الفهرس 
EFFECT OF AMENDMENTS APPLICATION ON WATER AND NUTRIENTS MOVEMENT IN SOILOnly 14 pages are availabe for public view
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Abstract
Preservation of water and soil is a vital. Soil with weak structure is easily disrupted and carried away by the shearing action of running water. One of the highly effective solutions to this problem is to improve soil structure by adding Amendments, which are an array of synthetic and naturally derived polymers that improve soil cohesion.
Soil Amendments improves the soil’s physical qualities, especially its ability to provide nutrients to the plants.
A wide assortment of materials has been described as soil Amendments because of their ability to enhance soil quality. Some of them is organic amendments and others are inorganic amendments. Examples of organic amendments are biochar, bone meal, straw, peat, sphagnum moss, blood meal, coffee grounds, compost, tea, coir, and manure, inorganic amendments as vermiculite, sulfur, lime, and hydro-absorbent polymers.
There are many factors should be considered before choosing the suitable amendment for soil, there are at least four factors to consider in selecting a soil amendment, how long the amendment will last in the soil, soil texture, soil salinity and plant sensitivities to salts, and salt content and pH of the amendment.
The aims of our study were to
1- Quantify the effects of soil amendments on soil physical properties
2- Study the movement of water and nutrient (chloride and potassium) in soil columns under saturated condition in soil columns.
3- Modeling the movement of water pattern and nutrient distribution under with soil amendments application
To achieve these objectives a laboratory soil column experiments conducted to investigate the effect of different types of amendments on the vertical movement of water and nutrient in soil under saturated conditions.
Amendments that used in this study were banana peel, polymer and chitosan. Banana peel amendment was prepared by air drying of banana peel till reaching black color then grinded, finally passed through 2 mm sieve.
Chitosan is bought from ROTH Company. Chitosan powder which used is low molecular weight, from crab shells, chemical structure is Poly-(1.4-B-D-glucopyranosamine); 2-Amino-2-deoxy-(1-˃4)-B-D-glucopyranan.
Polymer was cross-linked sodium polyacrylate, known as Acryhope (Nippon Shokubai Company, japan), it is dry grain (0.2-1 mm)
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The treatments which used in this study were six mixtures plus control as followed
Control: soil without amendment
1% banana peel (by weight) mixed with soil (bp 1%)
2% banana peel (by weight) mixed with soil (bp 2%)
1% chitosan (by weight) mixed with soil (ch 1%)
2% chitosan (by weight) mixed with soil (ch 2%)
0.1% polymer (by weight) mixed with soil (poly 0.1%)
0.2% polymer (by weight) mixed with soil (poly 0.2%)
Soil column was packed by adding a thin layer of coarse quartz, then addition of discrete soil portions into the column The soil portions were thus deposit in small volume (commonly in the order of a few cm). Lightly scarifying the soil surface after compaction and before addition of another soil portion, gentle column vibration was simultaneous be applied to help soil being more uniformly deposit. This procedure is repeated several times until the column is filled. To avoid splashing of the soil material during the irrigation process another thin layer of coarse quartz sand was placed above the surface of soil
The aimed bulk density were approximately 1.7 gm/cm3 for all mixed and control columns used in this work, a slight change occurred in some columns after the initial condition due to change in soil column length due to water flow inside the column (i.e., upward saturation, followed by downward flow with 0.01 M CaCl2) which resulted in recalculation of the bulk density.
The soil columns were slowly saturated from the bottom with distilled water. After saturating the soil columns, a steady downward flow of distilled water with a constant head was applied to leach the soil column. The leaching process continued until the leachate EC reaches 0.13 ds/m. A solution of CaCl2 (0.01 N) + K2SO4 (100 ppm k) was then applied to soil column until the relative concentration (C/Co) reach unity for chloride and potassium.
where C is the solute concentration which leached with time also called absolute concentration, Co the concentration of applied solute. The leachate samples were collected at different time and analyze for concentrations of CL and K. Sampling time and its volume was being recorded to plot the results in the form of relative concentration of the effluent C/Co versus time and the number of displaced pore volumes to draw breakthrough curves(BTCs(
Two computer models; the CXTFIT model and Solute transport model were used to simulate or fit the observed data.