Plant communities.

the sum of all plants living in the same environment in a certain natural area. A forest, a meadow, and all the plants in a pond make up a flora. Within the community, the plants that live together are interconnected and interact to form an
organic
whole. The formation of each community is influenced by environmental conditions, which mainly depend on climate and soil conditions, so there are different types of community. For example, forest community, pool plant community, desert, grassland community and so on. Each plant community has certain structural characteristics, mainly manifested in a certain variety of components, the appearance of the community, vertical and horizontal structure and other aspects. Any plant community is composed of a certain plant species, each plant individual has its shape and size, they have their own requirements and reactions to the surrounding ecological environment, they are in different positions and play different roles in the community. The species composition that make up the plant community is the basis for the formation of the community structure. The better the environmental conditions, the more plant species there are in the community and the more complex the structure. In the rainforests of Xishuangbana, for example, there are more than 130,
kinds of higher plants that make up the community, while in a desert in Xinjiang, there are an average of only
6
species. The appearance of the community is an external feature of the community's long-term adaptation to the external environment. Under the condition of natural environment in a certain area, the community is represented as a certain appearance, and its appearance characteristics are not the same between different group types. The vertical structure of the community is manifested in the formation of the community. In terms of land-based plant community, the environmental factors that determine the stratation of the above-ground part are mainly light, temperature and humidity. Forest community can generally be divided into four basic structure levels, such as wood layer, shrub layer, herb layer and ground layer. Strat layering phenomenon is a special form of the relationship between plant community and environmental conditions, the richer the environmental conditions, the more layers of the community, the more complex the hierarchy; In the community between plants and plants, plants and the environment have a close relationship between each other, mutual constraints, mutual influence. There is mutual assistance and competition among species, and there is competition and mutual assistance among species, which keeps the community in constant change.。