One of the most difficult and pressing problems of the modern world is the problem of providing a growing world population with food. At the same time it is closely intertwined with the problem of environmental protection (Grigoriev, Sedova, 2008). Despite a General tendency to the reduction of fish stocks in the seas and oceans are of particular importance in aquaculture, i.e. fish farming, food invertebrates and algae in a controlled environment. Artificial reproduction of fish stocks in natural waters is a complex of measures aimed at the preservation, increase quality and increase fish stocks. These activities include fish farming, fisheries management melioratio, acclimatization of fishes and food organisms, as well as clear regulation of the fisheries.
Sterlet (lat. Acipenser ruthenus ) — fish of the family Acipenseridae. Body length up to 125 cm and weigh up to 16 kg (usually less). Among other sturgeon species is distinguished by the early onset of sexual maturity: males first spawn at the age of 4-5 years, females — 7-8 years. Fertility 4–TIC eggs. Working fecundity of 33 thousand eggs. Spawn in may, usually in beds of the upper reaches of the rivers. Caviar adhesive, is deposited on the stony-pebble ground. It develops about 4-5 days. Adults usually reach a length of 40-60 cm and mass 0.5–2 kg, sometimes there are specimens weighing 6-7 kg and even up to 16 kg. Feeds mainly on benthic invertebrates, willingly eats caviar of fishes. In the fall, in September, is going on deep sections of rivers (ditches), where it spends the winter in an inactive state, not feeding. The regulation of rivers usually improves the conditions of feeding sterlet, but also worsens the conditions of its reproduction. The age limit of sturgeon for 30 years. A valuable commercial fish. Continue reading
For anybody not a secret that summer vacation brings a lot of various positive emotions that may be encountered by everyone who comes to the beach. However, despite the fact that relaxing on the beach is an opportunity to polarinstitutt in the warm waves and bask under the solar rays, there are many other points that can in addition to various amenities and to bring a number of significant troubles.
Therefore, even during rest, should pay attention to the potential dangers and learn about how to cope with them in critical situations, including when trouble brought various sea inhabitants.
The first thing to do before the trip along with the usual charges, to prepare a first aid kit, which will have all the necessary medications in order to cope with various alterations that await us on the rest. This applies to various means to improve digestion, and antiseptics and other medicines, the receipt of which cannot be stopped or required to receive in case of serious health problems. In addition, you should look for information about what animals are a threat in the region, where You go on vacation, and in accordance with data found to acquire the necessary means.
As for the provision of first paasikiventie on vacation after contact with someone from inhabitants of the coastal zone, it all depends on who has had to face. However, as practice shows, most often along the coastline, you’ll encounter sea urchins, jellyfish and stingrays. Despite the fact that the sight of those representatives of the animal world do not pose a serious risk, but the consequences after meeting with the individual instances can be extremely serious. Continue reading