塇土大颗粒保水剂的吸水、释水及保水保肥特性研究

Characteristics of Large Granule Water Retaining Agent in Absorption,Release and Retention of Water and Fertility

以塇土大颗粒保水剂为材料,研究其吸水、重复吸水与释水性能,同时利用淋溶试验模拟其对椰子园土壤的保水保肥特性,为保水剂在椰子树抗旱栽培中的合理施用提供理论依据。结果表明:塇土大颗粒保水剂具有稳定快速吸水的性能,有效吸水期较长,吸水倍率大,理论上能达到自身重量121.79倍;该保水剂吸附的水分可基本上全部释放,可释放的水分高达993 mg/g;该保水剂重复吸水时,吸水倍数有所下降,但重复8次的吸水倍数仍高达100倍以上,即有效使用期长;土壤中添加保水剂后可明显减轻水分渗漏,减少土壤中氮、磷、钾素的淋失,对添加肥料的土壤来说其保肥效果更佳。

Large granule water retaining agent(WRA)containing poly(acrylamide/potassium acrylate)was used to determine its capacity of water and fertility retention in the soil of the coconut plantation.The characteristics of WRA in absorption,release,and the retention capacity of water and fertility in the soil of coconut plantation by leaching test were determined.The results showed that WRA had stable and fast water absorption performance,with a long period of effective water absorption and a high water absorbency(the theoretical value upto 121.79).The amount of water absorbed by WRA was released almost completely,up to 993 mg per gram of WRA.WRA reduced its water absorbency after repeated water absorption,but its water absorbency could be up to 100 even after its water absorption was repeated for 8 times,indicating WRA had a long period of effective use for water absorption.WRA,when added into the soil,reduced water leakage significantly and mitigated the leaching loss of nitrogen,phosphorus and potassium in the soil.WRA had a better effect of fertility retention when added into the soil mixed with fertilizer.