包膜肥料氮释放特性及快速检测方法研究

Rapid measurement method of coated fertilizer nutrient release property

该文采用“盆栽法”和“水浸泡法”测试了美国Scotts公司生产的Osmocote聚合物包膜肥料，结果表明该肥料氮释放规律符合线性关系，“盆栽法”得出的肥效期为118．1d，与肥料标示的肥效期（31℃）3～4个月基本一致；国际常用方法和水浸泡法得出的肥效期分别为86．4d和54．7d，有一定的误差。文中提出了“强化浸泡法”，即以80℃、1：20（w／w）的2％盐酸溶液浸泡肥料，并用搅拌器以150r／min的速度搅拌上层溶液。建立了“盆栽法”与“强化浸泡法”测试结果的相关性方程，给出了工业生产中在线检测并预测肥料释放特性的方法，为编制肥料施用说明提供参考。验证结果表明，该法与“盆栽法”相比，平均绝对误差为0．525%，平均相对误差为1．71%。

＂ Potted plant method＂ and ＂water-marinating method＂ were used to measure Osmocote which is polymer-coated fertilizer from Scotts Co. of U. S.. The results showed that the N of fertilizer release property was in accordance with linear relationship, the nutrient release time of fertilizer in ＂potted plant method＂ was 118.1 d that matched the mark of fertilizer; the nutrient release periods in international common use method and ＂water-marinating method＂ were 86.4 d and 54.7 d with some errors. ＂Intensified marinating method＂ was put forward in paper that fertilizer was marinated in 80℃, 1 ： 20 ratio 2% hydrochloric acid solution and mixed round the upper solution at the same time. The paper established the relative equation between the results of ＂potted plant method＂ and ＂intensified water-marinatlng method＂ and presented the method which was used for online measuring and predicting fertilizer release property in industrial production, which afforded valuable references for compiling fertilizer introduction. The verified results showed that the average absolute error was 5.25% and the average relative error was 1.71% compared with ＂potted plant method＂.