What are the main manifestations of chemical fertilizers on soil pollution?
The pollution of soil by chemical fertilizers is mainly manifested in the following aspects:
First, excessive application of chemical fertilizers can damage soil structure, leading to soil compaction and reduced fertility. This is due to the fact that chemical fertilizers contain a large number of inorganic salts and acids and alkalis, which accumulate in the soil, resulting in changes in the physical and chemical properties of the soil, and poor aeration and water retention of the soil, thereby affecting the activity of soil microorganisms and reducing soil fertility.
Second, excessive application of chemical fertilizers can lead to soil pH imbalances. Different crops have different pH requirements, and the pH of fertilizers often deviates from the proper level. Excessive and long-term application of chemical fertilizers can cause soil pH to deviate from the appropriate range, affecting crop growth and yield.
Third, heavy metal elements in chemical fertilizers are also the main cause of soil pollution. Some heavy metal elements, such as mercury, cadmium, lead, etc., are high in chemical fertilizers, and long-term application will accumulate in the soil and enter crops and animals through the food chain, endangering human health.
In summary, the pollution of soil by chemical fertilizers is mainly manifested in soil structure destruction, acid-base imbalance, heavy metal element pollution and nutrient pollution. In order to protect soil health, chemical fertilizers should be applied rationally, the correct fertilization method and fertilization time should be selected, fertilizer management should be strengthened, and excessive fertilization and improper fertilization should be avoided. At the same time, it is necessary to strengthen soil monitoring and restoration, discover and solve soil pollution problems in a timely manner, and ensure soil ecological security and sustainable agricultural development.