Lena is the largest river in Siberia.She rather big by world standards.In the list of the longest rivers of the world, it ranks tenth.Lena length of four thousand four hundred kilometers.Catchment area is located on an area of almost two and a half thousand square kilometers.Proceeds majestic river on the territory of the Irkutsk region and Yakutia.
Geographical location
Upper River, as well as large areas of swimming pools within its right tributaries are located in mountainous areas of Trans-Baikal region and in the Aldan Plateau.In the area of the Central Siberian Plateau is a large part of its left bank of the pool.The lowest portion passes through the Central Yakut plain.
division
In line with the Lena River are three main sections.The first of them - the top.It goes from the source to where it flows into the river Vitim.The middle section ends where it meets the River Lena.Aldan.In the third, the lower section of the river carries its waters to the mouth.
In the upper reaches of the Lena mode rapid and fast.This area has all the features characteristic of the mountain streams.The flow of water swift and sinuous track.Many places have thresholds.This rocky coast and high.In the upper reaches of the water flow foams and rages, rapidly moving to the north.
mode wayward and the mighty river on the way to changing Kirensk.Here Lena takes its tributary waters.Kirenga and calms down a little bit.Its bed becomes wider and deeper (in some places, the value is ten meters).Rocky shores are retreating.Stones replace the mighty cedars and tall pines, spruce and fir.It grows here and larch.
river becomes even greater power after it falls Olekma - its right tributary.Next to Aldan Lena flows through Prilenskoye plateau.Here, its banks are unique and extremely steep slopes.
Ends average over after Lena meets with his right tributary - Aldan.At this point, the great river of Siberia forms numerous channels with small islands.
in the lower reaches of Lena spreads in all its vastness.In these places, it shows all the power and greatness of the Siberian rivers, which can not but cause admiration and delight.
Power
Fifty percent of its annual flow of the river gets melting snow and precipitation in the form of rain.Additional food sources of the Lena River - groundwater.From them, she gets one or two percent of its flow.Thus, the type of food the Lena River - mixed.But not only these sources increase the flow of Siberian majestic beauty.
Power Lena River - is also all its tributaries.This list includes Aldan and Tea, Vitin and Olekma, Kuta Viluy, Kirenga and young, Sensing and Tuolba, Buotama and Blue.Inflows are of different sizes.The largest of them - rivers Vitim, and the Aldan.
Power inflows is mainly composed of water resulting from melting snow and rainfall.Some flow runoff occurs from groundwater reservoirs.However, its scope is very small, as in the territory of the river flow is permafrost.The only exceptions are those areas where the geothermal sources.
Thus, the type of food the Lena River and its tributaries is the same.He refers to a form of mixed.
Power mode and the Lena River are closely interrelated.At the same time, they are dependent on the total precipitation.For the mouth of the Lena River characterized by extensive spring floods.Poured the river and in the summer.At this time there several times there are high floods.But autumn and winter low water at the mouth of the low.
Power mode and the Lena River is changing dramatically in the spring.During this period, there is a powerful ice and snow cover is melting.During the flood water flow in the area of the mouth may be above the level of 250 000 cubic meters per second.
aquifer
Water regime Lena River characterized by a high tide.In the spring, change the watermark takes an average of ten to fifteen meters.The lower this value reaches eighteen meters.Mode of the Lena River in the summer depending on rainfall.At the same time there are several rain floods.A small drain is typical for winter.
In terms of water content among Russian river Lena is in second place.In terms of its flow, it is second only to the Yenisei.
mode Lena River is characterized by an average annual flow at the mouth, equal to seventeen thousand cubic meters per second.The maximum number is 200 000, and the minimum - 366.
type of water regime of the river Lena saved over its entire length.However, despite this, to various portions of water flow parameters have their values.So, above the mouth of the river Kirenga average annual water consumption is at around 480 cubic meters per second.At the confluence of the Lena River.Vitim this value is 1700. At the mouths Olekma, Aldan and Viluy, respectively, 4500, 6800 and 12 100 cubic meters per second.But in the Laptev Sea, where Lena carries its waters, the annual runoff is about forty-five hundred cubic kilometers.
Suspensions
Together with the waters of the Lena River to the Laptev Sea annually gets forty-one million tons of various solutes.Takeaway also suspended sediments.Their during the year falls into the sea about twelve million tons.Turbidity of water is in the range of 50-60 grams per cubic meter.But the rate of mineralization of 80-100 milligrams per liter.
Freeze
In the cold periods of the year in terms of the water level there is a decline, and the regime of the Lena River in this radically changed.During this period, the surface is constrained by ice.Free River carries its waters five to six months during the year in the south and four or five months in the north.The tributaries of the Lena freezing set a little earlier.The river itself holds down the cold for ten days later.
Freeze is installed in the upper reaches of the end of October.In the bottom - a month earlier.Opening of the ice may be delayed in the upper reaches to the middle of May, and at the bottom - until the beginning of June.
mode Lena River radically changed during spring break.During this period, the formation of the congestion that significantly raise the water level.
thermal regime
water temperature indicators throughout the length of the Lena River have significant differences.Average performance in the areas of the upper and middle reaches are at around plus nineteen.But in cold periods (November through April), the average temperature of the water is zero.
As for the lower reaches of the river, there is a monthly average values are somewhat lower.In the warmer months, they do not exceed seventeen degrees.Significantly longer the period with the zero mark.It begins in October and ends in May.
temperature regime in the upper Lena River delta area it has minimal value.In this connection, in this area there is the longest period of the water ice coating.
spring flood on the river Lena lasts an average of thirty-five days.Moreover, in the upper reaches of this period the least extended.It is twenty-seven days.In the lower reaches of the river spring floods may take up to forty-four days.
Environmental problems
Global warming, which in recent years on the planet, has a negative impact on the river.On the territory where it takes place, in the last forty years have seen the rise of the annual temperature four degrees.In this connection, the spring floods are much more powerful.This destroys the river bank.In addition, there is a movement of islands along the river.Already in 2009, it recorded the speed of their descent, who was twenty-seven meters per year.
Commercial use
Lena is one of the cleanest rivers on the planet.In addition, its channel is not changed man.At Lena is currently not built any dams, hydroelectric power stations and other water facilities.In places located far from populated areas, the water is so pure that you can drink directly from the river.
As you can see, the unique nature of these places virtually saved.This is due to the fact that the economic use of the Lena River are not conducted very intensively.In the absence of this factor influences a large number of settlements, and various hydraulic structures.Despite this, Lena is the main transport artery, located on the territory of Yakutia.It is navigable from the influx Kachug to his mouth.Riverbed to Ust-Kut may take place only vessels have shallow draft.Navigation period lasts in the upper reaches of the order of one hundred and sixty days, and in its lower reaches - one hundred and twenty.Yakutsk is the main pier and Zhigansk, Vitim and Lenek, Budun and Kirensk, Kachug and Zhigalovo Olekminsk Sturgeon.Navigable and some tributaries of the Lena.Among them Vitim and Olekma, Kirenga and Viluy and Aldan.
in the Lena River basin produced mining.Found in this area gold-bearing areas and diamond deposits.Rich in Pool Lena rock salt and iron ore, mica and natural gas.In the lower reaches of the local fisheries.It is home to the burbot and cisco, whitefish and whitefish Siberian.
