1. Absorb carbon dioxide and release oxygen (Comparison of photosynthetic effects of different types of urban green spaces)

Theoretically, each person needs a forest with an area of 10m2 or a green area of 25m2 lawn. ? World Environmental Protection Agency: Everyone should have 50m2 urban green space and 300m2 suburban green space.

2. Absorb harmful gases: Although harmful gases are not good for plant growth, many plants can absorb and purify them under certain conditions.

It is of great significance to choose tree species with high absorption and strong resistance for greening near the pollution source area where harmful gases are emitted, so as to prevent pollution and purify the air.

3. Absorb smoke and dust: Plants, especially trees, have obvious blocking, filtering and adsorption effects on smoke and dust. On the one hand, because of the dense branches and leaves, it has a powerful effect on reducing wind speed; On the other hand, due to the rough surface of leaves, there are fluff or sticky secretions, when the dust in the air passes through trees, it will attach to their leaves and branches.

4. Reduce the bacterial content in the air: Green space can reduce the bacterial content in the air. On the one hand, it reduces the dust above the green space, thus reducing the bacteria attached to it; On the other hand, many plants themselves have the ability to secrete fungicides, such as Platanus acerifolia, Sabina vulgaris, Pinus bungeana, Cedar, etc., which are all green trees with strong bactericidal ability.

5. Purify the soil?

The roots of plants can absorb a lot of harmful substances, thus having the ability to purify the soil.

Extended data

Urban green space refers to urban land with natural vegetation and artificial vegetation as the main forms.

It contains two levels of content:

First, green land within the scope of urban construction land;

Second, in addition to urban construction land, it has a positive effect on urban ecology, landscape, residents' leisure life and a better green environment. ?

Psychological function

Plants have certain psychological effects on human beings. With the development of science and technology, people's understanding of this function is deepening. In cities, there are fewer calming greens and blues, but more exciting and active reds and yellows. Therefore, the light in the green space can stimulate people's physiological vitality and make people feel calm psychologically.

Green makes people feel comfortable and can regulate people's nervous system. Plants of different colors absorb and reflect light in different ways. The green color of grass and trees can absorb ultraviolet rays harmful to eyes under strong light. Blue reflection is 36% and green reflection is 47%, which is suitable for human nervous system, cerebral cortex and retina of eyes. ?

reference data

Baidu encyclopedia-urban green space