Interesting facts about the Black and Azov seas. Why does the sea glow? Azov sea at night

At night, there are phyto- and zooplankton on our coast - everything is mixed in shallow water. And most plankers are capable of glowing in the dark. This is one of the most joyful - for us - of their properties. Chemically, the reaction of the glow of marine organisms is exactly the same as that of the firefly beetles that we admire on warm summer nights on the shore. Substance - luciferin (light carrier - Greek) is oxidized by oxygen under the action of an enzyme luciferase ... Most chemical reactions generate heat, and this one produces one quantum of green light.

From July to the end of September. But the best time is from the beginning of August to the beginning of September - the first weeks of the summer-autumn development of plankton.

Already approaching the dark water, we see that a weak surf shakes pieces of greenish light on the sand - feel them with your hands - they are slippery, they melt on your fingers. These waves washed up the ctenophores, they have already been smashed against the sand, but they continue to glow. Shake them off your hands - and the light will remain on your palms - even smaller pieces of the delicate bodies of sea creatures stuck, remained on your skin. If we walk along the edge of the surf, we will find small, constantly glowing points on the sand - we will pick them up and try to examine. These are amphipods, sea fleas - but already dead, they do not jump like the ones we chased during the day. These crustaceans have already begun to eat, decompose, bacteria that always glow - just like rotten ones glow. Why do plankton organisms glow? Let's wait until nightfall and answer this question ourselves. The darker the night, the better - flashes of living light in the sea will become more noticeable. And, of course, the sea must be calm - otherwise we will not see anything. In general, the night should be quiet, dark and warm. There are many of them on our shore - from the beginning and in the night forest. Do not be alarmed - admire, this is also life. The amphipods have many microscopic spines on their shells - we've already seen them - these spines will allow you to attach a luminous badge to your shirt - just press the crustacean to the fabric.

We will enter the dark transparent water from the familiar beach - by touch. On a summer night, the sea is warmer than the air above it, you can swim without feeling the water - they usually say about this - like fresh milk! - but night is night - and, perhaps, it is worth reminding one more about caution - you should not swim where you cannot get to the bottom.

Let's walk slowly, without splashes, from the shore and look at our feet. And the legs glow! These are tireless plankters - mobile algae, crustaceans - collide with our skin and flash with emerald light, there are so many of them that the bodies of people moving in the water become emerald. When there is really a lot of plankton, one can observe a striking sight - a luminous man floating on the ground. He dives - and shines brightly under the water, and leaves behind a sparkling trail.

Rarely, but - there is such luck - it is possible to see the games of dolphins blazing with green fire! And if you go out to sea on a boat at such a time, the oars seem to be burning - and with each stroke they break off and remain behind, whirling and wriggling, tongues of green flame.

Such an even, strong glow, in which individual flares are not visible, is caused by planktonic dinoflagellates - there are most of them in warm water. Diatoms cannot glow. Any movement in the water causes radiance and flashes. A radiance is many small flashes of microalgae merging into a single glow - there are so many of them. And some bright green lights are flashes of irritated plankton crustaceans. Sprinkle with water - green sparks will fly into the air - it is you, along with the drops, thrown into the air many tiny crustaceans. This is probably the only - and wonderful - way to see, without a microscope, life - in every drop of sea water.

If something bright and large caught fire next to you in the water - this is a comb jelly - the largest luminous animal in the Black Sea. You can try to scoop it with a boat of palms - consider its radiance.

Not only planktonic microorganisms glow, but also many bottom ones: try to dive on a rocky bottom and rub any smooth surface - it will glow; lift a stone from the bottom, rub it - it will still glow when you emerge and lift it above the water. If there were no waves over the sandy bottom for a long time and people did not swim, even on the surface of loose soil a film of micro-life is formed that can glow - then, passing along such a bottom, you will leave emerald tracks.

We have already realized that plankters do not glow all the time, but when irritated - hitting an obstacle, strong movement of water. Such signals for a copepod or dinophytic algae are a sign of a possible approach of a predator, or even a collision with it. The flash should scare off the aggressor. How can such a little spark scare someone? But compare the sizes! People, usually, are frightened by an unexpectedly lit comb jelly - and in fact it is just something - with an apple the size. For a small planktivorous fish - sprat, atherinka - a flash of green fire from the oytona crustacean can be a reason for flight. And an outbreak of dinophytic algae, in turn, can frighten off copepod cancer or worm larva. So the glow of plankton, which delights us so much on summer nights, is an active protection of weak plankters from gluttonous plankton-feeders.

There are rare cases of constant luminescence of planktonic algae - during a powerful flowering of noctiluca, or other dinophytic algae. The density of algae during such a powerful development of phytoplankton - millions of cells per liter of water - is such that individual collisions, individual flashes of light, simply merge into a constant glow.

Some marine organisms have light signals that are not intended to scare away, but, on the contrary, to attract someone - to eat that someone, or, if it is an individual of the opposite sex, to mate with it.

Deep-sea angler fish hang luminous organs in front of the open mouth, and the prey fish, swimming towards the light, finds itself in the angler's teeth. In the Black Sea, from the anglerfish family, one occasionally meets - the European anglerfish, or monkfish - a fish of a completely unusual species, but this species, although there is a fishing rod with a bait suspended over its wide mouth, it does not glow. It rarely appears off our coast - sometimes it gets into trawl nets.

Monkfish - alas, does not glow.

The fact that there are no glowing angler fish in the Black Sea is natural. For a successful hunt, they need complete darkness - these are the fish of the depths. In our sea, deeper than 150-200 meters, in the water there is no oxygen necessary for breathing, but there is poisonous hydrogen sulfide; fish cannot live there.

A wonderful light appears in the sea in those places and at the time when some species of planktonic polychaete worms mate. Unfortunately, our platineres and glycera, which we have just reviewed, do not glow. But the usual Atlantic nereis once a year arranges a fantastic light show in the waters of the Gulf Stream. On the night of the first summer new moon, the entire population of the island of Bermuda gathers on footbridges through the narrow straits that divide this island, located on the very rapids of the Gulf Stream. The only night of mating of the sea worms of the year, a local Bermuda festival - and I was lucky enough to be there at that time. Standing on the bridge over one of the island channels and peering into the black water, you finally notice the first, glowing with a bright, white-green light, wriggling worm as long as a finger, as thick as a match. It is not without reason that the Gulf Stream was called a river in the ocean - the speed of the current is 4 km / h, at such a speed we are walking. And now the current brings new nereis, after half an hour - the water turns into a boiling, shining, white-green stream - the worms float, spewing out glowing clouds of caviar and seed that mix before our eyes, these are fountains of light, this is literally a celebration of the birth of a new life accompanied by fireworks! You go down to the shore, catch the nereis, and the palm becomes covered with a glowing liquid ...

The glow of the Nereis, in addition to attracting mating partners, also plays a frightening role: in the sea there are many invertebrates and fish that can eat both worms and their eggs, but the bright light of the mass of Nereis, their eggs and seeds, will undoubtedly scare them away.

This story, of course, is not Black Sea, it is simply - about one of the wonders of marine life, most of which await you ahead. And the Black Sea is a very good sea for the first steps on this path.

By the way, the story of the Gulf Stream glowing from worms ended with a general laughter of all the biologists who worked at the Bermuda biological station at that time. That evening, the whole company from the biological station went to look at the mating of the Nereis. And one Japanese did not go - he said that he had already seen such a phenomenon. We returned late at night, joyful, lively, found and shoved the sleepy Japanese biologist, began to tell him ... He stopped us, and silently led us - it turned out that it was to the toilet. Fresh water in Bermuda is sorely lacking, and to flush toilets, water is pumped into the tanks directly from the sea. The Japanese turned out the light in the toilet, pressed the flush ... Streams of glowing, sparkling water poured into the toilet, illuminating the cramped room.

The Black Sea is a reservoir of contrasts, stories and legends. Like any huge water resource, it has hundreds of secrets. Especially interesting is the Black Sea at the junction with the Azov Sea - there you can appreciate the beauty of their differences and scale. If the Azov Sea looks more like a huge lake with a shallow depth, then the Black Sea is a real abyss. An ominous, beautiful and exciting abyss.

Paleontologists believe that in the Black Sea region since the formation of the Earth, there were salt water bodies: the Pontic, and then the Meotic Sea. In other periods, the region dried up, and freshwater springs-lakes were formed here. The sea acquired its modern boundaries, depth and type of water a little more than 8000 years ago. The reason for these changes was the devastating earthquake that formed the Bosphorus. Due to him, the Mediterranean Sea was connected with a water source nearby and began to give water to the "newborn".

The area of \u200b\u200bthe Black Sea is more than 422 square kilometers. Its length is 580 km from north to south, while the maximum depth is 2210 m. The reservoir connects southern Europe and Asia Minor.

Facts, mysteries and wonders of the Black Sea

More than one long story or legend can be told about the Black Sea. Here are just 15 small but interesting facts about him:

1. According to an ancient legend, Jason set out on a journey across the Black Sea with the Argonauts in search of the Golden Fleece. Their path ran through land and water to Colchis.
2. The first mentions of a sea source are found in documents of the 5th century BC, they are associated with the expansion of the lands of an ancient civilization.

Black Sea, view from space

1. Only the Black Sea has many names that are still used by different peoples and countries. Some names have disappeared over time. The ancient Greeks, for example, called it the Inhospitable Sea, or Pont Aksinsky. It was renamed into Hospitable, because the Greeks mastered the shores and found them attractive for winemaking, agriculture, and trade. In ancient Greek, the name began to sound Pontus Euxinian. Much later, during the time of Ancient Rus, the sea was called Scythian, somewhat less often - Russian. Other names are mentioned in historical documents found in European countries and in Asia. So, it corresponds to: Temarun, Holy Sea, Ocean, Akhshaena, Blue Sea, Cimmerian, Tauride. There is no exact information why it began to be called Black. Some historians believe that it is called so because of the color of the designation. Previously, the North was designated black, and this sea belonged to it. The second theory indicates that the sea got its name from the large amount of hydrogen sulfide in the water. If any metal got to the bottom, it turned black. However, thanks to this same hydrogen sulphide, sunken ships at the bottom remain several times longer than in the waters of other seas.
2. There are only 2500 species of animals in the waters, perhaps this is due to the peculiarities of their composition. Usually, 2-3 times more representatives live in the seas. In the Mediterranean - 9000.
3. The same hydrogen sulfide is of no less importance in a small number of inhabitants. Its concentration at a depth of more than 200 meters is so great that not a single living creature is able to survive there.
4. In August, at night, the waters of the sea begin to glow due to the migration of plankton populations, which phosphoresce.

Glowing plankton in the Black Sea

1. Unlike many seas and oceans, the name of the Black in different countries has different inscriptions and pronunciation.
2. Due to its young age, the Black Sea may increase in size. The same goes for the mountains around it. You can also notice this in the ancient cities of Crimea, which go under water for tens of meters. Oceanologists believe that every 100 years, the size of the reservoir increases by an average of 20 cm.
3. Sea dragon - the most predatory and deadly fish that lives in the Black Sea waters. Its thorns contain poison that can kill an adult.
4. The seal is a creature of a cold climate, but it finds refuge in the waters of the Black Sea.
5. The main biomass is represented by jellyfish - only 10% is allocated to other creatures.
6. The Black Sea has one large peninsula - Crimea - and only 10 islands. Compared with the Caribbean or Mediterranean, this number is ten times less.
7. The Black Sea is a source of oil and gas. But they lie so deep that no country has yet reached production.
8. Far from the coast, the sea surface is cut by huge eddies, the wavelength of which reaches 400 km.
9. In winter, the waters of the sea freeze only partially; there is a glacier area near Odessa. Byzantine documents indicate that in 401 and 762 BC, the shackles of ice completely covered the sea surface.

The Black Sea has sheltered thousands of resorts and sanatoriums on its shores, which are visited by millions of tourists every year. However, few people think about how much power and danger lies in these hospitable waters.

This magnificent natural phenomenon is called "bioluminescence". It exists in many places in the world by the sea or ocean, and manifests itself in different ways. Sometimes it seems that small stars twinkle under the water, at other times the special northern lights spread out on the water surface delight. This spectacle is best enjoyed in March, August and September.

A bit of history

For centuries, the glow of the seas and oceans remained a mystery. According to one of the versions, scientists attributed it to the presence of phosphorus in water and electrical discharges that occur when salt and water molecules rub against each other. According to another version, in this way, the ocean at night gives the Sun the energy that it accumulated during the day. The real answer was found in 1753 - then the naturalist Becker examined drops of sea water through a magnifying glass. His magnifying glass spotted tiny, unicellular organisms, about 2 mm in diameter. Interestingly, they reacted to any mechanical or chemical irritation with flashes of light. These "water fireflies" were called night lights. Now the fact that it is phytoplankton that is responsible for the "illumination" of the night sea or ocean during its mass reproduction is already undeniable.

The sparkling squid Watasenia scintillans live here. At the beginning of spring, they have a breeding season every year, and then thousands of fry rise to the water surface in search of a partner (or better a few). The bright blue light helps the squid to attract a mate for mating, and gives tourists an unforgettable and truly fabulous sight.

Amazing lights have been recorded on the Vaadhoo Islands. Thanks to bioluminescent dinoflagellates, it seems that the local coast is completely drowned in the starry sky.

In San Diego, the "water glow" does not occur every year. To be honest, scientists still don't know how to predict when they will occur. But if this event does occur, it is as if with a wave of a magic wand some invisible wizard paints the sea surface with blue phosphoric paints. If you are lucky enough to visit the local beaches, be sure to visit them at night. Who knows, what if you are lucky enough to plunge into a fairy tale for a moment?

Once upon a time strange "blue tears" were seen on the waters here, which caused a great commotion around Mazu. Scientists from the National Taiwan Ocean University spent four months of research, taking water samples daily. As a result, they found the culprit of the mysterious glow - it was the aforementioned "night light". Research is still ongoing to find other organisms that make their "shimmering contribution" to the blue ocean waters.

Warm summer months in Navarra Beach are especially popular. Still would! After all, tourists are offered a very unconventional entertainment - a night kayak adventure, and we think you already guessed what it is special about?

One of the Hypsledna Lakes, located in Australia, beckons tourists with an incredible picture that can only be seen here - at night the water glows like a large neon lamp. Such a phenomenon as bioluminescence is not uncommon in itself, and usually the activity of microorganisms called Noctiluca scintillans is the cause of its appearance.

Colonies of these representatives of the simplest organisms accumulate in large numbers in warm waters, and then the water surface begins to glow.

However, the glow on Lake Gipsend is unique, as it was the result of the accumulation of algae in the water. This type of them is one of the few that gives the water a neon glow. In many cases, science has not yet become aware of the functions of bioluminescence in the life of organisms. And it doesn't matter for tourists at all, they just enjoy the beauty.

By the way, the lake gained popularity thanks to the inveterate traveler Phil Hart, who took a whole series of photos with this unusual phenomenon. In order to photograph the bioluminescence, Phil set the resolution of the camera to maximum and threw stones and sand into the water.

Glow of the sea

The glow of the sea has long remained one of the magical mysteries of the ocean. An explanation for this phenomenon has been sought for centuries. It was believed that the glow was caused by the phosphorus contained in the water, or by the electrical charges that arise from the friction of water and salt molecules. It was even assumed that at night the ocean returns the energy of the sun. And only in 1753, the naturalist Becker saw tiny unicellular organisms no more than 2 mm in size under a magnifying glass. They responded with light to any irritation.

The phenomenon itself has received the name "bioluminescence", which literally means "weak living glow". Bioluminescence is also called "cold" light, because it does not come from a heated source, but is caused by chemical reactions with oxygen. By the way, there are still glowing bacteria and fungi in nature. Thanks to bacteria, spoiled fish and meat products, as well as festering wounds, glow, to which Paracelsus was already paying attention. Well, at night you can sometimes notice glowing filaments of myceliums, which during the day will seem to you as ordinary rotten ones.

24 july 2018

Much has been written about rest on the Sea of \u200b\u200bAzov, its advantages and disadvantages are described in detail ...

However, there is surprisingly little on the network about this sea of \u200b\u200binformation, except for those addressed to specialists. And this despite the fact that the Sea of \u200b\u200bAzov is in many ways unusual, scientists believe that it was formed as a result of a global natural disaster around 5600 BC. e., that is, already in historical times. In this article, we tried to eliminate some gaps in the knowledge of tourists who are happy to relax in the resorts of the warm and sunny Azov coast, and here we present little-known information about the Sea of \u200b\u200bAzov.

Shallow water and other "records"

The fact that the Azov Sea is the shallowest in the world is known, perhaps, to everyone. The deepest depth is 13.7 meters, which is a trifle by sea standards. But few know about another "world record" belonging to him. The Sea of \u200b\u200bAzov among the inner seas of the planet is the most remote from the World Ocean. Including from the Atlantic Ocean, to the basin of which it belongs. Another "record" is the all-Russian, this is the smallest sea of \u200b\u200ball washing the shores of our country.

Heat and ice

The temperature in the upper layers of the water in the resort areas of the coast sometimes rises to 30 degrees Celsius in summer. In winter, bays and coves in the same zones are often covered with ice. In history, there are cases when the water area of \u200b\u200bthe Azov Sea was covered with ice almost completely.

To whom the crucian carp, to whom the shark ...

Many large and small rivers flow into the Sea of \u200b\u200bAzov, bringing millions of cubic meters of fresh water annually. And the narrow Kerch Strait cannot provide it with real, "sea" salinity, here it is three times lower than the average in the World Ocean. Low salinity leads to natural paradoxes. So, river fish such as pike perch, crucian carp, pike are found in the Sea of \u200b\u200bAzov.

And they are here with stingrays, sharks and even dolphins! True, sharks are small here, quite safe and are extremely rare off the coast.

And the waves are quiet here ...

The Azov Sea can be called the "quietest" in the world. The highest wave ever observed here did not exceed 4 meters. On average, the height of storm waves in the seas and oceans is 7-8 meters, waves (tsunamis) with a height of more than 30 meters are known, but no such cataclysms have been noted in the Sea of \u200b\u200bAzov.

Kerch Strait is expanding

In 1068, Gleb Svyatoslavovich, a Russian prince who ruled at that time Tmutarakan (the most distant Russian principality, at the mouth of the Kuban), measured the distance between the extreme points of the Taman and Kerch peninsulas on ice. This was the first known attempt to measure the width of the Kerch Strait. The measurement showed the result of about 20 kilometers. Today, 950 years later, this distance has increased by three kilometers. Either the prince was mistaken, or the strait has expanded over the years - there is no consensus among scientists.

It also glows!

If you are lucky and you go on vacation to the Sea of \u200b\u200bAzov in August, you can witness an amazing spectacle - the night glow of the sea. The popular belief that algae is glowing is wrong. There is even less reason to speculate about some connection between this glow and the level of radiation. Scientists call this natural phenomenon "bioluminescence", its cause is the accumulation of a large number of living microorganisms at the surface of seawater.

Clean, azure ...

Another misconception about the Sea of \u200b\u200bAzov is based on stories about some unprecedented turbidity of its water. In reality, the Azov water is very clean, the sand covering the seabed and located quite close to the sea surface is an excellent natural filter. Waves and wind can sometimes raise the sand from the bottom, and the water can get a little turbid, but the wind dies down - and the water again becomes transparent, with a beautiful azure tint.

Over the four seas

As mentioned above, the Sea of \u200b\u200bAzov is the most remote from the World Ocean. It is separated from its "native" Atlantic Ocean by as many as four "intermediate" seas - the Black, Marmara, Aegean, and Mediterranean. Therefore, and also because of the narrowness of the Kerch Strait, there is never any ebb or flow.

Deep and dear

At the bottom of the Sea of \u200b\u200bAzov, more precisely, in the bowels of the earth under its water area, and in the coastal regions, there are large oil and gas fields. Fortunately for campers and fishermen, they are not being developed, the mining process is considered too time consuming and expensive.

How to see ...

The Sea of \u200b\u200bAzov, by European standards, is not so small. Two whole European states could freely settle in its water area - the Grand Duchy of Luxembourg and the Kingdom of the Netherlands. And the total length of the sea coastline is 2,688 kilometers.