Why are wetlands called the “Kidneys of the Earth”?

Did you know that wetlands only cover 6% of the Earth's surface, but provide a living environment for 20% of the Earth's known species. They have irreplaceable ecological functions and are therefore known as the "Kidneys of the Earth."

What is a wetland

Wetlands refer to natural or artificial swamps, peatlands or water areas, shallow water areas of static or flowing water bodies, and also include waters with a depth of no more than 6 meters at low tide. Wetlands are widely distributed around the world and are ecosystems with rich biodiversity and high productivity on the earth.

(Photo source: Xinhua News Agency)

Perhaps at this point you will say: Wetlands are so widely distributed, why haven’t I seen them?

In fact, wetlands are all around us. There are many types of wetlands, such as coral reefs, mudflats, mangroves, lakes, rivers, estuaries, swamps, reservoirs, ponds and rice fields, all of which are wetlands.

The role of wetlands

Wetlands are an important, unique and multifunctional ecosystem on Earth. They play an extremely important role in the global ecological balance and are one of the most productive environments in the world.

Wetlands are natural reservoirs on land. Countless species of plants and animals depend on the water and primary productivity provided by wetlands for survival. Wetlands support a high concentration of birds, mammals, reptiles, amphibians, fish and invertebrate species. They are important storage sites for plant genetic material and breeding and wintering habitats for many rare waterfowl.

(Photo source: veer photo gallery)

Wetlands are also one of the most valuable environmental capitals of mankind. They not only have rich resources, but also have huge environmental regulation functions and ecological benefits. Various types of wetlands have played an important role in providing water resources, regulating climate, conserving water sources, diverting floods and reducing peaks, promoting siltation and land reclamation, degrading pollutants, and protecting biodiversity, providing humans with abundant production and living resources. Therefore, in addition to being the "kidney of the earth", wetlands also enjoy the reputation of "cradle of life", "bird paradise" and "climate regulator".

Wetlands in China

China's wetland area accounts for 10% of the world's wetlands, ranking first in Asia and fourth in the world. 30 wetlands, including Bird Island in Qinghai Lake, Dongting Lake in Hunan, Mai Po in Hong Kong, and Xingkai Lake in Heilongjiang Province, have been included in the list of internationally important wetlands.

(Photo source: Xinhua News Agency)

In my country, wetlands are distributed from the cold temperate zone to the tropics, from the coast to the inland, from the plains to the plateau mountains. Some areas have multiple wetland types, and some wetland types are distributed in multiple areas, forming a rich and diverse combination of wetland types. The eastern part of China is mostly river wetlands, the northeastern region has many swamp wetlands, and the western arid region has relatively few wetlands. There are many lake wetlands in the middle and lower reaches of the Yangtze River and the Qinghai-Tibet Plateau. The Qinghai-Tibet Plateau has the world's highest altitude large-scale plateau swamps and lakes, forming a unique ecological environment. The coastal areas from Hainan Island to northern Fujian are distributed with unique mangroves and artificial wetlands in subtropical and tropical areas.

(Photo source: Xinhua News Agency)

In fact, there are more than 30 unique wetlands in China, but many of them are still ignored because of their remote location and lack of fame.

The importance of protecting wetlands

Wetlands are one of the most beautiful areas on earth, but the importance of wetlands has been recognized by society only very late. Due to the expansion of urban areas, wetlands have become residential areas; the continuous large-scale reclamation and unreasonable development of wetlands have caused a sharp decrease in the area of ​​natural wetlands; the irrational use of wetland water resources and the deterioration of the water environment, blindly draining wetlands, excessive water extraction and diversion, and sewage discharge have led to the degradation of wetland functions; the predatory development and utilization of wetland wildlife resources has accelerated the decline of wetland biodiversity; the upstream areas of wetlands have suffered from severe soil erosion, and siltation has reduced the flood control and water storage capacity of wetlands.

(Photo source: veer photo gallery)

Protecting, developing and building wetland parks is conducive to mobilizing social forces to participate in wetland protection and sustainable use, and is conducive to giving full play to the ecological, economic and social benefits of wetlands, while meeting public needs and the requirements of social and economic development. Through social participation and scientific management, the goal of protecting wetland ecosystems and maintaining the continuous performance of multiple functional benefits of wetlands can be achieved. It is of great significance to improve regional ecological conditions, promote sustainable economic and social development, and achieve harmonious coexistence between man and nature.

Conclusion

Wetlands are warm, they conserve water and nourish all things; wetlands are also heavy, they settle dirt and dilute floods. As a part of nature, humans should cherish this beautiful wetland, work together to protect the "kidney of the earth", and jointly protect our home.

Editor: Sun Chenyu

Produced by: Science Popularization China

Author: Earth Story Team

Producer: China Science Expo