Why is biodiversity important? Finally someone explains it

Produced by: Science Popularization China

Produced by: Zhiyao Science

Producer: Computer Network Information Center, Chinese Academy of Sciences

Image source: Xinhua News Agency

On October 11, the 15th meeting of the Conference of the Parties to the Convention on Biological Diversity (COP15) was held in Kunming, Yunnan!

COP 15 promotional image (Photo source: China National Geographic Books)

When it comes to "biodiversity", everyone's first reaction may be: "Biodiversity means there are many types of organisms."

In fact, this explanation of its definition is not accurate. So what exactly is biodiversity? Is it really true that the more species there are, the better?

What is biodiversity?

Biodiversity refers to the overall diversity of organisms and their environment.

In other words, animals, plants, microorganisms, and even the different ecosystems they form are all part of biodiversity. A simple and cute giant panda in a nature reserve, a tiny intestinal flora in our stomach, are all part of biodiversity.

Rich and colorful natural systems (Image source: provided by the author)

Biodiversity, in addition to referring to different species of organisms, also includes the diversity of ecosystem composition. In other words, the different habitats, growth and reproduction methods of the same organism in different environments also belong to different biodiversity contents.

There is an old Chinese saying that goes, "Oranges grown in the south of the Huai River are oranges, while oranges grown in the north of the Huai River are tangerines," which describes the diversity caused by the environment.

What is the current state of global biodiversity?

It is estimated that there are currently 5 to 100 million species in the world, but only 2 million have been confirmed[2]. From this perspective, the world's biological species seem to be very numerous and rich, and the biodiversity situation should be very good.

But in fact, most of these species are small creatures such as insects. There are only more than 5,000 species of mammals that have a significant impact on the ecosystem.

Moreover, as the scope of human activities continues to expand and the impact on the ecosystem continues to grow, the rate of species extinction is gradually increasing.

Since 2006, the number of bees on Earth has begun to decline sharply, and the extinction rate of the bee species has begun to accelerate. The reduction of bees makes it difficult for plants to pollinate. If they become completely extinct, the continuation of many plant populations will also suffer a catastrophe.

Bee pollination (Photo source: veer photo library)

In Australia, 12 native butterfly species have become almost extinct. The disappearance of pollinating insects such as bees and butterflies may accelerate the extinction of other plants and animals, and eventually bring about a catastrophe to the biodiversity of the entire natural world like an avalanche.

Although the creation and extinction of species is a normal process in nature, it is estimated that the rate of man-made extinction caused by human activities is 100-1000 times that of non-man-made extinction.

The dodo originally lived carefree on the island of Mauritius, but humans discovered them and began to hunt them. The dodo became extinct because of hunting by humans in 1681. As human activities have an increasing impact on nature, the current status of biodiversity is not optimistic.

Restoration of the Dodo (Source: Veer Gallery)

Fortunately, humans have gradually realized the importance of biodiversity and have gradually done better in protecting biodiversity. Today, my country has established 2,349 nature reserves, covering 15% of the country's area, creating habitats for wildlife communities.

Why protect biodiversity?

There is a saying in the theory of evolution called "survival of the fittest". According to this, organisms that are not adapted to the environment should be eliminated. So why should we spend effort to protect endangered species that will disappear anyway? What is the significance of protecting biodiversity?

There are many aspects to consider when protecting biodiversity.

First, different kinds of organisms have different use values.

From food and medicine to industrial raw materials, from scientific research to aesthetic creation, human life is inseparable from the diversity of species. Beef is delicious, but if this is the only kind of meat left in the world, many people will quickly find it boring.

The research and development of medicinal materials or the extraction of industrial raw materials are inseparable from the magical species existing in nature. For example, artemisinin, a magical drug for treating malaria, is extracted from the plant Artemisia annua.

Artemisia annua (Source: Plants of the World Online)

Secondly, biodiversity is particularly important for maintaining ecosystem stability.

Material circulation is one of the foundations to ensure the operation of the ecosystem, and the "oxygen-carbon dioxide cycle" formed by photosynthesis and animal respiration opens up the circulation chain between the inorganic environment and organic organisms, maintaining the balance of carbon dioxide in the atmosphere.

Imagine if the number of plant species in nature were drastically reduced due to human activities, the Earth's ecosystem would become more fragile, potentially leading to the death of a large number of plants and the collapse of the ecosystem, thus bringing a catastrophe to humanity.

Only by protecting more species can we strengthen the ecosystem's resistance and better respond to various crises.

Photosynthesis (Image source: provided by the author)

Finally, human beings do not have a deep enough understanding of biology. The mechanisms of many diseases, drugs, and life activities have not yet been clearly studied.

The balance of the ecosystem is also a matter of one thing affecting the whole body. With the current level of technology, it is difficult to accurately assess the impact of the disappearance of any species. Therefore, preserving as many species as possible can prepare for future social development and technological progress. It is a good thing to be prepared for danger in times of peace.

How to protect biodiversity?

Since biodiversity is so important, how can we protect it? Some people say: let’s have as many species of organisms in the ecosystem as possible!

But in fact, blindly introducing new species may cause devastating consequences to existing ecosystems.

In the 19th century, Asian fish such as carp and grass carp were introduced to the United States to control the excessive growth of insects and aquatic plants. At that time, these species did successfully control the number of insects and aquatic plants. But decades later, the American people realized that something was wrong. The ecosystem of the Great Lakes in the United States was almost taken over by these Asian carp!

Asian carp have taken over the Great Lakes (Image source: provided by the author)

"It is easier to invite a god than to send him away." When Asian carp were introduced, they only needed to be thrown into the river to achieve the goal of "controlling insects with fish." However, it would be extremely difficult to control the subsequent rampant Asian carp.

Since then, the US government has tried to control the number of Asian carp through toxins, killing, electric fences and other methods, spending a total of $100 million, but the effect is not very ideal. In 2012, the "Mississippi River-Yangtze River" Green Partnership Project was added to the framework of the China-US Green Partnership. Part of this project is to introduce China's research results and management experience on freshwater fish to the United States to help them control these Asian carp.

In addition to Asian carp, water hyacinth, white moth, golden apple snail, etc. are all very famous examples of invasive species. These newly introduced species not only grow fast and have strong reproductive capacity, but also have amazing environmental adaptability. In the new ecological environment, they lack natural enemies and quickly become the local "ecological tyrants", which in turn greatly damages the local biodiversity, which is not worth the loss.

Therefore, the protection of biodiversity must follow the principle of "adapting measures to local conditions". For endangered species, corresponding nature reserves should be built in their activity areas, using the most suitable environment to protect the most suitable animals. For example, the 67 giant panda nature reserves established in Sichuan, Shaanxi and Gansu are bamboo forest paradises "tailor-made" for pandas.

Giant pandas living in their habitat (Image source: provided by the author)

Image source: Wujiao Giant Panda Nature Reserve

As for the more fragile local ecosystems, we must strengthen protection efforts and try to avoid foreign invasion and human destruction. It is strictly forbidden to bring various living things when passing through customs, which is also out of consideration for the protection of local ecosystems and biodiversity. In the process of protecting biodiversity, we must remember: "The right one is the best."

The best way to protect the environment is to build a natural and harmonious ecosystem and avoid monopoly.

References:

[1] Li Wenhua, Zhao Jingzhu. Review and Prospect of Ecological Research[M]. Meteorological Press, 2004.

[2] Tian Min, Wang Yuxin. Current status and development trend of biodiversity conservation[J]. Hebei Forestry and Fruit Research, 2008, 23(04): 407-409.