Importance of mineral nitrogen in the subsoil to yield and uptake of nitrogen by wheat in southern New South Wales

1988 ◽  
Vol 28 (2) ◽  
pp. 215
Author(s):  
AC Taylor ◽  
WJ Lill ◽  
AA McNeill

Dry matter and nitrogen uptake of wheat tops at flowering, dry matter and nitrogen of wheat grain at maturity, and soil mineral nitrogen (0-90 cm) at sowing and flowering, were measured at 68 sites (1 experiment per site in 5 Shires) in southern New South Wales to test the hypotheses that: (i) mineral nitrogen below 30 cm would improve the prediction of wheat yields, (ii) soil mineral nitrogen would be better indicated by wheat yields at flowering than those at maturity, and (iii) soil mineral nitrogen would be better indicated by nitrogen uptake by wheat than by dry matter yields. Mineral nitrogen concentrations in soil at depths greater than 30 cm did not improve the prediction of wheat attributes, but hypotheses (ii) and (iii) were validated. Curvilinear regressions, significant (P< 0.05) on 2 occasions, were not important in this study. The best regression of wheat dry matter at flowering against soil mineral nitrogen at sowing was a single straight line, but the best models for the other 3 wheat variables were all bilinear. The best of the latter related the uptake of nitrogen by wheat at flowering to mineral nitrogen in the soil at sowing as follows: FNUH = (31.6 � 5.9) + (0.892 � 0.110) TMNS30 and FNUL = (9.7 � 7.3) + (0.892 � 0.110) TMNS30 where FNUH is nitrogen uptake by wheat at flowering (kg/ha) in 1960, 1964 and 1966 (when Shire wheat yields were above the Shire's long term average), FNUL is nitrogen uptake by wheat at flowering (kg/ha) in 1961, 1965 and 1974 (when Shire wheat yields were below the Shire's long term average), and TMNS30 is total mineral nitrogen (0-30 cm) (kg/ha) at sowing.


1962 ◽  
Vol 2 (6) ◽  
pp. 185 ◽  
Author(s):  
RR Storrier

In a red-brown earth soil from Wagga Wagga the fluctuations in the level of mineral nitrogen (ammonia plus nitrate-nitrogen) and its availability to wheat under growing period rainfalls of 6 inches and 16 inches were studied. Ammonia-nitrogen did not exceed 8 lb nitrogen per acre 6 inches but showed statistically significant short term fluctuations. Mineral nitrogen decreased steadily from the 4-5 leaf stage of plant growth, reaching minimum values in the ear-emergence period when a temporary nitrogen deficiency occurred. Following rainfalls of about one inch or more, conditions favoured biological activity and nitrogen was mineralized, absorbed by the crop and/or leached down the profile. In one season a release of mineral nitrogen about two weeks before flowering contributed an estimated 20-30 per cent of the total nitrogen uptake of the crop. Nitrogen uptake by the wheat crop ceased after flowering and subsequent changes in mineral nitrogen level reflect the net result of mineralization and demineralization processes, and nitrogen uptake by weeds, particularly skeleton weed. Absorption of nitrogen from the profile depended upon seasonal conditions, with the surface 18 inches suppling the greater part of the nitrogen absorbed by the crop. This indicates the need to sample regularly to at least a depth of 18 inches, particularly during the period from 4-5 leaf to flowering, when studying the relation between mineral nitrogen and crop growth. The data suggest that the response of wheat, as measured by grain yield and protein content, to the higher levels of mineral nitrogen in the improved soils of southern New South Wales is determined by soil moisture levels, particularly in the post-flowering period.



1973 ◽  
Vol 13 (63) ◽  
pp. 423 ◽  
Author(s):  
JW McGarity ◽  
RJK Myers

Fluctuations of mineral nitrogen were studied for three years in two solodized solonetz soils at Narrabri, New South Wales, under a wheat summer-fallow management system. Changes in mineral nitrogen were related to plant uptake, soil environment characteristics (water, temperature and oxygen), and climate. NO3-N was the major form of soil mineral nitrogen, generally exceeding NH4-N with NO2-N occurring only occasionally (<1 �g N g-1). NO3-N accumulated during fallow to 67-111 kg N ha-1 in the profile just after sowing. Crop growth depleted NO3-N to 0-11 kg N ha-1 at flowering. Several significant falls in soil NO3-N (11-27 kg N ha-1) could not be accounted for by plant uptake, and were apparently caused by denitrification. Decreases due to leaching (including lateral leaching) were not detected. Redistribution of NO3-N down the profile was observed, the efficiency of leaching increasing with increased intensity of rainfall. NH4-N generally amounted to less than 25 kg N ha-1. Fluctuations in NH4-N which occurred within the profile, could not be related to observed factors and are unexplained. The effect of a drought year, 1965, was to inhibit mineral nitrogen accumulation, lessen the depth of leaching of NO3-N and depress plant uptake of nitrogen.



1965 ◽  
Vol 5 (18) ◽  
pp. 317 ◽  
Author(s):  
RR Storrier

Ammonium sulphate was added at rates up to 150 lb nitrogen an acre to a soil containing 149 lb mineral nitrogen per acre-18 Inches at sowing, and the seasonal distribution of mineral nitrogen in the soil, nitrogen uptake, and yield of wheat was measured in a better than average season. Some of the applied fertilizer, at all rates of application, was taken up by the crop and resulted in increased dry matter yield and plant nitrogen content at jointing. However, at harvest, total dry matter and grain yield were depressed at all levels of fertilizer application. Grain yield was depressed from 40.5 to 30.5 bushels an acre with the addition of 150 lb nitrogen an acre.Yield potential, as represented by tiller production and spikelets per ear, was increased by fertilizer application, but ear number, grains per ear, and weight per grain, were depressed. Grain number per ear was the principle component of yield under the experimental conditions. Moisture stress and competition for light were responsible for an increase in tiller mortality, which resulted in the depression in ear number with increasing nitrogen supply. Inter-tiller competition for available moisture during the pre-anthesis period caused a decrease in grain number per ear, from 19.3 in the control to 16.6 at the maximum fertilizer rate. It is suggested that inter-tiller competition for available moisture during the pre-anthesis period is an important factor in determining potential grain yield in wheat grown on high fertility soils in southern New South Wales.



2000 ◽  
Vol 22 (1) ◽  
pp. 44 ◽  
Author(s):  
SJ Holdaway ◽  
PC Fanning ◽  
DC Witter

Recent erosion in arid regions of western NSW has exposed large areas that are scattered with stone artefacts manufactured by Aboriginal people in prehistory. These exposures offer an opportunity for archaeologists to study the artefacts abandoned by Aboriginal people through time and to compare those artefacts that accumulate in different parts of the landscape. To reconstruct the nature of prehistoric behaviour in the rangelands, two approaches are needed. First, the geomorphological context of the artefacts needs to be considered since exposure of the artefacts is a function of landscape history. Second, large areas (measured in thousands of square metres) and large numbers of artefacts need to be considered if patterns reflecting long-term abandonment behaviour by Aboriginal people are to be identified. This paper reports on the Western New South Wales Archaeological Program (WNSWAP) which was initiated in 1995 to study surface archaeology in the rangelands. Geomorphological studies are combined with artefact analysis using geographic information system software to investigate Aboriginal stone artefact scatters and associated features such as heat retainer hearths, in a landscape context. Results suggest that apparently random scatters of stone artefacts are in fact patterned in ways which inform on prehistoric Aboriginal settlement of the rangelands. Key words: Aboriginal stone artefacts; rangelands; landscape archaeology; geomorphology; GIs



2021 ◽  
Author(s):  
Christopher Dowling ◽  
Anthony Morgan

The criminal mobility of outlaw motorcycle gang (OMCG) members presents a significant challenge to Australian governments and police. Examining patterns of mobility can help to better understand the opportunity structures that underpin offending by OMCGs and to drive national collaborative responses to these gangs. This study examines the prevalence and patterns of criminal mobility in a sample of almost 4,000 OMCG members in more than 400 chapters. Around one in 10 members showed evidence of criminal mobility over the long term, while more than one-third of chapters comprised criminally mobile members. Criminally mobile gang members were heavily concentrated in a small number of chapters. Patterns of criminal mobility primarily involve movements into east coast jurisdictions. New South Wales and Queensland emerged as the most common destinations for criminally mobile OMCG members.



Author(s):  
Craig Tibbitts

This chapter highlights the long-term influence of Scottish military traditions and identity in Australia, dating back to the arrival of a battalion of the 73rd Highland Regiment in New South Wales in 1810. From the 1860s, several home-grown ‘Scottish’ volunteer militia units were established in the Australian colonies. This coincided with a peak period of Scottish emigration to Australia with some 265,000 settling between 1850 and 1914. With the outbreak of the First World War, Australia quickly raised a contingent to assist the Empire. Several Scottish-Australian militia regiments sought incorporation into the Australian Imperial Force (AIF) but with limited success. This chapter highlights how the existence of Scottish military identities conflicted with the desire of the AIF that its identity be entirely Australian as means of forging the identity of the new Commonwealth of Australia. At the same time, a small number of AIF units managed to maintain some small degree of Scottish flavour about them. Those such as the 4th, 5th and 56th Battalions which had many join en- masse from the pre-war ‘Scottish’ militia regiments, provide examples of how this identity survived and was influenced by some key officers and NCOs of Scots heritage.



2003 ◽  
Vol 43 (1) ◽  
pp. 71 ◽  
Author(s):  
M. K. Conyers ◽  
C. L. Mullen ◽  
B. J. Scott ◽  
G. J. Poile ◽  
B. D. Braysher

The cost of buying, carting and spreading limestone, relative to the value of broadacre crops, makes investment in liming a questionable proposition for many farmers. The longer the beneficial effects of limestone persist, however, the more the investment in liming becomes economically favourable. We re-established previous lime trials with the aim of measuring the long-term effects of limestone on surface acidity (pH run-down), subsurface acidity (lime movement) and grain yield. The study made use of experiments where there was adequate early data on soil chemical properties and cereal yields. We report data from 6 trials located at 4 sites between Dubbo and Albury in New South Wales. The rate of surface soil (0–10 cm) pH decline after liming was proportional to the pH attained 1 year after liming. That is, the higher the pH achieved, the more rapid the rate of subsequent pH decline. Since yields (product removal) and nitrification (also acid producing) may both vary with pH, the post-liming pH acts as a surrogate for the productivity and acid-generating rate of the soil–plant system. The apparent lime loss rate of the surface soils ranged from the equivalent of nearly 500 kg limestone/ha.year at pH approaching 7, to almost zero at pH approaching 4. At commercial application rates of 2–2.5 t/ha, the movement of alkali below the layer of application was restricted. However, significant calcium (Ca) movement sometimes occurred to below 20 cm depth. At rates of limestone application exceeding the typical commercial rate of 2.5 t/ha, or at surface pH greater than about 5.5, alkali and Ca movement into acidic subsurface soil was clearly observed. It is therefore technically feasible to ameliorate subsurface soil acidity by applying heavy rates of limestone to the soil surface. However, the cost and risks of this option should be weighed against the use of acid-tolerant cultivars in combination with more moderate limestone rates worked into the surface soil.There was a positive residual benefit of limestone on cereal grain yield (either barley, wheat, triticale, or oats) at all sites in both the 1992 and 1993 seasons. While acid-tolerant cultivars were less lime responsive than acid-sensitive ones, the best yields were generally obtained using a combination of liming and acid-tolerant cultivars.The long-term residual benefits of limestone were shown to extend for beyond 8–12 years and indicate that liming should be profitable in the long term.



1975 ◽  
Vol 15 (77) ◽  
pp. 795 ◽  
Author(s):  
JA Thompson

A range of temperate annual and perennial legumes, naturalized or commonly sown in the area, was examined at three field sites in low fertility soils derived from granite on the south western slopes of the New England Region, New South Wales. They were compared over a four year period in terms of their persistence, dry matter and nitrogen production and their compatibility with associated temperate perennial grasses, The response of sown grass to nitrogen fertilizer application was also examined in the absence of legume. Ten legumes were examined at one site and six of these at the other two sites. In general, nitrogen yields were ranked similarly to total dry matter yields of all treatments, including grasses in the absence of legume. However, the legumes were ranked differently in terms of productivity of the legume component and productivity of associated grass. At all sites lucerne gave the highest yields of total dry matter and of legume and the lowest yield and persistence of associated grass-comparable to grass growing in the absence of legume or applied nitrogen. Subterranean clover was ranked second or third in total dry matter yield, depending on site, but provided the highest yield of associated grasscomparable to grass receiving high levels of applied nitrogen. Under this legume soil nitrogen levels tended to be highest. Rose clover, sown at one site only, yielded more legume dry matter than subterranean clover but grass yield was comparable to that with lucerne. The results suggest that subterranean clover is the superior legume for successful mixed sowings although inclusion of white clover could be justified. Lucerne appears to be best sown as a pure sward.



1971 ◽  
Vol 11 (50) ◽  
pp. 307 ◽  
Author(s):  
GJ Murtagh

The effectiveness of chemical seedbed preparation for sod-sown oats was studied using varying intervals between spraying and sowing. Four herbicides were compared in a second experiment. Both experiments were conducted on paspalum (Paspalum dilatatum) dominant pastures on red basaltic soil on the North Coast of New South Wales. Herbicides were most effective when applied at 6.7 kg acid equivalent a hectare. At this rate, the highest yields of dry matter and nitrogen were obtained when there was a three-week interval and considerably less when there was no interval. A mixture of 2,2-DPA (2,2-dichloropropionic acid) and amitrole (3-amino-1,2,4-triazole) was more effective than 2,2-DPA alone with a three-week spraying interval but there was no difference with a six-week interval. Both amitrole and a mixture of amitrole and ammonium thiocyanate were ineffective for chemical seedbed preparation on paspalum pastures;



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