Changes in nitrogen and organic carbon of wheat growing soils after various periods of grazed lucerne, extended fallowing and continuous wheat

Soil Research ◽  
1981 ◽  
Vol 19 (3) ◽  
pp. 239 ◽  
Author(s):  
ICR Holford
Keyword(s):  
Organic Carbon ◽  
Soil Nitrogen ◽  
New South ◽  
Mineral Nitrogen ◽  
Soil Types ◽  
First Year ◽  
Fixed Nitrogen ◽  
Total Soil ◽  
South Wales ◽  
Total Soil Nitrogen

Changes in total and mineral nitrogen and organic carbon were measured over a nine year period in two contrasting soils of northern New South Wales after various durations of grazed lucerne, extended fallowing and continuous wheat growing. At least 2 1/2 years of lucerne ley were required to raise the total soil nitrogen above the original level on both soil types. For each year of lucerne growth the average increase (above the control treatments) in total soil nitrogen (0-15 cm) was equivalent to about 140 kg nitrogen ha-1 in the black earth and about 110 kg nitrogen ha-1 in the red-brown earth. Significantly higher levels of soil nitrogen were maintained after the lucerne treatments throughout the 9 years of measurement on the black earth and for 5 years on the red-brown earth. Lucerne had a much larger effect on nitrogen than on organic carbon, which was significantly increased only in the black earth. There were very large increases in mineral nitrogen (0-15 cm) in the first year of measurement after lucerne. Levels remained greater than they were originally for the first 4 years, and they were greater for 7 years in the black earth and 4 years in the red-brown earth following lucerne than following continuous wheat or extended fallow. The decline in mineral nitrogen during wheat cropping after lucerne was greatly increased by excessive rainfall (574 mm or more) during the fallow. Leaching was greater in the red-brown earth than in the black earth, and this explained occasional differences in nitrogen uptake by wheat between the two soil types. Some evidence suggested that under moderately moist conditions nitrogen mineralization from lucerne-fixed nitrogen was greater in the red-brown earth than in the black earth but under drier conditions it was less.

Effects of pasture improvement with superphosphate on soil pH, nitrogen and carbon in a summer rainfall environment

1991 ◽  
Vol 31 (2) ◽  
pp. 221 ◽  
Author(s):  
GJ Crocker ◽  
ICR Holford
Keyword(s):  
Organic Carbon ◽  
Predominantly White ◽  
Soil Ph ◽  
Soil Nitrogen ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Buffering Capacity ◽  
Fixed Nitrogen ◽  
South Wales

The effects of pasture improvement on soil pH, total nitrogen, organic carbon and extractable phosphorus (P) were determined by analysing adjacent soils from improved and unimproved pastures at 67 sites on the Northern Tablelands of New South Wales. Pasture improved sites contained at least 1 clover species, predominantly white clover, and had received at least 125 kg P/ha over periods of 15-45 years. The majority of pasture improved sites contained more soil nitrogen, carbon and phosphorus and were of lower soil pH than adjacent unimproved sites. However, the decreases in pH were not statistically significant and not usually related to the magnitude of the increases in other soil fertility parameters nor to the amounts of superphosphate applied or duration of fertiliser history. The largest decline in soil pH and largest increase in organic carbon were on granitic soils which had received more than 250 kg P/ha. The relatively small decreases in soil pH and lack of relationship with fertiliser history, compared with soils from southern New South Wales, were attributed to: (i) re-cycling of legume-fixed nitrogen by summer-growing grasses; (ii) the naturally lower pH, higher nitrogen content and higher buffering capacity of many northern soils. Soil acidification therefore seems to be much slower and less frequent in the perennial pasture systems of the Northern Tablelands of New South Wales.

The effects of some grazed tropical grass-legume mixtures and nitrogen fertilized grass on total soil nitrogen, organic carbon, and subsequent yields of Sorghum vulgaris

1967 ◽  
Vol 7 (24) ◽  
pp. 66 ◽  
Author(s):  
RJ Jones
Keyword(s):  
Organic Carbon ◽  
Soil Nitrogen ◽  
Crop Yields ◽  
Low Fertility ◽  
Apparent Lack ◽  
Carbon And Nitrogen ◽  
Total Soil ◽  
Significant Difference ◽  
Nitrogen Treatments ◽  
Total Soil Nitrogen

Mixtures of some tropical legumes and Paspalum plicatulum (Michx) cv. Hartley, and stands of P. plicatulum were fertilized with urea at 100 and 200 lb nitrogen an acre a year, and were intermittently grazed by cattle over a period of four years. Soil analyses for organic carbon and for total soil nitrogen in the fourth year of the pasture phase revealed large treatment effects in three of the five replicates. These three replicates which were on a podsolic soil were lower in fertility than the remaining two on a latosolic soil. Soil nitrogen at the 0-3 inch depth in the high nitrogen treatment, and in two Phaseolus atropurpureus D.C. treatments was significantly higher than the control (P<0.05). Organic carbon at the 0-3 inch depth was significantly higher than the control (P<0.05) in the nitrogen treatments and in one of the P. atropurpureus treatments. For both soil nitrogen and organic carbon the Lotononis bainesii Bak. treatment did not differ from the control. There was no significant difference between treatments for soil nitrogen or organic carbon at the 3-6 inch depth though trends were similar to those at 0-3 inches. Organic carbon and nitrogen were closely correlated for all treatments at both depths, and there were no significant differences in the C : N ratio in any treatment. Yields of sorghum grown as a test crop after the pastures were significantly correlated with soil nitrogen values in the three low fertility replicates. A high correlation (r = +0.976) also existed between yields of nitrogen obtained in the pasture phase and test crop yields of nitrogen for all treatments except L. bainesii. Reasons for the apparent lack of improvement in soil nitrogen and carbon on the higher fertility replicates and for the poor test crop yields following L. bainesii are discussed.

Correction - Soil nitrogen status and pasture productivity after clearing of brigalow (Acacia harpophylla)

1981 ◽  
Vol 21 (108) ◽  
pp. 109
Author(s):  
TWG Graham ◽  
AA Webb ◽  
SA Waring
Keyword(s):  
Organic Carbon ◽  
Soil Nitrogen ◽  
Nitrogen Status ◽  
Total Soil ◽  
Total Soil Nitrogen ◽  
Pasture Productivity

At 31 sites of solodized solonetz and solodic soil in central Queensland, the total soil nitrogen (N) and organic carbon (OC) levels of pasture and crop areas were compared with matched uncleared areas of A. harpophylla-Dawson gum (Eucalyptus cambageana)

Soil nitrogen status and pasture productivity after clearing of brigalow (Acacia harpophylla)

1981 ◽  
Vol 21 (108) ◽  
pp. 109
Author(s):  
TWG Graham ◽  
AA Webb ◽  
SA Waring
Keyword(s):  
Organic Carbon ◽  
Soil Nitrogen ◽  
Nitrogen Status ◽  
Total Soil ◽  
Total Soil Nitrogen ◽  
Pasture Productivity

At 31 sites of solodized solonetz and solodic soil in central Queensland, the total soil nitrogen (N) and organic carbon (OC) levels of pasture and crop areas were compared with matched uncleared areas of A. harpophylla-Dawson gum (Eucalyptus cambageana)

Variations in soil organic carbon for two soil types and six land uses in the Murray Catchment, New South Wales, Australia

Soil Research ◽  
2013 ◽  
Vol 51 (8) ◽  
pp. 631 ◽  
Author(s):  
M. C. Davy ◽  
T. B. Koen
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
New South ◽  
New South Wales ◽  
Agricultural Landscapes ◽  
Soil Types ◽  
Land Uses ◽  
South Wales ◽  
Physico Chemical ◽  
Soc Stocks

The aim of this study was to investigate variations in soil organic carbon (SOC) for two soil types and six common land uses in the New South Wales Murray Catchment and to explore the factors influencing those variations. Samples were collected from 100 sites on duplex soils (Ustalfs) of the Slopes region, and 100 sites on red-brown earths (Xeralfs) of the Plains region. Stocks of SOC (0–30 cm) across the study area ranged between 22.3 and 86.0 t ha–1, with means (± s.e.) of 42.0 ± 1.3 and 37.9 ± 0.8 t ha–1 for the Slopes and Plains regions, respectively. Higher SOC stocks were present in pasture-dominated land uses compared with mixed cropping in the Slopes region, with particularly high stocks found in pastures at positions on a slope of 7–10%. No significant differences in SOC stocks were identified between land-use groups (pastures or cropping) in the Plains region (<500-mm rainfall zone). Significant correlations were found between SOC and a range of climatic, topographical, and soil physico-chemical variables at both the catchment and sub-regional scale. Soil physico-chemical and topographical factors play an important role in explaining SOC variation and should be incorporated into models that aim to predict SOC sequestration across agricultural landscapes.

Excess soil nitrogen and the yield and uptake of nitrogen by wheat in southern New South Wales

1965 ◽  
Vol 5 (18) ◽  
pp. 317 ◽  
Author(s):  
RR Storrier
Keyword(s):  
Grain Yield ◽  
Soil Nitrogen ◽  
Dry Matter ◽  
New South ◽  
New South Wales ◽  
Fertilizer Application ◽  
Mineral Nitrogen ◽  
Grain Number ◽  
South Wales ◽  
Ear Number

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.

Effect of Prescribed Burning of Forest Litter on Total Soil Nitrogen

1962 ◽  
Vol 26 (2) ◽  
pp. 200-202 ◽  
Author(s):  
J. O. Klemmedson ◽  
A. M. Schultz ◽  
H. Jenny ◽  
H. H. Biswell
Keyword(s):  
Soil Nitrogen ◽  
Prescribed Burning ◽  
Forest Litter ◽  
Total Soil ◽  
Total Soil Nitrogen

What Trainee Teachers and Teachers Should Know About Aboriginal Children.

1979 ◽  
Vol 7 (5) ◽  
pp. 29-32
Author(s):  
Keyword(s):  
New South ◽  
New South Wales ◽  
Aboriginal Education ◽  
First Year ◽  
First Year Teachers ◽  
Trainee Teachers ◽  
Aboriginal Students ◽  
South Wales ◽  
Aboriginal Children ◽  
Consultative Group

The New South Wales Aboriginal Education Consultative Group feels that more emphasis needs to be placed on the training of teachers in regards to Aboriginal education.Many first year teachers are sent to country areas with a relatively high percentage of Aboriginal students. In the main, these teachers have had little or no contact with Aboriginal children or parents.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby
Keyword(s):  
Small Mammals ◽  
New South ◽  
New South Wales ◽  
Canopy Cover ◽  
Ground Cover ◽  
First Year ◽  
Severe Effect ◽  
South Wales ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

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.

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