保水缓/控释肥料的研究进展

肥料与保水剂复合一体化使用是水肥调控的重要技术，是肥料研究的国际前沿。该文主要对保水剂与化肥的复合方式与工艺，保水剂与肥料养分相互作用及其研究方法，以及保水及保水肥料应用的水肥效应方面的进展进行综述，并指出了保水缓/控释肥料研究存在的问题和今后努力的方向。保水剂与肥料可以通过物理混合(吸附或造粒)、包膜或化学合成3种方式结合为材料与功能复合一体化的保水缓/控释肥料，包膜和化学合成是高养分含量保水缓/控释肥料制备的先进工艺。肥料或盐影响保水剂的吸水膨胀及吸附作用，因肥料及盐的种类和离子电价而异。7 d溶解量法、土壤淋洗法及土壤培养法等是研究保水剂及保水缓释肥料养分吸附解吸的常用方法。保水剂或保水缓/控释肥料对一些养分的缓释作用报道基本一致，对土壤水分改善作用存在不一致的报道，与高盐含量和保水剂用量有关。保水缓/控释肥料今后发展方向应加强养分含量与吸水倍率指标标准、保水材料及其与肥料复合机制的创新、以及湿润及养分控释机理的研究，还应加强中试及产业化技术开发研究。

Research advances in slow/controlled-release water-storing fertilizers

The incorporating use of fertilizers with hydrogels is important practice of enhancing efficiency of fertilizer and soil water, and the frontier in international fertilizer research. In the article, a review was given on method and process of fertilizers combined with hydrogels, interaction of fertilizer nutrients with hydrogels and its research methods, and interactive effects of water and nutrients of hydrogels or slow/controlled release water-storing fertilizers(SRWAFs/CRWAFs) applied to soils, and existing problems and future directions to SRWAFs/CRWAFs. Hydrogels can be incorporated with fertilizers into slow/controlled release water-storing fertilizers by physical mixing(absorption or granulation), coating and synthesizing, the process of coating and synthesis is advanced technique to prepare SRWAFs/CRWAFs with high nutrient analysis. Fertilizers and salts influence swelling rate and absorption of hydrogels which depend on fertilizers and salt ionic valence. Reports on slow-release effects of hydrogels and SRWAFs/CRWAFs on nutrients are similar, information about the effects of hydrogels on soil water is conflict which is related to application rate of hydrogels and high salts in soils. From now on, emphasis should be made on criterion of nutrient content and absorbency index, innovation of water-absorbent materials and its incorporation process with fertilizers, and the mechanism of wetting and nutrient controlled-release of SRWAFs/CRWAFs, and also on research of development of pilot-plant and industrialization technology.