Coral reefs are a valuable ocean resource due to the beauty, variety of forms and indispensability in their ecosystem. The tropical forests of the sea, as coral reefs are also called , are perhaps the most widespread and vivid expression of life in the aquatic environment.
They provide shelter for many marine life, serve as a food source for myriad organisms, form the topography of the seabed, and form patches of island land. For humans, coral reefs are important not only as beautiful objects of nature, which are worth admiring during the holidays, they also protect the coastline from large ocean waves, important building materials - sand and limestone - are formed from their skeletons.
Coral ecosystems are called the pharmacy of the 21st century. Based on the beneficial compounds that were found in this biocenosis, many medications have been created or are under development: antibacterial, general strengthening, improving digestion, cardiac, cosmetic, as well as medicines for treating viral infections, asthma, skin cancer, arthritis.
The class of coral polyps includes more than 6 thousand main species. These marine invertebrates can be solitary or colonize. They also differ in size, in the presence or absence of a skeleton, its forms and composition (calcareous or proteinaceous). Reef structures, however, are capable of forming coral polyps of the madreporic order.
“Stone gardens” are formed not only by these miniature animal organisms. Most coral polyps have a mutually beneficial relationship with unicellular algae, zooxanthellae, which live inside invertebrate cells. It is believed that these autotrophic protozoa are also involved in the construction of the coral skeleton. Other algae — calcareous — play a large role in reef formation; they perform several functions: they create a reef framework, cement various damages, and supply loose material. Some other animal organisms, namely representatives of individual families of mollusks, polychaetes and sponges, are also important for rifting.
The mechanism of nutrition of polyps is interesting. About 90% of the organic matter that forms the microscopic algae of the zooxanthellae during photosynthesis is transferred to the host tissue. The second type of food is external. Coral polyps can capture and absorb prey stunned by stinging cells prey - microscopic zooplankton and small fish.
Reproduction of coral polyps are able to carry out in two ways: sexual and asexual. The selection of male and female gametes also occurs in two ways. In the first, which is called “spawning on the air,” sperm and eggs in large numbers are simultaneously thrown into the water column. A protein “cloud” forms above the coral reef, which attracts many predators that feed on plankton. Gradually, the larvae of polyps, planula, are carried by ocean currents. In the second method of sexual reproduction, only male reproductive cells that freely float until they meet the female coral enter the water.
The asexual reproduction of these creatures is multifaceted: they can be budged in several ways, cross-section, and distributed by broken fragments.
Coral reefs are a unique natural phenomenon, beautiful and inimitable, but, unfortunately, very fragile. Stone Gardens are extremely sensitive to changes in lighting, temperature, salinity and water pollution.
Human activity is one of the most serious threats to the existence of coral colonies, which in recent years have become discolored and die at an accelerated pace. Only joint actions of many countries of the world can stop or at least slow down this process. Recently, marine protected areas have been created in which, with the interaction of authorities and scientists, fishing is reduced and special measures are taken to conserve reefs. There are also world organizations that are making efforts to resolve this issue; they are developing ways to artificially form reefs and accelerate the growth of coral polyps.