Saimaa
The Saimaa [ sɑi̯mɑ ː ] ( Suur- Saimaa also Finnish for " Big Saimaa ", Swedish Saimen ) located in the southeast of Finland and is the largest lake in the country. It is about 4,370 square kilometers and drains to the east across the river Vuoksi (Swedish and Russian Vuoksen Vuoksa ) in Lake Ladoga in Russia.
Geography
The Saimaa is a system of many together verbunder lakes ( lakes or part ), covering about 4,370 square kilometers. The largest of these lakes are part: Saimaa 1377.03 km ², Pihlajavesi 712.59 km ² 416.35 km ² Puruvesi, Haukivesi 560.43 km ² 601.30 km ² Orivesi, Pyhäselkä 361.10 km ² 196.68 km ² Enonvesi, Pyyvesi 29 75 km ² 24.23 km ² and Ukonvesi. When considered as a whole, the Saimaa lake system is the fourth largest lake in Europe. Its coastline measures 14,850 km. In Saimaa there are a total of 13,710 islands with a total area of 1850 km ². At its deepest point the Saimaa reaches a depth of 85 meters, but on average it is only seven meters deep and therefore holds a total of less water than the smaller area Päijänne.
The Saimaa emerged as the other lakes in the Finnish Lake District when the melting of the glaciers of the Vistula ice age. In the south prevented the Salpausselkä terminal moraine, the postglacial land uplift, so that it is accumulated in the north a drainage of melt and rain water until about 5,000 years Saimaabecken and a more than 400 km long lake from today Iisalmi in the north to Salpausselkä formed. Only after the breakthrough of Vuoksi at the point of Imatrafalls around 5,000 years ago, he found a natural drainage, so that lowered the water level and the present-day topography began to emerge.
The Saimaa Canal Opened in 1850, the length is 42.9 km (of which 19.6 km on the Russian side ) connects the Saimaa with the Gulf of Finland. The difference in height is 76 m and is achieved with eight locks. Since 1991, he is free to boaters use. About other channels, such as the Taipalekanal at Varkaus and Konnuskanal at Leppävirta, the Saimaa was connected with the other large lakes in the Finnish Lake District, so it mainly for rafting, today for industrial as for the tourist IWT has a significant importance in the past.
Cartography
The opening of the Saimaakanals brought a detailed survey of the waterways of the lake. An initial depth map, Karta öfver Saimens watt system, was made in 1859 and only recorded details of the main waterways from Lappeenranta to Mikkeli, Savonlinna, Iisalmi and Joensuu. From 1857 then the former naval officer Johan Bartram prepared on behalf of the Finnish Senate a detailed depth map of the entire lake system. This work was continued in 1940 working for depth map of Lake Saimaa with Aaro Hellaakoskis.
Ecology
In Saimaa survived the Saimaa ringed seal ( Pusa hispida saimensis ), a subspecies of the ringed seal (Phoca hispida ). She is one of two subspecies of the ringed seal, which live in fresh water. There is now some 260 of these animals. The Saimaa is further distinguished by its abundance of fish. This is primarily the salmon mentioned.