Angara River

The 1,779 km long Angara River is a river in southeast central Russia that serves as an outlet for Lake Baikal. The Angara also acts as a major tributary of the Yenisei River, which itself ultimately drains into the Arctic Ocean. Arising from Lake Baikal, the river flows across the southern parts of the Central Siberian Plateau until it joins the Yenisei at Yeniseysk, draining an area of around 1,040,000 square kilometers in the process. Irkut, Oka, Taseyeva, and Iya are some of the important tributaries of the Angara River, while Irkutsk and Bratsk are two of the largest major cities located along the river basin.

History

Prior to the arrival of the Neo-Siberians, the Angara River Basin was inhabited by hunter gatherers like the Buryats and Khori-Tumed peoples, evidence of whose presence has been detected as early as the 13th Century. The arrival of the Neo-Siberians led to the establishment of a fur trade route along the rivers, and mining activities also developed at a fast pace in the area. Gradually, settlements like Irtusk and Bratsk developed along the Angara River in the 17th Century, when Europeans arrived in the area to collect fur taxes from the indigenous Buryats. The river now served as a major source of transport for these new settlements. The development of commercial fisheries along the river has also long supported the local people's livelihoods.

Modern Significance Of The River

Currently, the huge hydro-electric power generating potential of the Angara River is being tapped by large hydroelectric power stations based along the river, the most notable ones being those located at four of its largest dams with hydroelectric capabilities. Namely, these are the Irkutsk Dam, Bratsk Dam, Ust-llimsk Dam and the Boguchany Dam, producing an average of 4.1 billion Kilowatt-Hours (kWh), 22.7 billion kWh, 21.7 billion kWh, and 17.6 billion kWh of electricity, respectively, on an annual basis. Though the Angara River does not provide a continuous waterway due to the presence of such artificial dams and natural rapids along the course of the river, short stretches of the river are still navigable by modern watercraft, and some amount of commercial fishing is also carried out in the Angara River.

The River Ecosystem

The climate around the Yenisey-Angara River Basin is a continental type, characterized by hot summers and bitterly cold winters. Annual precipitation ranges between 400 and 600 millimeters in the western part of the basin, and then gradually decreases towards the east. The Eastern Siberian taiga is the predominant existing ecosystem of this region. The vegetation of the Angara River basin is characterized by pine and pine-larch forests, grasses, and dwarf shrubs. Mammals like Siberian musk deer, moose, roe deer, and red deer, and birds like the Siberian blue robin, Pallas's rose-finch, Pacific swifts, and oriental turtle doves, are found in these eastern Siberian taiga forests. A large number of fish species, such as roach fishes, perches, sturgeons, and tenches, are found in the waters of the Angara River themselves.

Threats 

The large-scale construction of dams and reservoirs, though highly beneficial to the local economies of the region, have degraded the natural ecosystems of the river basin to a large extent, as well as displaced large sections of the local rural populations. The constructions of impediments to the natural river flow has affected the migration and spawning habits of fish species along the river's watercourse as well, leading to a massive decline in native fish populations. Also, global warming is though to be leading to losses of water from the Lake Baikal, and has also lowered the water levels of the Angara River in recent years. This water loss is adversely affecting the human communities depending on the river for their livelihoods, as well as the native flora and fauna.