What is the savanna and where are they? Savannah of South America

Unfortunately, not many people know what savannas are and where they are. Savannah is a natural zone that occurs mainly in the subtropics and tropics. The most important feature of this strip is the humid seasonal climate with a pronounced change in the season of drought and rain. This feature determines the seasonal rhythm of natural processes here. Ferrallite soils and herbaceous vegetation with groups of separately standing trees are also characteristic for this zone.

Localization of the savannah

Let's figure out more about what savannahs are and where they are. The largest area of the shrouds is in Africa, it occupies about 40% of the area of this continent. The areas of this natural zone are smaller in South America (on the Brazilian plateau, where they are called Campos, and in the valley of the Orinoco-Llanosi River), in the east and north of Asia (the Indochina Peninsula, the Deccan Plateau, the Indo-Gangsai Plain), and in Australia .

Climate

The savannah is characterized by the monsoon-trade wind circulation of air masses. Summer in these regions is dominated by dry tropical air, and in winter - by equatorial wet air. The farther from the equatorial belt, the greater the reduction in the rainy season (from 8-9 months to 2-3 at the outer boundaries of this zone). In the same direction, the amount of annual precipitation decreases (approximately from 2000 mm to 250 mm). For the savannah, there are also small variations in temperature depending on the season (from 15C to 32C). Daily amplitude can be more significant and reach 25 degrees. Such climatic features created a unique natural environment in the savannah.

Soils

The soils of the region depend on the duration of the rain period and differ in the washing regime. Near the equatorial forests, in areas where the rainy season lasts about 8 months, ferralitic soils have formed. In areas where this season is less than 6 months, you can see red-brown soils. On the borders with semi-deserts the soils are unproductive and contain a thin layer of humus.

Savannah of South America

In the Brazilian Highlands, these zones are located mainly in its internal areas. They also occupy the areas of the Orinoco Lowland and the Guiana Plateau. In Brazil there are typical savannahs with red ferrallite soils. The vegetation of the zone is predominantly herbaceous and consists of families of leguminous plants, cereals, and also Compositae. Woody species of vegetation are either not present at all, or are found in the form of individual mimosa species with an umbelliform crown, milkweed, succulents, xerophytes and tree-like cacti.

In the northeast of the Brazilian uplands, a large part of the area is occupied by kaatinga (rarefied forest from drought-resistant bushes and trees on red-brown soils). Branches and trunks of kaatinga trees often cover epiphytic plants and vines. There are also several types of palm trees.

The savannahs of South America are also found in the arid regions of Gran Chaco on red-brown soils. Here, sparse forests and thickets of thorn bushes are common. In the woods there is also an algarrobo, a tree of the mimosa family, which has a curved column and a strongly branching spreading crown. Low forest tiers are bushes that form impenetrable thickets.

Among the animals in the savannah there are a battleship, ocelot, pampas deer, Magellanian cat, beaver, cat pampas, nandu and others. From the rodents, Tuko-Tuko and Viskach live here. Many areas of the savanna suffer from locust invasions. There are also many snakes and lizards here. Another characteristic feature of the landscape is the large number of termites.

African shrouds

Now to all readers, probably, it is interesting: "Where is the savannah in Africa?" We answer, on the black continent this zone practically passes along the contour of the region of moist rainforests. In the border zone, the forests gradually thin out and become poorer. Among the forests there are spots of savannas. The tropical moist forest is gradually limited to river valleys, and in the watershed area, they are replaced by forests whose trees dry out leaves in the dry season, or savannahs. There is an opinion that high-grass tropical savannahs began to form in connection with human activity, as it burned all the vegetation during the dry season.

In areas with a short wet season, the grass cover becomes shorter and sparse. From woody species in the region there are different acacia with a flat crown. These areas are called dry or typical savannahs. In the regions with a longer rainy season, thickets of thorn bushes, as well as hard grass, grow. Such vegetative massifs are called desert savannas, they form a small strip in the northern hemisphere.

The world of the savannah of Africa is represented by such animals: zebras, giraffes, antelopes, rhinoceroses, elephants, leopards, hyenas, lions and others.

Savannah of Australia

Let's continue our topic "What is savannah and where are they", moving to Australia. Here this natural zone is located mainly north of 20 degrees south latitude. In the east are typical savannahs (they also occupy the south of the island of New Guinea). During the wet season, this region is covered by beautiful flowering plants: families of orchids, buttercups, lilacs and various cereals. Typical trees are acacia, eucalyptus, casuarina. Trees with thickened trunks are fairly common, where a stock of moisture accumulates. They, in particular, are represented by so-called bottled trees. It is the presence of these unique plants that makes Australia's savannah a little different, unlike the savannas that are located on other continents.

This zone is combined with sparse forests, which are represented by different types of eucalyptus. The forest of eucalyptus occupies most of the northern coast of the country and a significant part of the island of Cape York. In the Australian savannah, you can find a lot of marsupial rodents: mole, rat, wombat, anteater. In the thickets of bushes dwells echidna. In these regions, you can also see an emu, a variety of lizards and snakes.

The role of savannahs for humans

After we have in detail found out, that such savannas and where they are, it is necessary to tell, that these natural zones play the important role for the person. In these regions, peanuts, grains, jute, cotton, sugar cane are grown. In the arid regions, livestock breeding is quite developed. It is also worth noting that some tree species that grow in this region are considered very valuable (for example, teak).

Despite the greater importance, the man, unfortunately, continues to systematically destroy the savannah. So, in South America, as a result of burning out the fields, many trees die. Large areas of savannah are cleaned from time to time from the forest. Until recently, in Australia, about 4800 square meters of cattle were cleared annually to provide pastures for livestock. Km of forest. Now such events are suspended. Many exotic trees also have a harmful effect on the savannah ecosystem (Nile acacia, Llandata vomiting, Opuntia and others).

Climate change leads to changes in the function and structure of the savannah. As a result of global warming, woody plants suffer greatly. I want to believe that people will soon begin to protect nature.