The plants in the field have a patchy mosaic distribution, which reflects the structure of the commu

This depends on what kind of surface it is on.

If it is an area with little difference in elevation, the species are different in different areas of the surface, reflecting the "horizontal" structure of the community. For example, the distribution of different species from water bodies to wetlands, to plains, and then to relatively arid areas, reflects the horizontal structure of the community.

From the plains to the mountains, the vertical change of altitude is obvious, and different species are the same, reflecting the "vertical" structure of the community.

Whether it is the horizontal structure or the vertical structure of the community, the distribution of species changes with the change of the environment, which belongs to secondary succession, which shows the complexity of the ecosystem structure and the self-regulation ability of the ecosystem.

According to the morphology, structure and living habits of plants, the plant kingdom can be divided into 7 main groups, namely: algae, fungi, lichens, bryophytes, ferns, gymnosperms and angiosperms. Among them, algae, fungi and lichens belong to the lower plants; Mosses, ferns, gymnosperms and angiosperms are higher plants.

a. The spatial structure of the community is divided into vertical structure and horizontal structure, and light is the main factor affecting the vertical structure of the plant community.

b. Interspecific competition promotes the full utilization of the first colony resources, causes the differentiation of interspecific niches, and increases the diversity of species in the community.

c. The main feature of the horizontal structure of the plant community is its mosaic, which is caused by the uneven distribution of plant individuals in the horizontal direction.

d. The study of the spatial structure of the community has guiding significance for the spatial configuration of plants in vegetation restoration

1 There are usually many individuals of each plant on the earth, and they are usually distributed in a certain area, which is the distribution area of the plant. For example, the endemic species of Pinus tabuliformis in China are distributed in the area of Shenyang in the east, Helan Mountain in the west, Yinshan in the north, and northern Sichuan in the south, which is the distribution area of Pinus tabuliformis. Plant taxonomic units (families, genera, species) at any level have corresponding distribution areas, for example, the genus Arborvitae is only found in eastern China.

The distribution area of the research department and genus should be based on the distribution area of the species. Therefore, the most basic and important research object in the study of plant distribution area is the distribution area of species.

It is important to note that no one plant covers the entire range of its range, and the extent to which each plant is found in the range is not the same. The degree of plant overfill depends on the frequency of recurrence in suitable habitats, the ecological habits of plant species, the ability to form clusters, the ability to compete with other species, and historical factors.

The evolution of plants: primitive algae plants (primitive bryophytes and primitive ferns) primitive seed plants (including primitive gymnosperms and primitive angiosperms), and angiosperms have flowers and fruits compared with gymnosperms, which make them more reproductive, have a higher survival rate of offspring, and have stronger adaptability, which is also more advanced Algae plants have no division of roots, stems, and leaves, and most of the reproduction is low-level spore reproduction, which is the lowest plant Therefore, the group of plants from low to high is as follows: algae plants, Bryophytes, ferns, seed plants

Therefore, d

The main taxa (plant phylogenetic tree) of the eight lower plants of biology in Beijing Normal University are taught in sections.

D test question analysis: The process of biological evolution is from simple to complex, from aquatic to terrestrial, from low to high, and the evolution process of plants is algae, bryophytes, ferns, gymnosperms, angiosperms.

Comments: This question is a basic question, and the key to solving this question is to be proficient in the process of biological evolution, which can be combined with the biological evolution tree for memory.