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Fine earth

Soil (L, F, H, and A layers), mosses and fungal fruiting bodies were each collected from the same spots at the three locations. The L, F, H samples were ground to pass a 1 cm sieve the mineral soil was sieved to retain its fine-earth 2mm fraction mosses were separated into green versus dead tissues the fruiting bodies were separated by stalk and cap. Subsamples were freeze-dried prior to... [Pg.245]

Beatty, M. T. and Bonnichsen, R. (1994). Dispersing aggregated soils and other fine earth in the field for recovery of organic archaeological materials. Curr. Res. Pleist. 11, 73-74. [Pg.140]

By convention, soil analysis is done on fine earth . This is air-dried soil, ground and sieved through a 2 mm screen after removal of stones and roots larger than 2 mm diameter. Unfortunately there is not always an easy distinction between stones , weathered rock such as soft chalk and hard lumps of soil. So it may be difficult to standardise the preparation of the laboratory sample. [Pg.24]

Diatomaceous earth of varying permeability, as well as mixtures of diatomaceous earth and cellulose, make filtration through precoats suitable for a wide range of applications. Table 11.2 shows the clarification of a turbid white wine filtered through three different types of earth. Filtration behavior may be predicted by laboratory tests (Section 11.6.2). This type of filtration is generally restricted to untreated wines, as one of the first stages in clarification. However, currently available fine earths may also be used to prepare... [Pg.346]

Filtration throngh a coarse diatomaceous earth precoat (2.3 and 1.5 Darcy) did not affect chemical composition. The same operation with fine earth (0.35 Darcy) reduced the polysaccharide and condensed tannin content by 10%. No organoleptic effects were identified when the samples were tasted one month after filtration. [Pg.363]

Neither clarifying nor sterilizing flat-sheet filters cansed any more noticeable changes than fine earth filters. A reduction in fermentation esters was noted, althongh the terpenols in Muscat wines were unaffected. No significant differences were identified when the wines were tasted. [Pg.363]

For particle-size analysis, the fine earth was treated with 3 M HjOj and sonicated (15 min, 15 kHz) coarse, medium and fine sand were retrieved by sieving at 0.25, 0.10 and 0.05 mm, respectively silt was separated from clay by sedimentation after dispersion in 0.01 M NaOH. The pHjj g was measured potentio-metrically (solid/liquid ratio of 1 2.5). Organic C and total N were measured on acidified samples using a Carlo Erba NA1500 analyser. Available P was determined according to Olsen et al. (1954). Effective cation exchange capacity (ECEC) was determined by summation of the cations displaced with 0.2 M BaCl2 and analyzed by atomic absorption with a Perkin-Elmer llOOB spectrophotometer. [Pg.70]

Eor solution P-NMR analyses, samples of fine earth, washings and rock fragments from bulk, LAR and TAR of the 2C1 horizon were treated with 0.1 M NaOH solution (under N2 atmosphere, sofid/Uquid ratio, 1 10). After 24 h of shaking, the suspensions were centrifuged the supernatant was filtered at 0.45 pm, taken to pH < 4.0 (with 6 M HCl), and dialyzed at 100 Da molecular mass cut-off (Spectra/Por Biotec CE). The dialyzed extracts were freeze-dried and dissolved in 2 mL of 0.5 M NaOD. The P spectra were obtained using a 300-MHz NMR spectrometer (Varian VXR 300) operating at 121.4 MHz. [Pg.70]

To extract different forms of Ee, the clay fractions from the fine earth of bulk, LAR and TAR were dispersed in NaOH at pH 8.5 and treated with acidic (pH 3) NH4-oxalate (Blakemore et al., 1981), citrate-bicarbonate-dithionite (CBD) (Mehra and Jackson, 1960) and 0.1 M hydroxylamine hydrochloride (HAHC) (Chao, 1972). The Ee extracted was measured by atomic absorption with a Perkin-Elmer llOOB spectrophotometer. [Pg.70]

To investigate the presence of organo-mineral compounds, specimens of fine earth and the five separates (coarse, medium and fine sand, silt and clay) from bulk, LAR and TAR of the 2C horizons were shaken for 30 min in 1.2 M HCl solution (solid/liquid ratio, 1 10) the suspensions were centrifuged and the supernatants filtered at 0.45 pm. Aliquots of 2 mL were oven-dried (120°C) on glass slides and analyzed by X-ray diffraction using a Philips PW 1710 diffractometer (Fe-filtered Co-Kaj radiation). The acid extracts were also analyzed by gas chromatography, following the procedure of Ferntodez Sanjurjo et al. [Pg.71]

To assess the role of organic acids on the release of Ca, Mg, K and P, the fine earth from the bulk of the 2C horizons was treated with water and 500 pM oxalic acid solution (Jones and Darrah, 1994) for 1 h (solid/liquid ratio, 1 10). The released Ca, Mg and K were measured by atomic absorption, while P was determined according to Bray and Kurtz (1945). [Pg.71]

The amount of skeleton was around 100 g kg in the O horizons, and ranged between 554 and 409 g kg in the mineral horizons (Table 1). With the exception of the Oe horizon, the mineral part of which has a silt texture, in all the horizons the fine earth had a sandy texture, with a prevalence of coarse sand. The pH increased with increasing depth, reaching neutrality in the 2C horizons (Table 1). Organic C and total N were present in considerable amounts in the O and AC+A/C horizons, but became scarce in the 2E and 2C horizons. The ECEC followed the trend of organic C and total N, ranging from about 30 cmol(+) kg in the O horizons to 7-8 cmol(+) kg in the 2C ones. [Pg.71]

In the 2C horizons, the fine earth was the most abundant fraction on a volume basis in both bulk and LAR, whereas the rock fragments, and in particular those larger than 10 mm, were abundant in the TAR (Table 2). Still on a volume basis, the washings were present in amounts of less than 1%. [Pg.71]

The bulk density of the different fractions of bulk, LAR and TAR (Table 2) increased from fine earth and washings to skeleton and, in this last fraction, from the 2-A mm rock fragments to those > 10 mm, according to that previously described by Corti et al. (1998). The particle-size distribution of the fine earth from bulk and rhizosphere soil (Table 3) showed a relatively higher amount of clay in the TAR of both horizons. The pH of fine earth and washings tended to... [Pg.71]

Amounts of rock fragments, particle-size distribution of the fine earth, content of glass, pH in water, organic C and total N contents, and ECEC for the soil under Genista aetnensis at Mount Vetore (Sicily, Italy). Standard errors in parentheses (n = 2)... [Pg.72]

The P-NMR spectra (Fig. 3) showed an increase in the complexity of the signal patterns for all of the fractions from the bulk to the TAR. For the fine earth, the spectrum of the bulk only presented a signal in the area between 6.1 and... [Pg.74]

Fig. 3. liquid-state NMR spectra of the NaOH extracts obtained by fine earth, washing and rock fragments (2-A mm and > 10 mm) fractions from bulk, LAR and TAR of 2C1 horizon. Mount Vetore (Sicily, Italy). [Pg.75]

The diffraction patterns of the dried extract, obtained by treating the fine earth of bulk, LAR and TAR with 1.2 M HCl, did not display any peaks ascrib-able to oxalate minerals. The same happened with the separates of bulk and LAR, while fine sand and silt of the TAR showed peaks of calcium oxalate minerals ... [Pg.77]

Vetore the oxalates were mainly in the broom rhizosphere indicated that the roots were responsible for releasing oxalic acid. With respect to the Ca, Mg, K and P extracted from the bulk fine earth by water, the extraction with oxalic acid solution is from 2- to 32-fold higher, indicating that in this soil the excretion of oxalic acid from roots may represent a mechanism for the broom to take up nutrients through mineral alteration. Even though in small amounts, exudation of oxalic acid has contributed, together with the substances carried by the soil solutions through the roots, to the alteration of the minerals around the roots themselves. [Pg.79]

The A-ray diffraction patterns of the fine earth from bulk and rhizosphere soil (Fig. 6) confirmed the presence of calcite (peaks at 0.303, 0.229 and 0.209 nm) in both fractions of the 3Bw and 4BC horizons. In bulk and rhizosphere soil, primary minerals were represented by quartz (peaks at 0.335, 0.425 and 0.181 nm), plagio-clases (0.318, 0.320 and 0.326 nm), and micas (1.012 and 0.499 nm). Phyllosilicates comprised kaolinite (0.718 nm) and 2 1 clay minerals, with the interlayer occupied by hydroxy-Al polymers with varying degrees of polymerization (peak at 1.472 nm) among these minerals, the most represented was the hydroxy-Al interlayered vermiculite (HIV). In all horizons, diffractograms of the... [Pg.87]

Fig. 6. X-ray diffraction patterns of the fine earth from bulk and rhizosphere soil of the Selva di Gallignano (Ancona, Italy). The d-values are in nanometer. Fig. 6. X-ray diffraction patterns of the fine earth from bulk and rhizosphere soil of the Selva di Gallignano (Ancona, Italy). The d-values are in nanometer.
Agnelli, A., Celi, L., Degl Innocenti, A., Corti, G., Ugohni, F.C., 2002. The changes with depth of humic and fulvic acids extracted from fine earth and rock fragments of a forest soil. Soil Sci. 167, 524-538. [Pg.119]

Fuller s earth Absorbents 3.2 Textile workers (or fullers ) cleaned raw wool by kneading it in a mixture of water and fine earth, which adsorbed oil, dirt, and other contaminants... [Pg.349]

The types of material include bedrock and soil (including artificial fill). Soils are described as material that is either predominantly coarse (debris) or predominantly fine (earth). [Pg.37]


See other pages where Fine earth is mentioned: [Pg.148]    [Pg.229]    [Pg.38]    [Pg.115]    [Pg.356]    [Pg.67]    [Pg.70]    [Pg.73]    [Pg.73]    [Pg.73]    [Pg.73]    [Pg.73]    [Pg.73]    [Pg.74]    [Pg.75]    [Pg.76]    [Pg.77]    [Pg.3501]    [Pg.91]    [Pg.950]    [Pg.241]   
See also in sourсe #XX -- [ Pg.8 ]




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