What is the ecological function of wetland?

As an object between land and water, wetland has both land and water characteristics, is one of the most biodiversity ecological landscapes in nature, and is also one of the environments on which human society depends for survival and development, with special ecological functions and valuable natural resource values.

First of all, it can store water and regulate flood and replenish groundwater. In rainy season or flood season, the surplus water is stored by the wetland (like a sponge), which directly reduces the flood pressure downstream. Then slowly release it in a few days, weeks or even months to replenish rivers or groundwater, effectively alleviating the problem of water shortage or cut-off of rivers in dry season.

The second is to adjust the climate. Through evaporation, wetlands can continuously transport a lot of water to the atmosphere, adjust the regional climate, and reduce the frequency and harm of drought. Lhasa has a dry climate. There are so many lakes and wetlands. The evaporation of water can make the air in the city moist. Without this wetland, the climate in Lhasa would be drier. Experts appeal that there is a large lake and swamp next to Lhasa, a plateau city, and it must be protected, which is not only beneficial to the life of urban citizens, but also to the health of tourists.

Third, it can purify natural water. When the water flows through the wetland, the flow velocity slows down, which is helpful to the precipitation of pollutants. In particular, some wetland plants can effectively absorb toxic, harmful and mineralized substances and purify water bodies. Therefore, using constructed wetland to purify sewage has become a simple, economical and practical primary sewage treatment technology.

Fourth, control soil erosion and protect the coastline. Wetland and its vegetation can stabilize the base, reduce the impact of waves and seawater, and effectively prevent the erosion of coastline, estuary and river bank.

Fifth, protect biodiversity. The special environment of wetlands provides abundant food sources for wild animals, and also creates good conditions for avoiding enemies. It is a good place for a large number of rare and endangered birds, amphibians, reptiles, fish, mammals and high and low plants to grow and inhabit. Wetland protection has become one of the four major areas of international biodiversity protection.

If forests are compared to the lungs of the earth, wetlands are often called kidney of the earth, natural reservoirs and natural species banks. Protecting wetlands has become the focus of international environmental protection and an important ecological measure for flood control in various countries. Wetlands have also become the target of ecotourism for some tourists.