化肥是一种速效性肥料,含有效成分比较高,对作物种子发芽和出苗有着不同的影响,氨水和碳酸氢铵等碱性较强的化肥施入土壤后,在分解时会有一部分氨气挥发出来,容易烧伤作物种子及幼根而影响出苗;磷酸二铵和尿素等施入土壤里,由于溶解得比较快,也易造成土壤溶液局部浓度过高而烧伤作物种子及幼根。尤其是尿素含氮量达46%,浓度大,有的又含有缩二脲成分,对作物种子及幼根有一 Fertilizer is a quick-acting fertilizer, which contains relatively high effective components, which have different effects on germination and emergence of crop seeds. After ammonia and ammonium bicarbonate and other strong alkaline fertilizers are applied to the soil, part of the ammonia Volatile, easy to burn crop seeds and young roots and affect the emergence; DAP and urea and other facilities into the soil, due to dissolve faster, but also easily lead to local high concentrations of soil solution and burn crop seeds and young roots. In particular, urea nitrogen content of 46%, the concentration of large, and some contain biuret ingredients, on the crop seeds and young root has a