Drought is not a mysterious phenomenon, but ways to combat it are still not known to man. Is drought a consequence of climate change? Description of drought

Stable weather, lack of rain, high air temperatures with extremely low humidity levels - all these factors lead to drought.


This period can last from a couple of weeks to two or three months in different areas.

Why does drought occur?

Drought is associated with a climatic phenomenon such as a high anticyclone. At its core, this is the formation of an area of ​​increased atmospheric pressure. A high anticyclone is warm, characterized by clear weather, lack of precipitation and wind, and low mobility of air masses.

In temperate latitudes, droughts, as a rule, occur in steppes, less often in forest-steppes. According to scientists, drought occurs once every two or three hundred years even in forested areas. In the subtropics and subequatorial zone, droughts occur regularly, since precipitation in such regions occurs only during the rainy season.

Types of drought

Depending on where there is an acute lack of moisture, a distinction is made between atmospheric and soil drought. Atmospheric conditions create increased moisture evaporation due to the abundance of sun and reduced air humidity. During soil drought we're talking about about the depletion of the soil due to the lack of rain, due to which the supply could be replenished groundwater.


If this period lasts for a long time, then lakes, ponds, and small rivers begin to dry up, and then we can already talk about hydrological drought. Depending on the season, drought can be spring, summer, or autumn.

How dangerous is drought?

During a period of drought, the flow of water to the root system of plants stops, the moisture consumption exceeds its influx, the water saturation of plant tissues critically decreases, and the normal conditions of its growth are disrupted. Spring drought can destroy early grain crops, summer drought harms fruit plants, early and late grains; autumn drought destroys winter crops.

Drought can lead to ignitions and long-lasting fires in steppes or forests, as well as to peat fires, which entail extremely dangerous smoke for the body.


Drought is detrimental to people. According to statistics, more than a million people have died from droughts in Africa over forty years. The UN even established World Drought Day – it is celebrated on June 17th.

How to deal with drought?

Measurements of moisture reserves in the soil and accurate calculations of the volume of snow cover help predict the likelihood of drought. For example, if the moisture reserve in a meter layer of soil in the fall does not exceed 50% of the average annual level, or the thickness of the snow does not reach half the average for many years summer period measurements, then the risk of drought is very high. And this means that you should take protective measures.

To prevent drought, a number of actions are taken to retain moisture in the soil and retain snow on the fields. The land is plowed deeply, transverse plowing is carried out on the slopes, and the microrelief of the surface of the arable land is changed. It is especially important to do this on high-density soils.

With the help of ploughing, harrowing, and cultivation, they try to maintain the soil in a loose state. Timely feeding of fertilizers, regulation of snow melting processes, and accelerated pre-sowing soil preparation help maintain the viability of plants.


Effective method– combination of crops different types crops that require different amounts of rainfall at certain times of the year. For example, winter crops are resistant to summer droughts, but need moisture in the fall; early spring crops, on the contrary, require special moisture in the first half of summer. Agronomists also grow special drought-resistant varieties of various crops.

Introduction

1. Formation of droughts

2. Types of drought

3. Known droughts

4. Fighting drought

5. Deserts

Literature

Introduction

Drought – a significant lack of precipitation compared to the norm for a long time in spring and summer, at elevated air temperatures, as a result of which moisture reserves in the soil dry up (through evaporation and transpiration) and unfavorable conditions are created for the normal development of plants, and the yield of field crops is reduced or is dying.

1. Formation of droughts

Droughts are usually accompanied by hot weather, extremely dry air, and sometimes strong, burning winds, which creates all the conditions favorable to increased evaporation of soil moisture. The soil dries out first from the surface, then, thanks to cracks that appear, deeper and deeper, and the plants growing on it, unable to get the water they need, die. But it happens that even with enough rain, plants suffer from lack of water. Yes, in the steppes southern Russia, where in summer precipitation falls mainly in the form of showers, extremely abundant in the amount of water they bring, but short-term and rare, drought is a common phenomenon.

The dried out earth does not have time to absorb even a tenth of the fallen water, as the rest of its mass quickly falls into ravines and gullies. But even that portion of the moisture that manages to be absorbed into the ground does not benefit the plants, since, thanks to the onset of hot weather again, it evaporates very quickly. The onset of drought in many cases depends on a number of other reasons, among which, undoubtedly, is the destruction of forests on a huge scale.

It is precisely where the presence of forests is most important “as regulators of the life of rivers and springs”, in the upper reaches of rivers and along their slopes, that they turn out to be almost completely eliminated (for example, at the upper reaches of the Volga, Don, Dnieper, etc.). As a result of such predatory destruction of forests, there are strong floods in the spring. The rivers turn as if into drainpipes, through which a huge mass of water, instead of being distributed over several weeks, rushes through in 3-4 days.

At the same time, up to 60% of it is lost, compared to what was previously retained by forests and fed rivers and springs in summer time. The shallowing of many, previously large, water rivers (Bityug, Vorskla) and a general decrease in the water surface and, associated with it, air humidity depend on such a rapid passage of spring waters. Thus, the destruction of forests causes undoubted harm, especially to agriculture, both because through this the regulators of weather elements (humidity, wind, temperature) are destroyed, and because, following deforestation and drought on the slopes, the mass of inconvenient land increases.

The strength and impetuousness of the dry wind is so great that it demolishes crops, blows away the surface layer of soil and covers fertile fields with sand. Its activity does not stop in winter, but at this time of year it acts in conjunction with the northeast winds. Terrible snowstorms, sometimes lasting a whole week, are not uncommon in southern Russia. From the high steppe, snow is carried by these winds into ravines and ravines, leaving the fields bare and depriving them of spring moisture. Thus, the onset of drought depends not only on the meteorological conditions of a given year, but is also prepared by the owners themselves through the destruction of forests and plowing up steep slopes. The essence of drought is the lack of moisture in the soil during the period of plant growth, which always has a detrimental effect on their development and often happens the main reason shortage, and sometimes complete failure of the harvest of grain and herbs.

Droughts with adverse consequences for crops are observed especially in the steppe zone, less often in the forest-steppe and in the south of the forest zone. On ETC for 65 years 3. damaged crops in the lower Volga region 21 times, in the east of Ukraine and in the Central Chernozem regions 15–20 times, in the west of Ukraine 10–15 times, in the Kuban 5 times, in the Moscow and Ivanovo regions 1–2 times . During the dry years (1924 and 1946), the number of consecutive days without rain in a large area was 60–70.

There are atmospheric droughts, i.e. a state of the atmosphere characterized by insufficient precipitation, high temperature and low humidity, and, as a consequence, soil drought, i.e. drying out of the soil, resulting in insufficient supply of water to plants.

The atmospheric regime during drought is determined by the predominance of stable anticyclones, in which the air in clear weather warms up greatly and moves away from the saturation state.

The onset of drought is usually associated with the establishment of an anticyclone. The abundance of solar heat and dry air create increased evaporation (atmospheric drought), and soil moisture reserves are depleted without replenishment by rain (soil drought).

During drought, water enters plants through root systems becomes more difficult, the consumption of moisture for transpiration begins to exceed its influx from the soil, the water saturation of tissues decreases, and the normal conditions of photosynthesis and carbon nutrition are disrupted.

2. Types of drought

Soil drought– soil drying associated with atmospheric drought, i.e., with certain weather conditions during the growing season, and leading to insufficient provision of vegetation, especially agricultural crops, with water, to its suppression and reduction or loss of yield.

Physiological drought- a phenomenon when, at high daytime temperatures in spring, transpiration of tree species increases, and water supply by the roots is not provided due to low soil temperatures. The plant begins to starve, despite the presence of a sufficient amount of water and mineral compounds in the soil.

Droughts in Russia according to the seasons of the year can be spring, summer and autumn. In the driest years, droughts span two or even three seasons, that is, a spring drought turns into a summer drought, or a summer drought turns into an autumn one, or a drought that began in the spring continues until late autumn.

Spring drought has the most harmful effect on the first period of growth of spring crops. This drought is characterized by low relative humidity, but low temperatures and cold, dry winds. Often, prolonged winds cause dust storms, aggravating harmful effect spring droughts.

Summer cause severe damage to both early and late grain crops and other annual crops, as well as fruit plants;

Autumn dangerous for winter crop seedlings.

Particularly harmful is the prolonged spring drought that developed against the background insufficient hydration soils by precipitation in the autumn-winter period with small reserves of soil moisture. In such conditions, plants develop very poorly, and even the onset of rainy weather will not be able to completely eliminate the consequences of drought: the yield will be reduced.

For example, in 2002–2003, summer in the Republic of Adygea began at a time close to usual (May 1–2). Summer was characterized by hot, dry weather at the beginning of the period and moderately warm, rainy weather at the end.

Of the 15 summer decades, 7 decades had positive deviations of air temperature by 1–5° and 7 by 1–2° below the long-term average. One decade was within normal limits. The highest temperatures (35–37°) were observed in the first ten days of July, the third of August and the first of September. The number of days with a maximum air temperature of 30° was 29–47 days.

The sum of effective temperatures above 10° for the summer period was 1565–1820, which is 60–180° higher than the long-term average value.

3. Known droughts

In Russia, its southern and southeastern outskirts, drought is a common phenomenon, recurring at more or less long intervals. The history of our fatherland has preserved many memories of the years in which the population suffered not only from hunger, but even from pestilence. Probable cause Such disasters were drought (“hunger from crop failure, crop failure from bucketloads”), although exact information about the reasons that gave rise to such crop failures and their size has not been preserved. Only about 1833 and 1840. It is known that the shortage of crops in these years depended mainly on drought. In terms of the size of the area affected by crop failure, the greatest crop failure was in 1891, when 21 provinces suffered from drought, and the shortage of grain was determined, in comparison with the normal average crop failure, at 80 million quarters.

A severe drought has continued in Cyprus for several months. Temperatures in the winter months exceeded +30°C, and local reservoirs were almost empty. Since the beginning of the year, the water supply deficit on the island has amounted to more than 17 million cubic meters of water. Last week, severe water supply cuts began across the country.

The drought that plagued the United States Southern Europe and Southwest Asia in 1998–2002, was associated with water temperatures in the tropical Pacific and Indian Oceans. For four years now, some areas in the northern hemisphere have received less than half their annual rainfall. This dries up farms, depletes water bodies, and lowers groundwater levels. And it is still unclear when this drought will end.

4. Fighting drought

Fundamental measures to counteract drought should consist of increasing running water in a given area, increasing groundwater and preserving moisture reserves. This can be achieved mainly through continuous afforestation, especially in the upper reaches of rivers and along their slopes, and by planting forest edges and hedges along the passes. Only under such conditions is it possible to properly distribute the snow cover, which would provide moisture to the soil. Both the government (since 1813) and private individuals have been working in this direction, mainly in the steppe zone. Another means of combating drought is artificial irrigation of fields and meadows. It was borrowed from mountainous areas where high-water rivers flow, which, moreover, have a large fall. Water from such rivers is diverted through canals to the fields and distributed over their surface using furrows, or directly floods them completely. In areas that are flat and shallow, such as our steppes, for example, they take advantage of winter moisture reserves. Melt water is collected by drainage canals into ponds, usually located in the upper reaches of ravines, and the valley and slopes of a given gully or ravine are irrigated with water from such reservoirs. Another method is also possible, called watering. Several rows of dams or rollers are built along the slope, parallel to its ridge. spring water, held by them, as the upper areas are moistened, it descends lower and lower. In the Semirechensk region, they make huge glaciers out of snow on the passes, cover them with earth or straw to protect them from rapid melting, and gradually use this supply of water, conducting it in small ditches to the fields. In addition to these measures, the farmer still has many means at his disposal to prevent drought.

This year, a number of regions of the Volga region were affected by drought, Southern Urals, and since July 31, due to drought, a state of emergency has been declared in a number of areas in the south of the Kirov region.

As modern scientists note, drought refers to an extreme interaction between man and nature. In conditions of insufficient precipitation, plants die, which inevitably leads to depletion of food resources. People begin to experience not only thirst, but also hunger. Droughts are especially common on the African continent. Thus, according to statistical data, only in Kenya were registered in 1836, 1850, 1861, 1880, 1899 - 1901, 1913 - 1918, 1925, 1936, 1954, 1961, 1970 - 1971. In the late 1960s and early 1970s alone, drought in the Sahel on the southern edge of the Sahara Desert led to the death of 100,000 people.

Another continent that is constantly experiencing drought is Australia. Here, severe droughts were recorded in 1864 - 1866, 1911 - 1916, 1963 - 1968, 1972 - 1973 and 1991 - 1995. The central (interior) regions of the country are suffering the most from drought in Australia.

There are three types of droughts: meteorological, hydrological and agricultural. Meteorological drought occurs when precipitation is delayed for a long time, resulting in moisture deficiency. Hydrological drought occurs due to a shortage of water supplies in surface layers soil and a decrease in groundwater levels, as well as water levels in rivers, lakes and other bodies of water. Agricultural drought occurs when soil moisture is reduced and plant growth is limited.

As practice shows, periods of drought are closely intertwined with forest and peat fires. In recent decades, these two natural phenomena have occurred with increasing frequency in different regions the globe, including those that are not considered arid climate zones.

In the context of global changes in the Earth's climate great importance It also has accurate weather forecasts. IN in this case The method of the famous Soviet astronomer and meteorologist A.V. Dyakov, which he developed on the basis of the theories of K. Flammarion and A. Chizhevsky, and outlined in his work “Foresight of nature for long periods on an energy-climatic basis,” most fully justified itself.

Practice has shown that the accuracy of predictions of this method, based on sunspot cycles, for example, for the region Western Siberia(for which the scientist made forecasts) was 90 - 95% for ten-day predictions and 80 - 85% for menstruation. And this despite the fact that the traditional method of weather forecasts gives only about 60% of matches. It was these scientists who, back in February 1972, predicted a dry and fire-hazardous summer, which was marked by numerous forest-peat fires and required the coordinated efforts of the army, police, fire and forestry services, as well as groups of volunteers from the population, to tame the fiery element.

Using this forecast, towards revelry natural disaster it would be possible to prepare in advance. Unfortunately, Soviet Marxist-Leninist science was suspicious of the work of A. Chizhevsky, and A. Dyakov’s methodology was recognized only at the end of 1972. Its timely use would have avoided numerous casualties and major material damage. Especially when you consider that back in the late 50s and early 60s, these scientists predicted five severe droughts. The scientist’s forecasts were carefully studied in France, Japan, Cuba, and countries Latin America, where they were taken very seriously, given that they always came true.

Along with droughts, accompanying forest and forest-peat fires cause many problems for humanity. The causes of such fires can be either anthropogenic (unextinguished fires, cigarettes, deliberate arson) or natural (lightning discharges during hot and dry spring-summer weather). According to expert estimates, from lightning strikes to globe More than 20 thousand forest fires occur. Their geography is determined by climate, and their distribution and scale are determined by numerous factors environment(soil moisture, air temperature, density and type of trees, relief, etc.).

Evidence from ancient chronicles states that outbreaks of forest fire intensity in the distant past always occurred during periods of drought. However, forest fire statistics became regular only in the 20th century. On the territory of Russia, large fires were recorded in 1915, 1972, 1984, 2002, 2010.

Severe forest fires are observed in last years and in many other countries. Thus, they were noted in the summer of 1997 in Jordan and Indonesia; in the summer of 2001 - in the USA and Australia; in April 2000 - in South Korea, in July 2000 - in Bulgaria, Turkey, Greece, Albania, Yugoslavia; in the summer of 2002 - in the central regions of Russia and in the Canadian province of Quebec, in August 2005 - in Portugal, in July-August 2007 - in Bulgaria, Greece, Serbia, Montenegro, Hungary; in April 2008 - in Chelyabinsk region, Khabarovsk Territory and Amur region Russia. The American states of California and Australia suffer from forest fires almost every year.

When forecasting fires resulting from natural disasters, weather forecasts directly related to the elements of air, fire and water should be taken into account. So, it’s no secret that in dry years, especially when strong wind the likelihood of fires increases significantly. “Dry” thunderstorms are fraught with a similar disaster. In this case, wind speed is directly related to the speed of fire spread. An early forecast in this area will make it possible to reduce the negative impact of these factors by creating additional water reserves for fire extinguishing purposes, creating forest protection clearings, plowing fields, roads, economic facilities, timely mowing of dry grass, and other activities.

The difficulty of making forecasts using traditional methods currently lies in the increasing disruption of natural balance. Which leads to an increasingly uneven distribution of moisture and heat in different regions. Thus, scientists note that in 2002, drought affected many African countries, while floods occurred in the east of this continent. In August of the same year, there was a severe drought in western India, and floods occurred in the east of the country. We can observe similar processes in recent years in various regions of the planet.

For thousands of years, our planet, civilizations, and humanity have been faced with phenomena that contribute to both their formation and development and destruction. Echoes of cataclysms and natural disasters reach even the most comfortable areas of the Earth every day. One of these phenomena, characteristic of every era and affecting hundreds of thousands of lives every minute, is drought. This

Causes of drought

Drought is characterized by a prolonged lack of precipitation and consistently high air temperatures, leading to the disappearance of plants, dehydration, hunger and death of animals and people. The reasons are so destructive natural processes were identified in the first half of the twentieth century. And the global climate phenomena themselves are called El Niño and La Niña.

The phenomena to which such touching names were given consist of a long-term temperature anomaly, the interaction of air and water masses, which, with a periodicity of 7-10 years, cause different parts of our planet to literally shudder from the abundance or lack of moisture.

Threats and consequences

In some areas of the Earth, hurricanes, tornadoes and floods rage, while others die from lack of water. These menacing phenomena with children's names, according to many scientists, destroyed powerful ancient civilizations, for example, the Olmecs; in the life of a number of peoples of the American continent provoked the development of cannibalism, which captured Indian tribes during the dry years. Nowadays, a prolonged lack of rain and heat are leading to mass deaths, mainly in Africa, and causing serious damage to the agricultural industry of the North American continent and Europe. Therefore, there is no doubt that for humanity, drought is an occasion to mobilize all its strength, knowledge and other resources in the fight against a not fully understood, but very formidable natural enemy.

Hot summer

Drought in Russia also remains a pressing phenomenon. Every year in the summer months in a number of regions, the Ministry of Emergency Situations introduces a regime due to persistently high air temperatures coupled with an almost complete absence of precipitation, which sooner or later provoke fires over vast areas. Russians remember the year 2010 as a thick smoke screen that stretched for thousands of kilometers. At the same time, forests raged in fifteen regions of the country, destroying trees along with settlements and infrastructure. The damage to the population and the state as a whole was colossal. Residents were suffocating from smoke, and insurance companies were suffocating from fabulous payments.

Agricultural yields were under attack, as well as dairy farming, which faced an acute shortage of feed. It was in 2010 that the drought in Russia marked a new temperature record, set 70 years after a similar abnormally hot summer.

Drought in autumn: threat to winter crops

Drought often takes agriculture by surprise in the fall. It would seem that autumn is a period of rain, the first snow and temperatures that are relatively acceptable for plant life. However, precipitation that does not fall on time often affects the entire crop, the area of ​​which is large. That's why workers Agriculture keep their finger on the pulse even in the fall.

The whole world's problem

Billions of losses, inflation surges, famine, mass death people and animals. All these are the consequences of drought. Every day there are reports in the news about certain examples of abnormal heat without precipitation. Thus, in 2011, residents of China became victims of drought. The flooding, which harmed more than three thousand people, gave way to uncharacteristically unbearable heat. The extreme drop in water levels in the Yangtze River has led to difficulties in navigation and, as a result, has caused damage to many areas of activity. The failed rice harvest created a crisis situation in the agricultural goods market.

More recently, in December 2015, drought literally changed the geographical characteristics of the entire country - in Bolivia, one of the largest lakes, Poopo, was destroyed by continuous heat. Due to the fact that local residents previously subsisted solely on fishing, a significant outflow of population was observed in this region as early as January 2016.

Climate change has had the most significant impact on the African continent. It is from there that alarming news and calls for collection are heard with frightening consistency. The difficult situation with rebels denying the catastrophe and preventing the transfer of food supplies further aggravates the situation. Drought in Africa is a particularly merciless phenomenon. The world community does not ignore what is happening, but a huge number of people die from year to year.

Despite the fact that humanity is making enormous strides towards its power, nature is not yet subject to it, and one has only to put up with its whims, sometimes very cruel. Overtaking the continents one after another, drought confirms this.

Explanatory dictionary of the Russian language. D.N. Ushakov

drought

drought, w. Lack of water in the soil, caused by a long absence of rain during intense heat or dry, hot winds and leading to complete or partial burning of crops and vegetation. Drought is fought with artificial irrigation and other methods.

Explanatory dictionary of the Russian language. S.I.Ozhegov, N.Yu.Shvedova.

drought

And, well. A long absence of rain leads to drying out of the soil and death of vegetation. Worth z.

New explanatory and word-formative dictionary of the Russian language, T. F. Efremova.

drought

and. Prolonged lack of rain in summer, leading to drying out of the soil, poor growth or death of plants.

Encyclopedic Dictionary, 1998

drought

prolonged and significant lack of precipitation, often at elevated temperatures and low humidity air. Causes a decrease in moisture reserves in the soil and, as a result, deterioration in growth, and sometimes death of plants. Control measures: agrotechnical ( special processing soils) and reclamation (irrigation) measures, field-protective afforestation.

Drought

prolonged and significant lack of precipitation, often at elevated temperatures and low air humidity, as a result of which moisture reserves in the soil dry up, which leads to a decrease or loss of the crop. The beginning of a winter is usually associated with the establishment of an anticyclone. The abundance of solar heat and dry air create increased evaporation (atmospheric precipitation), and the reserves of soil moisture are depleted without replenishment by rain (soil precipitation). During wintering, the flow of water into plants through root systems is hampered, the consumption of moisture for transpiration begins to exceed its influx from the soil, the water saturation of tissues decreases, and the normal conditions of photosynthesis and carbon nutrition are disrupted. Depending on the time of year, there are spring, summer, and autumn crops. Spring crops are especially dangerous for early grain crops; summer ones cause severe damage to both early and late grain and other annual crops, as well as fruit plants; autumn ones are dangerous for winter crop seedlings. The most destructive are spring-summer and summer-autumn outbreaks. Most often, outbreaks are observed in the steppe zone, less often in the forest-steppe zone: 2-3 times a century, outbreaks occur even in the forest zone. The concept of agriculture is not applicable to areas with rainless summers and extremely low precipitation, where agriculture is possible only with artificial irrigation (for example, the Sahara, Gobi, etc. deserts).

The arid climate in the USSR is typical for the southwestern and central parts of Kazakhstan, the Central Asian republics (with the exception of high mountain regions), as well as the southeastern part of the European territory of the USSR. The boundaries of the periodic appearance of Z. on the territory of the USSR are difficult to establish, because There are almost no places where it has not been observed. The driest years were 1891, 1911, 1921, 1931, 1936, 1946, 1954, 1957, 1967, 1971. Approximately every 3 years, as a result of grain control, the country loses up to 1.5 billion poods of grain. Most often, Z. affects the Middle and Lower Volga region and the river basin. Ural. The probability of death can be determined in advance only by individual factors. For example, autumn moisture reserves in a meter layer of soil are less than 50% of the long-term average data, indicating an impending lack of soil moisture. If the depth of the snow cover and the moisture reserves in it constitute no more than half of the long-term average, then the probability of snow cover in the upcoming spring period is also very significant.

══To combat soiling, a set of agrotechnical and reclamation measures are used, aimed at enhancing the water-absorbing and water-retaining properties of the soil and retaining snow in the fields. Of the agrotechnical control measures, the most effective is basic deep plowing, especially in soils with a highly compacted subsoil horizon (chestnut, solonetz, etc.). In Northern Kazakhstan and in the steppe regions of Western Siberia, it is advisable to cultivate the soil with flat-cutting tools while preserving the stubble on the field surface. On soils located on slopes, special tillage techniques should be used to regulate surface runoff: plowing across the slope; contour plowing (horizontal); techniques that change the microrelief of the surface of arable land (making holes, micro-limans, intermittent furrows). To reduce moisture evaporation, the soil on fallows and wide-row crops must be kept in a loose state, preventing the formation of a soil crust. For this purpose, harrowing, scouring, cultivation, row-spacing treatment, etc. are used. Of great importance are also techniques for destroying weeds, regulating snowmelt, applying fertilizers, pre-sowing soil preparation and sowing in the most short time. It is effective to combine the sowing of winter crops, which make good use of autumn precipitation and are resistant to spring-summer climates, with the sowing of early spring grains, which require precipitation in the first half of summer, as well as with the sowing of corn, millet, sorghum and other late crops. using precipitation from the 2nd half of summer and withstanding spring frosts relatively easily. In arid areas, the introduction of drought-resistant agricultural varieties plays an important role. plants (see Drought resistance of plants). Among other agrotechnical measures in the fight against climate change, the development of correct crop rotations with clean fallows in dry areas and occupied fallows in better-humidified areas is of positive importance. Pure fallow (with curtains) in arid areas is equivalent to fields with moisture-recharging irrigation. Of reclamation control measures, field protection afforestation, conservation and expansion of water conservation forests are of great importance.

From the first days of the existence of the Soviet state, the party and government have been taking important measures to intensify agriculture. production and land reclamation. After the severe drought of 1921, V.I. Lenin signed a special decree “On the fight against drought,” which talks about the allocation of forests of water-protection and protective significance, the strengthening of sands, ravines, the construction of snow collection strips and fences, etc. Further great work to combat Z. They were provided for at the 17th Party Congress (1934), the February Plenum of the Central Committee of the All-Union Communist Party (Bolsheviks) in 1947, in the Directives of the 19th Party Congress on the fifth five-year plan 1951-55, etc. Of particular importance in the implementation of measures to combat with land, strengthening the material and technical base of agriculture, improving the general culture of agriculture, developing land reclamation work to obtain high and sustainable agricultural yields. crops have decisions of the March (1965), May (1966) plenums of the CPSU Central Committee and the 24th Congress of the CPSU (see Water conservation forests, Land reclamation, Protective forest plantations, Irrigation).

Lit.: Timiryazev K. A., Plant fight against drought. Favorite soch., vol. 2, M., 1948; Dokuchaev V.V., Our steppes before and now, Ibr. works. M., 1949; Izmailsky A. A. How our steppe dried up, Izbr. soch., M., 1949; Droughts in the USSR, their origin, recurrence and impact on the harvest. [Sat. materials], ed. A. I. Rudenko, L., 1958; The struggle for moisture equals the struggle for the harvest. [Sat. materials], ed. P. f. Kotova, Voronezh, 1969; Transformation of nature in the Stone Steppe. [Sat. materials], M., 1970.

I. A. Skachkov.

Wikipedia

Drought

Drought- a long period of stable weather with high air temperatures for a given area and low amounts of precipitation (rain), as a result of which soil moisture reserves decrease and oppression and death of cultivated plants occurs.

The onset of drought is usually associated with the establishment of a sedentary high anticyclone. The abundance of solar heat and gradually decreasing air humidity create increased evaporation ( atmospheric drought), and therefore the reserves of soil moisture are depleted without replenishment by rains ( soil drought). Gradually, as the soil drought intensifies, ponds, rivers, lakes, and springs dry up - the hydrological drought.

During drought, the flow of water into plants through the root systems is hampered, the moisture consumption for transpiration begins to exceed its influx from the soil, the water saturation of tissues decreases, and the normal conditions of photosynthesis and carbon nutrition are disrupted.

Depending on the time of year there are different spring, summer And autumn drought.

• spring droughts are especially dangerous for early grain crops;
• summer ones cause severe damage to both early and late grain and other annual crops, as well as fruit plants;
• autumn ones are dangerous for winter crop seedlings.

The most destructive are spring-summer and summer-autumn droughts.

In mid-latitudes, droughts are most often observed in the steppe zone, less often in the forest-steppe zone: 2-3 times a century droughts occur even in the forest zone. The concept of drought is not applicable to regions with rainless summers and extremely low precipitation, where agriculture is possible only with artificial irrigation (for example, the Sahara, Gobi and others deserts).

Droughts are common in the subtropical zone and in the subequatorial zone, where rain occurs only during the wet season.

In order to raise global awareness, the UN established World Day to Combat Desertification and Drought.

Examples of the use of the word drought in literature.

The centuries-old struggle of Russian agronomy has forged a wonderful, harmonious doctrine of restoring soil fertility, of eliminating the catastrophic fall in yields over the years droughts.

And he will die fighting not for apartheid and not for the white race, but for these morgens, which he calls his land, where there are drought, and floods, and earthquakes, and the loss of livestock, and snakes, which he considers as nonsense as mosquitoes.

Finally there were communities that answered the call drought a change in homeland and way of life, and this rare double reaction signified the dynamic act which, from the vanishing primitive societies of the Afro-Asian steppe, gave birth to the ancient Egyptian and Sumerian civilizations.

The peoples of the Afro-Asian grasslands had to answer the challenge drought, while the peoples of the Asian mountain regions could still evade the challenge.

Drought gave way to the rainy season, a brown river flowed behind the blue river, and our bandeira was never able to achieve its goal, moving from the Southern Cross to the North Star.

Dignam, a victim of apoplexy, lies in the ground, and after a cruel drought, praise the Lord, it finally rained, the barman brought peat, sailed fifty miles or so, and said that the crops did not grow, the fields were withered, they looked sad and stank, whether in the lowlands or on the hills.

You were driven away from your usual places drought, but pathetic strangers who are even weaker than big-eyed dwarfs.

In his opinion, the appearance of such a large number of dingoes near the pasture foreshadowed the imminent onset of a great drought.

If the issue of planting trees and protecting forests, it would seem, is so obvious, and even then the population of the planet is of little concern, then the issues of herbs and plants fighting deserts and droughts, even less often occupy the attention of mankind.

If you think a little, in addition to agricultural products, you can use almost any objects, phenomena, living organisms for homemade moderators: snow, ice, water, sand, salt, sugar, drought, thunderstorm, day, night, onset of winter, bed bugs, etc.

How in drought The ears of corn are thirsty for rain, so the Italians are thirsty for reunification with the empire, - Justinian admonished Munda, Belisarius and many of the military leaders subordinate to them.

Of course, the climate could not help but change during different periods of the Cenozoic, and those lands that are now dominated by a temperate climate have, since the beginning of the Cenozoic era, been successively exposed to intense heat, extreme cold and drought.

Then Turu used known against drought and scarcity of means: sacrifices, spells, walking around the fields with prayers.

Who in drought, asked Opivalo, “drinks half the stream, and then walks through all the fields of our village and sprays them, mind you, with his mouth?”

A few minutes later, Paisley comes up, his hair doused with bergamot oil, and he sits on the other side of Mrs. Jessup and begins the sad story of how in ninety-five in the Santa Rita Valley during a nine-month drought, he and Lumley Chaff Snout made a bet on a silver-trimmed saddle to see who could skin the most dead cows.