Man and environment

The composition of the natural ecosystem of the four-in-one relationship between man and the natural environment; Establishment of ecological balance between food chain and food web

Natural Material Cycle, Bioenergy Pyramid and Deforestation —— Rational Development and Utilization of Natural Resources in Flood and Drought Disasters

Establish nature reserves, protect the earth's green barrier and protect precious wild animals.

Man and the natural environment

The natural environment is the material basis for human survival and reproduction; Protecting and improving the natural environment is the prerequisite for human beings to maintain their own survival and development. These are two aspects of the relationship between human beings and the natural environment, and the lack of one will bring disaster to human beings.

The natural environment in which we live is the surface of the earth. Air, water and rocks (including soil) constitute the atmosphere, hydrosphere and lithosphere. At the intersection of these three circles, there is a biological biosphere. Under the action of solar energy, these four circles carry out material circulation and energy flow, so that human beings (creatures) can survive and develop.

According to scientific determination, the proportion of more than 60 chemical elements in human blood is very similar to that in the earth's crust. This shows that man is the product of the environment. The relationship between man and the environment is also manifested in the exchange of substances in the human body and substances in the environment. For example, the human body inhales oxygen through metabolism and exhales carbon dioxide; Drinking clean water and eating rich food can maintain the development, growth and inheritance of the human body, and make the substances in the human body exchange with those in the environment. If this balance relationship is destroyed, it will endanger human health.

In order to survive and develop, human beings need to obtain resources from the environment. In the early days, due to the small population, human beings had no obvious influence and destruction on the environment. For a long time, natural conditions have dominated the fate of mankind. In the slash-and-burn era, in order to feed themselves, survive and develop, human beings began to destroy forests and open up wasteland, which destroyed the environment to some extent. As a result, environmental problems caused by human factors have emerged. However, due to the low level of productivity at that time, the impact on the environment was not great.

During the industrial revolution, after human beings learned to use machines, their productivity was greatly improved and their impact on the environment was also increased. In this century, the ability of human beings to use and transform the environment has never been improved, and the scale has gradually expanded, creating huge material wealth. It is estimated that the agricultural products obtained by modern agriculture can feed 5 billion people, while the green plants produced by photosynthesis and the animals they feed on the original land can only feed 10 million people. It can be seen that human beings have gradually occupied a dominant position in the environment.

However, serious environmental pollution and ecological destruction have also appeared in front of human beings. Air pollution is serious, water resources are in unprecedented shortage, forests are destroyed, cultivated land is reduced, a large number of species are on the verge of extinction, and the natural environment on which human beings depend is in crisis. The deteriorating environment has put forward to mankind that protecting nature and maintaining ecological balance are the most urgent problems today.

The nature of the quaternity.

There are about 2 million kinds of creatures in nature. They combine with each other to form a biological community, which depends on the nutrients in the air, water and soil on the earth's surface for survival and development. These biological communities depend on each other in a certain range and region and form a dynamic balance system in the same living environment, which is called an ecosystem. Ecosystem includes animals, plants, microorganisms and their surrounding abiotic environment (also known as inorganic environment and physical environment), which is a four-in-one nature.

There are large and small ecosystems in nature. As small as a drop of water, a meadow, a pond, etc. The big ones are lakes, oceans, forests, grasslands and so on. Pond is a typical ecosystem: there are all kinds of aquatic plants, aquatic animals, bacteria and fungi in the pond, as well as the abiotic environment such as water, sediment, sunlight and temperature necessary for the survival of these organisms. Aquatic plants use solar energy for photosynthesis, transforming nutrients in water and sediments and carbon dioxide in the atmosphere into organic matter and storing it in plants; Small zooplankton feed on phytoplankton; Zooplankton and rooted plants are also eaten by fish; The residues of aquatic plants and aquatic animals are finally decomposed into inorganic substances by bacteria, fungi and saprophytes in water and sediments, and released into the environment for plant reuse. This constitutes a complete ecosystem and becomes the basic activity unit of nature. Its function is material circulation and energy flow.

All the components of an ecosystem are interrelated. If human activities interfere with a certain part, the whole system can automatically adjust and remain unchanged. For example, after the fish in the pond are caught, the natural enemies of aquatic plants and zooplankton decrease, and aquatic plants and zooplankton will multiply rapidly, which is of great benefit to fish reproduction. The more diverse the components of an ecosystem are, the more complicated the way of energy flow and material circulation is, and the stronger the adjustment ability is. However, the regulatory capacity of the ecosystem itself is limited. If human beings intervene on a large scale, automatic adjustment will become useless and the ecological balance will be destroyed. In the 1930s, due to the large-scale reclamation of western grasslands in the United States, the vegetation was severely damaged and the ground lost protection, which eventually triggered the "Black Storm" event, which scraped away more than 300 million tons of soil and reduced the national winter wheat production by more than 5 billion kilograms every year.

With the increasing ability of human beings to use and transform the environment, primitive ecosystems such as virgin forests and polar regions are rare, and people are replacing them with a large number of semi-artificial ecosystems such as breeding lakes, firewood forests and villages, and artificial ecosystems such as cities and factories. However, human beings gradually realize that they and their surroundings are a whole, and consider their own affairs and environment as a system, resulting in "human ecosystem" and "social ecosystem" in order to better maintain the balance between human beings and the environment.

Composition of ecosystem

An ecosystem consists of producers, consumers, decomposers and abiotic substances (inorganic world). They each play a specific role and form an overall function, which makes the whole ecosystem run normally.

Producers refer to green plants, including unicellular algae and some bacteria that can convert inorganic substances into organic substances. The leaves of green plants contain chlorophyll, which can carry out photosynthesis, convert solar energy into chemical energy and inorganic matter into organic matter to meet the needs of their own growth and development, and become the food and energy source for all living things and human beings on earth. Therefore, green plants are producers of ecosystems.

Consumers mainly refer to animals. They can't directly use external energy and inorganic substances to make organic matter, but consume producers for a living. Herbivores eat plants directly and are called first-class consumers, such as locusts and grasshoppers. Carnivores that feed on herbivores are called secondary consumers, such as frogs and toads. Animals that feed on carnivores are called tertiary consumers, such as snakes and owls. These consumers are an extremely important part of the ecosystem. It controls the self-regulation ability of the whole ecosystem, especially the excessive growth and reproduction of producers.

Decomposition refers to various microorganisms with decomposition ability, including some lower protozoa, such as soil nematodes and flagellates. The decomposer is the "cleaner" of the ecosystem. They break down the bodies of animals and plants into simple inorganic substances and put them back into the abiotic environment. If there is no decomposer, dead organisms will pile up, so that nutrients can't circulate between living and non-living, and eventually the ecosystem will become a source without water. The number of decomposers in the ecosystem is amazing. It is estimated that in 1 10,000 square meters of farmland soil, the weight of bacteria can reach 8 kg.

Abiotic substances, that is, the inorganic world, refer to all kinds of inanimate inorganic substances and natural factors in the ecosystem.

The components of the ecosystem have division of labor and cooperation. Producers directly or indirectly provide food for consumers and decomposers; Consumers control the number of producers within the range that abiotic environment can bear; The residue and excrement of producers and consumers are finally decomposed into inorganic substances by decomposers for reuse by plants. It is the coordination and unity among producers, consumers, decomposers and abiotic environment that enables the ecosystem to continue to play its role.

Food chain and food web

There is a proverb in China: "Big fish eat small fish, small fish eat shrimp, and shrimp eat mud balls." The creatures in the ecosystem form a chain through this relationship between eating and being eaten, which is called food chain.

According to the relationship between organisms, the food chain mainly has the following three types:

One is the predatory food chain, which is based on plants, from plants to small animals to big animals. The latter can prey on the former: grass → locust → frog → snake → eagle, which belongs to this type.

The second is the parasitic food chain, which is based on large animals. Small animals are parasitic on large animals: birds → fleas → protozoa → bacteria → viruses, which belong to this type.

The third is saprophytic food chain, also known as decomposition chain, which breeds bacteria, fungi and some soil animals from dead animal and plant residues, belonging to this type: plant residues → earthworms → nematodes → arthropods.

Every link in the food chain is called trophic level. Any living thing belongs to a certain trophic level. In any food chain, the latter animal can only eat, assimilate part of the energy provided by the former animal and consume part of the energy through metabolism. The latter can only store 5-20% of the energy absorbed from the former. That is to say, energy flows step by step along the trophic level of the food chain, and decreases continuously. Generally speaking, there are no more than five trophic levels in the food chain. In the ecosystem, the feeding relationship between biological components is very complicated. The same plant will be eaten by different animals, and the same animal will eat more than one food. There is a complex relationship between the biological components in the feeding relationship, and various food chains are intertwined and connected to form a network structure, which is called food web. Food web is a common and complex phenomenon in ecosystem. Energy flow, material migration and transformation are carried out through food chain or food web.

All kinds of organisms in the food chain interact and restrict each other, and they are linked one by one. If a link fails, the chain will lose its integrity and the ecosystem will be disordered. After World War II, after the South African expedition landed on Maris Island in Antarctica, several mice on board were also brought to the island. Because rats have no natural enemies, two years later, the island became a rat island. In order to kill rats, the expedition brought four domestic cats. As a result, there are fewer and fewer mice, and cats multiply rapidly, which eventually leads to great disaster. 60 thousand cats eat more than 600 thousand birds every day. In order to save birds, South African authorities used helicopters to shoot cats and sent hundreds of soldiers to kill them. It can be seen that the food chain has a very important impact on the environment and plays an important role in maintaining ecological balance.

Various human activities will discharge wastes into the environment. People also unconsciously ingest harmful substances through the food chain, and cancer chooses this route to lurk secretly. According to the survey of American Cancer Research Center, there are about 300 kinds of cancers in American freshwater fish, and cancer can be observed in any part of fish. Therefore, for the health of future generations, we must protect the environment.

Establish ecological balance

Like people, ecosystems have a process from infancy to maturity. When the ecosystem develops to a mature stage, its structure and function, including the composition of biological species, the proportion of biomass, energy flow and material circulation, are in a relatively stable state, which is called ecological balance. For example, fish in ponds feed on zooplankton. After the fish died, the microorganisms in the water decomposed the fish into compounds and became the food for zooplankton. Zooplankton feeds on phytoplankton, while fish feed on zooplankton. In this way, a certain ecological balance has been established among microorganisms, zooplankton and fish in the pond.

Generally speaking, the richer the species in a mature ecosystem, the more complex the food web, and the material circulation and energy flow can be carried out through various channels. If one link is blocked, other links can compensate. For example, falcons feed on rabbits, voles, sparrows and snakes. When rabbits and snakes were killed, falcons turned to sparrows and voles. Of course, there is a certain limit to this self-regulation ability. If it exceeds the limit, the balance will be destroyed and even lead to ecological crisis. When European immigrants first arrived in Australia, they found that there were green grass here, so they vigorously developed the cattle industry. Later, cow dung became a disaster, which led to pasture degradation and flies breeding. Therefore, dung beetles were introduced to restore the original appearance of the pasture.

There are two factors that affect ecological balance: natural and man-made. Volcano eruption, lightning fire, earthquake, debris flow, etc. Are all natural factors; Over-cultivation, grazing, indiscriminate hunting and so on are all human factors. The destruction of ecological balance is mainly caused by man. For example, the Aswan Dam in Egypt blocked fertile silt and made the land in the lower reaches of the Nile barren; The reduction of nutrients in rivers has affected the fishery production in the Nile Delta and the Mediterranean, and the catch of sardines in Egypt has also decreased. For example, in the mountainous areas of northern India, all forest resources were cut down, which triggered the catastrophic flood of 1978. As a result, more than 2,000 people were drowned and 40,000 livestock were washed away.

Ecological balance is a dynamic balance, in which all kinds of material circulation and energy flow occur all the time. Although this kind of balance system is quite sensitive to external interference, it does not mean that human beings cannot use and transform the environment. In order to be more conducive to their own survival, human beings can completely establish a new balance. The "Sangtang" in the Pearl River Delta of China has promoted the production of mulberry, silkworm and fish, and is a successful example of agricultural ecological balance. In addition, the transformation of the Great Northern Wilderness into a "Great Northern Warehouse" by our people is also a typical example of rebuilding a high-quality ecological balance.

Material circulation in nature

Biological organisms are composed of about 40 elements, among which carbon, hydrogen, oxygen, sulfur and phosphorus are the most important elements, all of which come from the environment and constitute biological individuals and biological communities in the ecosystem.

Producers convert inorganic substances into organic substances for consumption by consumers; The wastes produced by consumers and the residues of producers are digested by decomposers, converted into inorganic substances, and returned to the environment for plant reuse.

There are countless such material cycles on the earth, which merge into the total material cycle of the biosphere. Take the carbon cycle in the biosphere as an example. Photosynthesis of green plants removes carbon dioxide from the atmosphere, synthesizes carbohydrates and stores them in the body. Herbivores and carnivores absorb this nutrient through the food chain respectively. The respiration of animals and the decomposition of animal and plant residues by microorganisms discharge carbon into the atmosphere in the form of carbon dioxide. Organic residues that are not completely decomposed are buried underground, piled up on the seabed and converted into coal, oil and natural gas. While mining fossil fuels, human beings also emit a lot of carbon dioxide into the atmosphere during fuel combustion.

Like carbon, almost all nutrients in the ecosystem circulate between biological and abiotic environments. The smooth progress of material circulation makes all parts of the ecosystem coordinate and plays an important role in the self-regulation of the ecosystem. If human beings intervene on a large scale, the material circulation can not be carried out smoothly, which will cause serious environmental pollution and destruction and lead to ecological imbalance. In recent decades, human activities have intensified, a large number of minerals have been mined from underground, and some substances that did not exist in the natural environment have been artificially created, which has had an unprecedented impact on the material cycle. Some substances are partially enriched or lacking, resulting in environmental effects that are not conducive to biological and human survival. For example, people burn a lot of fuels such as oil and coal, and the forest area is greatly reduced, which will increase the concentration of carbon dioxide in the atmosphere. Carbon dioxide in the atmosphere gathers near the surface of the earth, just like the diaphragm of a greenhouse, which prevents geothermal energy from losing to outer space and produces the greenhouse effect. It is estimated that if we continue to burn fossil fuels at the current rate, by 2050, the global average temperature will rise by 3℃, with disastrous consequences.

Biological energy pyramid

When people study the structure of food chain and food web, the biomass, energy and individual number of each trophic organism are arranged in order of trophic level and depicted as a map, which is similar to the ancient building-Egyptian Pyramid. People call this kind of figure "ecological pyramid".

There are three types of ecological pyramids: energy pyramid, quantity pyramid and biomass pyramid. The energy pyramid represents the energy distribution relationship between different trophic levels. The pyramid of food chain and food web is determined by the objective law of energy flow in ecosystem. The energy flow in the ecosystem rises step by step along the trophic level, and the energy is getting less and less, which makes the energy of the previous trophic level only meet the needs of a few organisms in the latter trophic level. Generally speaking, only about 10% of the energy of each level organism is transferred to the next level organism. Due to the reduction of energy, the number of individuals in living things has also decreased sharply. If there are 500 kilograms of phytoplankton in a pond to maintain the life of 50 kilograms of zooplankton, these 50 kilograms of zooplankton can only feed 5 kilograms of fish, and these 5 kilograms of fish can only increase the weight of young people aged 18 by 0.5 kilograms. For example, tigers feed on sheep and deer, while sheep and deer feed on grass, and the energy decreases rapidly along the food chain from grass to sheep and deer to tiger, so there is not much food energy available for tigers to eat, and the number of tigers is not much. Therefore, there has always been a saying in China that "one mountain cannot accommodate two tigers", which shows that it is impossible to support many tigers at the top of the energy pyramid in a limited living environment.

No matter from biomass, energy or the number of individuals, they all decrease in a pyramid shape. This is the characteristic of the nutritional structure of the ecosystem.

The evil consequence of deforestation-floods and droughts

The forest is the patron saint of nature. One of its important functions is to conserve water and soil. In rainy season, the forest can intercept raindrops through canopy and fallen leaves on the ground, reduce the impact of raindrops on the ground, increase the speed of rainwater infiltration into the land and the ability of soil to conserve water, and reduce the surface runoff formed by rainfall; The tangled roots of trees can protect the soil and reduce the erosion of rain on the soil. If the soil is not protected by forests, it will lose its ability to conserve water. When the heavy rain comes, the turbidity current is rolling, and a thin layer of soil that people have spent thousands of years cultivating will be washed away by the rain. These sediments flow into the river, which in turn silts up the reservoir and makes it lose its water storage capacity. Forests conserve water, and 70% of rainfall will seep into the ground. If there is no forest, there will be flooding and drought.

Rational development and utilization of natural resources

Rational development and utilization of natural resources is one of the important measures to protect the environment.

Natural resources can be divided into three categories: first, ecological resources (constant resources), such as light, heat, water, wind, tides and so on; The second is biological resources (renewable resources or renewable resources), such as animals, plants, microorganisms, soil and so on. The third is mineral resources (non-renewable resources or non-renewable resources), such as natural gas, coal and oil.

Natural resources are the basic source of human production and living materials and the premise and foundation of the development of social civilization. If resources are degraded and exhausted, it will hinder the development of production. If the mining industry practices blind mining, it will bring about the exhaustion of mineral resources. Without water, air, sunshine, land and so on, people can't live. Once these resources are scarce, it will threaten the survival and development of mankind.

Although the total amount of natural resources in China is large, the per capita possession is small. For example, the potential value of mineral resources is the third in the world, but the per capita possession is lower than that of many countries. Another example is water resources, which is only 2,700 cubic meters per capita, far below the world average of per capita 1 1000 cubic meters. For example, if you own forest land, the per capita area is only 1.7 mu, while the per capita area of forest land in the world is 15.5 mu.

The development and utilization of natural resources will inevitably affect and change the environment; At the same time, China's ability to protect the ecological environment is low, which affects the development and utilization of natural resources. For example, if the development and utilization of land resources by human beings do not conform to the local ecological environment characteristics, it will destroy the ecological balance and cause serious natural disasters.

Rational development and utilization of resources is the best protection for the environment. In this regard, people must establish a correct view and realize the finiteness of natural resources. As far as a certain resource is concerned, it is not inexhaustible under certain conditions and for a certain period of time. It is estimated that if all countries in the world follow the example of the United States in consuming minerals, the world will run out of zinc in six months, oil in seven years, natural gas in five years, copper ore in nine years and lead ore in four years. Therefore, it is the responsibility of all mankind to cherish various natural resources.

establishment of nature reserves

The proportion of nature reserves in the total land area is a yardstick to measure the development level of nature protection and the progress of science, technology and culture in a country.

Nature reserves refer to natural areas such as representative natural environment and ecosystem, habitats of rare animals and plants, important natural historical sites and important water sources designated by the state for the protection of natural environment and natural resources. It includes ecological protection areas, biosphere protection areas and specific natural objects protection areas; National parks, nature parks, forest parks and marine parks; No logging area, no fishing area and no hunting area; Glacier remains, hot springs, fossil groups, etc.

Nature protection includes the protection of natural environment and natural resources. Its specific contents are as follows: First, protect the ecosystems that are basically in the primitive state or less affected by human activities, such as Changbai Mountain temperate mountain ecosystem nature reserve in Jilin Province; The second is to protect and restore representative natural ecosystems destroyed by human beings, such as Xishuangbanna Nature Reserve in Yunnan; The third is to protect ecosystems with special values, such as rare animals, cultural relics and historical sites, and fossil producing areas.

Nature reserves have been established in the world for over 100 years. 1872, the United States established the world's first nature reserve-Yellowstone National Park. 1948, the international union for conservation of nature was established. Since then, various nature reserves have been established around the world. At present, Japan, the United States, Germany and Kenya account for more than 10% of the total land area.

China has designated nature reserves nationwide since 1956. By 1987, there were 48 nature reserves in China, covering an area of 230,000 square kilometers, accounting for 2.47% of the total land area. Among them, there are 30 national nature reserves. The first nature reserve in China is Guangdong Dinghushan Nature Reserve, which mainly protects special natural scenery. Among the nature reserves in China, the largest is Xinjiang Altun Mountain Nature Reserve, covering an area of 4.5 square kilometers. The first giant panda reserve is Wang Lang Nature Reserve in Sichuan. The first water source protection zone is Yunnan Songhuaba water source system protection zone; The only special geological and geomorphological reserves are five Lianchi Nature Reserves in Heilongjiang Province, which are called "Volcano Natural Museum".

Nature reserves can completely preserve the true colors of the natural environment, and are natural treasure houses of animals, plants and microbial species. They can protect, cultivate, introduce and develop natural resources, and play an important role in soil and water conservation, water source protection and ecological balance. Nature reserves are of great significance for promoting the development of production, education, medical care and scientific research. There are thousands of species in Changbai Mountain Nature Reserve in China. The Korean pine forest growing in it is like a reservoir, storing rainwater in the soil. Even if it rains continuously for two hours and the rainfall reaches 100 mm, it will not cause water loss. Because there are hundreds of natural doctors in nature reserves-beneficial birds and beneficial insects, large areas of pine, fir, poplar and birch are rarely damaged by pests.

Green barrier to protect the earth

The forest is the cleaner of nature. In terms of environmental protection, the ecological benefits of forests are far higher than the direct economic benefits. Finland produces wood worth 65.438+0.7 billion marks every year, and the ecological benefits of forests provide 5.3 billion marks. The ratio of direct value provided by American forests to ecological benefit value is 1∶9.

Forests are factories that make oxygen. According to the measurement, an acre of forest generally produces 48.7 kilograms of oxygen every day, which can meet the needs of 65 people a day. Forests can absorb harmful substances. 1 ha Cryptomeria fortunei forest can absorb 60 kilograms of sulfur dioxide per month; Ligustrum lucidum, clove, phoenix tree, weeping willow, juniper and acacia have better effects on reducing hydrogen fluoride. Forests can conserve water and soil. If 20 cm thick topsoil is washed away by rain, it will take 577,000 years for woodland, 82,000 years for grassland, 46 years for cultivated land and 18 years for bare land. This shows that the lack of forest vegetation will aggravate soil erosion. Forests can store water.

The canopy is like an open umbrella, which can intercept 10-20% rainfall. The water storage capacity of 50,000 mu of forest is equivalent to a small reservoir of 6,543.8+0,000 cubic meters. There has always been a saying in China that "planting a few trees on the mountain is equivalent to building a reservoir". Trees, like water pumps, can absorb water from the soil and spray it into the atmosphere through transpiration. An acre of Chinese fir forest can transpiration 170 tons of water in the annual growth period. At the same latitude and the same area, the amount of water evaporated by the forest is half that of the ocean. In addition, trees can also prevent wind, fix sand and reduce noise.

However, for a long time, people only thought about the utilization of forest vegetation and neglected the protection, because deforestation caused serious soil erosion. The Loess Plateau in China used to be "the peak of cypress smoke and the top of clear spring" in history, and the forest coverage rate reached 53% in the Western Zhou Dynasty. Now the forest is destroyed, the plateau is cut into pieces by running water, and the soil erosion is extremely serious. Every year, the average sediment discharged from Sanmenxia reaches 65.438+0.6 billion tons, and about 40 million tons of nitrogen, phosphorus and potassium fertilizer are taken away, which is equivalent to nearly four times the annual output of chemical fertilizers in China. The reduction of forests has led to the continuous expansion of desertified land. Now, 60,000 square kilometers of land in the world become deserts every year. According to this development speed, by the year 2000, the desertification land in the world will expand by 20%, and the cultivated land will decrease by 1/3. The reduction of forests has also worsened the climate, increased disasters and reduced agricultural output.

Therefore, on the one hand, we should plant trees and continuously expand the area of forest vegetation, on the other hand, we should protect the existing forest resources, make forests a green barrier to the earth, and play an important role in realizing a virtuous circle of natural ecology.

Protect precious wild animals

Wild animals are a kind of precious natural resources and precious wealth of human beings. Wild animals provide us with a lot of industrial raw materials such as food, medicine and leather. The development of fishery is inseparable from aquatic animals, which are an important source of protein and an animal in our life. Without the protection of beneficial birds and insects, it is difficult for agricultural production to proceed normally.

There are only dozens of kinds of poultry and livestock that provide meat and milk for human beings, but there are at least 1 10,000 kinds of animals on the earth, which provides us with resources that can be fully developed and utilized. Wild toads have become a delicacy for Chilean people because of their delicious meat. The capybara, produced in Central and South America, can be raised to the size of a pig and has become a substitute for Venezuelan people to eat beef.

Colorful wild animals are a huge natural "gene pool", which can provide a variety of natural provenances for us to cultivate new varieties. Many wild animals are also the starting point of bionics. For example, the rattlesnake missile is an infrared guided missile, inspired by the fact that rattlesnakes use thermal locators to catch prey. Some animals, such as giant pandas and Chinese alligators, are called living fossils, which is of great significance to the study of biological evolution.

Wild animals are the products of nature, which is composed of many complex ecosystems. When plants disappear, insects that feed on them will also disappear; Without insects, birds that prey on it will starve to death; The death of birds will have an impact on other animals.

Therefore, large-scale wildlife destruction will cause a series of chain reactions and have serious consequences. Nowadays, many wild animals are on the verge of extinction. Forests were destroyed, depriving them of their habitat; Environmental pollution brings them death; There is also a large number of human hunting, making many precious species on the verge of extinction. According to reports, the number of Thunderbirds in Europe has dropped sharply, with only a few dozen American egrets left, African rhinoceros on the verge of extinction, Australian platypus few left, Arabian longhorn antelope near extinction, whales surviving and Hawaiian geese greatly reduced.

Nowadays, the protection of wild animals has attracted the attention of all countries in the world. As early as 1962, the government of China promulgated the "Instructions on Active Protection and Rational Utilization of Wild Animal Resources" and established a number of nature reserves. This has played a very good role in protecting wildlife resources.