Second, forests have natural epidemic prevention functions. Trees can secrete fungicides with strong lethality, kill germs and microorganisms in the air, and have a certain health care effect on human body.
Third, the forest is a natural oxygen factory. Oxygen is the basic condition for human life. The human body is breathing oxygen and expelling carbon dioxide all the time. It is common sense that healthy people will not die if they don't eat or drink for three or two days, but will die if they lack oxygen for a few minutes. Leaves produce one gram of glucose through photosynthesis, which can consume all the carbon dioxide contained in 2500 liters of air. According to theoretical calculation, every cubic meter of wood grown in the forest can absorb about 850 kilograms of carbon dioxide in the atmosphere. At the peak of tree growth, one hectare of broad-leaved forest can absorb one ton of carbon dioxide every day and produce 750 kilograms of oxygen.
Fourth, the forest is a natural muffler. With the development of transportation, especially in cities and towns, noise is more and more harmful to human beings. According to the research results, the noise is below 50 decibels, which has no effect on people; When the noise reaches 70 decibels, it will cause obvious harm to people; If the noise exceeds 90 decibels, people can't work for a long time. As a natural muffler, forest has a good anti-noise effect.
5. Forests can regulate climate. The dense forest canopy can absorb, scatter and reflect part of solar radiation energy in summer, thus reducing ground warming. Although most forest leaves wither in winter, dense branches can still reduce the wind speed blowing across the ground, reduce air flow, and play a role in heat preservation and moisture preservation.
Six, the forest changes the low-level airflow, which has the functions of preventing sandstorms and reducing disasters, conserving water sources and conserving water and soil. Due to the blocking and friction consumption of forest trunks, branches and leaves, the wind speed entering the forest area will be obviously weakened.
Seven, the forest has the function of dust removal and sewage filtration. Smoke, dust and waste gas emitted by industrial development seriously pollute the air and threaten human health. The folds and fluff on the leaves of tall trees, as well as the viscous oil and juice secreted by stomata, can intercept a lot of dust and have obvious blocking, filtering and adsorption effects.
8. Forest is the habitat of many kinds of animals, the growth place of many kinds of plants, and the most active area of biological reproduction on the earth. Therefore, forests protect biodiversity resources; Moreover, whether around the city or in the outer suburbs, forests are extremely valuable natural landscape resources.
Forests are areas with high density of trees. These plant communities cover a large area of the world and play an important role in reducing carbon dioxide, animal communities, hydrological turbulence regulation and soil consolidation, which is one of the most important aspects of the earth's biosphere. Forests include arbor forests and bamboo forests. Forest is a surface biological community mainly composed of trees. It is rich in variety, complex in structure and diverse in functions.