People who pollute the environment always think that the land, sea and air on the earth are endless, so they never worry about sending tens of millions of tons of waste gas to the sky and dumping hundreds of millions of tons of garbage into the ocean. Everyone thinks the world is so big. What kind of waste is this? We were wrong. In fact, although the earth is large (with a radius of more than 6,300 kilometers), creatures can only live in the range from 8 kilometers above sea level to the seabed 1 1 km, and 95% of the creatures can only live in the middle range of about 3 kilometers. People have wantonly polluted this limited living environment from three aspects:

Marine pollution: mainly crude oil leaked from oil tankers and oil wells, pesticides and fertilizers used in farmland, sewage discharged from factories and acidic solutions from mines; They pollute most marine lakes. Therefore, not only marine organisms are harmed, but birds and humans may also be poisoned by eating these organisms.

Land pollution: garbage disposal has become an important issue in major cities. Tens of millions of tons of garbage every day, many of which cannot be burned or decomposed, such as plastics, rubber, glass, aluminum and other wastes, have become the number one enemy of urban sanitation.

Air pollution: this is the most direct and serious, mainly from carbon monoxide and hydrogen sulfide released by factories, automobiles and power plants. Every day, people get diseases of respiratory organs or visual organs because of contact with these dirty air. If we still ignore the warnings of experts, we will definitely be reduced to the point where there is no half an inch of pure land to live in.

Environmental pollution refers to the phenomenon that human beings directly or indirectly discharge substances or energy that exceed their self-purification ability to the environment, thus reducing environmental quality and adversely affecting human survival and development, ecosystems and property. Specifically, it includes water pollution, air pollution, noise pollution and radioactive pollution. Water pollution refers to the change of chemical, physical, biological or radioactive pollution characteristics of water body due to the intervention of some substances, which affects the effective use of water, harms human health or destroys the ecological environment, and leads to the deterioration of water quality. Air pollution refers to the phenomenon that the concentration of pollutants in the air reaches a harmful level, which destroys the ecological system and the conditions for the normal survival and development of human beings and causes harm to people and creatures. Noise pollution refers to the phenomenon that the environmental noise generated exceeds the national environmental noise emission standard and interferes with the normal work, study and life of others. Radioactive pollution refers to the appearance of radioactive substances or rays exceeding the national standards on the surface or inside of substances, people, places and environmental media due to human activities. For example, exceeding the national and local pollutant discharge standards, discharging pollutants in excess of categories, quantities and concentrations; Loading and transporting oil or toxic goods without taking measures to prevent spillage, causing the goods to fall into the water and causing water pollution; Illegal discharge of toxic and harmful substances into the atmosphere, causing air pollution accidents, and so on.

With the development of science and technology and the improvement of people's living standards, environmental pollution is also increasing, especially in developing countries. Environmental pollution is becoming one of the common topics in the world.

Due to people's insufficient expectation of the negative impact of highly developed industries and unfavorable prevention, three global crises have resulted: resource shortage, environmental pollution and ecological destruction. Humans constantly discharge pollutants into the environment. However, due to the diffusion, dilution, redox and biodegradation of atmosphere, water and soil, etc. The concentration and toxicity of pollutants will naturally decrease, which is called environmental self-purification. If the discharged substances exceed the self-purification capacity of the environment, the environmental quality will change adversely, endangering human health and survival, thus leading to environmental pollution.