Effects of hydroxy-aluminum on flocculation and permeability of silt and clay fractions separated from paddy soils

Flocculation tests and permeability measurements were carried out for silt and clay fractions separated from surface and subsurface horizons of four paddy soils. There was not much difference in the flocculating power between A1(OH)_2.2C1_0.8 and CaSO₄. Their flocculation value, 0.3 to 3 mM, was attained by adding the reagents at the rate of 0.24 to 2.4 mmol/100 g of the silt and clay. The flocculation with A1(OH)_2.2C1_0.8 or CaSO₄ did not affect the sediment volume of the silt and clay. This sediment volume was smaller for the surface than for the subsurface horizons of each soil, suggesting that soil organic matter and repetition of wetting and drying contribute to the stable aggregation of the silt and clay in the surface horizon. The permeability was higher for the silt and clay fractions separated from the surface horizon than that from the subsurface horizon, and the addition of 2.5 to 4.2 mmol of A1(OH)_2.2C1_0.8 or CaSO₄/100g of the silt and clay increased its permeability by 1.5 to 4 times. The effect of A1(OH)_2.2C1_0.8 was more lasting than that of CaSO₄ and was recognized even after 200 ml of water passed through 1 g of the silt and clay. The effect of the flocculating reagent on the permeability was more or less enhanced by air-drying the treated silt and clay.     

Adsorption of alkali chloride and ammonium halide on halloysite

It is generally accepted that broken bonds are the major cause of cation exchange in kaolin minerals, although the studies of a “fireclay” type of kaolin mineral (8) and hydrated halloysite (12, 15) seem to indicate that lattice substitutions, such as that found for 2 : 1 type of clay minerals, account for the fairly large parts of the cation-exchange capacities of some kaolin clays, particularly with poor crystallinity.     

Characterization of zinc adsorption sites in two mineral soils

The adsorption of Zn, as compared with Mg, on two mineral soils, which differed in their major cation-exchange materials and with and without Ca-saturation, was measured in the presence of free CaCl₂.

The adsorption of Zn as well as Mg occurred on cation-exchange sites. The Zn adsorption data conformed to a two-term Langmuir equation. The presence of two kinds of adsorption sites and their numbers and bonding energies were deduced. However, the Langmuir approach was not adopted on the basis of comparison between the total number of the adsorption sites for Zn deduced and the CEC of the soils.

As an alternative approach, the selectivity coefficient as defined by the equation:

was calculated for each adsorption equilibrium and plotted against the amount of Zn adsorbed. This [Zn]_soil plot was used to estimate the capacities of the soil to adsorb Zn with specified affinities. The value varied between 1 and 1,000, whereas the corresponding value varied only between 0.5 and 1. The value was dependent upon the amount of Zn adsorbed, the status of exchangeable cations, and the major cation-exchange materials (montmorillonite VS. allophane-imogolite) in the soils. The importance of surface OH groups in allophane-imogolite as specific adsorption sites for Zn was suggested.     

Formation and properties of hydroxy iron(iii) oligomer-citrate complex

Instantaneous neutralization of Fe (III) chloride dissolved in N a citrate by powdery NaHC03 gave stable clear brown sols. The sol particles separated by dialysis and freeze-drying showed a single diffraction peak at 2 nm and a citrate/Fe molar ratio of about 0.2 irrespective of the composition of the starting solutions. This indicates that the product may be a novel phase of Fe (III) citrate.     

Interaction Effect of Water Magnetization and Water Salinity on Yield,Water Productivity and Morpho-Physiological of Balkız Bean (Phaseolus vulgaris)

Developing new tools for using low-quality irrigation waters is vital for the sustainability of irrigated agriculture and minimizing salt accumulation. Therefore, the present study focused on the interactive influence of irrigation treatments (magnetized (MT) and non-magnetized (NMT)) and water salinities (0.38, 1.5, 4.5, and 7.0?dSm^?1) on soil salinity, water use efficiency, yield and morpho-physiological changes of Balk?z bean. A pot experiment was conducted in a randomized complete block design with three replications under the rain shelter condition. Irrigation water MT treatment increased fresh bean yield, water use efficiency (WUE) and irrigation water use efficiency (IWUE) by 21.35, 23.00 and 14.8%, respectively, while saturated soil salinity was reduced by 20%, compared to NMT treatments. The leaf area, stomata, and leaf succulence in green beans in the MT treatment significantly increased by 13.4, 23.9, and 3.3% compared with those in the NMT treatment. Stems of the bean crops were more sensitive to salinity stress followed by roots and leaves. The study revealed that irrigation with magnetically treated water manages salinity related yield loss through increased morphological features as well as osmotic and stomatal adjustments. In addition, the bean crops showed an ability to protect water in tissue against salinity toxicity up to 5.24?dSm^?1 soil salinity level under magnetized saline water conditions. Finally, irrigation with magnetically treated 0.38?dSm^?1 irrigation water can be recommended due to providing a higher yield, WUE, IWUE, and sustainable production under saline irrigation in water scarcity regions.

     

ELEMENTAL COMPOSITION OF PEPPER PLANTS FERTILIZED WITH PELLETIZED POULTRY MANURE

Poultry manure (PM) has been traditionally applied to crops for decades as an organic fertilizer, because it is a good and balanced source of plant nutrients. Its effect on plant growth and yield has been widely investigated and is well known. However, there has been little effort to relate elemental compositions of the manure applied to their concentrations in the plants. The objective of this study was to examine the effects of PM on the growth, and essential and non-essential element composition of pepper (Capsicum annuum) leaves and also fruits. Pepper plants were grown in soil with 0, 10, 20, and 40 g kg^?1 PM under greenhouse conditions. Concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), silicon (Si), aluminum (Al), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), molybdenum (Mo), chloride (Cl), nickel (Ni), bromine (Br), rubidium (Rb), strontium (Sr), barium (Ba), lanthanum (La), and cerium (Ce) in leaves at the flowering stage and in fruits were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Poultry manure fertilization significantly improved pepper shoot growth and also fruit yield, and increased leaf and fruit P concentrations but not N, K, Mg, Si, Al, Ni, and Fe. Leaf Ca was significantly reduced by increased rate of PM application. Applied PM increased the concentrations of leaf and fruit Zn and Cl. Poultry manure applications had a positive effect on the concentrations of leaf Cu, and fruit Mn. The concentrations of Rb and Ce in fruits and Br in fruit and leaves were increased by PM treatments. Applied PM levels had no clear effect on the concentrations of Ba and La in pepper leaves. The leaf Ba was the highest with 10 g kg^?1 PM, and leaf La was higher in 20 and 40 g kg^?1 PM treatments than in the control.     

Production of Carotenoids and Phospholipids by Thraustochytrium sp. in Batch and Repeated-Batch Culture

The carotenogenic thraustochytrid Thraustochytrium sp. RT2316-16 was grown in batch and repeated-batch cultures using different feeds containing glucose, or glycerol, and yeast extract, for the production of lipids, phospholipids and carotenoids. RT2316-16 produced canthaxanthin, astaxanthin and β-carotene. The effects of biotin, ascorbic acid, light and temperature were evaluated in some of the experiments. In 2-day-old batch cultures, the combined mass percentage of eicosapentaenoic acid and docosahexaenoic acid in total lipids was between 16.5% (glycerol-based medium in the dark; biomass concentration = 4.2 ± 1.1 g L⁻¹) and 42.6% (glucose-based medium under light; biomass concentration = 3.3 ± 0.1 g L⁻¹), decreasing to 3.8% and 6.1%, respectively, after day 4. In repeated-batch cultures, the total lipids in the biomass increased after glucose or glycerol was fed alone, whereas the total carotenoids (168 ± 7 μg g⁻¹ dry weight (DW)) and phospholipids in the biomass increased after feeding with yeast extract. The biomass with the highest content of phospholipids (28.7 ± 4.3 mg g⁻¹ DW) was obtained using a feed medium formulated with glycerol, yeast extract and ascorbic acid. Glycerol was the best carbon source for the production of a biomass enriched with total lipids (467 ± 45 mg g⁻¹ DW). The composition of carotenoids depended strongly on the composition of the feed. Repeated-batch cultures fed with yeast extract contained canthaxanthin as the main carotenoid, whereas in the cultures fed only with glucose, the biomass contained mainly β-carotene.     

Comparative slaughter performance and carcass quality of three Ethiopian fat-tailed hair sheep breeds supplemented with two levels of concentrate

Tropical Animal Health and Production - A study was conducted to compare carcass and noncarcass yield, carcass composition, conformation, and fat depot partitioning of three Ethiopian fat-tailed...     

Effects of vitamin and mineral premix withdrawal from diets on carcass and meat quality of feedlot steers

Tropical Animal Health and Production - The primary objective of the present study was to assess the effects of vitamin and mineral premix (VMP) withdrawal from the diets 30 and 60 days...