The maple leaves this year are not red enough, but these "coast guards" are really red...

Mangroves are woody plant communities that grow in the intertidal zones of tropical and subtropical coasts. At low tide, they stand on the seashore, forming a "coastal forest" with tangled roots; at high tide, they are submerged by the sea, with only the crowns above the water, forming a "sea forest";

Sometimes when the tide is too strong, they will be completely submerged in the sea, becoming an "underwater forest". The pictures we saw earlier are of Kandelia obovata Sheue et al., Rhizophora stylosa Griff. and Sonneratia caseolaris (L.) Engl., which are actually all mangrove plants.

Why are mangroves called mangroves?

Why are mangroves called "red" forests when they don't look red? It turns out that the main plants that make up mangroves are Rhizophora plants, and the barks of Rhizophora plants are rich in tannic acid . This substance is colorless and transparent, and it easily oxidizes and turns red when exposed to air. This is the so-called "red inside, not red outside", and mangroves got their name from this.

What is the function of mangroves?

Mangroves are a happy home for many water birds and marine animals such as fish, shrimps, crabs, and shells to avoid enemies, reproduce, and grow. They can also purify coastal water quality and absorb and fix carbon . Reports indicate that the carbon storage capacity of native tropical mangroves is 6 times that of the Amazon rainforest of the same area.

Are there other benefits for humans?

For humans, the most direct role of mangroves is to protect embankments and banks , and to prevent wind and waves . In the 2004 Indian Ocean tsunami, about 172 households in a fishing village in Tamil Nadu, India, survived because of the dense mangroves there. In the southeastern coastal areas of China, mangroves play an important role in disaster prevention and reduction during the more than ten typhoons each year.

In addition, mangroves have functions such as promoting siltation and land creation, preventing red tides, and are an almost "all-round" wetland ecosystem.

What problems are mangroves facing now?

There are about 38 species of mangroves in China. They are mainly distributed in the coastal areas of Guangxi, Guangdong, Hainan and other provinces. Historically, the area of ​​mangroves in China once reached 250,000 hectares. In the 1950s, there were only about 50,000 hectares left. By 2001, it had dropped to 22,000 hectares. The reduction in the area of ​​mangroves has led to the loss of coastal bird habitats and fishery resources, and has also exacerbated coastal red tide disasters and coastal erosion, becoming one of the important reasons for the degradation of coastal ecosystems.

How can we protect mangroves?

Faced with the precarious status of the mangrove ecosystem, people often call it the "panda of the ecosystem" . At present, China's protection of mangroves mainly focuses on management and planting.
In recent years, proposals on strengthening the protection of mangroves have been put forward at the annual National People's Congress and the Chinese People's Political Consultative Conference. Regulations such as the "Regulations on the Protection and Utilization of Coastlines" and the "Regulations on the Control of Reclamation" all require strict protection of natural coastlines and the repair and restoration of damaged coastlines.

Mangrove afforestation is a complex scientific system from site selection, afforestation to later care.

Hainan Dongzhaigang National Nature Reserve is the largest mangrove nature reserve in China so far, with the most tree species, the best conservation and the richest resources. Biological protection and ecotourism go hand in hand, legislative protection and strict supervision are given equal weight, and environmental improvement and ecological restoration are carried out simultaneously. A series of measures have begun to show results in mangrove protection.