天然有机物包裹控释尿素的养分释放特征及其肥效研究

为了探究木质纤维素类有机物在缓/控释肥上的应用效果，采用静水浸泡法，研究3种天然木粉包裹控释尿素在常温条件下的养分释放规律，并通过盆栽试验考察包裹控释尿素在白菜上的肥效。结果表明，包裹控释尿素对氮素养分有很好的控释效果，不同的包裹量表现出不同的释放模式；缓释期随着包裹量的增加而变长；盆栽试验证明，等养分控释尿素处理(CRU1)能够促进白菜的生长，白菜产量（鲜重）和氮素利用率比普通尿素处理(CCU)分别提高17.7%、12.4%，差异显著(P<0.05)；与普通尿素处理(CCU)相比，氮肥减量10%处理(CRU2)和20%处理(CRU3)的白菜产量（鲜重）差异不显著；等养分控释尿素处理(CRU1)白菜的硝酸盐含量增加不显著，施肥处理间白菜的品质没有显著差异。包裹控释尿素能够与白菜的营养需求匹配，减少对根的伤害，提高肥料利用率。

N-release Characteristics of Controlled Release Urea Coated with Natural Organic Material and Its Biological Efficiency on Chinese Cabbage

In order to study the nutrient controlling release effect of controlled release urea coated with natural wood flour, three kinds of controlled release urea were examined by water-extraction method at room temperature. Pot experiment was conducted to examine the effects of controlled release urea on the leaf chlorophyll content, yield, nutrient absorption, nitrogen utilization rate and quality indexes of Chinese cabbage. The results showed that, coated urea presented good performance with slow release, and the N-release model changed with the amount of coat material. Pot experiment proved that, equal amount coated urea treatment （CRU1） promoted the Chinese cabbage＇ s growth, yield （fresh weight） and nitrogen utilization of urea increased by 17.7% and 12.4% respectively, compared with the common chemical urea treatment （CCU）, and the statistic difference was significant （P〈0.05）. The reduction amount treatments of 10% and 20% （CRU2 and CRU3） had no significant difference with the common chemical urea treatment （CCU） in cabbage production （fresh weight）. There was no significant difference between all the nitrogen treatments in the quality of Chinese cabbage. Coated urea could match with the nutritional needs of Chinese cabbage, and imorove nitrogen use efficiency.