Field measurements of nitrogenase activity in soils amended with wheat straw

1983 ◽  
Vol 34 (6) ◽  
pp. 725 ◽  
Author(s):  
MM Roper
Keyword(s):  
Nitrogenase Activity ◽  
New South ◽  
Field Measurements ◽  
Field Capacity ◽  
Nitrogen Fertilizers ◽  
Free Living ◽  
Straw Decomposition ◽  
Indirect Measure ◽  
South Wales

Nitrogenase activity and decomposition of straw were examined in situ in two areas (Gunnedah and Cowra) representative of large areas of the New South Wales wheat belt. Measurements of nitrogenase activity were made by adapting the acetylene reduction assay for use in the field. Evolution of CO2 was monitored as an indirect measure of decomposition of straw. The addition of straw to soil stimulated nitrogenase activity which was related to the amount of straw added and the rate of straw decomposition. There were significant levels of activity provided the soil was moist and warm. Nitrogenase activity increased with mean daily soil temperature (up to at least 30�C) and decreased as the soil dried from field capacity. It is concluded that nitrogen fixation by free-living nitrogen-fixing microorganisms in soils amended with straw may contribute to the nitrogen status of the soil and thus reduce the need for nitrogen fertilizers.

Use of products of straw decomposition by N2-fixing (C2H2-reducing) populations of bacteria in three soils from wheat-growing areas

1986 ◽  
Vol 37 (1) ◽  
pp. 1 ◽  
Author(s):  
MM Roper ◽  
DM Halsall
Keyword(s):  
Nitrogenase Activity ◽  
New South ◽  
Carbon Sources ◽  
Clay Content ◽  
Free Living ◽  
Straw Decomposition ◽  
South Wales ◽  
History Of ◽  
Straw Incorporation ◽  
The Difference

The potential for N2 fixation by free-living bacteria using straw as a source of energy was evaluated in three soils (one from Gunnedah and two from Cowra) representative of the wheat belt in New South Wales. All three soils had a history of straw incorporation. The abilities of the respective microbial populations to use a range of carbon sources, including potential products of decomposition of straw, was determined and compared with the size and composition of each population. Neutral to alkaline (pH 7.4) soil of high (51%) clay content from Gunnedah produced higher rates of nitrogenase activity with straw than more acid (pH 5.6) lower (17%) clay containing soil from Cowra (site B). Gunnedah soil also contained a larger population of N2-fixing bacteria which used a broader range of energy sources than soil from either Cowra site B or Cowra site W (pH 5.8, clay content 34%). There was little difference in the composition of the N2-fixing populations in each of the soils except that Azotobacter spp. were absent from the acid Cowra soils. It was concluded that the difference in behaviour of the respective N2-fixing populations was primarily due to the physical characteristics of the soil affecting the numbers and activities of diazotrophic microorganisms. In addition some soil environments failed to support specific organisms.

Evidence of High Sea Level during Isotope Stage 5c in Queensland, Australia

1985 ◽  
Vol 24 (1) ◽  
pp. 103-114 ◽  
Author(s):  
J. W. Pickett ◽  
C. H. Thompson ◽  
R. A. Kelley ◽  
D. Roman
Keyword(s):  
Sea Level ◽  
New South ◽  
Good Condition ◽  
Coastal Dunes ◽  
Intertidal Sediments ◽  
South Wales ◽  
Eastern Australia ◽  
Maximum Period ◽  
High Dune

Thirty-nine species of scleractinian corals have been recovered from under a high dune on the western (mainland) side of North Stradbroke Island, eastern Australia. The corals are associated with thin intertidal sediments and their good condition implies burial in situ and preservation in a saturated zone. Most likely this occurred as the coast prograded and a large dune advanced into the littoral zone, burying intertidal sediments and coral. The species assemblage indicates a sheltered environment but one open to the ocean without wide fluctuations in salinity. Three species yielded a mean 230Th/234U age of 105,000 yr B.P. which is significantly younger than the nearest Pleistocene corals at Evans Head, New South Wales. The corals provide evidence of a sea stand near present sea level during isotope Stage 5c, which is considerably higher than previously suggested for this period. Their good condition implies that the overlying parabolic dune is of comparable age and formed during that high stand of sea level. Also, the isotope age provides a maximum period for the development of giant podzols in the podzol chronosequences on coastal dunes in southern Queensland.

Biodiversity of intertidal marine flatworms (Polycladida, Platyhelminthes) in southeastern Australia

Zootaxa ◽  
2021 ◽  
Vol 5024 (1) ◽  
pp. 1-63
Author(s):  
JORGE RODRÍGUEZ ◽  
PAT A. HUTCHINGS ◽  
JANE E. WILLIAMSON
Keyword(s):  
Dna Sequences ◽  
New South ◽  
Marine Biota ◽  
Free Living ◽  
Marine Fauna ◽  
Southeastern Australia ◽  
Marine Habitats ◽  
South Wales ◽  
Molecular Sequencing ◽  
Insight Into

Flatworms of the Order Polycladida are a group of free-living invertebrates found in a diversity of marine habitats, with over 800 species described worldwide. Marine flatworms are a conspicuous component of Australia’s marine fauna yet have received little attention. Less than 30 scientific articles have been published on Australian marine flatworms since 1855, of which only nine include species from southeastern Australia. Here, the biodiversity and distribution of species belonging to the Order Polycladida inhabiting intertidal rocky beaches in southeastern Australian waters were identified and analysed. Sampling was conducted at low tide along the coasts of New South Wales and Victoria. Collected samples were serially sectioned for comparative anatomical studies, and tissue was removed from each individual for molecular sequencing and analyses. Both nuclear and mitochondrial DNA sequences were obtained and used as an additional source of evidence for the description of new species as well as providing further insight into the phylogenetic relationships between them. A total of 20 species, six of which are new (e.g., Eulatocestus australis sp. nov.), and a new genus (Parabolia gen. nov.) have been described, as well as two new records for Australia (e.g., Stylochoplana clara Kato, 1937) have been identified increasing our knowledge of this important component of the Australian marine biota.  

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.

The significance of intercalary ammonium in representative surface and subsoils from southern New South Wales

Soil Research ◽  
1976 ◽  
Vol 14 (3) ◽  
pp. 381 ◽  
Author(s):  
GJ Osborne
Keyword(s):  
Ammonium Sulphate ◽  
New South ◽  
New South Wales ◽  
The Other ◽  
Nitrogen Fertilizers ◽  
Irrigated Agriculture ◽  
Nitrogen Economy ◽  
Ammonium Fixation ◽  
South Wales

Six surface and subsoils known to contain native intercalary ammonium were examined to assess the importance of ammonium fixation when nitrogen fertilizers were applied, the availability of native and recently fixed intercalary ammonium to plants, and the effect of potassium on fixation. Only one soil, a grey soil of heavy texture (Ug 5.4), fixed significant amounts of added ammonium sulphate, the level of intercalary ammonium being increased by 55 % in the surface and 100% in the subsoil. The native level of intercalary ammonium was reduced by 8 and 17% by the growth of plants in the red-brown earth (Dr 2.23) and the grey soil of heavy texture, respectively, but was unchanged in the other soils. The addition of small amounts of potassium prior to the ammonium did not affect fixation; however, additions of 500 ppm reduced the fixation of a 200 ppm solution of ammonium by 80 %. Intercalary ammonium is not considered to be important in the nitrogen economy of five of the six major farming soils of the slopes and plains area of southern New South Wales. The sixth, the grey soil of heavy texture, is an alluvium associated with the Murrumbidgee River and its tributaries, and as such is used extensively for irrigated agriculture. Because this soil can fix large amounts of ammonium, the use of ammonium or ammonium forming fertilizers is not recommended.

Seasonal Field Energetics of the Rufous Rat-Kangaroo (Aepyprymnus-Rufescens)

1992 ◽  
Vol 40 (3) ◽  
pp. 279 ◽  
Author(s):  
IR Wallis ◽  
B Green
Keyword(s):  
New South ◽  
Water Flux ◽  
Behavioural Ecology ◽  
Free Living ◽  
Doubly Labelled Water ◽  
South Wales ◽  
Poor Understanding ◽  
Males And Females ◽  
The Mean ◽  
The Difference

Water flux and field metabolic rate (FMR) were measured by the doubly labelled water (DLW) method in free-living male and female rufous rat-kangaroos Aepyprymnus rufescens near Drake in northern New South Wales. The mean FMR of 499 kJ kg-1 day-1 was similar in winter and summer even though the difference in mean minimum temperatures between the two seasons was 20-degrees-C. Furthermore, we did not find any differences in FMR between males and females even though several females carried large pouch young or had young-at-foot. A poor understanding of the diet and the behavioural ecology of A. rufescens makes ft difficult to explain the similarities between sexes and seasons.

Morphological observations on the Erthrocytes, Leukocytes and Platelets of Free-Living Platypuses, Ornithorhynchus anatinus (Shaw) (Monotremata : Ornithorhynchidae)

1983 ◽  
Vol 31 (4) ◽  
pp. 421 ◽  
Author(s):  
PJ Canfield ◽  
RJ Whittington
Keyword(s):  
New South ◽  
New South Wales ◽  
Free Living ◽  
Ultrastructural Studies ◽  
South Wales ◽  
Ornithorhynchus Anatinus

Blood was collected from the bill sinus of 10 healthy, mature platypuses captured in the Upper Shoalhaven River of New South Wales. Blood from all 10 animals was used for light microscopic morphometrical studies, and that from four of them was used for ultrastructural studies. The erythrocytes presented no unusual features and were similar to those described for other monotremes, marsupials and man. Platelets were of a mammalian type and uniform. Features of the leukocytes were compared and contrasted with those of other monotremes, marsupials, domestic mammals and man. Unusual features of the leukocytes of the platypus included the consistent presence of Dohle bodies within segmented neutrophils, and the nonsegmented nature of nuclei of eosinophils and basophils. Ultrastructural studies confirmed these findings.

Efficiency of utilization of nitrogen fertilizers on representative soils from southern New South Wales

1976 ◽  
Vol 16 (83) ◽  
pp. 875 ◽  
Author(s):  
GJ Osborne ◽  
RR Storrier
Keyword(s):  
Ammonium Sulphate ◽  
Sodium Nitrate ◽  
New South ◽  
New South Wales ◽  
Phosphorus Uptake ◽  
Nitrogen Fertilizers ◽  
Soil Reaction ◽  
Nitrogen And Phosphorus ◽  
South Wales ◽  
Nitrogen And Phosphorus Uptake

The effects were examined in a glasshouse study of three forms of nitrogen fertilizer (urea, ammonium sulphate and sodium nitrate) on the yield, and nitrogen and phosphorus uptake of ryegrass (Lolium perenne) in six representative farming soils from the southern slopes and plains of New South Wales. The results indicated an average recovery of 82 per cent of applied nitrogen across the three forms of fertilizer and the six soils. Ammonium sulphate led to decreases in soil reaction of the order of 0.8-1.5 pH units and lower recoveries; sodium nitrate increased pH. Ammonium sulphate as a source of nitrogen is considered undesirable as it gave lower dry matter yields and nitrogen recovery values compared with the other fertilizer forms. In addition, because of its effect on soil reaction, it could lead to the loss of nutrients by leaching or fixation processes.

Estimation of evapotranspiration from rice in southern New South Wales: a review

1994 ◽  
Vol 34 (7) ◽  
pp. 1069 ◽  
Author(s):  
E Humphreys ◽  
WS Meyer ◽  
SA Prathapar ◽  
DJ Smith
Keyword(s):  
Water Use ◽  
New South ◽  
Meteorological Data ◽  
Strong Dependence ◽  
New South Wales ◽  
Radiant Energy ◽  
Field Measurements ◽  
High Water ◽  
Management Plan ◽  
South Wales

This paper reviews field measurements of evapotranspiration from rice (ET rice) in the Murrumbidgee Valley of southern New South Wales. The results are compared with US Class A open pan evaporation (E pan) at CSIRO Griffith, and with reference evapotranspiration (ETo) calculated using a locally calibrated Penman equation. Both methods (+ETrice = +Epan or +ETrice = +ETo) give good estimates of total evapotranspiration from flooded rice over the ponded season of about 5 months, from October to February. Variation between seasons in total ETo, rainfall, and ETo minus rainfall is large. Over 32 years, total seasonal ETo varied by a factor of 1.5, while rainfall varied >10-fold. The irrigation water requirement for rice +(ETo - rainfall) varied from 685 mm in 1992-93 to 1350 mm in 1990-91. This large variation highlights the need to adjust the rice water use limit (16 ML/ha or 1600 mm) on a seasonal basis, to detect and eliminate high water use paddocks where percolation to the groundwater or surface runoff is excessive (>2 ML/ha). On average, an irrigation requirement of 10.5 ML/ha is needed to replace net evaporative loss +(ETo - rainfall) for rice flooded for 5 months, October-February. Monthly totals of ETo are compared for several locations within the rice-growing areas of southern New South Wales, and differences between locations are found to be small and not significant. This reflects the strong dependence of evaporation on radiant energy, which is unlikely to vary spatially to a significant extent across the region. ETo calculated from meteorological data collected at CSIRO Griffith therefore provides a definitive basis for estimating evapotranspiration from rice in southern New South Wales. Furthermore, CSIRO Griffith has a computerised meteorological data base going back to the 1930s. Current meteorological data and historical records are readily available by contacting the Metdata Manager. Therefore, the case is made for using CSIRO Griffith ETo as the reference for estimating evapotranspiration from rice in southern New South Wales. This study provides farmers, Land and Water Management Plan groups, and policy makers with a tool that can be used, on a yearly basis, to evaluate rice paddock water use efficiency. It should be adopted to confine rice growing to the least permeable soils.

New SHRIMP U-Pb zircon provenance and in situ monazite metamorphic ages from the Mount Robe Subblock, Broken Hill, New South Wales: July 2015–June 2017

2018 ◽  
Author(s):  
N. Kositcin ◽  
J.A. Fitzherbert ◽  
P.T. Main ◽  
K. Waltenberg
Keyword(s):  
New South ◽  
New South Wales ◽  
Broken Hill ◽  
South Wales
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