In the school curriculum of geography, lowlands pass, studying their features, geographical location, topography, climate, and inland waters. Particularly noteworthy is the part of the territory that is located on the South American mainland - the Amazonian lowland. On the map, finding her work is not difficult, since it is the largest on the planet. The lowlands in the west are the Andes mountain system, in the east it reaches the shores of the Atlantic Ocean. And in the north it borders on the Guiana plateau, in the south it collides with the Brazilian plateau.
The Amazonian lowland stands out not only for its size, but also for its features. This territory can be called the kingdom of impenetrable jungle and swamps. Some animals inhabiting this area are very dangerous. However, more on that later.
Description Plan
In order to describe the Amazonian lowlands, you need to use a plan, an example of which is shown below. With its help, you can make a complete description of a geographical object.
Plan:
- A brief description of the lowland.
- Geographical position.
- Territorial division.
- Inland waters.
- Climate.
- Vegetation and soil.
- Animal world.
- Civilization.
So, the plan is drawn up, you can immediately begin to describe this lowland.
a brief description of
The Amazonian lowland (on the map of the Southern Hemisphere) is a vast lowland area of South America. And, as already mentioned, the largest on the planet. Its area exceeds 5 million square meters. km
The lowland was formed as a result of sediment of friable mineral material from the bottom of the planet’s most watery river, the Amazon, on land. This process (accumulation) has been going on for many years. The Amazonian lowlands completely occupy the river basin. The average elevations of this geographical area are from 100 to 300 m above sea level.
Where is the Amazon lowland?
The Amazonian lowland is located in the trough (syneclise) of the South American platform. This deflection is filled with rocks of the Paleozoic period. In the north and in the south, the lowland approaches crystalline rocks of shields and gradually rises to the plateaus.
Where is the Amazon lowland on the map? In order to answer this question, you first need to find mainland South America. There, between the meridians of 49 ° and 78 ° west longitude and the parallels of 5 ° north and 19 ° south latitude, there is a vast territory densely indented by river beds. As a rule, on the maps the lowland is highlighted in greenish color, so it will be easy to find its borders.
Territorial division
Geographically, the Amazonian lowland is divided into two regions. These are Western and Eastern Amazonia. The border between them is the large tributaries of the Amazon River: the right - Tapajos and the left - Rio Negro.
Western amazonia
A flat and flat relief is represented in the west by the Amazonian lowland. Altitude can vary slightly throughout, but this figure does not exceed 100 m. It expands significantly from north to south, reaching up to 1,600 km.
Inland waters
Most of the large rivers flowing along the Amazon lowland originate in the foothills of the Andes. They get food by melting snow in the mountains. In addition, they are fed by groundwater. The rivers of Western Amazonia are distinguished by their complex flow regime and full flow. The valleys have high floodplains, often flooded. During the flood period, water in rivers can rise by 10-15 m, and the channel spills several tens of kilometers. Some water currents flood their shores for several years. The river beds are meandering with muddy water. Wetlands are often found. The largest and most significant rivers of the region are Napo, Maranion, Ukayali, Beni, Yapura-Kaketa, Isa Putumayo.
Climatic features of Western Amazonia
The geographical location of the Amazonian lowlands directly affects the climate. Its western part lies within the equatorial belt. Here, the highest humidity and high air temperatures. The average annual rainfall is 2,500–3,500 mm. This is the highest rate of the planet. Thunderstorms take place here daily in the afternoon. Summer does not stop on this territory all year round, average temperatures are + 28 ° ... + 30 ° . Humidity is in the range of 80-90%, at dawn it can reach a maximum of 100%.
Vegetation
The vegetation is dominated by moist equatorial forests - selva and gileas. Areas of these thickets that are prone to frequent flooding due to river spills are called igapos. Often the entire floodplain is flooded, and only tall trees are visible above the water. Very often, seeds of vegetation are transported over water over long distances. When the water level drops, they settle and sprout on their own.
Soils are podzolized lateritic, often have an orange color due to the emergence of aluminum and iron oxides on the surface. The forests of Western Amazonia are high (tree crowns reach 30-35 m, the highest representatives - up to 60 m), inaccessible, shady, impassable, respectively, almost untouched by man.
Animal world
The geographical position of the Amazonian lowlands has its own characteristics. For example, on the western side there is increased humidity. That is why those animals that live on trees to a greater extent live on this territory. These are sloths, monkeys, possums, anteaters and endemic people of the region - tenacious tailed bears from the marsupial family. Their feline arboreal in the forests of Amazonia can be found spotted jaguar, gray puma and little jaguarundi.
A humid climate is an ideal place for insects, reptiles, amphibians. Western Amazonia is the most favorable place on the planet for different types of snakes. The most dangerous representatives live here: zhararaka, terrible rattlesnake, asp, thorn-bushmaster. But the most popular species of this area are boas, led by the largest snake on the planet - anaconda.
The rivers of the Amazon have a rich wildlife. In addition to commercial fish, alligators and carnivorous piranhas are found in equatorial waters.
Eastern amazonia
The eastern part of the lowland is much narrower. The maximum width is 350 km. This region is more dissected, sometimes crystalline rocks are found on the surface. The Amazonian lowland (the height within 200 m is considered an average) in some places rises to 350 m above sea level from the east.
Water resources
The river valleys are slightly sinuous, deeply cut into the land. The water in them is clear, the flow is fast, rapids and waterfalls are often found. The uniqueness of the watercourses of Eastern Amazonia lies in the unusual color - it is dark blue. Humic acids, which are a product of the decomposition of plants, give this shade. The rise of water in these streams is provoked by heavy rains typical of this region. In addition, ocean waves enter the mouth, which also contribute to the periodic rise in the level of rivers.
Climate of Eastern Amazonia
The eastern region of Amazonia lies within the subequatorial climate zone. Average air temperatures + 25 ° ... + 28 ° . Humidity here is lower than in the western region - 80%. The average annual rainfall is also less - 1,500–2,500 mm. There is a dry period. The geographical position of the Amazonian lowlands is such that the Atlantic part has a great influence on its eastern part. They are largely contribute to the formation of climate. Southeast trade winds bring a long period of droughts to the region. In this regard, the flora of the region is changing.
Flora and fauna
In contrast to the western region with evergreen equatorial forests, the eastern region has deciduous thickets and savannahs. In the region, there are atypical deer-mazams, as well as armadillos and anteaters, which are atypical for this area. A lot of insects, termites, small rodents. A wide variety of birds is characteristic of this region. In Eastern Amazonia, you can meet dozens of different genera of parrots, toucans. The smallest representative of birds - hummingbirds - also lives here.
Studying the vegetation of this region, one can notice how the geographical position of the Amazon lowland affects. It is known that the forests that grow in this area are considered the largest tropical forest on the planet. More than half of such thickets of the planet account for this territory. The ecological problem of this region and the planet as a whole is deforestation. The most serious consequence may be an increase in the greenhouse effect.
Civilization
The Amazonian lowland is a remote region of the planet where civilization is practically absent. The communication lines here pass along the river. Along the shores of the Amazon are only two large Brazilian cities - Manaus and Belen. And from the capital of Brazil to the city of Belem, an asphalt road is laid, the only one for the entire region.
Students in grades 5–7 who need to describe the geographical location of the Amazonian lowlands are encouraged to use this article.