保水剂特性测定及其在农业中的应用

Characteristics of Aquasorb and Its Application in Crop Production

高分子化学材料的保水剂 ,具有高倍吸水和保水能力 ,种类较多。该研究测定了钠类保水剂主要化学特性改土保土效应。通过田间试验 ,分析其对作物产量和肥料利用率的影响。研究表明 ,保水剂溶液钠离子和电导度随其浓度增加而增加 ,但增幅较小 ,对 p H值影响不大。钙、镁等二价离子对聚丙稀酸钠保水剂的吸水力拮抗作用明显 ,与尿素混用无不良效果。土壤加入保水剂后 ,其保水能力增加 ,改善结构 ,沙壤土较重壤土更显著。当土壤中保水剂含量在 0 .0 0 5 %～ 0 .0 1%范围时 ,土壤团聚体增加量明显。在 - 0 .5 MPa土壤水势压内 ,含保水剂 0 .5 %的土壤中 90 %水分可为植物根系利用。研究认为 ,保水剂保水作用主要表现 4方面 :自身保水、改良土壤结构增加土壤保水、促进植物生长提高肥料利用率、缓慢释水减少蒸发。田间试验发现 ,穴施 15 kg/hm2的保水剂的玉米和马铃薯分别增产 2 2 %和 16 % ,投产比为 1∶ 3.5和 1∶ 4 .2。保水剂与尿素或尿素磷肥混合使用于玉米 ,可分别提高尿素和磷肥利用效率 18.72 %和 2 7.0 6 %。

Aquasorb is a kind of sodium polymer with characteristic of absorbing and storing water. There are many types and varieties in commercial market. The purpose of this study is to determine the chemical features of sodium polymer and its effect on soil improving, and to analyze the influence on crop yield and fertilizer use efficiency in farming field. The result showed that and electronic conductivity (EC) were increased but not so high when the concentration of sodium polymer was raised. pH value was almost not affected. Ions with two positive charges, such as [Ca 2+ ] and [Mg 2+ ] have a negative impact on drinking water characteristic of sodium polymer markedly, which is stronger than that of one positive or negative charge, such as Na + and H 2PO - 4. It does not influence the drinking water of sodium polymer for different concentrations of urea. When soil is added with sodium polymer, the water holding capacity is raised, the aggregate of the soil is increased, this feature on sandy soil is more remarkable than that on clay soil, especially when there is 0.005% to 0.01% sodium polymer in soil. The test indicated that over 90% water holding by the sodium polymer can be used by plant. Based on the current results, it can be concluded that there are four aspects for action of sodium polymer, (1)conserving water by itself, (2)raising water holding by improving soil structure, (3)enhancing growth of plant and raising fertilizer use efficiency, (4)and reducing soil evaporation. The field test result showed that using sodium polymer by hole method at 15 kg/hm 2, the yields of corn and potato were increased by 22% and 16%, and the ratios of investment to benefit were 1∶3.5 and 1∶4.2, respectively. When sodium polymer was mixed with urea or with urea and phosphorus fertilizer, the urea and phosphorus fertilizer use efficiencies were increased by 18.7% and 27.1%, respectively.