Mangrove trees - a unique creation of nature

Mangrove trees are evergreen deciduous plants, settled on tropical and subtropical coasts and adapted to life in conditions of constant ebb and flow. They grow up to 15 meters and have quaint types of roots: stilted (raising the tree above the water) and respiratory (pneumatophores), sticking out of the soil like straws, and absorbing oxygen.

Few plants would survive in salt water, but this does not apply to mangroves. They developed filtering mechanisms. Water, sucked up by their roots, contains less than 0.1% salt. The remaining salt is excreted by leaves through special leaf glands, forming white crystals on the surface.

The soil on which mangrove trees grow is always saturated with water, oxygen in it is not enough. Under these conditions anaerobic bacteria secrete nitrogen, phosphates, iron, methane, sulfides, etc., creating a specific smell of trees. The lacking oxygen roots, as was said, absorb from the air, and nutrients - from the soil.

The leaves of these plants are hard, leathery, juicy, bright green. Given the salinity of the soil and the lack of fresh water, they have adapted to a limited loss of moisture. Leaves can regulate the degree of openness of stomata that perform gas exchange during photosynthesis, and rotate, avoiding hot sunlight.

Mangrove trees grow in belts, in each of which certain species predominate. This is due to the frequency and duration of flooding, the nature of the substrate (sandy or silty), the ratio of sea and fresh water (in the mouths of rivers). The foremost line is occupied by the rhizophores with blood-red wood, the color of which is determined by the high content of tannin. This species is under water about 40% of the time. They are followed by avicenia, lagularia, etc.

How untypical is the mangrove tree itself, and the fruits (seeds) of it are unusual. They are covered with air-borne fabric, due to which they can swim for a certain time, changing their density if necessary. Many mangroves are "viviparous". Their seeds, not separated from the tree, germinate. The stalk moves either inside the fetus, or through the fetus outward. By the time of separation, he is ready to eat independently through photosynthesis.

Disconnected from the tree (as a rule, at low tide), the sprout drops and quickly fixes in the soil. Or carried away by water, perhaps for a decent distance. He is so tenacious that he can wait until the year to take a favorable moment to take root.

Mangroves serve as a refuge and habitat for many organisms. Algae, oysters, barnacles, sponges, bryozoans need something to attach to when filtering food. Numerous roots are great for this. Tropical fish, arthropods, snakes live in the water near the root systems. Hummingbirds, frigates, parrots, seagulls and other birds settled in the branches of the trees.

Mangrove trees, quickly forming thickets, protect the shore from erosion by sea waves. They, advancing on the sea, win from him new plots. Densely intertwined roots keep the applied silt, contributing to the drying of the soil. The local population uses the conquered lands, creating plantations of coconut palms, citrus and other crops.