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.

Acid buffering capacity and potential acidification of cotton soils in northern New South Wales

Soil Research ◽  
2003 ◽  
Vol 41 (5) ◽  
pp. 875 ◽  
Author(s):  
Balwant Singh ◽  
I.O.A. Odeh ◽  
A. B. McBratney
Keyword(s):  
Soil Ph ◽  
New South ◽  
New South Wales ◽  
Agricultural Practices ◽  
Buffering Capacity ◽  
N Fixation ◽  
Potential Threat ◽  
Study Region ◽  
South Wales ◽  
Acid Buffering

Soil acidity has been of major concern in Australia since European settlement. Acidification processes have been accelerated due to agricultural activities such as N fertiliser application and leguminous N-fixation in farm rotations. In this paper, we measured the acid buffering capacity (pHBC) of Vertosols, soils used predominantly for growing cotton in northern New South Wales. The pHBC values were used to calculate decrease in soil pH assuming net acid input due to agricultural practices. We combined the acidification results with geostatistics to spatially simulate the decline in soil pH of surface soils over time. The results indicate that it would take 10–417 years for soil pH to decrease by 1 unit on an assumed acid input of 5�kmol�H+/ha.year. Soil pH will drop by 1 unit within 100 years for 90% of the soils and within 15 years for 10% of the soils. This reflects the variability of the pHBC for the studied soils. In 50 years from present, most of the eastern and north-western parts of the study region may become highly acidic with soil pH declining to 5.5. There may be a potential threat to sustainable agriculture from acidification in the region, although more work needs to be done to corroborate the counter-effects of water fluxes and carbonate dissolution. Sensitivity analysis indicates that even at low levels of acid input, some areas in the study region may experience significant decline in soil pH in the surface layer.

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.

Effect of soil pH on the distribution ofDanthoniaspecies on the tablelands of central and southern New South Wales

1996 ◽  
Vol 39 (4) ◽  
pp. 619-621 ◽  
Author(s):  
P. M. Dowling ◽  
D. L. Garden ◽  
D. A. Eddy ◽  
D. I. Pickering
Keyword(s):  
Soil Ph ◽  
New South ◽  
New South Wales ◽  
South Wales

Driving factors of soil organic carbon fractions over New South Wales, Australia

Geoderma ◽  
2019 ◽  
Vol 353 ◽  
pp. 213-226 ◽  
Author(s):  
Jonathan Gray ◽  
Senani Karunaratne ◽  
Thomas Bishop ◽  
Brian Wilson ◽  
Manoharan Veeragathipillai
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
New South ◽  
New South Wales ◽  
Driving Factors ◽  
Carbon Fractions ◽  
South Wales ◽  
Organic Carbon Fractions ◽  
Soil Organic Carbon Fractions

Characterisation of naturalised strains of Trifolium subterraneum var. brachycalycinum cv. Clare in northern New South Wales

1994 ◽  
Vol 34 (1) ◽  
pp. 33 ◽  
Author(s):  
GM Lodge
Keyword(s):  
Seed Weight ◽  
New South ◽  
New South Wales ◽  
Trifolium Subterraneum ◽  
Summer Rainfall ◽  
Median Number ◽  
South Wales ◽  
The Mean ◽  
Floral Characters ◽  
Number Of Seeds

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.

The effect of biosolids on cereals in central New South Wales, Australia. 1. Crop growth and yield

2005 ◽  
Vol 45 (4) ◽  
pp. 435 ◽  
Author(s):  
J. L. Cooper
Keyword(s):  
Sewage Sludge ◽  
Soil Ph ◽  
New South ◽  
New South Wales ◽  
Acid Soils ◽  
Crop Growth ◽  
Growth And Yield ◽  
South Wales ◽  
Sludge Cake ◽  
Dewatered Sewage Sludge

Two forms of biosolids, with and without lime, were applied to acid soils at 2 sites in central New South Wales. Wheat and triticale were then grown on these sites to determine the effect of biosolids on crop growth and yield. The forms of biosolids used were dewatered sewage sludge cake, and N-Viro Soil which is a lime amended sewage sludge. Dewatered sewage sludge cake was applied at rates of 0, 6, 12 and 24 dry Mg/ha, and N-Viro soil at 0, 1.5, 3.0 and 4.5 dry Mg/ha. Biosolids produced grain yield increases of over 50% at both sites, with the largest yield increases at the highest rate of dewatered sewage sludge. Continued cropping at 1 of the sites showed that significant yield increases were still obtained 3 years after the initial application. The addition of lime and N-Viro Soil raised soil pH, and produced small but long lasting yield increases. However, the main benefit of biosolids seems to have come from the nutrients they supplied rather than changes in soil pH.

Rhizobium as a factor in the re-establishment of legume-based pastures on clay soils of the wheat belt of north-western New South Wales

1998 ◽  
Vol 38 (6) ◽  
pp. 555 ◽  
Author(s):  
A. M. Bowman ◽  
D. M. Hebb ◽  
D. J. Munnich ◽  
J. Brockwell
Keyword(s):  
Nitrogen Fixation ◽  
Rhizobium Meliloti ◽  
New South ◽  
New South Wales ◽  
Clay Soils ◽  
Natural Fertility ◽  
Fixed Nitrogen ◽  
South Wales ◽  
Annual Medics ◽  
North Western

Summary. Populations of Rhizobium meliloti in self-mulching clay soils (Vertisols) at 48 sites on 27 properties in north-western New South Wales were classified according to number and ability to fix nitrogen with several species of Medicago. Rhizobia were counted using serial dilution, nodulation frequency, plant infection tests. Abilities of the soil populations to fix nitrogen were determined in the laboratory with whole-soil inoculation of Medicago seedlings in test tubes with shoots exposed to the atmosphere and roots within the tubes under bacteriological control, and in the field using a technique based on the natural abundance of 15N in the soil. The majority of soils contained >1000 cells of R. meliloti per gram. The major component of those populations fixed nitrogen with lucerne (Medicago sativa) and some components of some soils also fixed nitrogen with M. polymorpha, M. scutellata, M. littoralis, M. tornata, M. laciniata and Trigonella suavissima. However, a number of soils were located which contained few if any rhizobia effective in nitrogen fixation with M. polymorpha. Overall, the effectiveness of nitrogen fixation of the naturally occurring populations of R. meliloti in association with M. polymorpha, M. scutellata, M. littoralis and M. tornata was only 46% of the effectiveness of standard strains. At one particular site, where 10 lines of annual Medicago spp. were growing experimentally, fixed nitrogen as a proportion of shoot nitrogen averaged only 28%. At that site, there were no effective rhizobia for M. scutellata and it was wholly dependent on the soil as the source of its nitrogen. The results are discussed in relation to the need for a substantial input of legume nitrogen for restoring the natural fertility of self-mulching clay soils in degraded wheat lands of north-western New South Wales. It is suggested that lucerne, or perhaps other perennial Medicago spp., might fill this role better than annual medics such as M. polymorpha and M. scutellata that are more dependent than lucerne on specific strains of R. meliloti to meet their requirements for symbiotic nitrogen fixation.

The butterfly fauna of the Griffith district, a fragmented semi-arid landscape in inland southern New South Wales

2006 ◽  
Vol 12 (2) ◽  
pp. 140 ◽  
Author(s):  
Michael F. Braby ◽  
Ted D. Edwards
Keyword(s):  
Species Richness ◽  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Wagga Wagga ◽  
Fragmented Landscape ◽  
South Wales ◽  
Butterfly Fauna ◽  
Semi Arid

Thirty-three species of butterflies are recorded from the Griffith district in the semi-arid zone of inland southern New South Wales. The butterfly community comprises the following structure: 19 species (58%) are resident; 7 (21 %) are regular immigrants; 2 (6%) are irregular immigrants; 5 (15%) are vagrants. Except for a few migratory species, most occur in relatively low abundance. Lack of similar studies elsewhere in western New South Wales precludes generalizations regarding the species richness, composition and structure of semi-arid butterfly communities. Comparison of the butterfly fauna with that from five other inland regions on the slopes and foothills of the Great Diving Range, revealed that the Griffith district is most similar in species richness and composition to that of Deniliquin and to a lesser extent Wagga Wagga and Cowra in the south, than with two regions in the higher summer rainfall area of the north of the State (Coonabarabran-Mendooran, Narrabri-Bellata). Overall, the butterfly fauna of inland New South Wales (total of 73 species, of which 49 occur in the southern regions) is depauperate compared with that recorded from the coastal/subcoastal areas east of the Great Dividing Range. Attention is drawn to the conservation significance of several vegetation types and habitat remnants in the Griffith district. Much of the native vegetation in the district has been extensively modified since European settlement due to excessive clearing for agriculture, resulting in a highly fragmented landscape for the conservation of native flora and fauna. With the exception of the lycaenid Candalides hyacinthinus Simplex, which is considered threatened locally, there is a general absence of narrow range endemic butterflies associated with mallee-heathland or mallee-woodland, possibly as a result of widespread land clearing practices of mallee vegetation in the past.

Vegetation changes after fire on two land systems in arid North-west New South Wales.

1985 ◽  
Vol 7 (2) ◽  
pp. 80 ◽  
Author(s):  
WE Mulham
Keyword(s):  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Summer Rainfall ◽  
Botanical Composition ◽  
Dune System ◽  
Erosion Risk ◽  
North West ◽  
South Wales

Following a sequence of favourable years in which pasture growth over much of the arid zone of Australia reached very high ievels, controlled burns were carried out on two contrasting vegetation types in the extreme north-west of New South Wales. A wheei-point apparatus was used to measure subse- quent changes in botanical composition and foliage cover over a four year period. On a pasture periodically dominated by Mitchell grass (Astrebla spp.) burning while growing conditions were favourable resulted in only a small long- term decrease in the cover of Mitchell grass. In the short-term all chenopod species were eliminated and a wider range and greater abundance of annual forbs were promoted in the following spring. On a similar area burned by wildfire in a year of low summer rainfall the response from Mitchell grass was much poorer and botanical composition of the pasture present in the following spring differed from that which developed in the spring following the controlled burn. It also differed from that of the unburnt pasture. The major differences were due to the response of forb species and are attributed to variation in seasonal rainfall. On a dune-system pasture the dominant grasses were species of Aristida and Enneapogon. These are relatively short-lived and appear to have little ability to regrow from the butt after fire. Their slow regeneration after the burn was reflected in the substantial increase in relative abundance of perennial forbs in the following autumn, and of annual forbs the next spring. Although fire appeared to have no long-term effect on the pasture it dramatically reduced tree and shrub numbers. It is suggested that during years in which abnormal quantities of Mitchell grass are present in this region, controlled burning could be a useful form of management. A mosaic of patches burnt at different times would reduce the potential for wide-scale wildfires, provide refuge areas for stock and wildlife in the event of wildfire, and promote a wider choice of plant material for grazing animals. However, in dune-systems vegetation, removal of the pasture cover and reduction of the tree and shrub density would constitute an erosion risk.

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