How many trees are there?

1, classified by tree growth type:

(1) tree, the tree height (generally 6 meters to tens of meters), the trunk is obviously tall.

(2) Shrubs and trees are short (generally less than 6 meters) and the base of the trunk is short.

(3) Rattan, a woody plant (such as Parthenocissus tricuspidata), can be wound or attached to other things to grow upwards.

(4) creeping seeds, stems, branches, etc. Crawling (as a spreading cypress).

2, according to the adaptability to environmental factors:

(1) According to the heat factor, there are tropical tree species, subtropical tree species, temperate tree species and sub-frigid tree species.

(2) According to the water factor, it can be divided into drought-tolerant tree species (fractional grade) and moisture-tolerant tree species (fractional grade).

(3) According to illumination factors, each category can be divided into positive trees, neutral numbers and negative trees.

(4) According to air factors, there are four categories: wind-resistant tree species, smoke-resistant tree species and toxic gas-resistant tree species, dust-resistant tree species and health-care tree species (which can secrete volatile fungicides and aromatic molecules beneficial to human body).

(5) According to soil factors, acid-loving tree species, alkali-tolerant tree species, barren tree species and coastal tree species.

3, according to the ornamental characteristics of trees:

(1) tree viewing tree (shape tree);

(2) foliage trees (mesophyll);

(3) ornamental trees (flowers and trees);

(4) viewing fruit trees (fruit trees);

(5) root tree (root tree);

4, according to the purpose of the classification of trees:

(1) single tree (solitary tree, specimen tree, shape tree);

(2) Shading trees; Street trees; Protective tree; Forest subordination;

(3) flowers and trees; Rattan wood; Hedgehog and green sculpture;

(4) Ground cover plants; Roof planting; Pile landscape class; Indoor greening and decoration.

Extended data

Trees can regulate climate, purify air, prevent wind and noise, prevent soil erosion, landslides and other natural disasters. They are man's best friends. Trees are oxygen factories, and 1 hectare broad-leaved forest can absorb 1 ton of carbon dioxide and release 0.73 ton of oxygen in 1 day.

Trees are dust filters. When the airflow with large dust content passes through the forest, with the decrease of wind speed, the dust with large particles in the air will fall rapidly. In addition, some trees have fur on their skin or can secrete grease, which can stick dust to their bodies, thus greatly reducing the dust content in the airflow through the forest.

Trees are experts in sterilization. Many trees secrete fungicides during their growth, killing all kinds of germs brought by dust. According to the survey, there are 4 million department stores, 580,000 are on the boulevard, 65,438+000 are in the park, and only 55 are in the forest area. The difference of bacterial content in the air between forest areas and department stores is more than 70 thousand times.

In addition, trees are natural reservoirs, natural silencers and natural air conditioners.

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