Mangroves are one of the planet's most stunning natural wonders, and they are widely distributed along the coastlines of tropical and subtropical regions, providing a rich ecological service to humans and numerous creatures.
Mangrove is a group of woody plants that grow in the intertidal zone of tropical and subtropical coasts, and is not a single species. As for why it is called mangrove, it is mainly because between the ebb and flow of the tide, these flooded woody plant communities are rich in "tannins", and the sap will quickly oxidize and turn red when the bark is scraped and comes into contact with the air, so it is called "mangrove". Mangroves are a special type of forest in the coastal zone, and unlike other vegetation forests, mangroves are mainly found in coastal areas and grow in tidal and humid saline zones.
Usually, mangroves are mainly divided into two categories: true mangroves and semi-mangroves, which do not refer to the authenticity of trees, but are distinguished according to their growth environment.
Hainan Lingshui New Village Mangrove Reserve.
Mangrove forests form an oasis on the shore, and mangroves have gradually evolved many unique survival wisdom to resist environmental challenges such as wave impact, high salinity, reproduction and pollution, making them play a huge role in promoting siltation and beach protection, preventing wind and waves, and purifying seawater, and become a veritable "coastal guardian".
Special reproduction mechanism – viviparity mechanism
Speaking of "viviparity", it is too common for mammals, but it is indeed a wonderful existence for plants. Unlike other plants that reproduce by seeds, mangrove offspring begin to develop on the mother tree, and their fruits remain on the mother tree after maturity, and quickly grow 20~30 cm radicle, which is then shed by the mother tree, inserted into the mudflat, and quickly germinates and roots into new individuals. The viviparity mechanism of mangroves allows them to protect their babies on the trunk of the mother tree, providing them with the right environment and nutrients for their smooth growth. This unique mode of reproduction allows mangroves to sustain their families while challenging the harsh coastal environment.
Special growth wisdom - special root system
In order to "gain a foothold" in the muddy environment, mangroves are constantly "developing" criss-crossing root systems with different functions in the coastal environment where the sea is rough and the soil is muddy, soft and anaerobic. In order to maintain balance under the impact of tides and waves, pillar roots and tabular roots dig deep into the silt to create a stable "growth support" for the mangroves. For example, a mangrove tree grows a curvature of pillar roots around its trunk near the surface of the water, digging deep into the silt.
To adapt to periodic hypoxic environments, mangroves have evolved respiratory roots, which grow upwards and expose the ground. The respiratory root acts as the aeration, storage and ventilation organ of the mangrove, allowing it to absorb air in muddy and saltwater environments, and becomes a wonderful weapon to maintain the normal life of the mangrove.
Special Adaptability – Salt Tolerance Mechanism
Mangroves generally grow in intertidal environments, and in order to thrive in high-salinity environments, they have a special survival mechanism – they can handle high salinity and salinity in the soil. The root system of mangroves has the function of screening and draining salt, which can selectively absorb water and remove excess salt. This special structure allows mangroves to adapt quickly and maintain normal growth in a salt-flooded environment.
Secondly, mangroves also possess an ionic regulation mechanism. When the roots absorb the salt, the mangrove concentrates the salt in the roots and excretes the excess salt through ionic regulation. This mechanism allows mangroves to achieve a balance of salt ions within the body and maintain the normal function of cells.
Organisms in mangrove ecosystems.
The role of mangroves
The seemingly ordinary mangrove forest not only has a beautiful scenery, but also provides a large number of ecological services, such as carbon cycle in nature, biodiversity conservation, coastal siltation and beach protection, wind and wave control, sea purification, climate regulation, environmental beautification and many other aspects.
First, the solid "growth scaffolds" formed by mangrove forests are the protective barrier foundation of coastal defense lines, which can absorb most of the impact of typhoons and storms, thereby mitigating the negative impacts of storms on land and human communities. The rooting process of mangrove growth helps to promote siltation and stabilize the coastline.
Secondly, mangroves are a diverse ecosystem, an ideal habitat for animals, and a rich source of food for animals. Mangrove forests are important breeding grounds for birds, fish, crabs, shellfish and other marine life, plankton and benthic organisms depend on the organic matter formed by mangrove leaves and plant residues falling into the water, small shrimp, crabs and clams cling to the roots and supports of mangroves in search of food and refuge, herons, seabirds and cranes often nest and breed in mangroves, and some migratory birds also find habitat and replenish energy in mangroves.
Mangroves are also known as the "green lungs of the ocean" and their presence is essential for the health and ecological balance of the ocean. Mangroves have excellent carbon storage and sequestration capabilities, converting carbon dioxide into organic matter through photosynthesis and preserving it in trees and soil, which helps reduce greenhouse gas emissions and mitigate the effects of global climate change to some extent. In addition, mangroves can filter water quality and purify bays, and their root network can filter suspended solids and sediments, purifying seawater of organic pollutants and chemicals.
In addition to their ecological roles, mangroves also have important economic value. Mangrove forests provide abundant resources for local residents, such as timber, food, and medicinal plants. Many coastal communities rely on mangroves for fisheries, tourism and sustainable development projects, generating economic income and employment opportunities.
Geologists conduct field surveys of mangrove ecosystems.
Conservation of mangrove forests
Mangrove forests, this wonderful natural treasure trove located along the coastline, play an irreplaceable role, not only providing unique and beautiful landscapes, but also having a vital impact on ecosystems and coastal environments. However, mangrove forests also face many challenges, such as land reclamation, pond farming, disorderly sand dredging, domestic wastewater, solid waste pollution, and marine engineering construction.
In order to protect mangrove ecosystems, positive actions are being taken around the world, including the establishment of nature reserves, education and education, monitoring and scientific research, and the promotion of sustainable development practices. At present, remarkable achievements have been made in the ecological protection and restoration of mangrove forests in mainland China, with the establishment of relevant mangrove reserves, the continuous introduction of regulations, policies and standards, and the promotion of mangrove ecological regional restoration by continuously strengthening the overall planning of sea and land.
It's hard, but it's done. Because of this, we hope to raise public awareness of the importance of mangrove forests through continuous science popularization, and encourage more people to protect this natural miracle, so that this unique and vibrant ecosystem can be effectively protected, effectively improve ecological quality, increase the supply capacity of ecosystem services, and ensure that these special and important ecosystems can thrive sustainably.
(Author's Affiliation: Haikou Marine Geological Survey Center, China Geological Survey)