Studies on some neutral red duplex soils (Dr 2.12) in north-eastern Queensland. 3. Availability of phosphorus in the C-horizon

1975 ◽  
Vol 15 (76) ◽  
pp. 689
Author(s):  
ME Probert

The C horizon phosphorus in neutral red duplex soils derived from granodiorite is shown by electron microprobe analysis to be present as coarse grains of apatite. Glasshouse experiments failed to show any contribution from this phosphorus to the nutrition of the test crops (Townsville stylo Stylosanthes humilis and green panic Panicum maximum). Since this phosphorus is soluble in 0.01 N H2SO4, this extractant grossly overestimated the available phosphorus status whereas extraction with 0.5 M NaHCO3 indicated the non-availability of the C horizon phosphorus in these soils.


1976 ◽  
Vol 16 (78) ◽  
pp. 94 ◽  
Author(s):  
RJK Myers

Soil changes after 3-15 years of fertilized leguminous pastures on Tindall clay loam soil at Katherine, N.T. were studied by comparison of leguminous pasture soils with their native counterparts. Soil organic carbon, total nitrogen, C/N ratio and pH were unchanged by the presence of Townsville stylo (Stylosanthes humilis). Available phosphorus (bicarbonate extraction) was significantly higher under legume pasture, reflecting its fertilizer history, but there was no pattern of increase with time, nor with quantity of fertilizer. Available nitrogen (boiling water extraction) was higher under legume pasture, and both the absolute value under legume pasture and the change in amount were correlated significantly with the age of the pasture. Available nitrogen after three years of legume pasture was equal to that under unimproved pasture, suggesting that gains in this period merely balanced losses during clearing and establishment.



1971 ◽  
Vol 11 (50) ◽  
pp. 336 ◽  
Author(s):  
BJ Crack

Glasshouse experiments using the subtractive technique were conducted on 15 neutral red duplex soils from north-eastern Queensland. On two of the soils factorial experiments were conducted to obtain information on nutrient interactions. The legumes Phaseolus lathyroides and Stylosanthes humilis were used as test plants. All soils were deficient in phosphorus, sulphur, and molybdenum, although the magnitude of the various deficiencies often differed between soils. Yields of plants were well correlated with phosphorus extracted from the soils by 0.01 N.H,SO, and by 0.5 M. Na HCO3. Soil tests used were unsatisfactory indices of sulphur deficiency. A possible zinc deficiency was indicated.



1971 ◽  
Vol 11 (50) ◽  
pp. 328
Author(s):  
BJ Crack ◽  
RF Isbell

Morphological and chemical data are presented for neutral red duplex soils (Dr2.12) derived from granodiorite and diorite in north-eastern Queensland under a strongly seasonal summer rainfall. Mean annual totals range from about 24 inches (610 mm) to nearly 40 inches (1000 mm). The soils have slightly acid loamy A, horizons which overlie structured red clay B horizons of slightly acid to neutral reaction. C horizons containing much weathered rock occur at 50-70 cm and continue to depths exceeding two metres. Profiles show a consistent trend for many chemical properties ; a particular feature being the relatively high accumulation of phosphorus in the C horizon. Certain chemical analyses of surface soils are sufficiently consistent within and between sites to provide a broad regional characterization of plant nutrient status. The soils of the Charters Towers region have low nitrogen, organic carbon, and available phosphorus contents but potassium levels are moderate. Home Hill-Bowen soils are more variable but indicate generally higher fertility levels.



1972 ◽  
Vol 12 (56) ◽  
pp. 274 ◽  
Author(s):  
BJ Crack

The effect of the legume Townsville stylo (Stylosanthes humilis) on soil nitrogen status was studied under mown plots with different conditions of establishment and fertilizer application on a solodic soil in north- east Queensland. Increase in soil total nitrogen 0-7.5 cm of 180 kg N per ha and total nitrogen accession (plant and soil) of 460 kg N per ha was measured over a four year period where the legume was sown into existing spear grass and fertilized with superphosphate at 375 kg per ha per year. Soil nitrogen increases did not occur until the pasture was legume dominant and main increases took place where superphosphate was applied. Under these conditions there was also a dry season accumulation of soil nitrate nitrogen.



1969 ◽  
Vol 37 (288) ◽  
pp. 447-452 ◽  
Author(s):  
E. A. J. Burke ◽  
C. Kieft ◽  
R. O. Felius ◽  
Maria S. Adusumilli

SummaryStaringite, (Fe,Mn)0·5(Sn,Ti)4·5(Ta,Nb)1·0O12, occurs as inclusions in tapiolite from pegmatites at Seridózinho and Pedra Lavreda, Paraiba State, NE. Brazil. An indexed powder pattern is presented. The mineral is tetragonal with a 4·742 Å and c 9·535 Å, and most probably has a ‘trirutile’ structure. Electron-microprobe analysis yielded Ta2O5 21·5%, Nb2O5 1·8, SnO2 73·3, TiO2 0·03, FeO 3·7, MnO 0·3, sum 100·6%. Dcalc 7·17. Micro-indentation hardness (load 100 g) 1033–1187 kg/mm2; reflectivity at 470 nm (R0) 12·8 to (R′e) 14·5%, at 546 nm 12·1–13·9, at 589 nm 12·0–13·7, and at 650 nm 11·8–13·6; staringite is uniaxial positive.



Author(s):  
R. I. Johnsson-Hegyeli ◽  
A. F. Hegyeli ◽  
D. K. Landstrom ◽  
W. C. Lane

Last year we reported on the use of reflected light interference microscopy (RLIM) for the direct color photography of the surfaces of living normal and malignant cell cultures without the use of replicas, fixatives, or stains. The surface topography of living cells was found to follow underlying cellular structures such as nuceloli, nuclear membranes, and cytoplasmic organelles, making possible the study of their three-dimensional relationships in time. The technique makes possible the direct examination of cells grown on opaque as well as transparent surfaces. The successful in situ electron microprobe analysis of the elemental composition and distribution within single tissue culture cells was also reported.This paper deals with the parallel and combined use of scanning electron microscopy (SEM) and the two previous techniques in a study of living and fixed cancer cells. All three studies can be carried out consecutively on the same experimental specimens without disturbing the cells or their structural relationships to each other and the surface on which they are grown. KB carcinoma cells were grown on glass coverslips in closed Leighto tubes as previously described. The cultures were photographed alive by means of RLIM, then fixed with a fixative modified from Sabatini, et al (1963).



1984 ◽  
Vol 45 (C2) ◽  
pp. C2-781-C2-784 ◽  
Author(s):  
P. Van Dyck ◽  
H. Storms ◽  
R. Van Grieken


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