自制缓控释尿素的缓控释性能研究

Study of Controlled Released Effects of Homemade Coated Urea

[目的]为了提高肥料利用率,缓解由于化肥的大量施用带来的环境污染问题,推动农业的可持续发展。[方法]对自制的以硅藻土为载体包膜尿素的养分释放规律及所用载体硅藻土的保水、保肥性质进行了研究。[结果]硅藻土保水、保肥效果较好,是很好的缓控释载体材料。水溶试验和土柱淋溶试验表明,聚乙烯醇进行包膜后起到一定的缓释效果,但膜层结构疏松,缓释效果不明显,用松香和石蜡密封后膜层致密度提高,缓释效果显著提高,且养分释放速率较均匀,松香和石蜡密封后的包膜尿素更明显地降低了氮素由于淋溶造成的损失,增加了土壤中残留的氮素含量,从而使氮肥具有更高的利用效率,且所用的包膜材料松香、石蜡以及聚乙烯醇在土壤中可自然降解,不会对土壤造成二次污染。[结论]所研制的肥料不仅利用率高,而且是环保型肥料,对减少资源浪费、保护生态环境都有重要的意义。

[ Objective ] The research aimed to improve the utilization rate of fertilizer, ease the problem of environment pollution brought by the large amounts of fertilizer and promote agricultural sustainable development. [ Method] The nutrient release rules of coated urea with diatomite as carrier and water and fertilizer retention of diatomite was studied. [ Result] Water and fertilizer retention effect of the diatomite is good, which is good materials for controlled release carriers. The water soluble experiment and soil column leaching experiment showed that PVA coated urea had little controlled release effects, but the film structure was loose, controlled release effect wasn＇ t obvious. Density was increased to film sealed with rosin and paraffin, and controlled release effect was improved obviously. The nutrient release rate was uniform. The coated urea sealed with rosin and paraffin wax reduced the tossing N due to leaching more significantly, and increased residual nitrogen content in soil, so the nitrogen utilization rate was higher. And the used coating materials rosin and paraffin and polyvinyl alcohol in the soil could be naturally degraded, which wouldn＇t cause secondary pollution in soil. [ Conclusion] The fertilizer not only had a high utilization rate, but also was a environmental friendly fertilizer. It could reduce the waste of the resources, and had great significance for the protection of the ecological environment.