尿素,白色或带浅黄色颗粒状结晶,含氮量为46%左右,是固体化肥中含氮量最高的一种,其制造和运输成本比其他氮肥低,是一种很有发展前途的化肥。尿素施入土壤后,经微生物的作用,在春天约7～10天,在夏天约2～3天就转化为碳酸铵或碳酸氢铵,再被作物和土壤粘粒吸收。尿素无论施在旱 Urea, white or with light yellow granular crystals, the nitrogen content of about 46%, is the highest nitrogen content in solid fertilizers, its manufacturing and transportation costs lower than other nitrogen fertilizers, is a promising fertilizer . Urea into the soil, the role of microorganisms, about 7 to 10 days in the spring, about 2 to 3 days in the summer into ammonium carbonate or ammonium bicarbonate, and then absorbed by crops and soil clay. Regardless of urea in the drought