The importance of mollusks, both in nature and in human life

To overestimate the importance of mollusks in nature is very difficult, because they are an important link in the food chain. First of all, they serve as food for fish, crustaceans, birds and animals. Along with this, mollusks play an important role in biocenotic connections, and their number in the World Ocean reaches 2.2 billion tons.

Bivalve mollusks are natural filters. When water passes through their mantle cavity, it is cleared of microorganisms and organic residues. Numerous experiments show that on average each of them thus cleans up to 30 liters of water per day, while reducing its contamination by about 250 times. Realizing the enormous importance of mollusks, many world states are now taking measures to restore the water biocenoses to ensure environmental protection. This is done by settling mollusks in places where they can become part of biological self-purification.

The great importance of mollusks in human life is associated, first of all, with their use in food. Food can be mussels, oysters, scallops and many others. The fact is that in their meat there are so many elements and vitamins that are easily absorbed by the human body. In some European countries they are even bred specially. It should be noted that for humans, the importance of mollusks is not limited to this. In some varieties, pearls of decent size grow. In order for their development to begin, the mantle must be irritated by some body of foreign origin. A pearl can be called formed only in the event that the layer of mother-of-pearl is finally formed. After that, pearls are used to make various jewelry.

The industrial importance of shellfish should not be underestimated. Pearl shells are made from shells of gastropod varieties, as well as from freshwater pearls. At the same time, an ink bag of squid and cuttlefish is used to produce carcasses and brown sepia of the highest quality.

Despite all this, the value of mollusks is not particularly positive. There are also negative aspects. In particular, some of them cause serious damage to agriculture. For example, naked slugs in search of food destroy crops of cereals and other plants in the garden. A lot of harm is also applied to the grape snail. Some types of pulmonary freshwater mollusks act as intermediate hosts of trematodes. A whole series of them belongs to the stone-carver. They take an active part in the process of destruction of rocks.

In the rivers and reservoirs of the Azovo-Black Sea basin, a variety such as dreisena is very common. This mollusc is considered the only freshwater species that leads an attached lifestyle. As a rule, it settles in pipes and all sorts of biotechnical structures that fail in the course of its intensive reproduction. There are also species that damage structures in the ports and bottoms of ships. In this case we are talking about shipworm.