عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Commercial producers of polymers claim that their polymer materials hold plentiful of water using low suction so that plants are able to have access to it. If this is true, then polymers could be used to increase desired physical characteristics of sandy soils in areas with dry climatic conditions. Based on this view and using a pressure apparatus, water retention curves were evaluated for a sample of agricultural silty clay soil, a sample of blown sand, and samples of the same blown sand mixed with three different amounts of polymer. The results showed that when a mixture of sand and a kind of polymer named " Super ab 200A" was provided in a way that 0.2 to 1.0 percent (% w/w) of the mixture is polymer, the condition of water in the mixture would be similar to a clay soil. When the amount of polymer reaches to 1%, the condition would be tougher than the previous one. In other words, although polymers cause more absorption of water in sand blown sand, the stored water is kept in the soil by a suction that is higher the suction in clay. Therefore, to increase the capacity of Plant-available water in blown sands to elongate irrigation interval of planted seedlings for afforestation in dry areas, adding polymer to blown sands would result in undesirable conditions. Furthermore, using polymers increase the cost of operation. They are unsustainable materials and they may have some other disadvantages. Results of this experiment suggests that usage of clay, instead of polymer, to blown sands would create a better conditions.