Journal articles on the topic 'Red-brown earth'
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1
Chartres, CJ, RW Cumming, JA Beattie, GM Bowman, and JT Wood. "Acidification of soils on a transect from plains to slopes, south western New-South-Wales." Soil Research 28, no. 4 (1990): 539. http://dx.doi.org/10.1071/sr9900539.
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Samples were collected from unimproved road reserves and adjacent paddocks on a 90 km transect crossing red-brown earth soils in the west and red earth soils in the east. Measurements of pH in water and CaCl2 indicated that the red earths have been acidified by approximately 0.5 pH units over the last 30-40 years. Small increases in CaCl2-extractable A1 were also recorded for the acidified red earths. The red-brown earths do not appear to have been markedly affected by soil acidification to date. Clay mineralogical data and measurements of cation exchange capacity of the <2 �m fraction indicate that red-brown earths are better buffered against acidification than red earths. However, small differences in management practices and rainfall along the transect may also be partially responsible for differences in acidification between soil types.
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French, RJ, and MA Ewing. "Soil type influences the relative yields of different cereals and crop legumes in the Western Australian wheatbelt." Australian Journal of Experimental Agriculture 29, no. 6 (1989): 829. http://dx.doi.org/10.1071/ea9890829.
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Crop choice depends on the relative yields of different species, and will vary according to soil type and seasonal conditions. Crop legumes are a relatively new component of agriculture in southern Australia, especially on the drier fringe of the agricultural areas. In this study wheat, barley, field peas and narrow-leafed lupin were compared at Merredin, Western Australia (mean annual rainfall 310 mm) from 1984 to 1986 on a red brown earth, a solonised brown soil, a solodic soil and, in 1984 and 1985, on an acid earthy sand. Oats, cereal rye and triticale were included in 1984, and chickpeas in 1984 and 1986. Highest mean seed yields were produced on the red brown earth and solonised brown soil, although the red brown earth produced very low yields in a dry season. Lowest yields were produced on the earthy sand. Triticale, oats and cereal rye yielded less seed than wheat or barley on all soils except the earthy sand where triticale yielded more than wheat. Legumes yielded less seed than cereals, although the yield for peas was close to that for wheat on the red brown earth. Peas yielded more than lupins or chickpeas on all soils. Lupin yield was closest to pea yield on the solodic soil and earthy sand. A separate series of experiments comparing peas and lupins in different seasonal conditions but on similar soils showed that lupins yielded more than peas when growing season rainfall was high. Peas are the most suitable crop legume for the Merredin area on all fine-textured soils. Lupins remain the choice on coarse-textured soils until pea stubbles can be managed to minimise erosion. In wetter areas lupins are a better choice on coarse-textured soils.
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Rengasamy, P., RSB Greene, and GW Ford. "Influence of magnesium on aggregate stability in sodic red-brown earths." Soil Research 24, no. 2 (1986): 229. http://dx.doi.org/10.1071/sr9860229.
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Studies on sodium clay separated from a red-brown earth demonstrated that higher concentrations of magnesium salts than calcium salts were required for flocculation. Statistical analysis of the data from a range of red-brown earths showed that the dispersion of clays from soils with an SAR1:5 >3 increased as the Ca/Mg ratio of 1:5 soil-water extracts decreased below unity. The hydraulic conductivity of columns of <2 mm surface and subsurface samples from one red-brown earth was significantly reduced when Ca/Mg ratios in the percolating solutions were below unity only when the SAR was above 3 and the TCC (total cation concentration) values were less than the predicted flocculation values. When the TCC values of the percolating solution exceeded the flocculation values, hydraulic conductivity was not affected by either SAR or Ca/Mg ratio. If structural problems in sodic soils containing high levels of exchangeable magnesium (e.g. Ca/ Mg < 1) are to be minimized, it is necessary to maintain an electrolyte level above the threshold value for a particular soil. In red-brown earths the specific effect of magnesium is so small that for magnesium-dominant soils an additional gypsum application of 1 t ha-1 for the surface 10 cm of soil should be sufficient.
4
Bernas, SM, JM Oades, and GJ Churchman. "Effects of latex and poly-DADMAC on erosion, hydrophobicity and water-retention on two different soils." Soil Research 33, no. 5 (1995): 805. http://dx.doi.org/10.1071/sr9950805.
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Latex (natural polymer) and poly-DADMAC (synthetic polymer) were applied to a red brown earth (Alfisol) and a Wiesenboden (Mollisol). Run-off, infiltration, sediment loss and water stable aggregates were measured after subjecting the soils to simulated rainfall. Water retention of latex and poly-DADMAC amended soils was determined. The MED test for hydrophobicity was also carried out for the latex-treated soil. Latex decreased run-off and erosion, and increased infiltration on both soils. Poly-DADMAC minimized run-off and erosion, and increased infiltration on the Wiesenboden. It increased run-off and decreased infiltration on the red-brown earth; however, it still decreased erosion. Latex increased the percentage of water-stable aggregates > 2 mm on the red-brown earth, but it had less effect on the Wiesenboden. Poly-DADMAC decreased the percentage of water-stable aggregates < 0.125 mm on both soils after simulated rainfall. Both latex and poly-DADMAC had little effect on water retention of the red-brown earth and the Wiesenboden. Application of 1.5 g kg-1 of latex increased MED values of both soils, to give values that indicate moderate water-repellence but should not affect plant growth. Generally, latex was more effective on the red-brown earth and poly-DADMAC was more effective on the Wiesenboden. It seems that latex can be effective on all soil types, but poly-DADMAC will have more effect on clay soils.
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Slattery, WJ, and DR Coventry. "Response of wheat, triticale, barley, and canola to lime on four soil types in north-eastern Victoria." Australian Journal of Experimental Agriculture 33, no. 5 (1993): 609. http://dx.doi.org/10.1071/ea9930609.
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Lime requirement curves based on relative yield and pH data for 4 soil types were derived to estimate the amount of lime required to reach maximum yield for wheat, triticale, barley, and canola. Simple equations expressing lime requirement as a function of soil pH accounted for >90% of the variation in applied lime on 3 soil types (red brown earth, red podsolic, podsolised red earth). When aluminium and manganese (0.01 mol CaCl2/L extracted) were included in these equations, either individually or together, they did not improve the relationship significantly for these 3 sites; however, manganese significantly improved the predictability of lime for solodic soil. A comparison of this model with a laboratory-based model showed good correlation for 3 soils (red brown earth, red podsolic, podsolised red earth), but the laboratory method underestimated the field lime requirement of solodic soil.
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Monrós, Guillermo, José A. Badenes, and Mario Llusar. "Ecofriendly High NIR Reflectance Ceramic Pigments Based on Rare Earths Compared with Classical Chromophores Prepared by DPC Method." Ceramics 5, no. 4 (September 20, 2022): 614–41. http://dx.doi.org/10.3390/ceramics5040046.
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A high NIR reflectance ceramic pigments palette based on rare earths except black (La,Li-SrCuSi4O10 blue wesselsite, Pr-CeO2 red-brown cerianite, Mo-Y2Ce2O7 yellow cerate, Sr4Mn2CuO9 black hexagonal perovskite) was compared with the coolest traditional pigments palette prepared by dry powder coating (DPC) to obtain “core-shell” pigments (Co-willemite blue, Cr-franklinite brown, Ni,Sb-rutile yellow, Co,Cr-spinel black). Adding CaCO3 as a binder, normalized NIR reflectance at L* = 85, 55 and 30 was compared for yellow, brown and blue-black powders, respectively. Rare earths lack intense absorption bands in the NIR range and therefore its pigments show higher NIR reflectance, but normalized measurements show smaller differences and even have an inverse result for blue pigments. The pigmenting capacity and stability study in different media show that the stability of cool rare earth pigments is lower than that of DPC classical pigments, except in the case of the red-brown Pr-cerianite pigment.
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Slavich, PG, BJ Read, and BR Cullis. "Yield response of barley germplasm to field variation in salinity quantified using the EM-38." Australian Journal of Experimental Agriculture 30, no. 4 (1990): 551. http://dx.doi.org/10.1071/ea9900551.
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Five field trials to screen a range of barley germplasm for tolerance to saline soil conditions were conducted on irrigation farms in southern New South Wales, in areas affected by secondary salinisation from shallow watertables. Three trials were located on heavy grey clay soils and 2 on red-brown earth soils. An electromagnetic soil conductivity meter (EM-38) was used to quantify the salinity of individual field plots. Cultivars were compared in terms of their grain yield response to soil salinity. Yields were significantly reduced by soil salinity at all sites except 1 on red-brown earth. Both genetic and site differences in salinity response were identified. The reduction in yield per unit increase in electrical conductivity of the saturated paste (EC,), averaged across sites, varied from 4.7% for Forrest to 6.6% for Schooner. However, the yield reduction per unit increase in EC,, averaged across cultivars, varied from 4.1% in a red-brown earth to 6.4% in heavy clays.
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Ellington, A., N. S. Badawy, and G. W. Ganning. "Testing gypsum requirements for dryland cropping on a Red-Brown Earth." Soil Research 35, no. 3 (1997): 591. http://dx.doi.org/10.1071/s96068.
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Gypsum requirements of a Red-Brown Earth used for dryland cropping were determined by 2 methods: those of the State Chemistry Laboratory (SCL) and of the Institute for Sustainable Irrigated Agriculture (ISIA). These are based, respectively, on exchangeable cations of soil by the Tucker method, and on water-soluble cations in a 1:5 water extract of soil. Information was also gained on longevity of gypsum effects on soil. Gypsum was applied to plots at rates 0·5, 1, and 2 times that predicted by ISIA, whereas the SCL method predicted that no gypsum was required. After 2 years, plots were split and the 3 rates of gypsum were either applied to soil previously untreated with gypsum, or re-applied to the soil treated 2 years before. According to the SCL test, the 0–10 cm soil depth of the Red-Brown Earth was not sodic (ESP <6), it was slightly magnesic (EMgP >25), and required no gypsum. However, it was found that gypsum lowered ESP, EMgP, and clay dispersion, with some effects extending into the 10–20 cm soil depth. With the ISIA method, the 0–10 cm soil depth was classed as low-sodic, but potentially dispersive; it required 2·5 t/ha of gypsum if soil was cultivated, but no gypsum if it was direct-drilled or was under pasture. One year after application, only the highest rate of gypsum (5 t/ha) significantly (P < 0·001) raised the electrolyte concentration of the soil suspension, although all rates reduced (P < 0·001) SAR, and the 2 higher rates reduced (P < 0·01) clay dispersion. However, these effects had disappeared after Year 3. There were significant increases in crop yields due to gypsum treatment in Year 1 (0·5–0·9 t/ha, P < 0·01) and Year 2 (0·3 t/ha, P < 0·001), but no response in Year 3. Fungal diseases seemed to reduce wheat responses, and the highest rate of gypsum caused chlorosis of lupins. Judging by crop performance, the ISIA method predicted an optimal rate of gypsum for the 0–10 cm layer of this soil type. The SCL prediction was also only for the 0–10 cm layer, but had it been used for deeper layers in the profile (the original intention for the technique), it would have given a recommendation not very different from the ISIA method.
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Xu, Shuang, Chongyang Shen, Xueyong Zhang, Xijuan Chen, Mark Radosevich, Siqun Wang, and Jie Zhuang. "Mobility of Cellulose Nanocrystals in Porous Media: Effects of Ionic Strength, Iron Oxides, and Soil Colloids." Nanomaterials 10, no. 2 (February 18, 2020): 348. http://dx.doi.org/10.3390/nano10020348.
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Understanding the dispersivity and migration of cellulose nanocrystals (CNCs) in porous media is important for exploring their potential for soil and water remediation. In this study, a series of saturated column experiments were conducted to investigate the coupled effects of ionic strength, iron oxides (hematite), and soil colloids on the transport of CNCs through quartz sand and natural soils (red earth and brown earth). Results showed that CNCs had high mobility in oxide-free sand and that iron oxide coating reduced the mobility of CNCs. An analysis of Derjaguin-Landau-Verwey-Overbeek interactions indicated that CNCs exhibited a deep primary minimum, nonexistent maximum repulsion and secondary minimum on hematite-coated sand, favorable for the attachment of CNCs. The maximum effluent percentage of CNCs was 96% in natural soils at 5 mM, but this value decreased to 4% at 50 mM. Soil colloids facilitated the transport of CNCs in brown earth with larger effect at higher ionic strength. The ionic strength effect was larger in natural soils than sand and in red earth than brown earth. The study showed that CNCs can travel 0.2 m to 72 m in porous media, depending on soil properties, solution chemistry, and soil colloids.
10
Dalal, RC, and RJ Mayer. "Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. II. Total organic carbon and its rate of loss from the soil profile." Soil Research 24, no. 2 (1986): 281. http://dx.doi.org/10.1071/sr9860281.
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The kinetics of organic C loss were studied in six southern Queensland soils subjected to different periods (0-70 years) of cultivation and cereal cropping. The equation: Ct = Ce + (C0 - Ce)exp(- kt), where C0, Ce and C, are organic C contents initially, at equilibrium and at time k respectively, and k is the rate of loss of organic C from soil, was employed in the study. The parameter k was calculated both for %C (kc) and for weight of organic C/volume of soil (k,), determined by correcting for differences in sampling depth due to changes in bulk density upon cultivation. Mean annual rainfall largely determined both C, and Ce, presumably by influencing the amount of dry matter produced. Values of kc and kw varied greatly among the soils studied. For the 0-0.1 m depth, kw was 0.065, 0.080, 0.180, 0.259, 0.069 and 1.224 year-1 respectively for Waco (black earth - initially grassland), Langland-Logie (grey brown and red clays - brigalow), Cecilvale (grey, brown and red clays - poplar box), Billa Billa (grey, brown and red clays - belah), Thallon (grey, brown and red clays - coolibah) and Riverview (red earths - silver-leaved ironbark). The k values were significantly correlated with organic Chrease activity ratio (r = 0.99***) and reciprocal of clay content (r = 0.97**) of the virgin soils. In stepwise multiple regression analysis, aggregation index (for kc values) or exchangeable sodium percentage (for kw) and organic C/urease activity ratio of soils were significantly associated with the overall rate of loss of organic C. It was inferred, therefore, that the relative inaccessibility and protection of organic matter against microbial and enzymic attack resulted in reduced organic C loss. Losses of organic C from the deeper layers (0-0.2 m, 0-0.3 m) were observed in Waco, Langlands-Logie, Cecilvale and Riverview soils, although generally rate of loss decreased with depth.
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Jessop, RS, DA Macleod, PJ Hulme, and DC Mckenzie. "The effects of landforming on crop production on a red-brown earth." Soil Research 23, no. 1 (1985): 85. http://dx.doi.org/10.1071/sr9850085.
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Crop growth on the exposed subsoils of Macquarie Valley red-brown earths, which have been levelled for flood irrigation development, is much less than on undisturbed and fill areas. A project was carried out to quantify the differences in properties between topsoil and exposed subsoil and to relate these differences to observed crop performance. Cotton growth was measured on cut (surface soil removed) and fill (additional surface soil added from cut areas) sites. Soil samples were collected from both sites for chemical and physical analysis. To supplement these measurements pot experiments were conducted using cut and fill soils, a mixture of the two to simulate mixing in the field, all with or without gypsum. In the field, cotton growth on the cut soil was less than half that on the fill due to lower emergence and slower subsequent growth. Pot experiments confirmed these differences, although the surface structural problems were exacerbated by the rapid wetting of soil in pots. Differences between the surface of the cut and fill soils were attributed to the poorer development and lower stability of structure in the exposed subsoil. Below 30 cm, ESP, EMgP and Dispersion Index were higher in the cut than in the fill sites; ECaP and pH were lower. The pot experiments indicated that mixing of topsoil and subsoil improved emergence and subsequent growth, compared with the exposed subsoil, but gypsum had no significant ameliorative effect.
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Cook, F. J., N. S. Jayawardane, and J. Blackwell. "Effects of amelioration on infiltration characteristics of a transitional red-brown earth." New Zealand Journal of Crop and Horticultural Science 17, no. 2 (April 1989): 183–88. http://dx.doi.org/10.1080/01140671.1989.10428029.
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Wright, G. C., and C. J. Smith. "Soybeans root distribution under wet soil culture on a red-brown earth." Plant and Soil 103, no. 1 (March 1987): 129–33. http://dx.doi.org/10.1007/bf02370678.
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Dalal, RC, and RJ Mayer. "Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. I. Overall changes in soil properties and trends in winter cereal yields." Soil Research 24, no. 2 (1986): 265. http://dx.doi.org/10.1071/sr9860265.
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Changes in fertility of some southern Queensland soils resulting from extended periods of cultivation are presented, together with trends in yields of winter cereals on these soils. Six major soils of the cereal-belt, cropped for maximum periods of 20-70 years were examined. These were: Black earths, Waco soil; grey, brown and red clays (brigalow), Langlands-Logie soil; grey, brown and red clays (poplar box), Cecilvale soil; grey, brown and red clays (belah), Billa Billa soil; grey, brown and red clays (coolibah), Thallon soil; red earths, Riverview soil. Organic matter and its constituents, especially total organic C, organic C in the light fraction, total N and mineralizable N, were affected most by cultivation, showing decreases of 19-67% overall. Other soil properties probably associated with organic matter, including bulk density and DTPA (diethylenetriaminepentaacetic acid) extractable manganese, were also significantly affected by cultivation in all soils. Soil properties affected least by cultivation were concentrations of inorganic phosphorus, total and exchangeable potassium, calcium carbonate, and dithionite extractable iron and aluminium. Most other soil properties studied (organic P, total sulfur, pH, exchangeable magnesium and sodium, exchangeable sodium percentage, and oxalate-extractable iron and aluminium) were affected by cultivation in at least four soils. Four factors accounted for 70% of the total variation among the 45 soil properties considered. They appeared to represent organic matter, clay colloids, iron and aluminium oxides, and soluble salts. Dry matter yield and/or N uptake of winter cereal crops (wheat and barley) measured in 1983 showed significant decreasing trends with period of cultivation in all soils.
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Cavanagh, PP, AJ Koppi, and AB Mcbratney. "The effects of minimum cultivation after three years on some physical and chemical properties of a red-brown earth at Forbes, NSW." Soil Research 29, no. 2 (1991): 263. http://dx.doi.org/10.1071/sr9910263.
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Reducing cultivation may improve many soil physical and chemical properties of a red-brown earth. A trial was set up in 1986 on a red-brown earth near Forbes, N.S.W., comparing direct-drilling and conventional-cultivation crop establishment techniques. The surface soil (0-100 mm) was sampled at the end of the third year and assessed for macropore structure, infiltration characteristics, bulk density, pH, electrolytic conductivity, organic carbon and total nitrogen content. Cultivation degraded some desirable soil physical properties as indicated by data obtained from image analysis and infiltration. Bulk density did not mirror differences in macroporosity. Organic carbon, total nitrogen and electrolytic conductivity levels were higher in direct-drilled soil in comparison to conventionally tilled soil. It ib concluded that the improvement of soil chemical and physical properties afforded by a reduction in tillage would lead to an increase in soil water infiltration rate and storage.
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Cavanagh, PP, AJ Koppi, and AB Mcbratney. "Corrigenda - The effects of minimum cultivation after three years on some physical and chemical properties of a red-brown earth at Forbes, NSW." Soil Research 29, no. 2 (1991): 263. http://dx.doi.org/10.1071/sr9910263c.
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Reducing cultivation may improve many soil physical and chemical properties of a red-brown earth. A trial was set up in 1986 on a red-brown earth near Forbes, N.S.W., comparing direct-drilling and conventional-cultivation crop establishment techniques. The surface soil (0-100 mm) was sampled at the end of the third year and assessed for macropore structure, infiltration characteristics, bulk density, pH, electrolytic conductivity, organic carbon and total nitrogen content. Cultivation degraded some desirable soil physical properties as indicated by data obtained from image analysis and infiltration. Bulk density did not mirror differences in macroporosity. Organic carbon, total nitrogen and electrolytic conductivity levels were higher in direct-drilled soil in comparison to conventionally tilled soil. It ib concluded that the improvement of soil chemical and physical properties afforded by a reduction in tillage would lead to an increase in soil water infiltration rate and storage.
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Tisdall, J. M., and H. H. Adem. "Mechanized relay-cropping in an irrigated red-brown earth in south-eastern Australia." Soil Use and Management 6, no. 1 (March 1990): 21–27. http://dx.doi.org/10.1111/j.1475-2743.1990.tb00791.x.
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Cook, F. J. "Effects of gypsum slotting on the hydraulic properties of a red-brown earth." Soil and Tillage Research 28, no. 3-4 (January 1994): 239–52. http://dx.doi.org/10.1016/0167-1987(94)90133-3.
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Dalal, RC, and RJ Mayer. "Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland .V. Rate of loss of total nitrogen from the soil profile and changes in carbon : nitrogen ratios." Soil Research 24, no. 4 (1986): 493. http://dx.doi.org/10.1071/sr9860493.
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The kinetics of total N loss from the top (0-0.1 m) and the subsoil (up to 1.2 m depth) of six southern Queensland soils after different periods (0-70 years) of cultivation and cereal cropping, were studied. The equation: Nt = Ne + (No - N,)exp(- kt), where No, Ne and N, are total N concentrations initially, at equilibrium and at time t, respectively, and k is the rate of loss of total N from soil, described total N loss from only three soils. For the 0-0.1 m depth, the kw values (based on weight of total Nholume of soil) were 0.061, 0.115 and 0.275 year-1, respectively for Waco (black earth; initially grassland), Langlands-Logie (grey, brown and red clays; brigalow) and Cecilvale soil (grey, brown and red clays; poplar box). The kw values decreased to less than half at 0-0.6 m depths of those at 0-0.1 m depth. In the other three soils, Billa Billa (grey, brown and red clays; belah), Thallon (grey, brown and red clays; coolibah) and Riverview (red earth; silver-leaved ironbark), total N declined linearly over the 20-25 years of cultivation period studied. Average annual rates of N loss from the profiles of the six soils, respectively, were 31.3, 67.1, 34.5, 50.8, 35.8 and 32.0 kg N ha-1 year-1 , from Waco, Langlands-Logie, Cecilvale, Billa Billa, Thallon and Riverview soils. Except for Langlands-Logie, these losses could be accounted for by crop N removal. In the Langlands-Logie soil, besides N removal by crop (51 kg N ha-1 year-1, 1982-1984 period), leaching of N below the root-zone appeared to be the likely factor for N loss. C:N ratios generally increased with depth in the five clay soils but decreased with depth in the red earth (Riverview). Cultivation had no significant effect on the C:N ratios of Cecilvale, Thallon and Riverview soils, but it caused a decrease in Langlands-Logie soil (up to 0.6 m depth) and an increase in Waco soil (up to 1.2 m depth). It was inferred, therefore, that in the latter, remaining soil N was likely to mineralise more slowly with increasing period of cultivation, resulting in a fertility loss which may be greater than that shown by the decrease in total N.
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Baldock, JA, M. Aoyama, JM Oades, o. Susant, and CD Grant. "Structural amelioration of a South Australian red-brown earth using calcium and organic amendments." Soil Research 32, no. 3 (1994): 571. http://dx.doi.org/10.1071/sr9940571.
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The ability of wheat straw, gypsum and agricultural lime to ameliorate the unstable structural condition of a degraded red-brown earth located at the Waite Agricultural Research Institute, South Australia, was investigated in a field experiment lasting 5 years. Wheat straw was added at rates of 0, 5 and 10 t ha-1 y-1, and gypsum and agricultural lime were added at rates of 3.4 and 2.0 t ha-1 y-1 respectively. Most of the measurements were taken on samples collected after three and four consecutive years of treatment applications, but some were taken one year after the fifth and final application of the treatments. The amount of water-stable macroaggregation in the top 10 cm increased with increasing rate of wheat straw application. Addition of agricultural lime incorporated with straw temporarily increased macroaggregate stability to a greater extent than was observed with either amendment alone. The proportion of the soil surface occupied by macropores was also increased significantly by addition of agricultural lime, and this was attributed to a stimulation of biological activity in the soil due to the increased soil pH. Density fractionation of the soil suggested the turnover of the added wheat straw in the lime-treated soil was greater than in the gypsum-treated and control soils. Addition of gypsum decreased the content of mechanically dispersible clay by modifying the electrolyte concentration and composition, but was unable to completely resist the dispersive tendencies created by the decomposing organic residues. The high rates of wheat straw incorporated in the top 10 cm caused significant dispersion in the top 20 cm, which was thought to have mobilized clay particles causing them to move downward, resulting in pore blockage and the consequent lowering of hydraulic conductivity in the zone immediately below.
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Chelnokova, Marina I., and Andrey A. Chelnokov. "Features of development of visceral organs in embryos of egg cross chickens ‘Lohmann Brown’ under red and green monochromatic LED lighting." RUDN Journal of Agronomy and Animal Industries 17, no. 1 (April 2, 2022): 112–23. http://dx.doi.org/10.22363/2312-797x-2022-17-1-112-123.
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New data on the features of development of visceral organs in embryos of egg cross chickens Lohmann Brown under red and green monochromatic LED lighting were obtained. The effect of two continuous LED lighting modes has been studied: experimental modes - r ed and green light, control - d arkness. The absolute values of weight dimensions and specific growth rate (according to the Schmalhausen-Brody formula) of heart, muscular stomach, liver of chicken embryos were estimated using morphometric methods. The studies proved that red and green LED lighting has a stimulating effect on the embryonic development of visceral organs (heart, muscular stomach, liver) in Lohmann Brown egg cross compared to the control (darkness). Under red and green LED stimulation, chicken embryos prevailed in the heart mass from the 14th to the 20th day of embryogenesis. The muscular stomach and liver of chicken embryos developed more intensively under red illumination on the 18th and 20th days, and under green illumination - a similar effect on the muscular stomach was noted on the 19th and 20th days, on the liver - o n the 20th day. It has been established that in the early ontogenesis of Lohmann Brown chickens there were several critical stages (phases). They fall on different days of development and characterize the features of rhythmicity in growth processes of visceral organs in chicken embryogenesis under LED stimulation of red and green spectrum. Chicken embryos under red and green illumination had the highest growth rate of heart on the 17th and 20th day, respectively; muscular stomach under red illumination - o n the 17th and 20th days, liver - on the 16th and 17th day under red and green illumination. By the hatching period on the 20th day, there were no differences in the development of visceral organs of chicken embryos depending on red and green light spectrum. The hatching of Lohmann Brown chicken embryos exposed to red and green light occurred on the 20th day of incubation - a day earlier than under control conditions (darkness). The proposed biological causes underlying the effect of monochromatic light of different color spectrum on embryogenesis of chicken embryo and organs are discussed.
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Skourtsis-Coroneou, Vassiliki. "Palaeonubecularia trifonovae n. sp. (? Foraminifera) from the Ladinian – Carnian of the Epidaurus, “Hallstatt” facies, Peloponnesus (Greece)." Geologica Balcanica 25, no. 5-6 (December 30, 1995): 75–78. http://dx.doi.org/10.52321/geolbalc.25.5-6.75.
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Jayawardane, NS, and WS Meyer. "Measuring air-filled porosity changes in an irrigated swelling clay soil." Soil Research 23, no. 1 (1985): 15. http://dx.doi.org/10.1071/sr9850015.
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An in-situ method for measuring air filled porosity (�a) of soils using a neutron meter was developed and evaluated for a layered, swelling clay soil. Bulk density-volumetric moisture content relationships of soil layers were used to calculate the regressions of volumetric moisture content on �a. These regressions were combined with calibration equations of the neutron meter to obtain relationships between �a and neutron counts. The �a values predicted from measured neutron count ratios show good agreement with �a values calculated from the measured bulk densities and moisture contents in a transitional red-brown earth. The method provides a rapid and non-destructive measurement of �a. Soil aeration in a transitional red-brown earth under two irrigation treatments was assessed using neutron counts to monitor the changes in �a profiles. Large soil cores which were flooded had lower profile �a values than did cores which were not flooded. However, differences were small, owing apparently to the very low rates of infiltration and redistribution. The potential use of this method to continuously monitor changes in �a profiles allows frequent calculation of aeration stress indices, which may be used to predict crop responses and yield losses due to poor aeration.
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Emerson, WW. "Structural decline of soils, assessment and prevention." Soil Research 29, no. 6 (1991): 905. http://dx.doi.org/10.1071/sr9910905.
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Two extreme textural types of cultivated surface soils are mainly considered here, non-shrinking red-brown earths and highly shrinking cracking clays. Total porosity is used to assess the structural status of the former. Values are compared with the highest and lowest values found in the field. For the latter, the criterion used is the porosity of dry aggregates or clods. Values here are taken from the literature. To find out why inter-particle bonding in soil aggregates is insufficient to stop structural decline, a scheme has been developed which includes a modified version of Emerson's (1967) classification of soil aggregates. Slaking is carefully assessed. The bulk density of a cube made from soil at 'field capacity' is measured as well as testing another for dispersion. Class 3 is now divided into 3a and 3b, according to the degree of dispersion of remoulded soil in water. Also apart from soils which disperse spontaneously from dry, classes 1 and 2, the dispersion of all soils is assessed after remoulding at 'field capacity'. It has been found that the red-brown earth site which had the best visual structure also had the largest total porosity and aggregates in class 4. At the worst site, aggregates were in class 3a and the porosity had been reduced to that of the soil cube. For cracking clays, porosity is appreciably higher where the aggregates are in class 4 rather than class 3a. Water content/dispersion curves are presented for the clays showing the extent of the increase in OD apparently associated with the presence of carbonate. Dispersion of sheared, class 3a soil immersed in water is only an outward sign of the structural damage caused when the soil is sheared too wet. If the soil is dried instead, porosity is still lost. Mechanisms are suggested by which the structure of class 3a clay soils are improved by adding carbonate. The slumping of red-brown earths and the use of surface dressings of gypsum to prevent severe dispersion after cultivation wet are discussed. The structural stability of aggregates in the other five classes is briefly considered. Classes 1 and 2 require an ameliorant to be added, the rest pose few problems.
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Rovira, AD, KRJ Smettem, and KE Lee. "Effect of rotation and conservation tillage of earthworms in a red-brown earth under wheat." Australian Journal of Agricultural Research 38, no. 5 (1987): 829. http://dx.doi.org/10.1071/ar9870829.
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The effects of two rotation and two tillage systems on earthworm populations have been studied in a red-brown earth under wheat. At the time of sampling, the earthworm population under direct drill was nearly double that under conventional cultivation. The total number of worms was not affected by crop rotation with pasture or lupins, but following pasture there were significantly more large worms. It is suggested that at this site the earthworm population may be responding rapidly to alterations in food supply and water stress under the different agricultural systems.
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Kelly, KB, SJ Blaikie, WK Mason, and FM Martin. "Methods of increasing pasture growth on subsoil of a red-brown earth exposed by landforming." Australian Journal of Experimental Agriculture 29, no. 3 (1989): 369. http://dx.doi.org/10.1071/ea9890369.
Full textAbstract:
Subsoils are often exposed during landforming for flood irrigation. Pasture growth on subsoil of red-brown earth soils is generally poor. Two ungrazed experiments were conducted on these soils to evaluate methods of increasing productivity of established pasture (experiment 1) and newly sown pasture (experiment 2) on areas of exposed subsoil. Pasture production, soil water status and soil strength were measured. In experiment 1, pasture yield was increased by more frequent irrigation and any soil modification which increased the intake or availability of water. During the irrigation season there was a positive response to applied nitrogen wherever soil water supply was increased. During the rainfed period pasture production was increased by soil modification, nitrogen and by high rates of phosphorus. Total annual yield was increased from 9.1 t/ha at district levels of input to 14.6 t/ha where inputs were maximised. The best yield was only 80% of published values for pasture production on undisturbed areas in the Goulburn Valley. In experiment 2, organic matter (50 t/ha) and replacement of topsoil (75 mm) increased yield by 17 and 47% respectively. However, the positive effect of organic matter on yield persisted for only 10 months after application. Topsoil replacement was the only treatment to restore pasture production to levels previously published.
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McDonald, GK. "Growth of field pea on red-brown earth soils in a year with high rainfall." Australian Journal of Experimental Agriculture 35, no. 5 (1995): 619. http://dx.doi.org/10.1071/ea9950619.
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A study of 4 commercial crops of peas was conducted in the Lower North of South Australia during 1992 to assess the importance of waterlogging on growth and yield. The area chosen for the survey has a high proportion of red-brown earth soils that slake and seal, have poor internal drainage, and are prone to transient waterlogging. Rainfall in the year of the survey was above average, particularly during September and October, and waterlogging and disease were common in pea crops throughout the region. Based on air-filled porosity and soil water tension, waterlogging occurred in each of the survey paddocks. Differences in vegetative growth and grain yields within and between paddocks could be related to the severity of waterlogging. There were differences between the 4 survey paddocks for concentrations of potassium, sodium, iron, and manganese in pea shoots, and these differences appeared to correspond to differences in the severity of waterlogging. Nutrient concentrations were, however, confounded by differences in soil pH and soil fertility. Despite adequate to high levels of available phosphorus (P) in each of the 4 paddocks, concentrations of P in shoots were generally low and, in 2 cases, indicated P deficiency. Phosphorus concentrations were not related to the concentration in the soil or to the severity of waterlogging. In field experiments conducted over 2 seasons (1991, 1992), peas were grown in raised hill plots to promote drainage around the upper root system. The method significantly increased plant establishment in both years, and in 1992, a year of record high rainfall, grain yields from the drained plots were 5-64 times greater than those from undrained plots. In 1991, a year with lower rainfall, drainage improved pod yield by 13%. Observations during the survey suggested that disease was worse in the paddocks that were severely affected by excess water.
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Smith, C. J., D. M. Whitfield, O. A. Gyles, and G. C. Wright. "Nitrogen fertilizer balance of irrigated wheat grown on a red-brown earth in Southeastern Australia." Field Crops Research 21, no. 3-4 (July 1989): 265–75. http://dx.doi.org/10.1016/0378-4290(89)90008-7.
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Tisdall, JM. "Earthworm activity in irrigated red-brown earths used for annual crops in Victoria." Soil Research 23, no. 2 (1985): 291. http://dx.doi.org/10.1071/sr9850291.
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Few earthworms were found in January (15 m-2) or September (21 m-2) 1983 in surveys of irrigated soils used commercially for pastures in the Goulburn Valley, Vic.; only the introduced lumbricids were found. No earthworms were found in January 1983 in a survey of irrigated annual crops on similar soils; the soils had each supported irrigated pasture the previous year. However, in carefully managed experimental soils, i.e. with at least 10 t ha-' of cow manure added per crop with mild or no cultivation, used for double-cropping or lucerne, relatively high numbers (up to 86 m-2) of earthworms were present; these included lumbricids, the genera which are usually the most useful in terms of soil structure, and the native megascolecids. No mature lumbricids were found in January in plots without cow manure. Ample food is needed to enable relatively high numbers of lumbricids to develop in row-crops in the Goulburn Valley, and for very high numbers, the surface soil should be kept moist throughout summer. Macroporosity (20-80 mm depth), infiltration and number of biopores (50 mm depth) were each higher in the non-cultivated systems with cow manure than in the cultivated control (no cow manure added). Numbers of biopores in January 1984 were directly related to total numbers of earthworms in January 1984.
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Lorimer, MS, and LA Douglas. "Effect of management practice on properties of a Victorian red-brown earth .1. Soil physical-properties." Soil Research 33, no. 5 (1995): 851. http://dx.doi.org/10.1071/sr9950851.
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The effects of five management practices (native forest, native pasture, Phalaris pasture, crop-pasture rotation, continuous cropping), that had been in place for 18 years, on some soil physical properties of a red-brown earth near Bendigo, Victoria, were studied. Particle size distribution, bulk density and hydraulic conductivity of soil in the A and B horizons at different, management sites were measured. Where cultivation had occurred, soil in the A horizon contained less silt and clay, and more fine sand and coarse sand. The bulk density of the A horizon of soil that had produced at least six wheat crops since 1969 was greater than that of soil used for pasture or forest, while the hydraulic conductivity of soil cropped every year since 1969 was much less than that of soil under native forest. Particle size distributions for soil from the B horizons at the five management sites were found to be similar. Where pastures and crops had been established, the hydraulic conductivity of the upper B horizon was lower, and the bulk density was higher, than that of soil in the native forest (Eucalyptus spp).
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Pritchard, KE, WK Mason, and SP Byrne. "Landforming a red-brown earth dash effects of topsoil removal and redistribution on irrigated crop production." Australian Journal of Experimental Agriculture 28, no. 5 (1988): 599. http://dx.doi.org/10.1071/ea9880599.
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Landforming is the use of earthmoving machinery and laser controlled land planes to improve the efficiency of irrigation layouts. Duplex soils with shallow A horizons are vulnerable to the exposure of subsoil in this process, and production from areas where topsoil has been removed is substantially less than from normal soil. A landformed area with a large range of depths of cut (soil removed) and fill (extra soil deposited) gave a linear decrease in dry matter (DM) yield/ha of maize (Zea mays) from 23.7 to 11.2 t/ha, and of oats (Avena sativa) from 13.9 to 7.5 t/ha with increasing depths of topsoil removal, but no progressive yield increase with added soil, so that overall production was estimated to be decreased by 16%. Whole plant N concentration was 24% lower, plant Zn 33% lower and soil Zn 43% lower from areas where topsoil was removed. Ameliorating the exposed subsoil with ripping, gypsum and compensatory N and P fertiliser produced only 71% of maize DM compared with normal soil (16.5 v. 11.7 t/ha). However, the replacement of 75 mm of topsoil completely restored yield. In a pot experiment which removed many of the physical limitations of the field, maize yields from subsoil and topsoil were similar when Zn was added to the subsoil in addition to N, P and K. Although Zn deficiency can limit maize growth on exposed subsoil, soil physical characteristics are a major cause of reduced yield and these were not eliminated in the field by amelioration. The cost of topsoil replacement during landforming may be less, in the long term, than amelioration plus cumulative production losses. The importance of topsoil in maintaining the yield potential of cropping land should not be underestimated in landforming designs for irrigation.
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Fettell, NA, and HS Gill. "Long-term effects of tillage, stubble, and nitrogen management on properties of a red-brown earth." Australian Journal of Experimental Agriculture 35, no. 7 (1995): 923. http://dx.doi.org/10.1071/ea9950923.
Full textAbstract:
Differences in soil organic carbon (C), total nitrogen (N), and pH resulting from 14 and 15 years of different tillage, stubble, and fertiliser N management practices were measured for a red-brown earth at Condobolin in western New South Wales. The 5 main treatments comprised stubble burning or retention in factorial combination with cultivation and direct drilling, and stubble incorporation combined with cultivation. Two rates of N fertiliser (0 and 40 or 50 kg/ha) were applied annually, and wheat was grown each year. There were no significant differences between tillage and stubble treatments for soil organic C, total N, or pH. Fertiliser N application caused small but significant increases in organic C and total N but decreased the pH of the surface 2.5 cm of soil by 0.4-0.5 units compared with the nil fertiliser rate. The study indicates that direct drilling and stubble retention with continuous wheat have had little long-term effect on soil organic C and total N in this low rainfall environment.
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Roesner, E. A., N. A. Fettell, and J. Brockwell. "Liming and choice of pasture species improve rhizobial persistence in an acidic chromosol (red-brown earth)." Australian Journal of Experimental Agriculture 45, no. 3 (2005): 247. http://dx.doi.org/10.1071/ea03153.
Full textAbstract:
An experiment was conducted to determine the persistence of soil root-nodule bacteria as influenced by different rates of lime and the previous pasture species. The work was done at Condobolin, central-western New South Wales, on a chromosol (red-brown earth), acidic in the upper profile (pHCa 4.6), which was representative of soils for an extensive region of the eastern Australian wheat belt. In autumn 1997, the experimental area was treated with 4 rates (6.0 t/ha, 3.0 t/ha, 1.5 t/ha, nil) of finely-ground agricultural limestone and sown with 5 pasture species: lucerne (Medicago sativa), barrel medic (M. truncatula), subterranean clover (Trifolium subterraneum), rose clover (T. hirtum) and ryegrass (Lolium rigidum). The pastures were removed with herbicide and cultivation in September 2000. The land lay fallow for 9 months and then was sown to wheat (Triticum aestivum) in autumn 2001 and again in autumn 2002. The most probable numbers of soil (0–10 cm) populations of the root–nodule bacterium for Medicago species (Sinorhizobium meliloti) and for the Trifolium species (Rhizobium leguminosarum bv. trifolii) were counted in May 2001 and May 2002. Soil pH, which was significantly (P<0.05) elevated 12 months after liming, declined substantially during the next 4 years although there was no concomitant decline in the pH of unlimed soil. The pasture species were highly productive of both pasture dry matter and nitrogen. The majority of legume pasture nitrogen was a consequence of symbiotic nitrogen fixation. There was a small but significant (P<0.05) dry matter response to application of lime in lucerne and barrel medic, and a larger nitrogen response to liming in lucerne, barrel medic and rose clover. Nitrogen fixation by rose clover appeared suboptimal. It was assumed from the density of plants that large populations of rhizobia developed in the soil during the growth of the legumes. Nine months after removal of the pasture, rhizobia numbers had fallen to low levels but did not fall further during the following year. The initial fall was attributed to high soil temperatures and low soil moisture during the Condobolin summer. The population of rhizobia for Trifolium species was about twice that of the rhizobia for Medicago species but the difference was not statistically significant. Liming had an overriding influence on the size of rhizobial populations, except in plots that had previously grown ryegrass where numbers remained low irrespective of rate of liming. Overall, most probable numbers escalated with each increase in rate of liming, from 10/g soil in the nil lime plots to 708/g in the 6 t/ha lime plots. The rhizobial homology of the pasture species (i.e. Sinorhizobium meliloti for the Medicago species and Rhizobium leguminosarum bv. trifolii for the Trifolium species) had an underlying but major influence on most probable numbers and in determining which rhizobial species occurred more commonly. Estimated populations of rhizobia in soils from homologous legumes were about 8 times those found in soils from non-homologous legumes. The benefits of applying lime to this red-brown earth soil may not have been merely a consequence of correction of low soil pH; increased levels of calcium may also have had a role. The results are discussed in relation to re-establishment of legume leys after the cereal phase of the cropping system.
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Halász, Amadé, and Ákos Halmai. "The colour analysis method applied to homogeneous rocks." Geologos 21, no. 4 (December 1, 2015): 233–39. http://dx.doi.org/10.1515/logos-2015-0019.
Full textAbstract:
Abstract Computer-aided colour analysis can facilitate cyclostratigraphic studies. Here we report on a case study involving the development of a digital colour analysis method for examination of the Boda Claystone Formation which is the most suitable in Hungary for the disposal of high-level radioactive waste. Rock type colours are reddish brown or brownish red, or any shade between brown and red. The method presented here could be used to differentiate similar colours and to identify gradual transitions between these; the latter are of great importance in a cyclostratigraphic analysis of the succession. Geophysical well-logging has demonstrated the existence of characteristic cyclic units, as detected by colour and natural gamma. Based on our research, colour, natural gamma and lithology correlate well. For core Ib-4, these features reveal the presence of orderly cycles with thicknesses of roughly 0.64 to 13 metres. Once the core has been scanned, this is a time- and cost-effective method.
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GREENE, R. S. B., P. RENGASAMY, G. W. FORD, C. J. CHARTRES, and J. J. MILLAR. "The effect of sodium and calcium on physical properties and micromorphology of two red-brown earth soils." Journal of Soil Science 39, no. 4 (December 1988): 639–48. http://dx.doi.org/10.1111/j.1365-2389.1988.tb01246.x.
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Greene, R. S. B., and I. B. Wilson. "Amelioration on some physical properties and nutrient availability of an exposed B horizon of red-brown earth." Soil Use and Management 5, no. 2 (June 1989): 66–71. http://dx.doi.org/10.1111/j.1475-2743.1989.tb00763.x.
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Blaikie, S. J., J. R. Hirth, K. L. Greenwood, K. A. Olsson, K. E. Dellow, and K. B. Kelly. "Soil properties, root responses and production of irrigated pasture on a red-brown earth after subsoil modification." Australian Journal of Experimental Agriculture 42, no. 4 (2002): 453. http://dx.doi.org/10.1071/ea01076.
Full textAbstract:
Soils used for growing irrigated pasture in northern Victoria have shallow (0.10-0.15 m) topsoils and dense, clay subsoils. Reducing soil limitations to root growth and function has the potential to increase pasture production. Therefore, subsoil modification treatments, comprising loosening and fragmentation of the B horizon to depths of 0.2, 0.4 and 0.6 m, the incorporation of calcium ameliorants, superphosphate and application of organic matter to the soil surface, were compared with unmodified soils and a 0.4 m deep topsoil, in a red-brown earth over a 2-year period (1994-96). Subsoil modification improved the physical condition of the soil. Air-filled porosity of the deep-modified soils (0.4 and 0.6 m deep), 24 h after irrigation, exceeded 15% at 0.1 and 0.3 m depths in both years, and was always higher than in the unmodified soils. Penetrometer resistance was markedly lower in the deep-modified subsoils in both years. Greater earthworm activity was associated with these improved soil physical conditions. However, the soil treatments did not result in greater root length or root mass beneath the pasture. In the first year, pasture yield was greater on the deep-modified soils (25-31 t DM/ha) than on the unmodified soils (19 t DM/ha). In the second year, the yield advantage of the deep-modified treatments decreased to 11%, despite the maintenance of improved soil physical conditions. In both years, pasture yields were highest where there was an initial surface application of 20 t DM/ha organic matter to a modified soil. We conclude that structural modification of the B horizon can increase pasture yields on this soil. However, further research is necessary to maintain these yield increases beyond the initial year and to develop more practical systems of soil modification.
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Crouch, R. J. "Rates and mechanisms of discontinuous gully erosion in a red-brown earth catchment, new south wales, australia." Earth Surface Processes and Landforms 15, no. 3 (May 1990): 277–82. http://dx.doi.org/10.1002/esp.3290150309.
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Cox, JW, E. Fritsch, and RW Fitzpatrick. "Interpretation of soil features produced by ancient and modern processes in degraded landscapes. VII. Water duration." Soil Research 34, no. 6 (1996): 803. http://dx.doi.org/10.1071/sr9960803.
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Rising saline groundwater and fresh perched water have increased over 120 years (modern processes) in the Mediterranean region (>600 mm per annum) of the Mt Lofty Ranges, South Australia. This was caused by replacement of native vegetation with pastures which use less water. Relationships between morphological features (mainly soil colour) and field measurements (e.g. watertable duration, salinity, and sodicity) were studied to 3 m at 12 sites down a representative toposequence of red-yellow-grey duplex soils (Palexeralfs-Natraqualfs), which are common from crest to flat in these catchments. Three soil systems were identified from groupings of soil features: (i) brown/grey topsoil system (e.g. A and E horizons), (ii) red subsoil system (e.g. Bt), and (iii) yellow/white subsoil system (e.g. Btng or Cg). A water duration index was developed to quantify water duration in the brown/grey topsoil system from perched water levels measured in 12 dipwells installed to 0.5 m. Nested piezometers were used to determine if unsaturated zones occurred within the subsoil systems. Measured water duration and levels were compared with the presence pr absence of inferred redoximorphic features. Most features in the brown/grey topsoil system and the red and yellow/white subsoil systems reflected differences in water duration. A conceptual model was constructed to match successive changes in hydrology with differences in soil morphology and thus distinguish between modern and relict (late Mesozoic) soil features that developed under past and present hydrological conditions.
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McKenzie, DC, KW Hucker, LJ Morthorpe, and PJ Baker. "Field calibration of a neutron-gamma probe in three agriculturally important soils of the Lower Macquarie Valley." Australian Journal of Experimental Agriculture 30, no. 1 (1990): 115. http://dx.doi.org/10.1071/ea9900115.
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A neutron-gamma probe was field calibrated in a grey clay, a grey-brown clay and a red-brown earth near Trangie, New South Wales. These are the main soils used for irrigated agriculture in this region. Accurate but simple calibrations and sampling procedure\ are required by commercial irrigators and researchers. Bias in the estimation of soil water content was minimised by using separate calibrations for each soil and depth where equations were significantly different. Precision tended to be higher where an equation combining all depths and soils was used. but the introduction of large bias at some depths suggests that soil-specific equations should be used where possible. Calibration error generally was a smaller component of total error than location error, particularly where the combination equation was used. The errors associated with commercial sampling methods are discussed. The relationship between gamma count rate ratio and soil wet bulk density was poor, particularly in the grey and grey-brown clays, and this technique was considered to be inadequate for the measurement of bulk density in the field.
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Kelly, KB. "Effects of soil modification and treading on pasture growth and physical properties of an irrigated red-brown earth." Australian Journal of Agricultural Research 36, no. 6 (1985): 799. http://dx.doi.org/10.1071/ar9850799.
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Lemnos loam, a red-brown earth used extensively for pasture production in northern Victoria, and its exposed subsoil (topsoil removed) were both subjected to surface cultivation and total profile modification. Total profile modification consisted of excavating and mixing the top 1.1 m of soil and incorporating gypsum (10 t ha-1), superphosphate (4.5 t ha-1) and ammonium nitrate (0.5 t ha-1) . A white clover-perennial ryegrass pasture was established. Treading by cattle was superimposed over these soil treatments. Exposure of the subsoil, as often occurs with laser landforming, reduced pasture growth by 30% compared with a normal soil profile. Modification of the exposed subsoil negated this effect. Modification of the normal soil profile had little effect on pasture production but did influence pasture composition. Treading had a cumulative effect with time, reducing pasture production by 6, 9 and 12% in 1981, 1982 and 1983, respectively. This occurred despite the precaution of allowing grazing only when the soil was dry. Profile modification resulted in increased pore space and root growth, and lowered bulk density and penetrometer resistance at depth. Treading increased surface soil bulk density, with penetrometer studies showing that this effect was confined to the top 0.15 m.
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Kay, BD, and AR Dexter. "The influence of dispersible clay and wetting/drying cycles on the tensile strength of a red-brown earth." Soil Research 30, no. 3 (1992): 297. http://dx.doi.org/10.1071/sr9920297.
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The tensile strength of aggregates is a dynamic property under field conditions and for any given soil reflects the integration of processes leading to a strengthening and weakening of failure zones. The objectives of this study were to determine if variation in the tensile strength of natural aggregates from a red-brown earth could be related to the combined effects of (a) conditions favouring dispersion of clay and a subsequent increase in strength by cementation on drying and (b) wetting/drying cycles which would result in a decrease in strength. Aggregates were collected from the A horizon of different long-term rotations. The seasonal variation in tensile strength was assessed using data collected in 1988 and unpublished data which had been collected annually between 1978 and 1981. Trends in tensile strength over 5 years confirmed the importance of an interaction between climatic conditions which could lead to increased dispersion of clay and wetting/drying cycles. The extent of weakening of failure zones by wetting/drying cycles varied with the rotation. The nature of the impact of cropping history on tensile strength was dependent on antecedent climatic conditions.
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Cai, L., SA Prathapar, and HG Beecher. "Modelling leaching and recharge in a bare transitional red-brown earth ponded with low salinity water in summer." Australian Journal of Experimental Agriculture 34, no. 7 (1994): 1085. http://dx.doi.org/10.1071/ea9941085.
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A modelling study was conducted to evaluate water and salt movement within a transitional red-brown earth with saline B horizon soil when such waters are used for ponding in summer. The model was calibrated using previously published experimental data. The calibrated model was used to evaluate the effect of depth to watertable, saturated hydraulic conductivity, and ponding water salinity on infiltration, water and salt movement within the soil profile, and recharge. The study showed that when initial soil water content and the saturated hydraulic conductivity (Ks) are low, infiltrating water will be stored within the soil profile even in the absence of a shallow watertable. Once the soil water content is high, however, recharge will be significant in winter, even if there is no net infiltration at the soil surface. Infiltration rates depend more on Ks than the depth to watertable if it is at, or below, 1.5 m from the soil surface. When Ks is high, recharge under ponding will be higher than that under winter fallow. Subsequent ponding in summer and fallow in winter tend to leach salts from the soil profile, the leaching rate dependent on Ks. During winter fallow, due to net evaporation, salts tend to move upwards and concentrate near the soil surface. In the presence of shallow watertables, leached salts tend to concentrate at, or near, the watertable.
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Smith, C. J., and O. A. Gyles. "Fertilizer and soil nitrogen accumulation by irrigated barley grown on a red-brown earth in south-eastern Australia." Plant and Soil 119, no. 1 (September 1989): 155–61. http://dx.doi.org/10.1007/bf02370280.
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Oades, JM, AM Vassallo, AG Waters, and MA Wilson. "Characterization of organic matter in particle size and density fractions from a red-brown earth by solid state 13C NMR." Soil Research 25, no. 1 (1987): 71. http://dx.doi.org/10.1071/sr9870071.
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Size and density fractions separated from a red-brown earth have been analysed by high-resolution solidstate 13C nuclear magnetic resonance (n.m.r.) spectroscopy. Resonances from O-alkyl carbon (mainly carbohydrate) predominated in the spectra of the largest (250-2000 �m) fractions, whereas alkyl carbon resonances (mainly polymethylene) predominated in the spectra of clay fractions. Paramagnetics, mainly Fe3+, were found to influence the amount and type of carbon seen in 13C solid-state n.m.r. spectra of clay fractions containing more than several per cent iron oxides. Removal of iron oxides by reduction with dithionite allowed aromatics, carboxyls and carbohydrates to be detected by 13C n.m.r.
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Zaitseva, N. A., I. I. Klimova, E. V. Yachmeneva, and A. S. Dyakov. "The study of onion source material in the light-brown soils of the Caspian Sea arid zone." Agricultural Science Euro-North-East 22, no. 6 (December 13, 2021): 857–64. http://dx.doi.org/10.30766/2072-9081.2021.22.6.857-864.
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In the conditions of the Astrakhan region there have been studied onion accessions of various ecological and geographical origin from the world collection of the Federal Research Center N. I. Vavilov All-Russian Institute of Plant Genetic Resources. The aim was to search and isolate sources and donors of agronomic traits for breeding work. Over three years of study (2017-2019), 117 onion samples were evaluated, of which 14 most promising accessions were identified based on the results of phenological, morphological and biometric observations and counts. The most productive samples with the yield from 52.3 to 64.1 t/ha in the conditions of the light-brown soils from Australia (Selfed), Hungary (Zillani), USA (Red Mom), Canada (Nothern) have been selected. Of these, the most adaptive to the conditions of the arid zone are Nothern, Selfed, Zillani, Red Mom (adaptability coefficient 1.19...1.46). According to the index form (1.0), the following specimens were identified: Vertus (Denmark), Southport (Canada), Zillani (Hungary), Jetset (Netherlands), Encore (USA), Kyrmyz (Abkhazia). Varieties with the complex of agronomictraits are the most valuable source material for onion breeding in the arid zone of light-brown soils of the Astrakhan region: Selfed (Australia), Zillani (Hungary), Red Mom (USA), Nothern (Canada).
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Latirah, Latirah, Lisawati Tanzil, Desiant Hartanti, and Priyanto Dwi Nugroho. "Formulation of Semi Solid Lip Dying From Extract Areca Seeds (Areca Catechu L.) With Several Concentrations." SANITAS: Jurnal Teknologi dan Seni Kesehatan 13, no. 1 (June 21, 2022): 13–20. http://dx.doi.org/10.36525/sanitas.2022.2.
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Areca nut (Areca catechu L.) is a natural dye as a substitute for synthetic dyes which are less safe for skin health. This study aims to make a semi-solid form of lip color cosmetic preparations with several concentrations. Extracts was made by soaking the powder using 96% ethanol.The results of this reseach is that the lip color has a vanilla smell, soft and homogeneous texture, visually brown color, pH 6.00 to 6.50. Melting point between 41 – 440C Color release test or smear test for a 40% concentration formula shows a good and homogeneous color. Chemical test results using a chromameter formula 20% 0HUE 34.87 (red), 30% 23.10 (red) and 40% 15.03 (purple red)
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Summers, Natalie, Geir Johnsen, Aksel Mogstad, Håvard Løvås, Glaucia Fragoso, and Jørgen Berge. "Underwater Hyperspectral Imaging of Arctic Macroalgal Habitats during the Polar Night Using a Novel Mini-ROV-UHI Portable System." Remote Sensing 14, no. 6 (March 9, 2022): 1325. http://dx.doi.org/10.3390/rs14061325.
Full textAbstract:
We describe an Underwater Hyperspectral Imager (UHI) deployed on an instrument-carrying platform consisting of two interconnected mini-ROVs (Remotely Operated Vehicle) for the mapping and monitoring of Arctic macroalgal habitats in Kongsfjorden (Svalbard) during the Polar Night. The mini-ROV-UHI system is easy to transport, assemble and deploy from shore, even under the dark, icy and cold conditions of the Arctic Polar Night. The system can be operated by two persons, keeping the operational costs low. In vivo hyperspectral reflectance of collected specimens of brown, red and green macroalgae was measured with a spectrometer in the lab to provide a spectral library for supervised pigment group classification based on UHI photomosaics. The in situ UHI-photomosaics provided detailed information of the areal coverage of the seafloor substrate (16%), as well as brown (51% habitat cover), red (18%), and green (14%) macroalgae, with spatial resolution in the range of cm and spectral resolution of 2 nm. The collected specimens from the mapped area were also used for species identification and health state evaluation. This innovative UHI sampling method provides significant information about macroalgal distribution and physiology, and due to its flexibility in terms of deployment, it is applicable to a variety of environments.
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Feng, Jin-Liang, Jian-Ting Ju, Feng Chen, Zhao-Guo Hu, Xiang Zhao, and Shao-Peng Gao. "Identification of a late Quaternary alluvial–aeolian sedimentary sequence in the Sichuan Basin, China." Quaternary Research 85, no. 2 (March 2016): 279–89. http://dx.doi.org/10.1016/j.yqres.2016.01.006.
Full textAbstract:
The late Quaternary sedimentary sequence in the northwestern part of the Sichuan Basin consists of five lithological units and with increasing depth include the: Chengdu Clay; Brown Clay; Red Clay; Sandy Silt; and basal Muddy Gravel. The genesis, provenance and age of the sediments, as well as the possible presence of hiatuses within this sequence are debated. Measurements of grain-size, magnetic susceptibility, quartz content, quartz δ18O values, element composition, and Sr–Nd isotopic concentrations of samples from a typical sedimentary sequence in the area provides new insights into the genesis and history of the sequence. The new data confirm that the sediments in study site are alluvial–aeolian in origin, with basal alluvial deposits overlain by aeolian deposits. Like the uppermost Chengdu Clay, the underlying Brown Clay and Red Clay are aeolian in origin. In contrast, the Silty Sand, like the basal Muddy Gravel, is an alluvial deposit and not an aeolian deposit as previously thought. Moreover, the succession of the aeolian deposits very likely contains two significant sedimentary hiatuses. Sedimentological analysis demonstrates that the source materials for the aeolian deposits in the northwestern part of the Sichuan Basin and those on the eastern Tibetan Plateau are different. Furthermore, the loess deposits on the eastern Tibetan Plateau are derived from heterogeneous local sources.
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Ross, Ian L., Younes Alami, Paul R. Harvey, Wafa Achouak, and Maarten H. Ryder. "Genetic Diversity and Biological Control Activity of Novel Species of Closely Related Pseudomonads Isolated from Wheat Field Soils in South Australia." Applied and Environmental Microbiology 66, no. 4 (April 1, 2000): 1609–16. http://dx.doi.org/10.1128/aem.66.4.1609-1616.2000.
Full textAbstract:
ABSTRACT Rhizobacteria closely related to two recently described species of pseudomonads, Pseudomonas brassicacearum andPseudomonas thivervalensis, were isolated from two geographically distinct wheat field soils in South Australia. Isolation was undertaken by either selective plating or immunotrapping utilizing a polyclonal antibody raised against P. brassicacearum. A subset of 42 isolates were characterized by amplified 16S ribosomal DNA restriction analysis (ARDRA), BIOLOG analysis, and gas chromatography-fatty acid methyl ester (GC-FAME) analysis and separated into closely related phenetic groups. More than 75% of isolates tested by ARDRA were found to have >95% similarity to either Pseudomonas corrugata or P. brassicacearum-P. thivervalensis type strains, and all isolates had >90% similarity to either type strain. BIOLOG and GC-FAME clustering showed a >70% match to ARDRA profiles. Strains representing different ARDRA groups were tested in two soil types for biological control activity against the soilborne plant pathogen Gaeumannomyces graminis var. tritici, the causative agent of take-all of wheat and barley. Three isolates out of 11 significantly reduced take-all-induced root lesions on wheat plants grown in a red-brown earth soil. Only one strain, K208, was consistent in reducing disease symptoms in both the acidic red-brown earth and a calcareous sandy loam. Results from this study indicate that P. brassicacearum and P. thivervalensis are present in Australian soils and that a level of genetic diversity exists within these two novel species but that this diversity does not appear to be related to geographic distribution. The result of the glasshouse pot trial suggests that some isolates of these species may have potential as biological control agents for plant disease.