الفهرس 
MATERIALS AND METHODSOnly 14 pages are availabe for public view
Abstract
SUMMARY
Laboratory and field experiments were carried out to clarify the impact of different types of natural and synthetic polymers on some hydrophysical properties (soil hydraulic parameters) of a sandy soil beside potatoes characters and yield. Because of the great importance of hydraulic polymers, a group of natural, industrial and synthetic polymers have been used and synthesized, where a polymer that has all the properties of sponge (hydrophobic) or superabsorbent polymers has been manufactured using some natural materials such as wastes from corn and wheat factories and screening stations, where these raw materials containing polymers were used. Cellulose, proteinuria, and lipid chains in the reconstruction of a type of semi-polar polymer, and this polymer was named (MUSA1). Adding 0.5% (w/w) of each treatment to soil significantly increased water retention at saturation, field capacity, total available water, and readily available water. This treatment decreased the value of the inflection point on the water retention curve as a result of enhancing water behavior in the soil. The obtained results revealed that soil water storage significantly increased from 0.271 in the control treatment (without adding polymer) up to 0.414 in treatment [T10] (Acrylic acid + Xanthan) while, field capacity significantly increased from 0.078 in control up to 0.242 for the abovementioned treatment(T10). Regarding the effects of polymer application in total available water and readily available water, data revealed significant increases in the above-mentioned parameters. Total available water increased from 0.044 in control treatment up to 0.153 in T10 and readily available water increased from 0.057 in control treatment up to 0.185 in T10.
Concerning the values of the inflection point on the soil water retention curve, the obtained results revealed that the inflection point of the control treatment (1000 mbar) decreased to 590 mbar, as a result of adding a mixture of polymer of acrylic acid + xanthan (T10). Soil depletion rate decreased due to polymer application by 25% up to 75% depending on the type of polymer and whether it was added individually or in combination with another polymer. This effect led to significant differences among control treatment (control) and the other treatments. Generally, there were significant effects of all polymers on the concerned hydrophysical properties of the studied sandy soil, i.e. storage capacity of soil water, depletion rate of soil water, soil field capacity, soil available water, readily available water, an inflection point on the soil water retention curve. Acrylic acid recorded the best results concerning soil water behavior if it was added individually to the sandy soil (Treatment 2) or in combination with Xanthan (Treatment 10) or with Lignosulphonate (Treatment 11).
Concerning the extent to which the potato crop is affected by the addition of polymers (the subject of the study), the crop is strategic, depending mainly on the availability of water and energy. In terms of dry matter yield, or what is known as biomass, the yield was not adversely affected by the use of all polymers under study. On the contrary, it was noticed from the obtained yield results, whether from the weight of the plant tubers, the dry weight of the plant, the weight of the root system, and the protein ratio, that there was a marked improvement. In all these properties, according to the yield results obtained, and also as a result of the addition of polymers, the moisture tightness of the water in the soil decreases, thus improving the activity of dehydrogenase in the soil. That is, as a result of adding polymers to the soil, the amount of water stored in it increased, and consequently, the moisture tension in the water in the soil decreased and the activity of the enzyme dehydrogenase in the soil increased.
For synthetic polymer (MUSA 1) by study it was found that besides the economic part in providing water at the level of the number of cubic meters in each irrigation, in addition to reducing the number of irrigation in half, through a study it provides nearly 100% of the required water needs in addition to this polymer, the industrial costs of it are very low, as the total industrial cost per ton It does not exceed 4000 pounds compared to standard polymers from 65000 to 7000 pounds per ton of the total industrial cost of it.