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The problem of biological resources

In a broad sense, they cover all the variety of plants and animals living in the oceans, including, of course, algae and plankton. Quite often in the literature suggests that the biological resources of the ocean is enough to feed at least 10 billion people. In this optimistic digital display is significant, though: not all biological resources economically, technically and environmentally feasible and justified to engage in farming. It is difficult finding ways to optimize the exploitation of biological resources of the oceans and is the essence of the problem.
Today, a large proportion (over 85%) for human use of marine biomass belongs to the fish. The rest is accounted for cephalopods and bivalves (mainly squid, mussels and oysters), crustaceans (crabs, lobsters, crayfish, shrimp, krill), echinoderms and some marine mammals. And it is very tiny fraction of the total biomass are until brown, red and green algae, as well as the higher flowering plants.
Experts estimate that the maximum fishing should not exceed 120-150 million tons per year. The current extent of the catch until they reach this critical level (40), but it's still not saying much. Even today, many fish species are on the verge of extinction. Rarely began to fall in fishing nets Norwegian and Icelandic herring, sea bass, flounder, cod, whereas 80% of the total fish catch falls by only 8 species. According to calculations of the FAO, world fish catch with no apparent environmental damage if it can be increased by several tens of millions of tons, it is only through careful compliance catch some "deficient" species and expansion of new types of fishing ocean fish.
Almost all of the world catch (over 95%), as before, is removed from the shelf zone - the continental shelf with an average depth of about 130 m. Such shallow parts of the ocean are quite extensive and sometimes extend over many thousands of kilometers from the coast, but account for only 7-8% of the world's water area . The reasons for such a high concentration of industrial fishing offshore dictated, of course, not only and not so much by considerations of navigation order. A crucial role is played here by the fact that within the very nature of shallow water ideal conditions for nekton, vol. E. Actively moving organisms in the marine environment (as opposed to plankton, passively drifting in the water). There are a lot of sunlight and organic matter, and the latter are rich and the bottom layers, populated by benthos. It is here that the main focus centers of organic life in the oceans, or, according to Vernadsky, "condensation of life." Such thickening, scientists believe, take place there, where the approximated two films - photic layer of the water mass of the Ocean (where sunlight penetrates), especially rich in plankton and benthic rich benthos.
Sometimes expresses the view that the deep areas of the oceans are poor biological resources, is not entirely accurate. "Barely 2% of the total weight of the ocean condensations busy life. The rest of its mass has dissipated life "- which is said Vernadsky. So in this case we are talking only about the main places clusters of biomass actively flowing through the process of photosynthesis and plentiful food for nekton.
Such thickening life sometimes there are within the deep ocean, which is associated with the phenomena of the so-called upwelling, ie. E. Vertical uplift of deep ocean water masses, generously saturated with biogenic particles. One such upwelling is located within the deep-water areas adjacent to the coast of Peru. No coincidence that here formed one of the most productive fishing areas.
By tradition, occupies a leading position fishery in northern latitudes (30 ° s. Lat.), Which gives a little more than half of the world's catch. The contribution of the oceans in the person supplied the seafood is very unequally. In this regard, the Pacific and Atlantic Oceans markedly superior Indian.
Factors affecting the geography of sea fishing, a lot: the natural, socioeconomic, legal. But chief among them is still related to spatial differences in the biological productivity of the ocean. Like the land, where there are vysokoplodorodnye and marginal land, in the ocean clearly distinguish highly productive continental shelf areas of the periphery of the oceans and partially open waters and waters with limited biological resources.
The organization of fishing in very remote areas of the oceans, primarily in the south polar region of the Earth, vol. E. Antarctic moderating influence socioeconomic and technical factors. Meanwhile, the proportion of Antarctic fisheries in the world production of marine products is growing rapidly. Especially great economic importance acquired krill - a representative of the Antarctic plankton, small crustacean to 60 mm in length and a weight of 1-2 g, called chernoglazkoy. At a time when the number of herds kitovpolosatikov for which krill is the staple food, has declined sharply, the accumulation of small shrimp in Antarctic waters, on the contrary, increased. Krill becomes very valuable raw material for the production of fish meal, the value of which, according to experts, higher flour derived from fish.
In the south polar region of human resources involve fish (especially Shad), as well as diatoms, most of the nutritional value of which is proved. For the development of the latter in the Antarctic waters formed the most favorable conditions.
Finally, one can not ignore the cultural breeding of some species of organisms on artificial marine plantations and farms. The fishery called akvakulturoy, was known in ancient times (for example, the cultivation of carp in ponds practiced four thousand years ago, also bred marine fish and oysters). Perhaps aquaculture - one of the general trends in the development of modern marine economy. The argument here is the fact that marine fish farms in a position to give a year from 1 ha to 6 tons of food, which is many times greater than the amount of fish taken from the same area at the moment. However, the organization of aquaculture is possible only in a well-cultivated person areas of the oceans.