Hazards caused by soil environmental degradation

Agricultural land has been heavily fertilized with single chemical element fertilizers, such as ammonium carbonate, thiamine, diamine, urea and other bulk element fertilizers since the 1970s and 1980s. These fertilizers are fast absorbing and increase the yield though. However, it also caused the deterioration of the general soil environment. Due to the massive input of chemical fertilizers, a large amount of acid ions such as NO3-/SO42-/HPO4- gradually accumulate in the soil, making the soil pH gradually decrease. The resulting soil is hard and slaty, and the land is always watered and cracked on sunny days. The deterioration of the soil's general environment causes the following hazards.

1. Plants grow slowly and become sub-healthy. Each plant has a suitable pH range, and the majority of plants grow in a slightly acidic and slightly alkaline environment. However, the presence of a large number of acid ions makes the plant root system unable to absorb and secrete substances normally, causing the root nutrition to fail to keep up. Roots are the basis of plant growth, and the lack of his nutrition directly affects the growth of the whole plant. Even, it can accelerate the weathering of primary and secondary minerals containing aluminum in the soil and release large amounts of aluminum ions, forming plant-absorbable forms of aluminum compounds. Long-term and excessive absorption of aluminum by plants can lead to poisoning and even death.

2. Low utilization rate of fertilizer and large investment. After years of fertilizer input, the soil minerals themselves have fixed a large amount of phosphorus, potassium and other nutrients, reaching a saturated state. If you apply fertilizer again, not only will it not be adsorbed by the soil, but it will be lost in the water, causing the soil to become more acidic. Soil acidification plant roots can not absorb nutrients poor growth, farmers tend to increase fertilizer inputs, which will further aggravate the soil acid ion concentration, resulting in a vicious circle.

3. Easy to breed germs, produce disease. Soil acidification will lead to some beneficial microbial colonies reproductive capacity and living capacity decline, or even die. On the contrary, it will make some harmful microorganisms take the opportunity to multiply, and then infect the roots of plants spread throughout the body. For example, root rot of some crops is caused by the invasion of harmful microorganisms.