Among the natural resources of the planet, water sources occupy not the last place. Oceans and seas, rivers and lakes, groundwater and glaciers - they all play a role in the ecological system of the region, many are used in various fields of industry or agriculture. In this material we will try to understand what the minimum, maximum and average water levels in rivers are, what is the reason for the fluctuations and whether there is a threat to human life.
Water wealth of the planet
The definition of "water wealth" is not scientific, scientists in the field of natural sciences, theorists and practitioners use another term - "hydrosphere". But, in fact, this is the same thing - all the waters existing on the planet, water sources that are on the surface of the earth and underground.
Of the greatest importance for human life is fresh water, therefore, it is not the seas and oceans that people give primary attention to, but to smaller sources. Environmentalists monitor the purity of water and the water basin, keep records and control of various natural processes. Raising the water level in the river, recession, causes and consequences are among the priorities.
Scientific Definition
At present, rivers make up only 0.0001% of the total hydrosphere of the planet. But the onset of the world's oceans on land, which has been observed over the past decades, is not as catastrophic as the annual sharp drop or rise in the water level in rivers in different parts of the world.
Level is the height of the surface, which is measured relative to a certain constant plane. For comparison, by default for such a constant plane take an ordinary. The word has Latin roots, it means “norm”, “normal, proper condition”, “compliance with accepted and existing rules”.
Everything is okay
The average water level in rivers is an ordinary thing; for its calculation, observations and calculations have been carried out for many years. At water gauging posts you can see a footstock - this is the German word, equal to the Russian "level gauge".
It looks like a bar or lath, divisions are plotted on the front surface, the main purpose of the geodetic adaptation is to help scientists conduct research, fix the exact level at a given, specific moment in time.
Zero footstock - is considered the norm for a particular reservoir, the fluctuation of water in one direction or another - an occasion for professionals and ordinary residents to think. It is important to know why this is happening, the process of raising and lowering is caused by natural causes or is the result of a person’s life, leads to normalization of the environmental situation in the region or to disaster.
Caution: Level Up
During the calendar year, all terrestrial water sources of the planet undergo periodic fluctuations in levels. According to the hydrological regime in force in each region for a certain period of time, the indicator can reach minimum or, conversely, maximum heights.
Europe is characterized by a decrease in summer, and the highest water level in a river or other body of water is observed in the spring, during floods. The main reason for this phenomenon is an increase in ambient temperature, and, accordingly, melting of snow. The second period of rise can be observed in the autumn period, when the rainy season begins on the European part of the continent.
A sharp rise - the reasons are known
The regime of precipitation and changes in climatic conditions are two main reasons that affect the level of water sources, regardless of the nature zone in which they are located. A short-term rise in the river's water level in springtime can be caused by the rapid melting of snow with a sharp increase in temperature. The amount of winter precipitation can also contribute to the increase in water volumes.
In summer, there is another reason for the short-term increase in water level - a large amount of rainfall that falls over a relatively short period. The minimization of the consequences is facilitated by the study of weather forecasts and the peculiar preparation for rains and showers, verification of the effectiveness of the locks, the strengthening of coasts, and the evacuation of residents from the coastal zone.
Decrease - be in trouble!
Earlier in Russia, the word “low-water” was used to define the concept of “low water level in a river”. It comes from the word “boundary” - boundary, extreme line, today, even in scientific use, the term “low water” is used.
On Russian rivers, a decrease in the level can be observed twice a year - in the summer and winter. The reasons are a decrease in precipitation, a decrease in the volume of water coming from underground sources. The natural decline, which, according to scientists, is within the normal range for a river, does not pose a threat to the inhabitants of the region, since it is temporary. The return to normal occurs naturally, after precipitation or artificial, with the existence of a system of locks.
Water - at a minimum
What threatens the minimum water level in the river to people and the ecosystem of the region, what measures should be taken to prevent this? Low water is a record low, and it can be a messenger of an approaching environmental disaster in a particular region.
Elevated water sources located in the temperate zone survive a decline in the level twice a year. This is due to a skew caused by a change in the nutrition balance - due to a decrease or absence of precipitation over a long period of time, the surface runoff also decreases. At the same time, groundwater supply cannot maintain an average level. If the low-water period lasts from 10 to 30 days, it is considered short, more than 30 days - long.
Who suffers more - nature or people?
The critically low water level in a river or lake is the cause of many ecosystem and human troubles. Among the negative consequences are the deterioration of the environmental situation in the region, the occurrence of interruptions in drinking water, a decrease in the volume of transportation of goods and passengers by river transport, and the suspension of shipping.
A decrease in water reserves negatively affects the state of flora in the region; the balance of plants changes in favor of more hardy, adapted to the conditions of an arid climate. The number of fauna representatives is decreasing, some of them are dying, others are leaving the coastal areas in search of new water sources.
In many regions, rivers are a source of drinking water; a low level affects consumption and a decrease in water quality. The transport system of the region suffers if it is “tied” to the use of water transport.
The average water level in the rivers ensures that the agricultural industry will function as usual, all the necessary indicators will be respected. Plants will receive sufficient volumes of water and produce the expected yield.
Hydrological posts are always on guard
The result of many years of observations by scientists - the average water level in rivers - is fixed in documents that establish standards in a particular state. In the USSR, a standard was developed regarding the determination of the level and discharge of surface water; the same standards are currently in force in Russia and in other countries of the world.
According to this normative act, it is envisaged to place hydrological posts, to install water gauge rails in those places where it is possible to ensure their normal functioning and operation.
What are the graphics for?
To determine the water level, ordinals are used with a scale, the unit of measurement of which is 1 centimeter. Previously, the indicator was determined only visually, today in many places the fixation is carried out automatically using recorders.
To analyze the state of a water source, water level graphs in rivers are used. Recording is carried out regularly, at certain intervals, but at least once a day. Specialists (or devices) record the time (hour, minute), day, month, year and level indicator.
The graphs show how the water level changes during the day, month, year, analysis of this information allows scientists to make more or less accurate forecasts for the future. In turn, this helps to prevent a catastrophe, minimize negative consequences, and preserve the ecological situation in the region, the health and lives of people.