The Relationship Between Bulk Electrical Conductivity and Dryland Salinity in the Narrabri Formation at Breeza, Liverpool Plains, New South Wales, Australia

1997 ◽  
Vol 5 (3) ◽  
pp. 109-123 ◽  
Author(s):  
R. Ian Acworth ◽  
Jerzy Jankowski
Keyword(s):  
Electrical Conductivity ◽  
New South ◽  
New South Wales ◽  
Dryland Salinity ◽  
South Wales ◽  
Bulk Electrical Conductivity ◽  
The Relationship

Salt source for dryland salinity - evidence from an upland catchment on the Southern Tablelands of New South Wales

Soil Research ◽  
2001 ◽  
Vol 39 (1) ◽  
pp. 39 ◽  
Author(s):  
R. I. Acworth ◽  
J. Jankowski
Keyword(s):  
New South ◽  
New South Wales ◽  
Dust Storms ◽  
Dryland Salinity ◽  
Heterogeneous Distribution ◽  
Small Catchment ◽  
South Wales ◽  
Bedrock Weathering ◽  
Salt Distribution ◽  
The Last Glacial

A detailed study involving drilling, geophysics, hydrogeochemistry, and groundwater monitoring over a 10-year period has been carried out at a small catchment south-east of Yass on the Southern Tablelands of New South Wales to investigate the source of salt causing dryland salinity. The catchment is within 2 km of the top of a regional groundwater and surface water divide and remains substantially tree covered. The investigations have found a highly heterogeneous distribution of salt, most of which is associated with swelling clay. Dispersion of this clay causes the surface features commonly associated with dryland salinity. There is no hydrogeochemical evidence to suggest evaporative or transpirative concentration of salt in the groundwater. The short flow path from the top of the catchment cannot provide a significant source of salt from bedrock weathering. An alternative model of salt accumulation is proposed with the salt imported into the catchment with silt during dust storms in the arid and windy conditions during the last glacial. The management implications of this model of salt distribution and the associated dryland salinity development are discussed.

Fire studies in Mallee (Eucalyptus spp.) communities of western New South Wales: spatial and temporal fluxes in soil chemistry and soil biology following prescribed fire

1995 ◽  
Vol 2 (4) ◽  
pp. 398 ◽  
Author(s):  
J. C. Noble ◽  
D. J. Tongway ◽  
M. M. Roper ◽  
W. G. Whitford
Keyword(s):  
Electrical Conductivity ◽  
Soil Chemistry ◽  
Nitrogenase Activity ◽  
New South ◽  
New South Wales ◽  
Bare Soil ◽  
Soil Samples ◽  
Soil Biology ◽  
South Wales ◽  
Micro Organisms

The effects of prescribed fires on nutrient pools, soil micro-organisms, and vegetation patch dynamics were studied in three semi-arid mallee shrublands in western New South Wales. Repeated sampling of surface soil strata (0–2 and 2–4 cm) was undertaken at strategic times (immediately before and after the fire, after opening autumn rain, mid-season in the winter, and at the end of the spring) in five microsites (inner, middle and outer mallee litter zones, bare soil, and Triodia hummock). These samples were later analysed for pH, electrical conductivity, organic carbon and available nitrogen. The effect of fire on soil micro-organisms in these microsites was also examined by measuring nitrogenase activity and enumerating soil Acari. Carbon and nitrogen levels were consistently higher in the inner mallee microsites whereas bare soil sites provided the lowest values. Significant microsite x soil depth interactions were recorded in two shrubland sites while highly significant (P < 0.001) depth x sampling time interactions were recorded in three sites. The most sensitive soil parameter with respect to microsite was electrical conductivity, particularly in the surface 0–2 cm stratum. Highest values were again recorded from the inner mallee microsites and the lowest from bare soil sites. Nitrogenase activity was highest in soil samples associated with mallee litter and, where litter was removed by fire, activity decreased markedly except in the bare soil samples where activity was higher in the burnt samples. Soil microarthropod populations also declined notably following fire. Mites from the Prostigmata greatly outnumbered those from other suborders, a total of 12 families (15 genera) being enumerated in control sites compared with three families (three genera) only of Cryptostigmata. Nonetheless the most abundant mites were cryptostigmatids (Aphelacarus spp.) found in unburnt hummocks beneath Triodia plants. The ecological and management implications of these spatial and temporal fluxes in soil chemistry and soil biology are discussed in relation to their effects on landscape processes, particularly water and nutrient redistribution.

Bunch covers, leaf number and yield of bananas

1970 ◽  
Vol 10 (47) ◽  
pp. 802 ◽  
Author(s):  
DW Turner
Keyword(s):  
Water Relations ◽  
New South ◽  
New South Wales ◽  
Leaf Length ◽  
Leaf Number ◽  
South Wales ◽  
North Eastern ◽  
Number Of Leaves ◽  
The Relationship

The effects of plastic bunch covers and varying defoliation treatments on bunch weight were measured on Williams bananas at Alstonville in north-eastern New South Wales. Bunch covers did not significantly affect bunch weight. The number of leaves left on the plant at bunch emergence only reduced yield when less than four leaves were present. Leaf length duration was calculated and was positively related to bunch weight. Bunch covers did not alter the relationship between leaf number and yield. The rate of sucker growth and water relations within the plants were altered by defoliation treatments. Both of these effects were greatest when less than three leaves were left on the plant.

scholarly journals Screen-time, obesity, ageing and disability: findings from 91 266 participants in the 45 and Up Study

2010 ◽  
Vol 14 (1) ◽  
pp. 34-43 ◽  
Author(s):  
Emily Banks ◽  
Louisa Jorm ◽  
Kris Rogers ◽  
Mark Clements ◽  
Adrian Bauman
Keyword(s):  
Physical Activity ◽  
Screen Time ◽  
Vegetable Consumption ◽  
New South ◽  
New South Wales ◽  
Full Time ◽  
Obesity Prevalence ◽  
Cross Sectional ◽  
South Wales ◽  
The Relationship

AbstractObjectiveTo assess the relationship between obesity and sedentary behaviours, such as watching television or using a computer (‘screen-time’), and describe how this relationship varies between population subgroups.DesignCross-sectional analysis of the relationship between obesity (BMI ≥ 30 kg/m2) and screen-time, adjusted for age, sex, income and education and compared according to a range of personal characteristics.SettingNew South Wales, Australia.SubjectsA total of 91 266 men and women aged 45 years and above from the general population of New South Wales in 2006–2007 and providing self-reported information on height and weight and other factors.ResultsObesity prevalence was 21·4 %. Compared to individuals with <2 h of daily screen-time, the adjusted relative risks (RR) of obesity were 1·35 (95 % CI 1·26, 1·44), 1·70 (95 % CI 1·59, 1·82), 1·94 (95 % CI 1·81, 2·08) and 1·92 (95 % CI 1·80, 2·06) for 2–3, 4–5, 6–7 and ≥8 h, respectively. The increase in obesity with increasing screen-time was similar within categories of overall physical activity, but was attenuated in those in full-time paid work, compared to non-workers (P for interaction < 0·0001). Among non-workers, the overall obesity RR per 2 h increase in daily screen-time was 1·23 (95 % CI 1·21, 1·25) and was significantly elevated in all groups examined, ranging from 1·16 to 1·31 according to sex, level of age, education, income, smoking and fruit consumption. The RR did not differ significantly according to overall physical activity, region of residence and alcohol and vegetable consumption, but was substantially lower in disabled v. not-disabled individuals (P for interaction < 0·0001).ConclusionsObesity increases with increasing screen-time, independent of purposeful physical activity. This was observed in all population groups examined, although it is attenuated in full-time workers and disabled individuals.

Low nodulation and nitrogen fixation of mungbean reduce biomass and grain yields

2005 ◽  
Vol 45 (3) ◽  
pp. 269 ◽  
Author(s):  
D. F. Herridge ◽  
M. J. Robertson ◽  
B. Cocks ◽  
M. B. Peoples ◽  
J. F. Holland ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Grain Yield ◽  
New South ◽  
New South Wales ◽  
Soil Nitrate ◽  
Grain Yields ◽  
South Wales ◽  
Negative Effect ◽  
On Farm ◽  
The Relationship

Apparent nodulation failures and associated low grain yields have been reported for commercial mungbean (Vigna radiata) crops in southern Queensland and northern New South Wales. We therefore conducted on-farm surveys of 40 commercial mungbean crops in the region in which symbiotic traits, i.e. nodulation and nitrogen fixation, and biomass and grain yield were monitored. Effects of bradyrhizobial inoculation and inoculation methods on mungbean and soybean (Glycine max) symbiosis and yield were determined in experiments at 3 sites in northern New South Wales. Thirty-four of the 35 mungbean crops assessed for nodulation were nodulated. The relationship between soil nitrate to a depth of 90 cm at sowing and mungbean nodulation was not significant. However, at low-to-moderate soil nitrate levels (<100 kg N/ha), the mean nodule score was 1.6, compared with 0.5 at high (>100 kg N/ha) soil nitrate levels. Soil nitrate had a negative effect on the percentage of mungbean nitrogen derived from nitrogen fixation (%Ndfa). Mean %Ndfa values for soil nitrate levels <50, >50–100 and >100 kg N/ha were 35, 22 and 19% respectively. Grain yields of the surveyed mungbean crops varied from 0.3 to 2.1 t/ha, and were correlated with shoot dry matter. Grain yield was not significantly correlated either with sowing soil nitrate, nodule score or %Ndfa. In the inoculation experiments, mungbean did not nodulate as well as soybean, producing about one-third the number of nodules. Both species responded to inoculation with increased nodulation, although data from one of the sites suggested that responses during early growth of mungbean were not maintained during pod-fill. Effects of inoculation on mungbean %Ndfa were marginal. Average increases were 9%, based on natural 15N abundance, and 6%, based on the ureide method. Soybean %Ndfa, on the other hand, responded strongly to inoculation, with increases of 56 (15N) and 77% (ureide). Inoculation increased mungbean crop N by an average of 10% and grain yield by 6%, compared with responses to fertiliser nitrogen of 31% (crop N) and 10% (grain yield). For soybean, inoculation increased crop nitrogen by 43% and grain yield by 7%, similar to responses to fertiliser nitrogen of 45 (crop N) and 5% (grain yield). These results suggest that inoculated mungbean was N-limited and that inoculation of mungbean using current technology may be somewhat ineffectual. We concluded that low nodulation and nitrogen fixation of commercial mungbean most likely results from the suppressive effects of nitrate and/or insufficient numbers of bradyrhizobia in the soil. When low symbiosis and low soil nitrate are combined, N is likely to limit crop growth, and potentially grain yield. Suggested strategies for improving mungbean nodulation and nitrogen fixation in the northern grains belt include selection of more symbiotically competent plant and bradyrhizobial genotypes and more effective utilisation of established soil populations of mungbean bradyrhizobia.

The relationship between vegetation patterns and environment on the south coast of New South Wales

1995 ◽  
Vol 72 (1) ◽  
pp. 71-80 ◽  
Author(s):  
I.A. Neave ◽  
S.M. Davey ◽  
J.J. Russell-Smith ◽  
R.G. Florence
Keyword(s):  
New South ◽  
New South Wales ◽  
South Coast ◽  
Vegetation Patterns ◽  
The South ◽  
South Wales ◽  
The Relationship
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