Soils of Australia: predominant types and natural areas, their features

Australia, as an ancient continent, has not only unique flora and fauna, but also soils. There are relic soils in the country, contrasts are observed in the location of the soils of Australia - on the territory of the mainland you can find both highly moistened and dry soils. Consider the features of the prevailing and most common Australian soils.

Features

The position in the distribution areas of Australia's types indicates that its soils are represented by species that are found in the subtropical, tropical and subequatorial belt. Due to the complex circulation of atmospheric air and fluctuations in the volume of precipitation, the soil zones on the Australian mainland are located concentrically.

Tropical species are located in most of the continent, south of 30 ° latitude they become subtropical. The soil cover also regularly changes from the north, from subequatorial regions, to the south, to subtropical ones.

In the center of the mainland, in semi-deserts and deserts, there are mainly primitive sandy unstructured soils. The Western Australian Plateau consists of gravelly soils and sands. On the plains in the center, there are mainly semi-clay and clay soils. Near the lakes of the Central Basin, the land is saline. In the east, west and north, the deserts turn into semi-desert and savannah red-brown and red.

To the east and north, with increasing humidity and altitudinal zonality, the soils turn into red-yellow to the southeast and southwest - into gray-brown and brown, which near the Great Dividing Range are replaced by red-brown.To the north of 28 ° latitude, mountain lateritic soils are formed. Chernozems are found in mountain valleys. The slopes of the mountains are covered with red and yellow soils, yellow-brown forest soils, mountain peaks - with mountain meadow soils. The map of Australia shows that land suitable for agricultural use takes up to 60%.

What soils are most common in Australia

Despite the variety of soil types, some of them occupy a larger area than others. Consider their location and features.

Red-brown

Red-brown and brown soils stretch alternately from tropical semi-deserts to the west to the Indian Ocean, in the east and north - to savannahs and light forests. According to the mechanical composition, these are clays and loams, red-brown have the characteristic color of red brick. The top layer goes 20 cm deep, consists of minerals and humus.It has a fairly powerful humus layer, similar to chernozem, which is why red-brown soils have a high degree of natural fertility.

The next horizon mainly consists of mineral matter washed out from above, but also contains particles of organic matter, products of processing of earthworms and microorganisms. This layer is lighter in color than the upper one and is usually slightly leached. Then comes the parent rock, mostly loam with a slightly acidic reaction.

Ferralitic red soils

Distributed in the north of the continent, in the zone of constantly wet forests. This type of soil acquires a red color due to the predominant iron oxides in their composition, it has a slightly acidic and acidic reaction. Ferrallitic red soils have a humus layer, which on the territory of the savannas has a thickness of 30-40 cm, contains up to 4% of humus, with a predominance of fulvic acids, but is rather poor in nutrients.

Subtropical ferrallitic krasnozems are characterized by weathering, accumulation of kaolinite, hydrates of iron and aluminum oxides. They are dark red in color, with good structure on rocks with an alkaline reaction, on rocks with an acid reaction they are lighter, brick or red-yellow in color and not so structured. The upper horizon has a finely cloddy structure, loose, breathable.

Sand Stone

About 44% of the territory of the Australian continent is occupied by deserts and semi-deserts. They are located in the tropical and mainly in the subtropical climatic zones.

Desert soils of Australia are diverse: in the center and in the north - red-brown, in the southern part - serozem-like, in the western - desert. The Victoria Desert and the Great Sandy Desert are covered with red sandy soils. S alt licks and s alt marshes predominate in the southwest and near Lake Eyre. Sandy deserts occupy a third of the mainland area.13% of Australia's dry land is rocky deserts. The foothills are occupied by large-stony deserts, alternating with dry river channels. The desert plains are plateaus located no higher than 0.6 km above sea level, they spread mainly in the west and cover 23% of the dry territories.

Brown

Painted in brown, lightening with depth, color, saturated with calcium, the content of which in the upper layer is at the level of 90%. Clay predominates in the composition; brown soils are usually neutral in acidity. Most of this land is fertile, has a deep humus layer.

Brown soils are formed under hard-leaved shrub vegetation and forests with evergreen trees, under forbs of meadows and steppes.

Brown

Characterized by a small thickness of the humus layer, as a percentage of humus it contains 5-7%. Burozems are characterized by normal or slightly acidic acidity in the upper horizons, and slightly alkaline in the lower horizons. The profile is quite homogeneous in terms of the accumulation of nutrient minerals, since in brown soils the predominant type of water regime is leaching.

Application

For the most part, Australian soils are infertile, they are deficient in nitrogen and especially phosphorus, trace elements, even in tropical areas where there is enough rainfall. It is possible to harvest from such soils only after cultivation and constant application of fertilizers, mainly organic ones.

Heat-loving crops of tropical species are grown on land suitable for agricultural use.

Earths formed in humid conditions occupy only 5% of the continent. They are located within the zone, located at a distance of 160 to 640 km from the coast, in the east and southeast.

The most fertile are black soils located in northern New South Wales and southern Queensland. The land is actively used for growing cereals, corn and sorghum, in humid areas, and as pastures in moderately dry areas.

The red-brown and brown soils of New South Wales and Victoria grow cereals, especially wheat, some of which is pasture.

On the Australian continent there are soils of different types, they were formed under the influence of a unique climate, therefore they have both common features with soils of this type on the surface of the planet, and their own characteristics. They are located concentrically, around the central deserts and semi-deserts.

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