On the earth, there are countless animals, plants and microorganisms of different sizes and shapes. Similarly, some animals, plants and microorganisms have the same genome, and individuals can mate with each other and produce normal offspring. These organisms with the same genome and can mate and produce normal offspring are a species. Animals, plants and microorganisms on the earth contain a variety of species, which is called species diversity.
Different individuals in the same species will be different in one way or another. For example, there are Persian cats, short haired cats, Siamese cats and other varieties. Even if they are rice, there are many differences, such as height, maturity and so on. The differences of different individuals in the same species are caused by alleles, DNA sequences, single nucleotide differences, etc., that is, a variety of individuals in the same species are caused by a variety of genetic structures, and the diversity of genetic structures is called genetic diversity.
All the creatures on earth live in a specific environment. The creatures living together in a specific environment are called communities. For example, there are specific organisms living together in specific areas such as forests, grasslands, rivers and lakes. These multiple organisms living together in forests, grasslands and lakes are communities, and they are connected with the surrounding inorganic environment such as water and sunlight to form a unique ecosystem. It can be seen that the ecosystem is also different and diverse.
Biodiversity usually refers to species diversity, genetic diversity and ecosystem diversity. The United Nations Convention on biological diversity defines biodiversity as: biodiversity refers to organisms from all sources, including terrestrial, marine and other aquatic ecosystems and their ecological complexes. This includes diversity within species, between species and ecosystems.
In addition, the diversity of human culture (such as nomadic life and mobile farming) can also be considered as an extension of biodiversity.
In various ecosystems, there are four basic components, namely, inorganic environment, plants (producers), animals (consumers) and microorganisms (decomposers). The organisms living together in each ecosystem depend on the food chain (or food web) to connect with each other. For example, in the ecosystem of "North" - giant fir, there are other plants, animals and microorganisms at the same time. It is plants (producers) that use photosynthesis to obtain energy from the sun and open the energy conversion and material cycle on the earth.
Animals are heterotrophic creatures and "consumers". They rely on food intake to obtain nutrients and energy needed for life activities. The vast majority of microorganisms are fungi. They can decompose complex organic matter into simple organic matter or inorganic matter, and obtain the material and energy they need. They are called "decomposers" and "beauticians" of nature. Without them, the earth would be full of biological remains and life would not be sustainable. All kinds of plants, animals and microorganisms play an important role in the energy conversion and material cycle on the earth. They contribute their indispensable strength in maintaining the balance of the ecosystem.
Various species provide human beings with rich food, fiber and energy. They also provide human beings with a full range of medicinal materials and sufficient industrial raw materials. Diverse organisms are also important resources for tourism and entertainment. With human activities on the earth, the survival of many species has been threatened, and the reduction of species will lead to ecological imbalance and threaten human survival. The protection of biodiversity plays an important role in human sustainable development.