Since the time of the first seafarers, only 5% of the waters of the ocean have been studied. In addition to the huge variety of representatives of the animal world, lush vegetation is represented in the ocean. Which in itself is surprising, because the average depth is 4 kilometers, and sunlight hardly penetrates through such a thickness. Therefore, deep plants are a kind of unique form of life. But not only deep-sea flora is of interest.
Big Seaweed
Sargassum or Sargassum is the largest algae with characteristic spherical bubbly floats. Vegetation varies in color from brown olive to yellowish olive.
Algae grows on rocks and any solid objects that are in its path. Algae fixation is carried out with the help of statutes. Above is one or more stems (up to 10 centimeters long) with sharp leaves.
The maximum length of the whole plant is 10 meters. In addition to leaflets and stems, the plant has spherical bubbles and reproductive organs up to 1 cm in length with a diameter of notover 2 mm.
Spherical bubbles are spheres containing gas. Their diameter is about 3 mm. May be in clusters or single.
This genus of brown algae includes about 150 species.
There is a version that the Sargasso are the coastal belt of the lost Atlantis. Since that time, they have been able not only to survive, but also to adapt to modern living conditions.
Where does it grow?
Sargassum grows at a depth of 2 to 3 meters, but it all depends on the region where it lives.
The plant is found in northern British Columbia and southern California. Here it grows at a depth of no more than 2 meters and in places where shallow water and tides are very low and rare. Although in the same California there are algae that grow at a depth of 8 meters. In these waters, the seaweed grows from 3 to 10 meters in length.
In the waters of France, the plant lives at a depth of 25 meters, and on the coast of England it occurs at a depth of 6 to 8 meters. Here it can also be seen on the shore attached to other algae and oyster shells. In these waters, the average plant length is 3 to 4 meters.
Small Sargassum algae are found on the Japanese coast - no more than 2 meters in length.
Living conditions
The main condition under which this algae will grow is the salinity of the water from 7 to 34 ppm. The water temperature should be between + 10 and +30 °C. Although a number of studies have shown that the lush vegetationis directly related to the temperature of the water, and the higher it is, the better the algae grows. It is best when the water temperature is above + 25 ° C. Photosynthesis occurs faster at temperatures from + 15 to +20 ° С, and young shoots develop better at + 20 ° С.
Reproduction
Sargasso algae have female and male reproductive organs. They are located almost at the edges of the outer branches in the middle of the plant.
On average, a plant 2 meters high can produce up to one billion embryos. Attachment of embryos occurs in some minutes after the appearance.
In some cases, embryos cling to the surfaces of surrounding objects even before the moment when the plant itself has not yet fully grown and the branches have not attached to the trunk.
Embryos can swim freely for up to three months, forming colonies in new places.
An interesting fact: Sargassum algae, which grows in the Sargasso Sea, do not have genitals and even organs designed to attach to other objects. Here they form a formless mass, constantly floating on the surface.
Rivalry in the outside world
What is Sargassum seaweed? It is believed that this plant displaces many other algae from their usual "familiar" places. This happens due to the darkening of the habitats of other algae. A striking example is the coast of Great Britain, where Sargassum has replaced kelp, fucus and cystoseira. In France, algae "beat" zostera andSaccharina. A similar situation is observed off the coast of British Columbia, where Sargassum is now growing instead of Zostera.
A plant of this species often grows around screws and jetties. If the layer breaks away from the habitat, then it forms a whole mat that swims in search of a new place.
Algae cause great harm to fishermen when they grow around nets.
On the coast of the south of England, the authorities are actively working to combat this vegetation. It is harvested by hand, with tractors, special harrows are built and fought with other methods. In just three years (from 1973 to 1976), about 48 tons of algae were destroyed.
In most countries where this problem is, cleaning work is carried out annually, but no one has yet succeeded in completely eradicating the plant. Herbicides, which at one time destroyed algae, do not act selectively, therefore, they also kill other representatives of the aquatic world, that is, this method of control is not effective and even harmful.
Aquatic haven
But algae are not only harmful to the environment. Sargassum is home to 9 fungi, 52 other algae and 80 ocean wildlife.
Some species literally live on these plants, such as tubeworms and some types of fungi.
The birthplace of the plant and how quickly it spread around the world
When describing Sargassum algae, it is impossible not to mention thatThis plant is native to Japan, Korea and China. Today, this species is found almost all over the world: in North America, Western Europe, Alaska, Mexico, Portugal, Norway, the Mediterranean Sea, the Far East in Russia.
In the middle of the 20th century, the plant came to North America. Supposed to be along with oysters from Japan. Already in 1944, the alga was found off the coast of British Columbia, a year later - in California. It was first seen in the UK and Mexico in 1973, and in Hawaii in 1999.
According to the most conservative estimates, the average annual spread rate of Sargassum is 60 kilometers, in the Atlantic - about 7 kilometers, and near England - 30 kilometers, because it is a little colder there.
Plant benefits
Sargassum algae are often pictured together with other representatives of the aquatic world, because they are the habitat and food of many animals and plants. And the turtles use them as a mat, which is very easy to move on.
On the shores where seaweed appears, crabs and insects feed on it. Also, the plant is an excellent food base for other representatives of the underwater world.
Besides, it is in the thickets of sargassum that you can catch the largest fish. The plant also has pharmaceutical potential and can serve as a biofuel. In agricultural work, algae is used as a potash fertilizer.
Flocculants, which are formed in the plant, allow you to purify wastewater from organic pollutantselements. They can collect heavy metals, nickel and chlorophenolic compounds.
