1. Using maps of the atlas, give a comparative physico-geographical description of the Black and Azov Seas.
In the atlas for the 9th grade there are physical maps, they show the relief of the bottom, depicted with the help of isobaths – lines of equal depth. These maps show that the Black Sea is located to the south and is much deeper and larger. Pay attention to the map of the ecological state of the seas, the scheme of the structure of the waters of the Black Sea.
Additional information is contained in the text of the textbook paragraph and table 6 of the appendix. The Sea of Azov freezes. Black is not. The salinity of these two seas is different. The Azov Sea is more fresh, the salinity of the Black Sea is two times lower because of the flowing powerful rivers, than in the World Ocean. In the Black Sea, the species composition of fish caught is much broader.
2. With which countries of near and far abroad can our country carry out communications through the Azov-Black Sea basin, the Caspian Sea?
The Azov-Black Sea basin connects Russia with European countries and Turkey; The Caspian Sea – with the countries of Asia. In addition, from the Black Sea through the Bosporus and the Dardanelles, as well as the Marmara Sea, ships enter the Mediterranean Sea and can enter the ports of Southern Europe, North Africa, and the Near East.
3. What kinds of economic activities are affected by the emerging environmental problems of the seas of the south of Russia?
Most of all, the ecological problems of the southern seas in reducing the catch of fish. Further pollution of the water areas can lead to a decrease in recreational potential – few will want to rest on the beach, covered with a film of petroleum products and household garbage.
4. Do you think it is possible to restore the biological productivity of the Azov Sea? What are the possible ways of recovery?
In the text of the paragraph the main reasons for the decline in the productivity of the sea are named. This increase in salinity due to a reduction in the flow of the Don and the Kuban and the influx of Black Sea waters; due to the construction of dams, the passage of fish to spawning grounds, as well as general pollution.
All these factors can be eliminated, and then the productivity of the Azov Sea will be restored, only this will require considerable resources and is unlikely to be realized in the coming years.
are the changes in the level of the Caspian Sea that affect the nature and economy of the land adjacent to the sea?
The atlas shows the graphs of the level of the Caspian Sea in historical times and for the last 160 years. They show that these changes are changeable: the periods of recovery are replaced by a fall in the level, etc. At the same time, the coastline recedes or approaches.
Primorye settlements, fishing or port facilities are usually built directly by the sea. When the level is raised, they are flooded, and when they are lowered, they leave the sea. If we recall that the contact of land and sea has a continental shelf, the depths change gradually, we can imagine how a small decrease in the level will lead to a significant removal of the shoreline. In this case, lifeless saline spaces with decomposing algae appear on the surface.
When the level is raised and the estuaries of the flat rivers or coastal depressions of the land are flooded by the sea, elongated shallow bays with winding, low banks are formed. They are called limans. The waters of the estuaries are characterized by a considerable content of salts and are used for medical purposes.