After urea is converted into ammonium bicarbonate, it is easy to decompose and volatilize on calcareous soil, which may cause nitrogen loss. Therefore, it is necessary to cover the soil in time after applying urea.

Long-term storage of green or partially green corn stalks after autumn harvest with silage can well preserve its nutritional components, and its texture is soft and fragrant, which can stimulate the appetite of cattle and sheep and solve the problem of forage shortage in winter and spring. At the same time, making silage saves half of the floor space compared with stacking the same amount of hay, and is also beneficial to fire prevention, rain prevention, mildew prevention and elimination of crop pests on straw.

Extended data:

Urea is easily soluble in water, and 105g is soluble in 100 ml water at 20℃, and the aqueous solution is neutral. There are two kinds of urea products. Crystalline urea is a white needle-like or prismatic crystal, which has strong hygroscopicity and caking after hygroscopicity, and its hygroscopic speed is 12 times faster than that of granular urea. ?

Granular urea is translucent, with a particle size of 1 ~ 2 mm, smooth in appearance and obviously improved in hygroscopicity. At 20℃, the critical moisture absorption point is 80% of the relative humidity, but at 30℃, it drops to 72.5%. Therefore, urea should be avoided to be stored in the open air in humid climate in midsummer. After adding hydrophobic substances such as paraffin wax in urea production, its hygroscopicity is greatly reduced.

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