论文部分内容阅读
尿素含氮量为44～46％,居固体氮肥之首。1斤尿素相当于2.2斤硫酸铵和2.7斤碳酸氢铵,所以有人把它叫氮肥中的“大力士”。尿素为白色的结晶或小圆粒,它是一种中性肥料,能完全溶解于水,适用于各种土壤和作物。尿素中的氮素以酰胺态存在,施入土壤后靠微生物分泌出的脲酶分解,变成铵态氮后才能被作物吸收利用,因而其肥效比硫酸铵等氮肥稍慢些(一般慢3～4天)。尿素不会给土壤遗留什么,连年施用也不能“板地”。
Urea nitrogen content of 44 ~ 46%, ranking first in solid nitrogen fertilizer. 1 kg of urea is equivalent to 2.2 kg of ammonium sulfate and 2.7 kg of ammonium bicarbonate, so it was called nitrogen fertilizer in the “Hercules.” Urea is white crystalline or small round grain, it is a neutral fertilizer, can be completely dissolved in water, suitable for a variety of soil and crops. Nitrogen in urea is present in amide form. After being applied to the soil, urease secreted by microorganisms is decomposed into ammonium nitrogen to be absorbed and utilized by crops. As a result, its efficiency is slightly slower than nitrogenous fertilizer such as ammonium sulfate (usually 3 ~ 4 days). Urea will not leave anything to the soil, year after year application can not “plate.”