Organic Conditioners Research Articles

Soil and plant analysis as a guide for interpretation of the improvement efficiency of organic conditioners added to different soils in Egypt

Four local organic conditioners:biogas residues (precipitates), poultry manure, sewage sludge and composted town refuse were subjected to an experiment aimed at evaluation their efficiency for improvement the physical and chemical properties of four soils that known at El‐Fayoum area as soils below the production levels. The tested soils were alluvial clay from the Faculty Farm at Dar El‐Ramad, highly calcareous loamy sand from the Faculty Farm at Demo, calcareous sandy loam from Kom Osheem village and heavy clay from Kassr Rashwan village. With each of the tested soils, treatments comprised each of the above mentioned organic conditioners at increasingly levels depending on its carbon/nitrogen (C/N) ratio were performed. Then, the treatments were subjected to a pot experiment cropped with wheat plants under greenhouse conditions. With each treatment, determinations of the soil physical properties (saturation percentage, field capacity, bulk density, total porosity, and hydraulic conductivity) and the soil chemical properties [pH, EC, organic matter, total nitrogen (N) and available N, phosphorus (P), and potassium (K)] were conducted before and after cultivation. At the cropping, dry matter and grain yield were weighted and some parameters of the plants were recorded. Concurrently, determinations of total N, P, and K were conducted in samples of root, vegetative growth, and grains at the cropping. The obtained results were statistically analyzed and graphically presented to indicate and recommend the optimum improvement effect within the used organic conditioners with each of the tested soils. The tested organic conditioners were evaluated for application under the local conditions.

Synergistic effects of elemental sulfur and synthetic organic conditioner amendments on selected chemical properties of calcareous soils

This study evaluated the combined effects of elemental sulfur (ES) and synthetic organic conditioner (SOC) amendments on the chemical properties of calcareous soils from arid and semiarid regions. A 60‐day laboratory incubation experiment was conducted to determine if amending ES‐treated soils with SOCs would improve selected chemical properties such as pH and soluble and extractable nutrients. Four calcareous soils from central Saudi Arabia varying in CaCO3 content were used. Air‐dried soil samples were treated with (1) ES at rates of 7.7,14.8, 23.7, and 19.0 g kg−1 to neutralize 50% CaCO3 content of soil 1, soil 2, soil 3, and soil 4, respectively; (2) four SOCs— Broadleaf(BL), Aquasorb (AS), Agrihope (AH), and Hydrogel (HG)‐at a rate of 02% (dry weight basis). The addition of ES or ES + individual SOC amendments improved some of the soil chemical properties. In all cases, addition of ES + SOC was more effective than ES alone as determined by a decrease in soil pH and an increase in soluble SO4 2‐ and Na+, as well as extractable Fe and Mn. Addition of ES alone was more effective than ES + SOC only in increasing soluble Ca2+ and Mg2+. In contrast, the addition of an individual SOC adversely affected soil properties, resulting in an increase in soil pH and soluble Na+ and decreases in soluble Ca2+ and Mg2+ and extractable Zn, Fe, and Mn. Extractable Cu and P were not affected by the changes in soils chemistry induced by the treatments. Soluble K concentrations were significantly high in all soil samples treated with the HG conditioner and ES + HG. The deleterious effects by individual SOC on selected soil chemical properties indicates the potential adverse effect by these conditioners on calcareous soils. Nevertheless, the addition of ES in conjunction with SOC was generally synergistic and improved soil properties.

Soil microaggregation as influenced by uncharged organic conditioners

Abstract To assess the interaction of water soluble stabilizing agents with soil particles, soil microaggregation was studied after treatments with two uncharged organic conditioners, Polyvinyl alcohols (PVAs) and Dextrans, of different molecular weight. The size distribution of microaggregates (diameter 75 μm aggregates. The extent of this modification increased with the molecular weight of the conditioners and, for the same molecular weight, decreased with increasing amount of conditioner used. The aggregating effect of PVAs was stronger on particles smaller then 5 μm, which formed microaggregates in the range 10–100 μm which were not broken down even by ultrasonication. S.E.M. micrographs of soil aggregates confirmed the results reported above. PVAs and Dextrans appeared to produce a...

Sludge Treatment and Disposal Techniques for Operation of the Coleshill Sludge Destruction Plant, U.K.

The Coleshill Sludge Destruction Plant has to process 1100 m3/d of wet sludge to achieve an inert ash occupying 18-20m3. Output is expected to increase dramatically with the closure of small, less effective works and increasing use of sewer transport as a means of exporting sludges to large treatment centres. The greatest progress at this large pressing-incineration unit is a better understanding of the nature and variation of the feed sludge. Sophisticated monitoring techniques and the judicious blending of both organic and inorganic chemical conditioners has led to the best plant performance to date. Overall performance and economic studies are leading to increased use of microprocessor control and computer technology.