimens of these species. Due to the low abundance, great rarity of the local populations and high endemism, these species should be regarded as potentially endangered (EN according to the IUCN scale). A comparative analysis of the community from Dorrigo National Park (New South Wales) with those found in other larger areas of Australia in Victoria (Otway Ranges Area, Yarra Ranges Area, Strzelecki Ranges Area and Errinundra Plateau Area) examined by Niedbała and Szywilewska-Szczykutowicz (2017) has revealed that the communities found in Dorrigo National Park contained far more species, which constituted 30% of the whole fauna of Australia. In contrast to the communities of ptyctimous mites from Dorrigo, the individual communities in the area of Victoria contained only between 5% and 14% of all known species in Australia from this group.

Collective orientation by nocturnally migrating Australian plague locusts, Chortoicetes terminifera (Walker) (Orthoptera: Acrididae): a radar study

1983 ◽  
Vol 73 (4) ◽  
pp. 679-692 ◽  
Author(s):  
V. A. Drake
Keyword(s):  
Quantitative Analysis ◽  
New South ◽  
Analysis Procedure ◽  
Observation Site ◽  
Collective Orientation ◽  
South Wales ◽  
Variable Quantity ◽  
Degree Of Orientation ◽  
Radar Measurements ◽  
Position Indicator

AbstractThe collective orientation of Chortoicetes terminifera (Wlk.) migrating at night in New South Wales was studied with a radar. Measurements of the distribution of insect echoes on the radar's plan-position-indicator display provide information about the variation of both the direction and the degree of orientation with both height and time. A quantitative analysis procedure used in a detailed study of one particularly interesting series of observations is described. It was found that collective orientation occurred frequently, and that it sometimes became very well-developed. The direction of orientation remained approximately constant for long periods, but did not appear to be consistently related to any obvious directional cue; changes in direction were observed on occasions, however, and one such change was clearly associated with a change in the direction of the wind. The degree of collective orientation was a rather more variable quantity than the direction, and increases in degree were sometimes associated with increases in the number of locusts arriving at the observation site.

Studies on structure in plant communities. V. Pattern in Atriplex vesicaria communities in South-Eastern Australia

1967 ◽  
Vol 15 (3) ◽  
pp. 451 ◽  
Author(s):  
DJ Anderson
Keyword(s):  
Plant Communities ◽  
New South ◽  
Stocking Density ◽  
South Australia ◽  
Effective Rainfall ◽  
South Wales ◽  
Eastern Australia ◽  
Apparent Decrease ◽  
Original Vegetation ◽  
The Individual

The distribution pattern of Atriplex vesicaria (perennial saltbush) was examined in a number of locations extending from Hay in western New South Wales to Koonamore Station in South Australia. The populations sampled were from a range of locations exhibiting a variety of topographical, edaphic, and effective rainfall conditions. The scales and intensities of pattern varied considerably between sites, but in all sites there was evidence of contagion on at least two scales (both larger than could be attributed to the morphology of the individual plants) and in no instance was there evidence of uniform (underdispersed) distribution. The two major scales of pattern were attributable to the development of gregariousness and either the patchiness of nodulated limestone (or gypsum) in the soils or the development of gilgai relief. It was demonstrated for one site that drought stress had brought about an apparent decrease in the stocking density of A. vesicaria; this reduction of density was associated with a decline in pattern intensity, although the scales of pattern present in the original vegetation were maintained in the residual population.

Evaluation of tree establishment treatments on saline seeps near Wellington and Young in New South Wales

2000 ◽  
Vol 40 (1) ◽  
pp. 99 ◽  
Author(s):  
N. E. Marcar ◽  
A. K. M. A. Hossain ◽  
D. F. Crawford ◽  
A. T. Nicholson
Keyword(s):  
New South ◽  
New South Wales ◽  
Eucalyptus Camaldulensis ◽  
Stem Diameter ◽  
Tree Establishment ◽  
South Wales ◽  
Crown Volume ◽  
Casuarina Cunninghamiana ◽  
Atriplex Nummularia ◽  
The Individual

The success of tree establishment on both saline and non-saline sites is dependent on the use of appropriate pre- and post-planting procedures. The 4 trials reported here on 2 dryland saline sites, near Wellington and Young in New South Wales, deal with the individual and combined effects of mulch, fertiliser, tree guards and pre-conditioning with salt and waterlogging, alone and in combination, on survival and growth of Acacia stenophylla, Atriplex nummularia, Casuarina cunninghamiana, Eucalyptus camaldulensis and Melaleuca halmaturorum. Each trial included 1 or more of these species. Soil salinity was assessed at the plot level using a hand-held electromagnetic induction device (EM38). Treatments had variable effects, depending on species, site, experiment and treatment combinations. Mulch application significantly improved height in 2 trials and, in combination with plastic guard and fertiliser, produced the best results. Treatments generally increased basal stem diameter or stem diameter at breast height, and crown volume, but the differences were usually not statistically significant. The combined effect of mulch, fertiliser and plastic guard on growth was usually greater than any single treatment.

Surface structure in gray clays of northwestern New South Wales in relation to micromorphology, cation suite and particle size attributes

Soil Research ◽  
1992 ◽  
Vol 30 (1) ◽  
pp. 1 ◽  
Author(s):  
IP Little ◽  
AJ Ringrose-Voase ◽  
WT Ward
Keyword(s):  
Particle Size ◽  
Surface Structure ◽  
New South ◽  
Clay Mineralogy ◽  
Clay Content ◽  
Structural Behaviour ◽  
South Wales ◽  
Field Assessment ◽  
Structured Soils ◽  
Textural Attributes

Considerable differences in surface structure (0-100 mm) were observed in the field in two adjacent areas of grey clays near Narrabri, N.S.W. The absence of any differences in clay mineralogy and granulometry of the sand fraction supported the field assessment that both types of soil were similar in provenance. A transect of soil profiles including seven with poor structure and five with well-structured surface horizons was examined. The field observations of structure were supported by photographs of the surface, and water entry after rain. Micromorphological examination showed that closely spaced porphyric to adporphyric fabric in the poorly structured soils contributed to poor structure, highlighting the importance of textural attributes. The well-structured soils had a more widely spaced porphyric fabric. A measure of dispersibility depending on clay content and exchangeable plus soluble Na, Ca and Mg tallied very well with the field assessment of soil structure. Five groups were obtained from a euclidean distance/flexible sort strategy on the basis of cation suite, carbon content and particle size attributes. The groups identified areas of poor structure very well and the groups appear to be discriminated mainly on the basis of differences in Na, Ca and clay content. Treating the transect as a continuum of soils of very poor structure at site 1 grading to very good at site 12 showed that greater values for Ca, K, and clay were associated with good structure and greater values for Mg, C and silt were associated with poor structure. The sodium adsorption ratio and ionic strength of the soil solution were not on their own good predictors of structural behaviour possibly due to the independent contribution of Ca and Mg in this respect.

scholarly journals 'Remember Aesi':

2021 ◽  
Vol 28 ◽  
pp. 46-71
Author(s):  
Kiera Lindsey
Keyword(s):  
New South ◽  
Large Male ◽  
Colonial History ◽  
Art Gallery ◽  
Familiar Figure ◽  
South Wales ◽  
Outer Domain ◽  
Indigenous Uses ◽  
Definition Of ◽  
The Individual

In this article I draw upon a definition of ‘dialogical memorial’ offered by Brad West to offer an experimental artist's brief that outlines the various ways that a contemporary monument to the colonial artist, Adelaide Eliza Scott Ironside (1831-1867), could ‘talk back’ to the nineteenth-century statues of her contemporaries, and ‘converse’ with more recent acts of history making. In contrast to the familiar figure of the individual hero, which we associate with the statuary of her age, I suggest a group monument that acknowledges the intimate intergenerational female network which shaped Aesi's life and also ‘re-presents’ – a term coined by the historian Greg Dening – several native born and convict women from the Georgian, Regency and Victorian eras who influenced her life. Instead of elevating Aesi upon a plinth, I recommend grounding this group monument on Gadigal country and planting around it many of the Australian Wildflowers she painted in ways that draw attention to the millennia-old Indigenous uses of the same plants. And finally, by situating Aesi’s monument in the Outer Domain (behind the New South Wales Art Gallery in Sydney’s Botanic Gardens and to the east of the Yurong Pennisula, near Woolloomooloo Bay), in an area where she once boldly assumed centre stage before a large male audience in a flamboyant moment of her own theatrical history-making, I argue that this memorial will have the capcity to speak for itself in ways that challenge the underepresentation of colonial women in Sydney's statuary, abd, as West suggests, do much to ‘alter the stage on which Sydney's colonial history 'is narrated and performed’.   [i] Greg Dening, Performances, Melbourne University Press, Melbourne, 1992, p37.

The economics of temperate pasture systems on the central and southern Tablelands of New South Wales

2001 ◽  
Vol 23 (2) ◽  
pp. 159 ◽  
Author(s):  
D. T. Vere ◽  
R. E. Jones ◽  
M. H. Campbell
Keyword(s):  
Native Species ◽  
Programming Model ◽  
New South ◽  
Perennial Grass ◽  
New South Wales ◽  
Perennial Grasses ◽  
Economic Returns ◽  
High Quality ◽  
South Wales ◽  
The Individual

Pastures are the basis of most forms of agricultural production on the New South Wales central and southern tablelands. Pastures occupy the bulk of the region's landmass and pasture-based livestock production annually contributes more than three-quarters of the regional gross value of rural production. Throughout the region, there is substantial variation in pasture composition, ranging from high quality introduced perennial grasses and legumes to pastures comprising mainly low quality native species. This paper examines the economics of the main categories of temperate pastures over a range of soil fertility-rainfall environments on the south-eastern tablelands areas of New South Wales. Using a linear programming model and discounted development budgets, the results demonstrate the strong influence of the environment on the economics of the individual pasture systems. The highest economic returns in both the short and longer-terms were to the introduced perennial grass pastures in most of the environments. Pastures based on introduced legumes and the high quality native species also generated sound economic returns, although there are recognised problems with the persistence of the legume pastures. Over time, the returns to the better quality native pastures compare favourably with the introduced legumes and are better suited to acidic soils than the perennial grasses. Low quality native species produced relatively poor economic returns in all environments and unfortunately, are the main pasture type in the region's less favourable environments.

The Olivines of a Differentiated Teschenite Sill Near Gunnedah, New South Wales

1956 ◽  
Vol 93 (6) ◽  
pp. 441-455 ◽  
Author(s):  
J. F. G. Wilkinson
Keyword(s):  
Optical Properties ◽  
New South ◽  
New South Wales ◽  
Olivine Composition ◽  
South Wales ◽  
The Individual

AbstractData is presented on textural variation, optical properties, and resultant compositions of the olivines from a differentiated teschenite sill. The range in olivine composition is from Fa21 to Fa,60. Both the individual crystals and successive crops of crystals become more fayalitic with progressive differentiation.

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