Ecological function of wetland

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 the river or seep down to replenish groundwater, effectively alleviating the problem of water shortage or cut-off of rivers in dry season.

Secondly, it 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 and 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 are a lot of lakes and swamps beside Lhasa, a plateau city, which must be protected, which is not only beneficial to the life of urban citizens, but also beneficial to them.

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 quality. Therefore, using constructed wetland to purify sewage has become a simple, economical and practical primary sewage treatment technology.

Fourth, controlling soil erosion and protecting coastlines, wetlands and their vegetation can stabilize the base, reduce the impact of waves and seawater, and effectively prevent the erosion of coastlines, estuaries and banks.

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 a hot spot of international environmental protection and an important ecological measure for flood control in various countries, and wetlands have also become the target of ecotourism for some tourists.