The long-awaited spring has come, and, as it happens annually, the topic of floods, their prevention and readiness of the relevant structures for the meeting with the elements.
Despite the fact that natural cataclysms associated with an increase in the water level in rivers occur annually, still constantly confusing the wording - they talk about floods, then on floods, then on flood. In this article, we would like to distinguish these concepts and explain that such phenomena cause causes.
First of all, it is necessary to explain the difference between flood and flood. According to modern scientific ideas, the flood is the largest water of the river, regularly repeated in the same seasons. For the period of flooding, as a rule, a significant part of the annual flow of the river is accounted for up to 80%. Antipode of the flood is the integrity - the period of the lowest water level in the river. During the year, the rivers of a certain type of power and water regime in accordance with climatic characteristics are naturally replaced by flood and interlene.
There is a few different order with a phenomenon that happens irregularly. This is by chance of a sharp and short-term rise of water level, an increase in water consumption in the river. Unlike flood, floods can happen at any time of the year. They are not related to the natural processes of the water regime of rivers.
Thus, one thing is the annually repeated flood on the rivers of the Russian plain in the spring period due to the melting of snow (for these rivers it is characterized by snow food), and quite another thing - a sharp rise in water on the same rivers, for example, in summer, after unexpectedly falling abundant Rain, which should be called a flood.
The fact of water lifting itself is a natural, nor random - not called a flood. This is a phenomenon, so to speak, another kind. Flood is flooding water, which can occur as a result of lifting water level in the river, lake or sea.
Flooding can be caused by both flood and flood.
It is important that the flood is already definitely a natural disaster, which is a consequence of the rise of the water level in the river. Actually, settlements, fields, communications suffer from flooding, i.e. Flooding. Causeing its water lift in the river can be classified differently depending on how natural and expected this phenomenon.
From the foregoing it follows that each spring in our latitudes is updated with the problem of combating the effects of floods caused by the spring flood.
Indeed, for the rivers of the moderate climatic belt, it is characteristic of spring flood, but it is explained in different ways.
The rivers flowing through the taiga, mixed and broad-sized forests, forest-steppe and the swollen steppes on the territory of the European part of Russia are characterized by snow. Accordingly, the flood on them falls on the period of the most active melting of the snow (March - April), gradually "moving" from the south to the north.
South south, in dry steppes and semi-deserts, it is already necessary to talk about rain nutrition. However, the peak of precipitation here also occurs on the spring, so the flood comes around at the same time.
East of the Urals, in Siberia, in the areas of continental and sharply continental climate, stretching up to the Gugjur Range on the border with the Far East, the situation is similar. Here the rivers prevailing snow and, therefore, spring flood. The local peculiarity is that the abundant snowing occurs a little later - as a rule, in May.
The specific situation has developed in the Far East. The monsoon climate of a moderate belt is dominated here. It is characteristic of it: arid winter (with winds from sushi at sea) and wet, rainy summer (with winds from the sea on land). In accordance with the peculiarities of the climate for local rivers, the rain-powered rain nutrition is in the summer.
Thus, the spring flood is a specific pattern of natural zones, which include most of our country, and not at all universal rules.
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The flood is the time of the biggest water of the river. In the European part of our country, the flood usually falls for the spring of the snowstation, when the flow of water from all overhangs rushes to the bed of the main river and its tributaries. The amount of water in the river increases very quickly, the river literally "swells", can leave the shores and flood the floodplain areas. The flood regularly repeats every year, but may have a different intensity. [...]
The flood - the phase of the largest water river with a high and long-term rise of water level is usually accompanied by the water outlet from the bed to understand. The flood is caused by the main source of nutrition of the river (on the plain rivers of Russia - the Spring Snowtone) and is repeated in the same season from year to year with a different intensity. [...]
If the flooding becomes rare, and their height decreases greatly, then the first consequence of such a regime is the cessation of floodplain deformations. Education and development of sleeves, characteristic of the process of unfinished meal and for flooding multiplicity, become impossible. Therefore, the regulation of the flow of rivers with these types of the channel leads to a gradual collection of them in one channel, that is, it helps to transform them into freely messenger or in the river with a barbal type of the channel. This transformation occurs, of course, slowly - for its completion, we need many dozens of years. [...]
The volume of the flood is numerically equal to the total amount of water, the river during this period. One of the characteristics of the spring flood is a layer of its flow (see § 134). During the spring flood of the river, the river rushes most of the annual flow - from 50% in the north to 90% and more in the south. [...]
Spring flood on rivers usually begins in the first days of April. During the earlier in the early spring, the beginning of the spring flood can be observed in the middle of the third decade of March, and in protracted cold spring - at the beginning of the second half of April. Spring rise is accompanied by significant intra-day oscillations. The duration of the rise is 3-10 days. The duration of the period from the beginning of the spring flood is observed at the end of August - early September. [...]
The duration of flooding an average of 12-30 days. The beginning of a summer interiance is timed to the last decade of May. The lowest summer level and minimum costs fall on July-August. [...]
On the general background of an increased wave of flooding both on the rise, and separate floods are observed (see Fig. 87). Their appearance is caused by changing weather and changes in the intensity of melting. Sometimes floods are the result of rapid reset of water from glacial lakes or other tanks in the body of a glacier caused by a breakthrough of ice jumpers or mines. Cases of such floods were observed, for example, in 1958 on the Seldar River, arising from the Fedchenko glacier, and its upper influx. M. Tanymass. Sometimes floods reach catastrophic sizes, cause destruction and accompanied by human victims. The breakthroughs of glacial lakes are known in many glacier districts (Alps, Cordillera, Himalayas, Scandinavia, Karakorum, etc.). [...]
The maximum level of spring seals in Astrakhan: the average multi-year level is 322 cm, the maximum observed level is 428 cm. The possible level of repeatability once every 10,000 years per gamma distribution - 566 cm, in a power distribution, this level is achieved once every 730 years. Possible level repeatability once every 10,000 years in power distribution is 664 cm. [...]
Change (%) of mineralization M and concentration of sulfate and chloride ions in the flood of IV integrity for 1950 -1983. [...]
Based on the results presented, it can be concluded that the absence of a flood in 1996 in the spring caused a number of changes that were similar to those observed in the excessive receipt of organic substances - high numbers and biomass of zooplankton, the dominance of proofing and branching crustaceans (Andronikova, 1996; Wings, 1996 b). [...]
In the interests of recreation, it is desirable to fill the reservoirs not in the initial period of flood or flood, accompanied by the greatest turbidity of the flow. It is necessary to ensure sufficient flow of reservoirs. [...]
Water exchange between the river and hydraulically connected with it by aquifer during periods of flood or floods is called coastal regulation of the channel drain. [...]
Lifestyle. Live in reservoirs with transparent water, mainly on rivers. Arrive in the period of flood or later. On nesting habitats are distributed after some decline of water. [...]
Changing the flow regime is associated with different seasons. If the spring and autumn seasons are due to flood and rain floors are characterized by increased flow rates, then in the summer in the middle in many areas the minimum or practically absent. Interlets occasionally disturb the rain floods, for which small watercourses, characterized by weak hydrological inertia, react with sharp, but short-term increase in water level and consumption. [...]
It should be noted that the water regime of Bashkortostan rivers is characterized by a sharply pronounced wave of spring flood and a relatively stable state of expenses and levels (from April to June). For the period of flooding accounts for about 60% of the annual flow, and in the period of the summer and winter interlease - respectively. [...]
The rivers under investigated by us belong to the Upper Volga Hydrological District. The average dates of the beginning of the spring flood occur at the beginning of April. Behind the spring flood should be low summer-autumn interleavers, which is installed at the end of May - mid-June and ends in October - early November. [...]
Thus, for zooplankton, small rivers is characterized by secondary cyclic (seasonal) succias, and an indignant factor - flood - in a geological scale, it uncently supports the river supersystem at the stage of mature youth. [...]
Observations on the mandatory program on watercourses are carried out, as a rule, 7 times a year in the main phases of the water regime: during the flood - on the rise, peak and recession, during the summer interlayer - with the lowest consumption and when the rainy flood passes, in the fall - before Iceproom , as well as during the winter in the winter. [...]
In beaver ponds, as in any other river biotope, the beginning of the seasonal sukzsessia zooplankton is due to the end of the spring flood. The flood is the most powerful, cyclically repeated event. A feature of flooding as an ecological phenomenon is its predictability (Rech et al., 1988). After it, with the beginning of the heating of water and the population of biotopes with pioneer species, there is a pattern of regular, directed development of zooplankton depending on the existing factors. The flood can be viewed as a violation only when the normal seasonal variations of the river level are exceeded (in one direction). In 1996, there was almost a complete absence of a flood. In addition, a feature of the 1996 growing period can be considered another violation of the hydrological regime - heavy rains and floods at the end of July. Samples were taken during periods of hydrological spring, summer and autumn on the beaver ponds of the Chimsor Rivers, Loši and Sparks. [...]
The upper pH range is constantly exceeded, especially in the winter-spring period. This trend has been preserved in subsequent years (Table 4). During the flood and the summer-autumn pass, the pH value in all watercourses stabilized and did not go beyond the scope of the MPC. [...]
In the line "Moisturizing" of the table 3, specify whether the shore is in this place dry (insufficient moisturizing), normal, wet after rain or flood (temporary excessive moisturizing) or swampy (permanent excess moisturizing). [...]
Mineralization of water ranges from 40 mg / l during the period of spring-summer flood to 175 mg / l during the winter period. The ionic composition is characterized by a high content of NSO. The content of organic substances (according to the COP) is slightly (0.6-22.5 mg / l) in the winter integrity, and during the half the water reaches maximum values \u200b\u200band is 29.0-33.0 mg / l. Oxygen regime for a year is satisfactory (at least 67%, with the exception of the period of the decorative, when it is 25%). [...]
Due to the seasonal changes in the river flow, the distribution of portable river water of suspended substances during the year is unevenly. For example, the Volga in Chkalovsk in a spring flood carries 79% of the annual flow of balanced substances; In the summer and autumn, 19.5%, in winter - only 1.5%. [...]
The opening of rivers occurs in the first second decade of April. At the Ufa Plateau, individual areas of rivers are revealed earlier, due to the foci of the criminal unloading of karst waters. Maximum floods on all Rivers Bashkortostan falls for April. The amplitude of the oscillations of the level on the rivers is different (from 170 to 760 cm), but it is characterized by a gradual increase in it from the source to the mouth. The duration of the flood ranges from 22-49 days in low-water years to 62-102 days - into multi-water. The duration of the recession levels on rivers significantly exceeds the duration of the rise. [...]
The simplest is one-time regulation. Under the conditions of snow nutrition, characteristic of the majority of rivers of Russia, one-time regulation comes down to the following. Before the start of the spring flood, the useful capacity of the reservoir is fully released. The beginning of the flood serves as the beginning of the annual water cycle. In the flood, the reservoir is filled. Surplus the flow of water is reset through the dam. Then there comes a long period of work, when the established schedule from the reservoir adds regulated water costs. If the flow is exceeded above the return, which may be, for example, during the autumn rains, the reservoir is partially filled, and then it goes again. If, we, as a result of a high autumn inflow by the end of the cycle, the water reservoir remains in the reservoir, it is reset through the dam, and by the beginning of the next spring flood, the reservoir capacity is empty again. Thus, the stock is redistributed only within this water management year. [...]
Calculation of the passage of a given flood with reservoirs with well-known management rules (task 4) refers to the class of tasks of one-time modeling. It includes the hydraulic calculation of the flood waves in the natural flow of the river and in reservoirs, as well as the detailed calculation of the functioning of hydroells of hydraulic constructions. The task is calibration in relation to modeling the rules of high-waters in the river network with reservoirs, where the hydraulics of the natural channel and reservoirs is considered in a simplified form. [...]
The intra-permanent regime of turbidity and expenditures of suspended nanos depends on the erosion materials entering the river network, the nature of the erosion of the flow and its water regime. On rivers with spring floors, the material washed from the surface of the pool most intensively enters the river network in the first half of this phase of the water regime. In the composition of the nanos during this period, small fractions prevail ([...]
For the forest zone, the most significant differences in the content of organic substances are the most significant. Loaded water (surface-timer and soil-surface origin) enter the channel network during the period of the peak of the spring flood. Water of soil-ground origin is quantitatively dominated in the partial network in the transition period from flooding to the summer interlease, i.e. During the downturn of the flood. During periods of severely pronounced summer and winter interoperability in the river network there are water of ground-based origin. The ratio of waters of various genesis in total drain for the bezles of mixed forests The following is: slope water - 50%, soil-loaded - 27%, soil - 23% (Zaslavskaya, 1998). Surface-slope water predominate in the forest zone. They are characterized by small mineralization (5-100 mg / l) and bicarbonate-no-calcium composition (Zaslavskaya, 1998). [...]
The opinion of the famous domestic hydrologist D.Ya is deserved. Ratkovichi, expressed by him on the "New Gazeta" pages: "Tsimlyan reservoir - a huge utility capacity of 1.5 billion m3. Any rainy flood it will intercept. But the high snow fodder will stop not anyone. It so happened that since 1952, when It was put into operation to zieml, there were no such beds yet. However, this does not mean that it will not be. What happens - the water will have to dump. But all the waters of Don over the past 50 years are built up with pioneerlands, sanatoriums, boarding houses. All this water element is mocking. And with huge human victims "[Ratko HIV, 2002]. [...]
The main purpose of the antisombosor line is to prevent the excessively fast filling of the reservoir, which can cause single water discharges. It consists of a filling branch that prevents excessively fast filling of the reservoir in the period of flooding the requirement of timely transition to increased recovery [...]
Mineralization of water in R. Volga in the Volgograd area varies from 200 to 300 mg / l; With intermane expenditure of 5100 m3 / s in the Volgo-Akhtuba region, 260 mg / l; In the waters of R. Akhtube, Buzan and Berechet at expenses, respectively, in 1040, 700 and 1025 m3 / s. It is about 280-290 mg / l. In the sublimity, mineralization increases to 360-390 mg / l at the expenses of R. Volga in 10300 m3 / s, R. Aahtuba, Buzan and Bereke - within 500-6300 m3 / s. Due to the surface flush, the sulfate-ion content in R. Volga at the Volgograd level - 36-74 mg / l. [...]
The objectives of the creation of reservoirs may be different: satisfaction of industrial, utility and agricultural water supply, irrigation, hydro and thermal power engineering, shipping, forestry, fisheries, recreation, sections of the peaks of salons and floods, etc. All this is definitely gives a large national economic effect. At the same time, it is impossible not to note possible negative consequences. [...]
Protection of horse marshes. High swamps play a major role in maintaining environmental equilibrium of the environment, established natural complexes. They serve as a source of nutrition of many rivers, regulate the spring stock, making less turf and devastating flood; Spring and rainwater accumulated in them support groundwater levels that eat the surrounding fields and meadows. In addition, the swamps are the habitat of fishing birds, animals and give rich yields of berries. In the harvest years, the swamps collect up to 3 t / ha cranberries, 2 t / hectares lingers and blueberries, a lot of blueberries and other berries. In monetary terms, this gives income several times greater than the poached area of \u200b\u200bthe same area. For these reasons, the swamps should be approached extremely carefully, carefully weighing the possible consequences. [...]
Environmental tension, for example, caused by the unfavorable manifestation of the natural hydrological mode of rivers - a seasonal drying or freezing of small rivers, as well as changes in the hydrological regime under the influence of the creation of reservoirs (cutting of the field of flood and the formation of wormwood in the lower beaches of the hydraulic circulation), industrial, utilities and agricultural water intake in large sizes, appreciated in table. 7.1.1. It should be noted that the anthropogenic factor itself in these cases reflects the needs of people in the use of water resources due to the need to generate electricity, water supply, etc. However, the changes in the hydrological regime occurring are influenced not only to the entire river ecosystem, but also on the living conditions and activities of people associated with rivers (feedback). [...]
Rain floods are called relatively short-term and fast levels of levels and an increase in water expenditures under the influence of rains falling in the river basin and such a quick decline. The relative short-term passage of floods, small flow volumes compared with the flood and different times of passing them during the year on the same river and constitute the difference in floods from the salons. [...]
In seasonal fluctuations in the transparency of water, the lakes are scheduled for winter and autumn maxima and spring and summer minima. Sometimes the summer minimum shifts on the autumn months. In some lakes, the smallest transparency is due to a large number of applications delivered by tributaries during the period of flood and rain floods, in the other - the massive development of the zoo and phytoplankton ("blooming of water), in the third - accumulation of organic substances. [...]
Returning phenomena are distributed over long distances in the depository river basins and constitute on Ob (up from the mouth of Irtysh) 350 km (14% of the river length), northern sucking -248 km (33%), Lyamin - 137 km (49%). The consequence of the subpoits is a long flooding of river floods. Subjects and long-term floods contribute to the transformation of rivers in these periods from the drainage factor in the factor of replenishment by the waters of interracial spaces (Malik, 1977). [...]
In the territory Russian Federation Every year there is a significant number of natural catasta ROF, as a result of which the national economy is not only applied, but people are dying. The greatest danger of the earthquakes, tornadoes, hurricanes, as well as floods caused by spring floods and strong rains. [...]
Meanwhile, the entire concept of strategic flood protection is based on the adoption of a more careful decision. Consider this moment several more. For most of the first and second order rivers, there are more or less representatives of the observations of the drain, including in the period of the female and floods. Meanwhile, observations of the maximum runoff almost nowhere can be recognized as satisfactory in terms of estimating the likelihood of its exceeding, since the error of such an assessment is higher than the one itself the probability itself. [...]
Maximum costs and levels are kept on some rivers for long (1-2 days), on other standing high levels is delayed (River of the West Siberian Plain). Sometimes there are several maxima, which is a consequence or return of cold weather, alternating with new warming, or the development of flood development on the main river and its tributaries. [...]
Melting of snow and thawing soil in the forest is slower than on open spaces. S.N.Golubchikov leads the following series, characterizing the average miniature intensity of the snowmall: Out\u003e Field\u003e Berezovo-Osin Forest\u003e Conifer-albertic\u003e Elannik. Thus, due to the presence of the forest, the duration of the flood is stretched and its levels are reduced. The smoother force of the flood contributes to the fact that the speed of intravenous runoff in the forest is usually less than on arable land. [...]
The hydrographic network of this area, located on a latitudinal waterproof site, is poorly developed, closed and does not have a constant drain. The steep east of the boards of the Gorbina are drained significantly Sylf - they are dismembered through Ka Ladier 8-12 km, 10-30 km, the Says of rek, also have a latitudinal direction. In the upper reaches and at a hike in Lonbi, they are a hammer of embedded beds with a chain of the Ples. Pre-site. [...]
The inconsistency of water consumption and drainage between participants (components) of the IHC leads to contradictions. Thus, water transport is interested in maintaining shipping depths in the lower bes of the hydropower plant in the navigation period, and hydropower - on the contrary, in the accumulation of water into the reservoir for more intensive use of it in the autumn-winter boot peak. During the same flood, hydropower is interested in accumulating water in the reservoir, and the fisheries requires significant freights from the reservoir in order to maintain the optimal depths of spawn and shallow, in which the fish lives. The resolution of such contradictions occurs in the process of formation of the IKK, and their elimination is one of the most important conditions for its optimal functioning. [...]
One of the most important directions for the development of methods for calculating and forecasting the flow (new generation methods) is the development of physico-mathematical models and their implementation on the basis of knowledge of the geographically common patterns of the formation of spring flow, taking into account the landscape structure of the regions. As indicated Yu.B. Vinogradov, arsenal of mathematical models of flow formation, and in particular fellows and rain floods, quite large, and in general, mathematical modeling in hydrology finds development paths. At the same time, when creating most complex models, natural requirements imposed on the fact of their inclusion in the system of the settlement methods of engineering hydrology into the system. In particular, it concerns the volume and availability of the source information. [...]
Let's try to understand this phenomenon, which, apparently, has a global character in geophysics, on some examples. Let's start with the Nile floors. [...]
Thus, the maximum of radioactive contamination, the source of which is the "lighthouse", was formed in the lowerhouse floodplain of the leaks about 15 years later the main discharges of the nuclear enterprise, that is, around 1965. Concentrations 239.240RI and 137SS found in these soil layers were the largest. The established fact can be explained by secondary movement of contaminated soils. The source of radionuclides could be floodplain soils, from where, during a flood, polluted particles come to the river. [...]
The reserved stock should be set differentiated depending on the hydro-ecological classification of water sources, which covers four groups of rivers. 'And group 1. Rivers with developed floodplains (with the development factor / GR 5 and the average duration of flooding floods in the spring-summer period over 20 days). For these rivers, the allowable water supply and water intakes are allowed to maintain at least 20 days during a period of flooding with a middle layer of water on nonma at least 0.5 m with repeatability close to natural. With such a drain, by the time of infusion, the floodplain is provided by the necessary conditions for the spawning of fish. [...]
Water consumption is called the amount (pronounced in cubic meters) water flowing through the closing target of the river per second. Changing water consumption is the root cause of water levels in the river. Measuring the flow of water is expensive, therefore, it is often a graphic dependence between the amount of consumption and water levels (consumption curve) is often on the basis of a series of measurements on this target of the river. The graph of the flow of water flow in time is called a flow hydrograph. The flood volume (flood, flood) is measured in millions of cubic meters and is determined by multiplying the sum of the average daily costs for the flood at 0.0864 (the number of millions of seconds in the days). To determine the damage from flooding, it is necessary to determine the maximum level and the maximum water flow rate during the flood time. The maximum water level serves as a criterion of spontaneous hydrological phenomena (floods, congestion, wind harnesses), leading to flooding of settlements, crops, communications. The same flood parameter allows you to determine the area, layer and the duration of the flooding of this area. It is also important to know the rate of water lift. When designing hydrotechnical structures, not only the parameters mentioned above are taken into account, but also their repeatability. [...]
Especially increased anthropogenic loads on the main river artery of the European part of Russia, which turned into a system of low-descent reservoirs. More than 2,600 rivers fall into it, which annually bring about 23 billion m3 of untreated drain (petroleum products, pesticides, heavy metals, etc.), about 300 million tons of solid particles; Only the rice fields of the Astrakhan region are merged by about 600 tons of pesticides (bees, 1994). A significant amount of harmful substances comes from the Astrakhan gas chemical complex (up to 1-2 million tons of sulfur gas annually). Before the construction of the dams of Volzhskaya water from Rybinsk to Volgograd reached 50 days (in a flood - for 30), and at present - for 450-500 days. All this led to the fact that the self-cleaning of the Volga decreased in tens of times. After the accident in 1986, the Dnieper, Dniester, Danube and Volga basins were polluted with radionuclides. The result of the unreasonable economic activity of man has become a sharp deterioration in the reproduction of valuable species of fish, a decrease in their reserves and volumes of catch. If in 1956, the total catch of fish in the Volga-Caspian pool was 280 thousand tons, in 1988 - only 76.5 thousand tons of bream for three decades decreased by 4.5 times, Vobl - 8 times , Herring - 16 times, periccation 2.5 times. Similar situations are noted in the Don and Moscow river basins, the water of which are contaminated with petroleum products, phenols, heavy metals, pesticides and other toxicants; The eutrophic process is particularly intensively in the r. Moscow, where the amount of cyanobacteria has increased dramatically, the water quality has deteriorated, and it has become a similar to the "blooming water." [...]
Consider briefly the most common methods for the regional assessment of natural resources of groundwater. Its essence consists in accounting for specific hydrogeological conditions of river basins and the patterns of underground flow into the river from all aquifers of the drainage zone. The mode and dynamics of the underground flow into the river from individual aquifers drained by the river network are determined by the conditions for the occurrence and nutrition of soil and artesian waters in this river basin or its parts and the position of the unloading places relative to the river-cut. In cases where drained aquifer horizons have a hydraulic bond with the river and during the spring flood, the groundwater support occurs, which is typical for most plain rivers, the dismemberment of the river flow hydrograph to the surface and underground components is made taking into account the processes of coastal regulation of the underground flow (Kuden, 1960).
When a significant part of the annual flow is passed (up to 80%), floodplain flooded, and sometimes low terraces.
The flood is caused by a reinforced proliferation of water, which can be due to: Spring melting of snow on the plains; Summer melting of snow and glaciers in the mountains; abundant rains (for example, summer monscons).
The flood caused by the Spring Snowtone is characteristic of many plain rivers, which are divided into 2 groups: rivers with a predominance of spring flow (for example, Volga, Urals); Rivers with a predominance of summer runoff (for example, Anadyr).
The flood due to the summer melting of mountain snow and glaciers is characteristic of the rivers of Central Asia, the Caucasus, the Alps, and the summer monsoon rains caused by the South East Asian Rivers (Yangtze, Mekong).
Floods - a sharp and short-term rise of the water level in the river, an increase in water consumption resulting from heavy rains, intense melting of snow, glaciers, volley discharges of water from reservoirs. The duration of the flood from several pieces of an hour to several days. Unlike the flood, it happens at any time of the year and is not repeated periodically. The following floods can form floods. A significant flood may cause a flood - intensive flooding of a large area with water above annual levels, one of the natural disasters. The most often floods occur as a result of river spills with abundant precipitation and intense snow melting.
The flooding of settlements, structures, communications, agricultural land, natural complexes as a result of the effects of water and the rapid flow has significant negative consequences for these objects, farms and the population.
Intensive river spills lead to the death of people, agricultural and wild animals; destruction or damage to buildings, structures, communications; loss of material values; crop death; Wheel of fertile soils and change of landscape. The secondary consequences of flooding is the loss of the strength of various structures as a result of the erosion and torture, transferring water from damaged harmful substances and pollution of vast territories, complication of the sanitary and epidimic situation, the inching of the terrain, as well as landslides, collaps, accidents and industrial facilities.
Depending on the material damage inflicted and flooding area, the floods are low, high, outstanding, catastrophic.
Low (small) floods are characteristic of plain rivers. Their frequency is once every 10-15 years. At the same time, no more than 10% of lands located in low places are poured with water. As a rule, low floods are not related to significant material losses and human victims.
High (large) floods lead to flooding of large areas in river valleys, which is associated with the need for partial evacuation of the population and material values. High floods occur once every 20 - 25 years and cause significant material and moral damage, overpaying about 15% of agricultural land.
Outstanding floods are characterized by the coverage of whole river basins, applying large material and moral damage, violation of economic activities in cities and rural areas, the need to conduct massive evacuation measures from the flooding zone, the protection of important national economic objects. Outstanding floods are repeated once every 50 - 100 years and overtake up to 70% of farming.
Catastrophic floods are characterized by flooding of extensive areas within one or more river systems, a temporary cessation of production and economic activities, a change in the lifeflow of the population, huge material losses and human victims. Catastrophic floods are repeated once every 100 - 200 years and over 70% of agricultural, cities, settlements, industrial enterprises, roads, communications are flooded.
The prerequisite for the organization of protection against affecting factors and the consequences of floods is their forecasting. For forecasting, a hydrological forecast is used - a scientifically based prediction of the development, nature and waters. The forecast indicates approximately the time of the occurrence of any element of the expected mode, for example, the opening or freezing of the river, the expected half of the flood, the possible duration of the standing of high water levels, the probability of ice plug and other. Forecasts are divided into short-term - up to 10-12 days and long-term - up to 2-3 months or more. They can be local (for individual sections of rivers and water bodies) or territorial, containing information that are summarized in significant territory on the expected sizes and periods of the phenomenon.
In accordance with forecasts, warning protective measures are carried out from flooding. By the nature of the impact on the element, they are intense and extensive.
A complex of intensive measures, the basis of which make up engineering activities, includes:
- regulation of the flow of rivers (redistribution of the maximum flow between reservoirs, the transfer of flow between the pools and inside the river basin);
- the fencing of the territories of the dams (interpretation systems);
- an increase in the bandwidth of the river bed (clearing, deepening, expansion, rigging;);
- increasing the marks of the protected area (a device of bulk territories, pile grounds, a swing on the floodplain lands in the expansion and development of new urban territories).
Extensive measures include:
- change in the nature of economic activity in the heated territories, control over the economic use of hazardous zones;
- removal of objects with sleek territories;
- carrying out protective work during the flood period;
- evacuation of the population and material values \u200b\u200bfrom zones of flooding;
- elimination of flood consequences.
Material prepared on the basis of open sources information
And evaporation. In areas with a cold and temperate climate, the role of air temperature is also very significant.
Water regime phases
The following water regime phases are distinguished: flood, flood, interleum, ice-bearing, ice drift.
- Flood - annually repeated in the same season with a relatively long increase in the water content of the river, causing its rise to its level; It is usually accompanied by the yield of water from the cross-channel and flooding the floodplain.
- Flood - A relatively short-term and non-periodic raising of the water level resulting from the rapid melting of snow during thaws, glaciers, heavy rains. The following floods can form floods. Significant floods can cause flood.
- Intera - annually repeated seasonal standing of low (inter-market) water levels in rivers. Usually, the interactions include low-water periods lasting at least 10 days caused by dry or frosty weather when the water water is maintained mainly in soil power with a strong decrease or termination of the surface drain. In moderate and high latitudes distinguish summer (or summer-autumn) I. winter Mezhny.
- Ice station - The period when there is a fixed ice cover on watercourse or reservoir. The duration of the ice station depends on the duration and temperature mode of the winter, the nature of the reservoir, the thickness of the snow.
- Icewater - Move of ice floes and ice fields on rivers.
Uneven during the year, the supply regimen of rivers is associated with the unevenness of the loss of atmospheric precipitation, the melting of snow and ice and the receipts of their waters in the river.
Water level fluctuations are caused mainly by a change in water consumption, as well as wind action, ice formations, human economic activity.
Types of water regimes
Typical water modes of rivers differ in climatic zones:
- Equatorial belt - Multi-fashion rivers throughout the year, the stock increases in the fall; Surface stock of exceptionally rain origin
- Tropical savanna - water content is proportional to the duration of the wet and dry periods; The predominance of raindrops, while in a wet savannah, the flood continues 6-9 months, and in dry - three; Pretty substantial summer stock
- Mediterranean type subtropics - Middle and low water, prevailing winter stock
- Propean subtropics (Florida, Lowholder Yangtze) and the adjacent areas of Southeast Asia - the regime is determined by monscons, the greatest water water and the smallest - winter
- Moderate northern hemisphere belt - Increased water water (in the south mainly at the expense of rain food; in the middle lane and in the north - flood of snow origin at a more or less stable summer and winter interopera)
- Moderate belt in a sharp continental climate (Northern Caspian and Plain Kazakhstan) - short-term spring flood when driving rivers for most of the year
- Far East - The mode is determined by monscons, summer flood of rain origin.
- Districts of many years of Merzlota - drying rivers in winter. On some rivers of Eastern Siberia and the Urals during the ice stations are formed to be apparent. In the subarctic, the melting of snow cover is late, so the spring flood goes to the summer. On the polar coating glaciers of Antarctica and Greenland, the processes of ablation occur on peripheral non-pending bands, within which peculiar rivers are formed in ice rods. They feed exclusively by glacial waters during short-term summer.
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Watch what is "spring flood" in other dictionaries:
spring flood - High and long-lasting water lifting on flat rivers caused by the spring melting of snow. SYN.: Snow Film ... Dictionary on geography
- ... Wikipedia
The phase of the water regime of the river, characterized by the largest water, high and long-term rise in the level of water, usually accompanied by the water outlet from the bed to flood. Unlike floods, it is regular, repeated annually, in ... ... Geographic Encyclopedia
The phase of the water regime of the river, annually repeated in these climatic conditions in the same season, characterized by the greatest water, high and long-term rise in water level and the snow caused by snowdrop or a joint melting of snow and ... ... Dictionary rapid situations
flood - phase of the water regime of the river, annually repeated in these climatic conditions in the same season, characterized by the greatest water, high and long-term rise in water level, and caused by snowdown or sharing snow and ... ... Technical translator directory
I; cf. Rolling the river, coming at a certain time due to melting of ice, snow, seasonal rains; A period of such a spill. Spring n. Village cut off floors. Stuck on the road in p. / About abundance, large quantities of P. electric ... ... encyclopedic Dictionary
Flood - phase of the water regime of the river, annually repeated in these climatic conditions in the same season, characterized by the greatest water, high and long-term rise in water level, and the snow caused by snowdown or joint melting and ... Civil protection. Conceptual terminological dictionary
flood - I; cf. a) spill rivers, coming at a certain time due to melting of ice, snow, seasonal rains; A period of such a spill. Spring sex / Die. The village is cut off flooding. Stuck on the road to sex / Die. b) rashes About the abundance, large quantities ... ... Dictionary of many expressions
Flood - annually repeated usually in the same season of the year the increase in water in rivers, Max. Water consumption when on p. It takes up to 80% of the annual flow, floodplains and low terraces flood. Spring P. is caused by melting snow on the plains, summer P. ... ... Russian Humanitarian Encyclopedic Dictionary
Here and the ice on the river cracked,
River Zasheel
And with yourself winters of the shackles
Resets boldly;
Coast steep moat,
Spilled wide ...
Splash and noise of water raw
Heard from afar.
OF. Surikov
Rarely, which of us did not observe the ice drift during the spring flood, when the rivers go out of the banks and spread widely by floodplain. It is both terrible, and very beautiful sight. The solid mass of large and small ice floes is moving rapidly. It is dangerous to be on one of them. At steep turns and in narrowes of the bed, Ice closely becomes closely: the bluish-green ice floes are crawled on top of each other, unfold, climb on the edge, drown and again pop up. It seems there is no such force that could curb the smalldly element. Nature during the ice plant can be unpredictable and joking it undesirable.
Opening rivers precede warm days . After the average daily air temperature is set above zero, the compressive rhesis of the ice shakes are broken, off the coast of the free of ice of the water "Color". These are the first signs of starting the river opening. A few days after the appearance of the "Zakrain" there is a platoon of ice: high ice fields are slowly round into long-range - move at a certain distance and again frozen on the spot. With each hour, the melting water of snow arrive, they will crush the ice fields on separate floors, and after several raboys begin the spring ice-frequency. At the beginning of the flood, the water level rises slowly, and then, especially on large rivers, the rate of level lifting increases to 0.3-0.5 m per day.
The height of water lifting depends on many factors: from weather conditions, the calendar time of freezing or opening the river, hydraulic characteristics of the water flow and the structure of the river bed, from the square of river basins, from the amount of snow that dropped over the winter and intensity of its melting. With a non-deplete spring with frequent cold returns, the snow comes out gradually, why levels and expenses of spring waters are low, and the flood is strongly delayed and vice versa, steady warming with rains leads to intense snow melting and sharp rise water levels on rivers. The calculation of the height of the maximum water levels during the spring flood requires extensive and detailed information about the factors that determine them. At Vologda, the most interest is the forecast of the spring flood on the Sukhona River in Great Ustyug.
On the territory of the Vologda region spring flood
It does not begin at the same time, and this is not surprising - because due to the difference in the climatic conditions of different areas of our region, the front of the opening of the rivers moves from the south-west to the northeast. Especially rapidly spring flood passes on the Sukhona River. The opening of the river begins in the upper reaches and gradually moves downstream. The wave of a flood overtakes the front of the Snowtone and meets on its way the areas of the river, still covered with thick and durable ice. Floating ice, meeting a strong ice cover, accumulates in large quantities, forming temporary congestion. Due to the accumulation of ice floes in the narrowings of the river bed, or at the opposites of the bridges can also occur in places. Water is looking for exit, raging, raging, with a crackling and crashing, breaking the obstacles on the path. Day, two, or even three, sometimes the icy dam of the jam, while the rustling of spring water is above the dam will not break the obstacle. During congestion, the water level on the Sukhona River in the Great Ustyug area rose to 926 cm (in 1929), to 969 cm (in 1953), to 963 cm. (1998). Also in 1957, in the area of \u200b\u200bthe village of Koching, the maximum level was 928 cm, and in the breaths in 1917 - 1063 cm.
Head of OGMO Popova L.V.
To prepare the article used materials: Seasons N. Danilova and A. Kommerich; http://www.restterra.ru/causes-flood/natural-cases/floods-and-flash-floods.html;tTPS: //www.gorodtotma.ru/721-suxona.html
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