Snowflakes fall from the sky, and pieces of snowflakes bring people joy, but also bring people clean energy without extra investment. "Snow will bring good harvest" is a popular agricultural proverb in China. In the north, a thick layer of loose snow is like covering wheat with a quilt to keep out the cold. The cold nitrogen in snow is easily absorbed and utilized by crops. The low temperature of snow water can freeze the overwintering pests on the surface and bring benefits to agricultural production. So there is another agricultural proverb, "wheat covers three layers in winter and sleeps with steamed bread in the next year."

Snow has a wide range of functions, but it is of great benefit to mankind. First, it is beneficial to the growth and development of crops. Because of its poor thermal conductivity, covering the soil surface with a layer of snow cover can reduce the diffusion of soil heat and prevent the cold from invading the snow surface. Therefore, crops protected by snow can survive the winter safely. Snow can also store water for crops. In addition, snow can enhance soil fertility. According to the measurement, every 1 liter of snow.

Snow is both beneficial and harmful to people. In the mid-spring season in March and April, if it suddenly snows because of the cold wave, it will cause freezing cold. Therefore, the agricultural proverb says, "La Xue is a treasure, but Chun Xue is not good."

Effects of Snow on Human Health

In winter, the health care newspaper is covered with heavy snow. People often ignore the role of snow when watching Yushu Qionghua. Snow has many benefits to human health. It has long been recorded in Compendium of Materia Medica that snow water can detoxify and cure plague. People can use snow water to treat burns and frostbite.

Taking a bath with snow water often can not only enhance the resistance between skin and body, reduce diseases, but also promote blood circulation and enhance physical fitness. Drinking clean snow water for a long time can prolong life. This is one of the "secrets" of the old people who have lived in the deep mountains and forests for a long time.

Why does snow have such strange functions? Because the heavy water content of snow water is less than that of ordinary water 1/4. Heavy water will seriously inhibit the life process of living things. Some people have done experiments, and fish will die soon if they are put in water containing 30-50% heavy water. The most basic condition for the formation of rain and snow is that there must be "condensation nuclei" in the atmosphere. Solid impurities such as dust, coal particles and minerals in the atmosphere are the most ideal condensation nuclei. If the meteorological factors such as water vapor and temperature in the air reach certain conditions, the water vapor around these condensation nuclei will condense into snowflakes. Therefore, snowflakes can clean many pollutants in the air, so the air is particularly fresh after heavy snow every time.

According to the measurement, the density of new snow is generally 0.05-0. 10g per cubic centimeter. Therefore, the reflectivity of ground snow to sound waves is extremely low, which can absorb a lot of sound waves and contribute to noise reduction. ...