Savannah is one of the most popular landscapes of the African continent. At the same time, the savanna is present not only in Africa, but also on the South American continent, in Australia and even in Asia - in the subequatorial zone.
Like the inhabitants of the steppe, the inhabitants of the savannas have to adapt to difficult climatic conditions.
Savannah characteristic
Its features are as follows:
- A life flora savannas is directly dependent on weather conditions.
- During the drought, the landscape loses its colors, the grass becomes dry.
- Vegetation is adapted to constant heat and lack of moisture.
- Herbs grow in tufts.
- The waxy leaves are narrow and dry.
- Many species contain essential oils in abundance.
- The main representatives of the flora are cereals, bushes and trees are much less common.
Savanna grass
Herbs of the plant world of the savannah mainly hard-skinned grasses, there are also perennials, and during periods of rain, when the area is subject to flooding, even sedges grow here. Lichens and mosses are very rare, they can only be seen on rocks.
Of the cereals for this African landscape, the most characteristic elephant grass. The plant got its name due to the fact that it is a favorite delicacy of elephant giants. In the rainy season, this grass can grow up to 3 meters in height, and in dry times, ground shoots dry out, often dying from fires. But due to the fact that root system remains alive, in wetter conditions the elephant grass grows back. The shoots of this plant are often used by locals for food.
Bermuda Grass (Pig Finger) forms a dense carpet, grows in open areas, constantly exposed to threats - floods, animal grazing, fires. However, the plant has adapted well to survival in difficult conditions: roots up to 1.5 meters long go deep underground, finding life-giving moisture there. The plant is considered a weed, which is very difficult to fight without special equipment, but at the same time, it very effectively protects the soil from erosion and serves as food for many animals, including sheep.
savanna trees
More often savannah trees are stunted, often vines twine around them.
Most often you can see the famous baobab, a tree with a thick trunk over 29 meters high. It has a spreading crown. This giant is also called the monkey tree, because these primates love to feast on its fruits.
The flowering period takes several months, but the life of each flower is fleeting, just a single night. pollinate the plant the bats. A thick trunk protects the plant from fires, which are not uncommon in the savannah, and is also able to hold moisture accumulated during the rainy season like a sponge for a long time. The length of the roots of this tree often reaches 10 meters.
A person widely uses the baobab in his activities, eating leaves for food, making paper, cloth and rope from the bark, and the substance obtained from the seeds of the tree is a powerful antidote.
oil palm- another representative of the plant world of the savannah, has a long lifespan, from 80 to 100 years, palm wine is obtained from its juice, and the pulp of the pericarp is used in the production of soap.
Mongongo. This is a plant of the Euphorbiaceae family, reaching a height of 30 m. It has palmately dissected leaves and flowers collected in inflorescences. The fruits are actively eaten by the natives. This tree can live in the savannah due to its long roots that go deep into the soil, as well as the ability of the trunk to absorb and retain moisture.
acacia. Acacia savannas look amazing, on which several species of this tree grow:
- whitish;
- Senegalese;
- twisted;
- acacia giraffe.
The plant has a slightly flattened crown shape, therefore it is often referred to as umbrella-shaped. Thanks to such a flat and wide crown of acacia, it creates a shadow under which herbs grow, hiding from the scorching sun. Acacia Senegalese - a small tree, a representative of the legume family, it reaches a height of no more than 6 m, while the trunk diameter is about 30 cm. This acacia has thorns. The benefits of the tree are great: accumulating nitrogen, like other legumes, the Senegal acacia enriches poor soils, and its pods and leaves are absorbed by the savannah fauna.
Twisted acacia well withstands both heat and drought. Its wood has found application in furniture production and construction.
High-quality furniture is made from acacia wood, which is distinguished by an expensive price, and the bark is actively used in industry due to the adhesives it contains.
Persimmon loquat- a representative of the African savannah, this is a plant from the Eben family, a deciduous tree whose bark is painted gray. The average height of the trunk is no more than 6 meters, but some trees manage to grow up to 25 meters. It has dark green leaves and blooms during the rainy season. cream flowers, fruits appear only on female trees, they gradually ripen, changing color from light yellow to purple.
Kombretum krasnolistny grows near rivers, the average tree height is from 7 to 10 meters, the crown is dense. The roots are long, the fruits are poisonous. The leaves of the plant are used as food by giraffes, and parts of the tree are used by humans for industry and medicine.
Most often, trees grow singly, less often - in small groups. In the savannahs of Brazil, you can often find real forests, although they are rare. Herbaceous and semi-shrub cover here is about a meter.
A clear division into two seasons - winter dry and summer rainy - is the main feature of the climate to which the savannah vegetation has learned to adapt.
Savannahs are dominated by herbaceous vegetation. Most of the African savanna is located in Africa, between 15 ° N. sh. and 30°S sh. Savannahs are located in countries such as: Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Benin, Nigeria, Cameroon, Central African Republic, Chad, Sudan, Ethiopia, Somalia, Democratic Republic of the Congo, Angola, Uganda , Rwanda, Burundi, Kenya, Tanzania, Malawi, Zambia, Zimbabwe, Mozambique, Botswana and South Africa.
There are two seasons in the African savanna: dry (winter) and rainy (summer).
- The dry winter season is longer, lasting from October to March in the Southern Hemisphere, and from April to September in the Northern Hemisphere. During the whole season, only about 100 mm of precipitation falls.
- The rainy summer season (rainy season) is very different from the dry season and lasts a shorter amount of time. During the rainy season, the savanna receives between 380 and 635 mm of rain per month and it can rain for hours without stopping.
Savannah is characterized by grasses and small or scattered trees that do not form a closed dome (as in), allowing sunlight to reach the ground. The African savanna contains a diverse community of organisms that interact and form a complex food web.
Healthy, balanced ecosystems are made up of many interacting ecosystems called food webs. (lions, hyenas, leopards) feed on herbivores (impalas, warthogs, cattle) that consume producers (herbs, plant matter). Scavengers (hyenas, vultures) and decomposers (bacteria, fungi) destroy the remains of living organisms and make them available to producers. Humans are also part of the biological community of the savanna and often compete with other organisms for food.
Threats
This ecoregion has been significantly harmed by humans in many ways. For example, local residents use the land for grazing, as a result of which the grass dies and the savannah turns into a barren, desert area. People use wood for cooking and create problems for environment. Some also engage in poaching (hunting animals illegally), which leads to the extinction of many species.
To restore the damage caused and preserve the natural environment, some countries have created nature reserves. national park Serengeti and nature reserve The Ngorongoro are a UNESCO World Heritage Site.
The African savannah is one of the largest wild habitats in the world, it covers almost half the area of the continent, about 13 million km². If it were not for the efforts made by people to preserve the savannah, a large number of representatives of the flora and fauna of this corner of nature would have already become extinct.
African savannah animals
Most savannah animals have long legs or wings that allow them to migrate long distances. Savannah is an ideal place for birds of prey such as hawks and buzzards. The wide open plain gives them a clear view of their prey, the rising hot air currents allow them to soar above the ground with ease, and the sparse trees provide an opportunity to rest or nest.
The savannah has a large species diversity of fauna: the African savannah has become home to more than 40 different species of herbivorous animals. Up to 16 different herbivorous species (those that feed on tree leaves and grass) can coexist in one area. This is possible due to everyone's own eating habits. separate species: they can graze at different heights, in different time days or years, etc.
These various herbivores are food for predators such as lions, jackals, and hyenas. Each carnivorous species has its own preferences for living in the same territory and not competing for food. All these animals depend on each other, occupy a certain place in the food chain and provide balance in the environment. Savannah animals are in constant search of food and water. Some of them are listed below:
African bush elephant
The Senegalese acacia is a small thorny tree from the legume family. It grows up to 6 m in height and has a trunk diameter of about 30 cm. The dried juice of this tree is gum arabic - a hard transparent resin. This resin is widely used in industry, cooking, watercolor painting, cosmetics, medicine, etc.
Many wild animals feed on the leaves and pods of the Senegalese acacia. Like other legumes, these trees store nitrogen and then enrich poor soils with it.
Baobab
Baobab is found in the savannahs of Africa and India, mostly near the equator. It can grow up to 25 meters in height and live for several thousand years. During the rainy months, water is stored in a thick stem, with roots up to 10 m long, and then used by the plant during the dry winter season.
Almost all parts of the tree are widely used by the locals. The bark of the baobab is used to make cloth and rope, the leaves are used as spices and medicines, and the fruit, called "monkey bread", is eaten pure. Sometimes people live in the huge trunks of these trees, and representatives of the Galagidae family (nocturnal primates) live in the crowns of the baobab.
bermuda grass
This plant is also called pig finger. Bermuda grass is widely distributed in warm climates from 45°N. up to 45°S It got its name from an introduction from Bermuda. Grass grows in open areas (pastures, open forests, and gardens) where frequent disturbances to the ecosystem occur, such as animal grazing, floods, and fires.
Bermuda grass is a creeping plant that forms a dense carpet when it touches the soil. It has a deep root system, and in drought conditions, the roots can be underground at a depth of 120-150 cm. The main part of the root is at a depth of 60 cm.
Pigtail is considered a highly invasive and competitive weed. Few herbicides are effective against it. Before the advent of mechanized farming, Bermuda grass was the worst weed for farmers. Nevertheless, it saved a huge amount of agricultural land from erosion. This plant is very nutritious for large cattle and sheep.
elephant grass
Acacia twisted is a tree from the legume family. Its homeland is the African savanna of the Sahel, but the plant can also be found in the Middle East. It is known that the plant can grow in highly alkaline soil, and withstand dry and hot environmental conditions. In addition, trees that reach the age of two are notable for slight frost resistance.
The wood of these trees is used in construction and furniture is made from it. Many wild animals feed on the leaves and pods of the acacia tree. Parts of the tree are used by the locals to make jewelry, weapons and tools, as well as in traditional medicine.
The black locust plays an important role in the restoration of degraded drylands, as the roots of the tree fix nitrogen (the main plant nutrient) in the soil through interaction with symbiotic nodule bacteria.
Acacia sickle-bladed
The sickle-bladed acacia is commonly found in the savannahs of equatorial East Africa, in particular the Serengeti Plain.
This acacia can grow up to 5 m tall and has sharp spikes up to 8 cm long. The hollow spikes can be inhabited by 4 species of ants and they often make tiny holes in them. When the wind blows, the spikes thrown by the ants make a whistling sound.
The life of the entire savanna is directly dependent on its weather. It loses its brightness with every drought, turning into a sea of sultry despondency and dried grass. At the same time, after a few days of rain, nature becomes completely unrecognizable. This article will look at the most common African savannah plants.
Description
Savannahs are found in places where the dry period lasts up to 8 months per year. The powerful bark of very thick, low ones can sometimes reach 30 millimeters or more. It prevents rapid moisture loss and also protects plants from fire. With frequent fires, savannah plants practically do not suffer, only the outside of the bark is charred. The above-ground organs of the bushes burn out during fires, and those located near the surface of the soil form new shoots, thus rising from the ashes. The second feature of the trees is their flattened umbellate or disc-shaped crowns.
Plants also survive drought in another way - they store water. So, trees that have learned to do this on their own have an interesting appearance: very thick branches and trunks, as well as fleshy leaves. These organs are reservoirs in which plants store the moisture they need so much in such harsh conditions.
Cereals
Considering cereal plants, it is worth highlighting elephant grass. It got its name due to the fact that elephants love to feast on its shoots. In those places where the doge season is longer, the height of the grasses reaches three meters. The ground part of the shoot dries out in drought and is very often completely destroyed by fires, while the underground part is preserved, giving them a new life after the rains.
acacia savannas
In Africa, acacia savannas are also often found. Basically it is a whitish, Senegalese, giraffe acacia. Due to its flattened crown, the tree began to be called umbrella-shaped. Adhesives contained in the bark are widely used in industry, while the wood is used to create expensive high-quality furniture.
Baobab
Continuing to talk about savannah plants, it must be said that her calling card It reaches a height of 25 meters, has a thick trunk (up to 10 meters in diameter), as well as a sprawling huge crown. Not so long ago, a giant baobab was discovered in Africa with a trunk diameter of 44 meters, in addition, a height of 189 meters. Such savannah plants are long-lived, in some the age reaches 5000 years. Baobab blooms for several months, while each flower lives only one night. They are pollinated by bats.
oil palm
Savannah plants are quite diverse. Among them there are also. This plant has a life expectancy of up to 120 years. It is worth mentioning that the pulp of its fruits contains about 70% of the oil used in soap making. When the inflorescence is cut, the juice is used to make wine.
Features of the animal world
The plants and animals of the savanna are always interconnected. The plant diversity listed above is food for the bulk of herbivores. The main part of them are antelopes:
- oryx;
- kongoni.
Near the wildebeest, you can always see herds of Grant and Thompson's gazelles and zebras. All herbivores are excellent prey for various predators. Cheetahs, lions, hyenas and leopards maintain balance by being at the top of this food chain.
On different continents, savannas differ in their floristic composition, but are united by the similarity of some features: the presence of the main grass layer with an abundance of xerophilous grasses, as well as the upper rare layer of trees and shrubs that grow singly or in small groups.
13. Match.
14. What scientific hypothesis are the lines of Vladimir Vysotsky devoted to?
“At first there was a word of sadness and longing,
The planet was born in the throes of creativity -
Huge pieces were torn from sushi to nowhere
And islands became somewhere"
1) the search for Atlantis
2) the death of Pompeii
3) continental drift
4) the formation of the solar system
15. Snow avalanches are one of the most formidable and dangerous natural phenomena. Which region of Russia snow avalanches pose the greatest risk?
Republic of Kalmykia
Pskov region
The Republic of Khakassia
Tyumen region
| Objects cultural heritage UNESCO | The country |
| 1) Historic city center of Bruges | A) Romania |
| 2) Palace and Park of Fontainebleau | B) Peru |
| 3) Windmills in the Kinderdijk-Elshout area | B) Mexico |
| 4) Stonehenge | D) Great Britain |
| 5) The ancient Inca city of Machu Picchu | D) the Netherlands |
| 6) Monasteries of Meteora | E) Belgium |
| 7) Agave plantation landscape and ancient tequila factories | G) France |
| 8) The ancient city of Petra | H) Sweden |
| 9) Villages with fortified churches in Transylvania | I) Greece |
| 10) Lapland | K) Jordan |
17. The lines of the tropics and polar circles are the boundaries ...
climatic zones
natural areas
geographical areas
lighting belts
1) Aldan
2) Koryak
3) Kolyma
4) Patomskoe
19. Cactus-acacia savannas - characteristic nature...
1) Ahaggar Plateau
2) Nubian desert
3) Great Artesian Basin
4) Mexican highlands.
20. Pick two settlements, where on January 14 at astronomical noon the lengths of the shadows cast by identical cell towers are equal.
1) Gorno-Altaisk and Tura
2) Orenburg and Moscow
3) Volgograd and Khabarovsk
4) Nalchik and Irkutsk.
21. What is sludge?
1) Intra-water ice.
2) Bottom ice.
3) Ice growths in the form of layers.
4) Bands of water free of ice.
22.Choose a deep sea trench located in a different ocean from the others.
1) Central American
2) Aleutian
3) Yuzhno-Sandvichev
4) Filipino
23. The highest average annual precipitation falls on the western slopes…
1) Ural Mountains
2) Greater Caucasus
3) Sikhote-Alin
4) Verkhoyansk Range.
24. Tourist companies from different regions of Russia have developed advertising slogans (slogans) to attract tourists to their regions. Establish a correspondence between the slogan and the region. Write in the table the numbers corresponding to the selected answers.
| Advertising slogan | Region of Russia |
| 1) We offer a helicopter tour over the amazing Valley of Geysers. You can take a boat trip along Avacha Bay and Pacific Ocean. | a) Astrakhan region |
| 2) Here you can see thickets of blooming lotus and bird nests in the delta of the largest European river. | b) Kaliningrad region |
| 3) Welcome to the "Amber Region", the most western region of Russia! | c) Chukotka |
| 4) Here you can visit the Western and Eastern hemispheres. | d) Kamchatka Territory |
25. What climatic zones(choose from list a-zh) correspond to climatic diagrams 1-5:
a) equatorial
b) subequatorial
c) tropical
d) subtropical
e) moderate
f) arctic
g) subarctic
26. What is the main danger to humans is the emergence of "ozone holes"?
1) Increasing the intensity of ultraviolet harmful to living organisms
radiation.
2) Reducing the intensity of ultraviolet solar radiation, in small
doses necessary for living organisms; expansion of areas of its deficiency.
3) Strengthening the greenhouse effect and global warming.
4) Melting of the Arctic and Antarctic ice due to the increase in incoming solar
radiation.
27. During the construction of a high-rise building of Moscow University in 1953 forclassrooms, furniture was ordered from valuable broad-leaved species (oak, ash,maple). In which of the republics of the USSR was this furniture made?
2) Azerbaijan
3) Uzbekistan
4) Kyrgyzstan.
28. Transfer at the beginningXIXcentury Makarievskaya Fair in Nizhny Novgorod contributed to the rapid development in the city ...
1) shipbuilding
2) iron and steel industry
3) metalworking
4) Automotive
29. Which of the following cities in Russia produces buses?
1) Naberezhnye Chelny
2) Ulyanovsk
4) Golitsyno
30. Which pair of countries are currently experiencing an Ebola epidemic?
1) Congo and Mali
2) Niger and Chad
3) Namibia and Ivory Coast
4) Liberia and Sierra Leone.
TASKS OF THE ANALYTICAL ROUND
Prepare answers to assignments on sheets of A4 paper.
Time allotted for the analysis round - 90 minutes.
Analysis round includes 5 tasks.
Sum of points for all assignments 60 points.
When working on assignments allowed to use:
pencil
ruler
protractor
calculator.
It is not allowed to use:
textbooks
Geographic atlases
reference materials
Internet
Any electronic devices used to transmit, receive or store information (except for calculators).
Exercise 1.
To complete the task, use the topographic map.
1) What does the inscription above the upper frame of the map "Mirtsevsk 55 km" mean?
2) Find a contour line with the maximum value within the depicted territory, indicate its absolute height, location on the map and determine the direction in degrees and the distance from the berghmark on it to the pier (in a straight line).
3) Determine the absolute heights at which the forester's house and the barn are located, which object is located higher and by how many meters?
4) Is the river Sot navigable? How can this be installed? Give its main characteristics: the direction and speed of the current, the width and depth of the channel, the nature of the bottom soil.
5) Which of the three sites, marked on the map with the letters A, B, C, is more suitable for competitions in tourism and orienteering. Name at least two of its benefits.
The maximum number of points is 15.
AT
B
BUT
Scale 1:25 000
The main horizontals are drawn through 5 meters
Task 2.
Desertification is one of global problems humanity. One sixth of the world's population lives in a desertification zone. Especially dangerous is the expansion of the areas of man-made deserts, which appeared as a result of irrational nature management. The same is experienced by the object described below.
Almost the entire territory of this republic Russian Federation located in the arid climate zone. Dry-steppe and semi-desert landscapes of this territory are mainly used as natural pastures. Land is being plowed up for irrigated agriculture. Irrational agricultural nature management leads to general land degradation and desertification. This territory, captured by active desertification processes, is classified as an ecological disaster zone.
Give answers to the following questions:
What region of Russia are we talking about?
What are the reasons for the development of desertification (specify at least 3 reasons)?
Specify no more than 5 negative environmental and socio-economic consequences of the problem.
Task 3.
Russia is the country where the law was first discovered geographic zoning. You can get acquainted with various natural areas by traveling around our country by train. You are offered four railway tourist routes, from which you need to choose one that crosses the largest number of natural areas. Draw a table on the answer sheet and mark in the appropriate cells with crosses or checkmarks the natural areas that each route crosses.
Determine the route that passes through the largest number of natural areas. Which pools largest rivers European Russia intersect this route if we assume that the railroad route is close to a straight line connecting its end points? List the names of these river basins in the order the train travels from north to south.
| natural area | Route |
|||
| Saint Petersburg - Astrakhan | Vorkuta – Rostov-on-Don | Novy Urengoy - Kurgan | Arkhangelsk – Saratov |
|
| Tundra | ||||
| forest tundra | ||||
| Taiga | ||||
| Coniferous-broad-leaved (mixed) forests | ||||
| broadleaf forests | ||||
| Forest-steppe | ||||
| Steppes | ||||
| semi-deserts | ||||
| Total natural areas along the route | ||||
The maximum number of points is 10.
Task 4.
Natural heritage is unique objects nature, which have a special value for the region, country, world. Some natural objects are considered as natural heritage of all mankind and are under the protection of UNESCO. This is a heritage that we must know, protect and preserve.
Determine the description of the natural objects included in the UNESCO World Heritage List, the country where they are located. Describe what makes these objects unique (no more than 3 positions). Is there an impact of human activity on nature?
BUT. Unique natural object located in the Arctic zone, near the border of two oceans and actually between two continents. It was first mapped by explorer I. Lvov in the early 1700s. This island bears the name of a famous navigator, one of the founders of the Russian Geographical Society.
B. The beauty of the nature of these mountains is sung by such famous poets like A.S. Pushkin and M.Yu. Lermontov. Part of this mountain range, located to the west of the highest peak, is recognized as a World Natural Heritage Site.
Savannahs and deserts are vast territories of our planet, which differ sharply from each other in flora and fauna and are similar only in a hot climate. Zones of equatorial forests on Earth are replaced by savannahs, they turn into semi-deserts, and already semi-deserts are replaced by deserts - with quicksand and a minimum of vegetation. These territories are of great interest to researchers; many expeditions go there every year to study the natural diversity of our planet. What are savannas and deserts and how they differ from the steppes of the temperate zone, you will learn on this page
What are savannahs and what plants grow in them
Savannas are grassy plains located between tropical forests and deserts. They differ from the steppes of the temperate zone in that trees and shrubs are found everywhere in them, sometimes single, and sometimes forming entire groves. So the savanna can also be called a forest-steppe. Acacias, baobabs and cereals grow there. There are savannahs in America, where they are called "llanos", and in Africa, and in Asia.
The main feature of the savannas is that the rainy and dry seasons are clearly distinguished here.
As you can see in the photo, the savannas in different seasons look completely different. Both plants and animals have adapted to many months of drought. The leaves of savanna plants are usually narrow, they can be rolled up into a tube, and sometimes covered with a waxy coating. In the dry season, the vegetation freezes, and numerous animals - zebras, buffaloes, elephants - make long migrations (transitions from one place to another) in search of water and food. And in the rainy season, on the contrary, the savannah is full of life.
Candelabra spurge grows only in Somalia and eastern Ethiopia. Its branches resemble a candelabra, that is, a candlestick for several candles. The tree reaches a height of 10 m, and even elephants find shelter in its shadows.
Speaking of what grows in the savannah, one cannot fail to mention the favorite delicacy of giraffes - acacia. These trees have a broad, flat crown that provides shade for the leaves below, preventing them from drying out. These are quite tall trees, and their leaves and branches serve as food for the inhabitants of those places. Acacia is very fond of giraffes - the tallest land animals on our planet. With a growth of 6 m, a third of which is the neck, the giraffe finds plant food for itself at a height where it has no competitors. And the long 45-meter tongue allows it to capture the farthest branches.
Savannah perennial grasses have underground shoots, and the roots grow and form a woody tuberous body. It persists in the dry season and produces new shoots as soon as the wet weather sets in.
Interesting facts about deserts and desert plants
Deserts occupy almost a fifth of the land. All of them, except for the Arctic and Antarctic, occur in a hot, dry climate. Not all lands in the deserts are bare and dull. There are also xerophyte plants, the roots, stems and flowers of which are able to extract and conserve water, hide from the merciless sun and catch its life-giving rays. And some of them - ephemera - grow, bloom and fade in just a few weeks under favorable conditions for life.
The desert saxaul plant can be a shrub or a small tree. Its roots go into the ground at 10-11 m. These plants form desert-tree thickets - saxaul forests.
Tamarisk grows along the banks of rivers, but also lives in deserts, salt marshes and sands. This plant is widely used to fix moving sands in forest plantations and in desert and semi-desert zones, especially on saline soils.
Camel's thorn is a thorny shrub. It is helped to successfully exist in the sands by a long root system, going to a depth of 3-4 m, where the water is. And the plant itself rises above the ground by no more than 1 m.
Ephedra is found in dry areas around the world. Its leaves are small, scale-like, which reduces water loss, and its roots are strong and long. This is poisonous plant, but for several thousand years it has been used to make medicines for asthma and other diseases.
One of the most interesting facts about deserts - the presence of magnificent oases in these seemingly dead territories. An oasis in the desert is a place where The groundwater and form a spring or lake. Birds fly there to drink, and they spread seeds, from which trees, grasses and shrubs later grow. As long as there is water, the oasis also lives. It can be a small pond with a few palm trees or a whole city with rich agricultural land. Thus life flourishes among the sands.
Deserts are not only sandy, but also rocky, and rocky, and saline. Their vegetation serves as food for animals, even large ones like camels. They feed on branches and leaves of saxaul, desert acacia, although the leaves of these plants are small and hard. The main delicacy of the “ship of the desert” is camel thorn. Its branches are prickly and inedible, but the leaves are very juicy and tasty.
Desert plants cacti and their photos
Among the plants of the southern deserts and semi-deserts, cacti stand out. They do not have leaves, but there is a thick stem in which reserves of water and nutrients are created. Such plants are called "succulents". Desert cacti are very diverse: among them there are both large, like trees, and medium, like shrubs, and low, like grasses.
Cacti are native to North and South America and can be found from Canada to Patagonia. Therefore, cacti are a sign of American deserts and semi-deserts. Cacti in the desert differ from other succulents in that they have areoles, that is, modified buds with scales that have turned into spines and hairs or only spines.
Pay attention to the photo: cacti in the desert sometimes form real cactus thickets, which are not so easy to get through. In Australia, they even erected a monument to the moth. The fact is that a South American cactus catastrophically bred there in the 1920s, and only a compatriot moth could cope with it.
The plant of the desert cactus saguaro, or giant carnegia, reaches a height of 1.5 m by the age of 20. But it continues to grow, and cacti 7-8 m high have side shoots that look like hands. The cactus has nowhere to hurry, because average duration his life is 75 years, but there are also 150-year-old centenarians. They grow up to 15-20 m, weigh about 10 tons, and 90% of their weight is water. The roots of the saguaro are short, but very tenacious, so that he is not afraid of any hurricanes.
In the Galapagos Islands, off the coast South America, you can see tree-like cacti reaching a height of 12 m. Surprisingly, these trees are cacti. These are prickly pear, which most often grow as shrubs on the mainland.
