A statistical-chemical characterization of four great soil groups in Southern New South Wales based on orthogonal polynomials

Soil Research ◽  
1970 ◽  
Vol 8 (3) ◽  
pp. 221 ◽  
Author(s):  
JD Colwell

Statistical procedures are described for the characterization and comparison of profiles within soil classification units. Profile trends in a measured characteristic are represented by the coefficients of orthogonal polynomials in depth, and these coefficients are used as observations for standard statistical procedures. The mean of the respective coefficients provides estimates of the mean profiles for the classification units, and the variance-covariance matrix of the coefficients can be used to calculate the confidence intervals of these means. Differences between the mean profiles can be tested by analyses of variance. The variability of a range of chemical properties in the profiles of four Great Soil Groups, viz. yellow podzolic, red earth, red-brown earth, and grey clay, is described. The characterization is based on the analysis of profiles sampled from areas of about 0.4 ha chosen to represent cultivated examples of the groups in southern New South Wales. Variability of most soil properties is greater between these areas than within them, notable exceptions being exchangeable calcium and magnesium within the grey clay Group. This high localized variability is attributed to the gilgaied nature of this group in this region. Also variation between the soil groups is generally greater than within the groups. The differences seem, however, of limited importance from the point of view of soil fertility.

1971 ◽  
Vol 11 (52) ◽  
pp. 541
Author(s):  
JD Colwell

Estimates are made of the desirable number of soil core samples that should be taken from the sites of field experiments for the estimation of profile trends in chemical properties for between site comparisons. The estimates are made on the basis of the magnitude of within site variance relative to between site variance. Fewer samples are required when between site variance is high than when it is low. The data were obtained from the sites of experiments representing four great soil groups in southern New South Wales. The desirable number of samples varies amongst the soil groups, with the chemical properties and with depth down the soil profile. Estimates for mean profile trends and for the means of individual depth strata were similar, It is concluded that at least 9 to 12 core samples should be taken per site and preferably 29 to 40 to ensure reasonably safe estimates of profile trends in important chemical properties.


1998 ◽  
Vol 46 (2) ◽  
pp. 153 ◽  
Author(s):  
Damon L. Oliver

The regent honeyea ter, Xanthomyza phrygia, is an endangered woodland bird whose range and population size have decreased in the last thirty years. Suggested reasons for this decline include abnormal breeding behaviour, poor reproductive output, and excessive inter- and intra-specific aggression. This study investigated the breeding behaviour and aggressive interactions of regent honeyeaters during the nest construction, incubation, nestling, and fledgling stages in two consecutive breeding seasons in the Bundarra–Barraba region near Armidale, New South Wales. The female was entirely responsible for nest construction and incubation, which is typical of many honeyeaters. Both parents fed the nestlings, and at a similar rate, although only the female brooded chicks on the nest. Both parents fed the fledglings. The mean frequency at which nestlings (23 times per hour) and fledglings (29 times per hour) were fed is the highest published rate of any non-cooperative honeyeater. Breeding males were involved in significantly more aggressive interactions with conspecifics and other nectarivores than were females, although the overall percentage of day-time spent in aggression for both sexes was low (2.5%). It appears that abnormal breeding behaviour, poor reproductive effort, or excessive aggression are not experienced by this species in northern New South Wales, and that other factors are likely to be responsible for its current low population level.


1994 ◽  
Vol 34 (1) ◽  
pp. 33 ◽  
Author(s):  
GM Lodge

Burrs were collected from paddocks on 3 properties in northern New South Wales where the age of the Trifolium subterraneum var. brachycalycinum cv. Clare swards varied from 19 to 28 years. At 1 site burrs were also sampled from swards sown 2 and 10 years previously. Twenty seedlings from these burrs and 20 plants of certified cv. Clare were grown as spaced plants in a nursery. These were assessed for vegetative and floral characters, flowering time, number of seeds per burr, seed weight, and percentage hardseed after storage at 25/25�C for 6 months and 25/45�C for a further 6 months. For most plants the mean number of days from sowing to first flower was similar to that of Clare. Compared with the naturalised strains, Clare had the lowest (P<0.05) mean number of seeds per burr: about 25% below the mean of the strains (2.7 seeds per burr). While the lowest mean seed weights of the strains were not significantly different from those of Clare, the seed weights of plants from 3 sites were higher (P<0.05) than those of Clare. After storage for either 6 or 12 months, hardseed levels were also lowest (P<0.05) for Clare. Plants from the 2-year-old sward had the same median number of seeds per burr (2.0) as Clare. As sward age increased, the median number of seeds per burr increased to 2.8. Hardseed percentages were lowest for plants of Clare and for those from the 2-year-old sward after 6 months, and for Clare after 12 months. These studies indicated the presence of divergent strains in old swards of Clare in a summer rainfall environment. Natural selection among variability within Clare is the most likely reason for the development of these strains in an environment marginal for the long-term persistence of this softseeded cultivar. Although strains had the same vegetative and floral markings as Clare, differences in ecologically important characters such as number of seeds per burr, seed weight, and hardseededness may result in plants that are better adapted to the environment in which they evolved. From these studies 23 plants of T. subterraneum var. brachycalycinum were selected for further evaluation.


1960 ◽  
Vol 11 (5) ◽  
pp. 705
Author(s):  
WD Andrew ◽  
FW Hely

The frequency of eight annual species of Medicago was determined on 10 soil groups in a region climatically favourable for medics. They occurred on nine of these, the overall frequency being in the order M. minima (L.) Bart. > M. denticulata Willd. > M. laciniata (L.) Mill., M. praecox DC., M. tribuloides Desr., and M. orbicularis (L.) Bart. > M. arabica (L.) Huds. and M. confinis Koch. M. minima was more tolerant of variation of soil habitat than any other medic in the region. M. denticulata was most commonly found on the soils of high soluble salt content and showed the greatest tolerance of poor drainage conditions. M. laciniata occurred in greatest abundance on soils of the well-drained brown acid group. M. praecox was most commonly found on soils with a compact gravelly surface. M. tribuloides was recorded on five soil groups but was common only on the black earths. M. orbicularis was confined to the black earth and red loam soils. M. arabica was rarely found, being restricted to lower, fertile, well-drained parts of the landscape, and M. confinis occurred only occasionally and then in association with M. denticulata.


1967 ◽  
Vol 7 (24) ◽  
pp. 7 ◽  
Author(s):  
P McInnes ◽  
TJ Grainger ◽  
MD Smith

Data are presented on the recovery and reproductive performance of 2 1/2-year-old maiden Merino ewes after a prolonged period of undernutrition. The 217 sheep had been hand-fed on a submaintenance ration in pen feeding trials at Glenfield, New South Wales. During the seven months of the trials they had lost 6 kg (28 to 22 kg) body weight. They were transported to Condobolin in south-western New South Wales, divided into two treatment groups and run on good quality pastures. One group was joined immediately (May 1959) and again ten months later, and the other group was mated after six months at Condobolin (in October 1959) and again 12 months later. The ewes recovered rapidly. The mean weight of both groups had reached 30 kg within six weeks and 40 kg within six months. In the first year 73 of the 100 May-mated ewes bore lambs, but only 38 of these lambs were weaned. Ewes bearing lambs had a higher body weight at the start of joining and gained more during joining than the barren ewes. At the other three joinings (October 1959, May 1960, October 1960) lambing percentage was from 86-89 and weaning percentage from 62-69-both normal for the district. The proportion of twin lambs (3-6 per cent) was low. Wool weight in 1959 was not affected by time of mating or by pregnancy.


1978 ◽  
Vol 1 (2) ◽  
pp. 167
Author(s):  
VR Squires

In order to assess the current level of stock watering facilities on pastoral properties within the western Riverina district of New South Wales and to relate this information to paddock size and vegetation type, large of areas of land (785,000 ha) within the region were surveyed. Paddock boundaries and the location of watering points were plotted. Watering points were classified as to type. Three broad vegetation types were represented: chenopod shrublands (Atriplex and Maireana spp.) degraded grasslands (Stipal Danthonia spp.), and mallee woodlands (Eucalyptus socinlis F. Meull., E, oleosa, F. Meull.) Size of paddocks was related to the dominant vegetation type. On the degraded grasslands in the eastern part of the study area the mean paddock size was 746 ha; on the chenopod shrublands it was 780 ha, and in the Malleedominated areas it was 1,553 ha. The number of permanent watering points per paddock varied from one to four. Less than half the paddocks (43%) had fresh water available as well as saline waters from sub-artesian bores. Almost half the paddocks (47%) were so large, or the watering points so positioned, that the sheep would need to walk more than 3 km to reach the most remote parts of the paddock when temporary waters had dried up. Overall 18% of the land in the non- mallee areas was more than 3 km from permanent water. Therefore the majority of the land could be used in all seasons. Generally the central and northern Riverina district is adequately watered. It would be uneconomic to supply permanent water in the mallee woodlands. In some paddocks in the chenopod dominated area extra watering points may be justified.


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.


1967 ◽  
Vol 15 (6) ◽  
pp. 1163 ◽  
Author(s):  
WH Ewers

A morph-frequency cline and a size cline are described for the snail Velacumantus australis. The frequency of a white-banded form decreases clinally with latitude South. Living populations from Queensland and northern New South Wales have frequencies between 7 and 18% whereas all populations from southern New South Wales and eastern Victoria, except those from Lake Illawarra, have frequencies between 2 and 5%. The frequency in Port Phillip Bay is less than 0.1%. The frequency in a sample from Swan River, Western Australia, was 9.1% about the same as in samples from localities of the same latitude on the eastern coast of Australia. The frequency in most fossil samples was similar to that in nearby living populations. The mean length of populations from the eastern states increases clinally with increase in latitude South, although there are some irregular fluctuations between adjacent populations which are probably influenced by population density.


Soil Research ◽  
2018 ◽  
Vol 56 (8) ◽  
pp. 780 ◽  
Author(s):  
Mark Conyers ◽  
Beverley Orchard ◽  
Susan Orgill ◽  
Albert Oates ◽  
Graeme Poile ◽  
...  

Estimating the likely variance in soil organic carbon (OC) at the scale of farm fields or smaller monitoring areas is necessary for developing sampling protocols that allow temporal change to be detected. Given the relatively low anticipated soil OC sequestration rates (&lt;0.5 Mg/ha.0.30 m/year) for dryland agriculture it is important that sampling strategies are designed to reduce any cumulative errors associated with measuring soil OC. The first purpose of this study was to evaluate the spatial variation in soil OC and nitrogen (N), in soil layers to 1.50 m depth at two monitoring sites (Wagga Wagga and Yerong Creek, 0.5 ha each) in southern New South Wales, Australia, where crop and pasture rotations are practiced. Four variogram models were tested (linear, spherical, Gaussian and exponential); however, no single model dominated across sites or depths for OC or N. At both sites, the range was smallest in surface soil, and on a scale suggesting that sowing rows (stubble) may dominate the pattern of spatial dependence, whereas the longer ranges appeared to be associated with horizon boundaries. The second purpose of the study was to obtain an estimate of the population mean with 1%, 5% and 10% levels of precision using the calculated variance. The number of soil cores required for a 1% precision in estimation of the mean soil OC or N was impractical at most depths (&gt;500 per ha). About 30 soil cores per composite sample to 1.50 m depth, each core being at least 10 m apart, would ensure at least an average of 10% precision in the estimation of the mean soil OC at these two sites, which represent the agriculture of the region.


1980 ◽  
Vol 20 (102) ◽  
pp. 25
Author(s):  
RDH Cohen

Lamb production was studied in an experiment that ran for four years, 1968 to 1972, at Grafton, New South Wales, in a region where no commercial sheep are grown. Merino and Dorset Horn x Merino ewes stocked at 15 ewes ha-1 were mated in spring to Border Leicester rams and the lambs sold for slaughter in October. The mean number of lambs born per 100 ewes mated was 81.7 for crossbred ewes and 48.4 for Merino ewes (P< 0.05) and the mean carcase weights of the lambs were 14.8 kg and 12.7 kg, respectively (P< 0.01). The mean weight of fleeces cut from Merino ewes (3.24 kg) was greater (P< 0.01) than that from crossbred ewes (2.58 kg). The ewes were treated with anthelmintics either every four weeks or according to climatic conditions. There were no significant differences between the anthelmintic treatments for lamb liveweights at birth, weaning or slaughter; carcase weight; ewe fleece weight; or mortality rate. Treatment every four weeks increased ewe live weight during only one short period from August 1971 to February 1972 (P< 0.05). Data from this experiment compared favourably with survey data for the high rainfall zone in Australia and it was concluded that prime lamb production on the north coast of New South Wales is biologically feasible.


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