Why is it forbidden to burn straw?

At present, it is the harvest season, and a new round of straw burning ban has begun again. While vigorously promoting the ban on burning straw, many farmers still have a wrong understanding of burning straw.

some people think that burning straw can burn all the weeds in it, but it is not. Although grass seeds exist with straw, the proportion of grass seeds particles is small, which is often located in the lower layer of straw near the ground. When straw burns, the flame is upward, and the density of carbon dioxide gas produced by combustion is higher than that of air, which makes the ground straw burn insufficiently. In addition, some grass seeds exist in the cracks of the soil, often the straw is burned out, but the grass seeds are safe and sound.

Some people think that after burning straw, it will be returned to the field. The main components of straw are cellulose, hemicellulose and a small amount of protein polysaccharide. After these organic substances are returned to the field, they are decomposed into humus and other components by microorganisms, which can improve the physical and chemical properties of soil. After burning straw, almost all organic matter, nitrogen and phosphorus are lost, and some potassium is converted into substances that are difficult to be absorbed and utilized by crops.

in my opinion, burning straw is a waste of straw resources. Straw can be used not only as fuel, feed and fertilizer, but also for planting edible fungi, making paper and producing new wall materials. Second, burning straw pollutes the atmospheric environment. Third, burning straw will cause fire, which may cause huge economic losses. Fourth, burning straw will increase the surface temperature of soil, burn a large number of soil microorganisms, and lose 65%-8% of soil moisture, which will make the soil hardened and drought-tolerant, and the ability of water absorption and moisture conservation will be greatly reduced.