包膜尿素的养分释放特征及其肥效

应用固-液反应包膜工艺，采用4种改性的无机包膜材料，试制出了成本较低的包膜缓释尿素，用水中溶出率法测定了包膜缓释尿素的养分释放特征，应用盆栽水稻评价了包膜缓释尿素的肥效，并与国外的有机缓释氮肥（Methylene Urea）和高聚物包膜复合肥（Osmocotte）进行了比较，表明固-液反应型包膜尿素具有较好的养分缓释效果，4种包膜尿素与等氮和等重常规尿素相比，栽培水稻都有一定的增产作用，并提高了肥料利用率，其中LU增产最显著，比等氮和等重尿素处理分别增产41．5％和35．7％，肥料当季利用率达到43．9％，好于国外的有机缓释氮肥和高聚物包膜复合肥。养分释放特征与水稻氮素营养特征较为接近，可为水稻一次性施肥所用。

Nutrient Release Characteristic of Coated Urea and Its Efficiency on Rice

Coated urea was made by solid-liquid reaction technology using the nonmetal minerals as coated film material. By the means of water dissolution, the nitrogen release character of 4 type coated urea were researched that nitrogen release rate of solid-liquid reaction SRF with different films were greatly different. The results of rice pot experiment using the coated urea and overseas SRFS show that suitable release rate was critical for increasing crop yield and nutrient efficiency. Rice biomass, grain yield and N use efficiency of 4 type coated urea were significantly higher than that of urea which use the same amount of nitrogen or the same weight of fertilizer. Compared with the Methylene Urea and Osmocotte, velocity of nutrient release rate of LU is consistent to nutrient requirement of rice.