缓释中微量元素肥料中不同种类养分释放性能研究

Study on the Nutrient Releasing of Slow-release Medium and Trace Element Fertilizer

利用自制的聚合物包膜缓释中微量元素肥料样品开展浸提试验,对比检测了钙、镁、铁、硼、锰、锌、铜7种不同营养元素离子在水浸提条件下的释放速率差异。累积养分释放率大小检测结果为:铜>铁>锰>锌>镁>钙>硼。结合缓释肥料养分释放机理,并通过同各元素离子半径大小进行对比,发现释放速率的快慢与离子半径大小基本一致。但硼元素的离子半径较小,释放速率却最慢。通过分析,认为缓释中微量元素颗粒中的硼酸原料在水浸提条件下,浸提液中的硼可能是以硼酸分子(H_(3)BO_(3))或硼酸根离子[B(OH)_(4)^(-)]形态存在。由于这些硼酸分子或硼酸根离子的半径显著增大了,所以释放速率迅速下降。

A leaching test was carried out on homemade samples of slow-release medium and trace element fertilizers,to compare the the releasing rates of these seven different ions in leaching,namely,calcium,magnesium,iron,boron,manganese,zinc,and copper.The detected cumulative release rates were:copper>iron>manganese>zinc>magnesium>calcium>boron.After studying the nutrient release mechanism of slow-release fertilizers,and comparing the ionic radius size of each element,it was found that the release rate was basically consistent with the ionic radius size,with boron as an exception.Its release rate is the slowest,with a relatively small ionic radius.Through analysis,it is believed that the boric acid in the slow-release medium and trace element particles may exist in the form of boric acid molecules(H_(3)BO_(3)) or borate ions[B(OH)_(4)^(-)] in leaching.Therefore,an obviously enlarged radius of these boric acid molecules or borate ions has significantly brought down the release rate.