Changes in the Amazon

Changes in the Amazon

The Amazon rainforest covers a large part of the equatorial zone of South America and contains more species of flora and fauna than any other ecosystem in the world. Trees make up about 70% of the flora of tropical forests. Currently, the Amazon rainforest is disappearing at an alarming rate due to logging and agricultural clearing.

Amazon rainforest

The name Amazonas was given by the Spanish friar Gaspar de Carbajal, the first European chronicler to travel down the river during Francisco de Arellano's expedition in the second half of the 16th century.

It is stated that the boat was attacked by women who, as in the mythology of the Amazon, tried to enslave men to procreate and then kill them.


The Amazon is, together with its Ucayali and Apurímac tributaries, the longest river in the world at 6,872 kilometers in length. It is also the largest and its basin, which covers 7.5 million km 2, is the largest in the world.

The varied rainfall at the headwaters of many of the tributaries of the Amazon contribute large amounts of water to its lower courses.

The rising of the waters is not always inopportune, since the rivers of the region are normally the main communication routes, with the canoe as the most common means of transport. Much of the rich Amazon ecosystem, where the largest number of plants in the world are found, depends on periodic floods that carry nutrients to plants and indirectly to the animals that live in this ecosystem. Almost two thirds of the Amazon rainforest is located in Brazil.


This vast region contains the largest tropical forest on the planet and is home to more than half of the known plant and animal species. In one hectare, 300 different species of trees have been identified and in a single tree up to 650 different species of coleopterans can be located. In this way, the Amazon is the largest biological reserve on Earth. 330,000 indigenous people live in the Amazon rainforest, making up 220 ethnic groups and speaking 180 different languages. These ethnic groups comprise groups of very diverse size, from 140,000 members to just three people. In addition to these tribes, there are still Indians who have not had any contact with civilization.

Weather conditions.

There are few seasonal variations in temperature (28 C the annual average), high precipitation (greater than 2000 mm per year) and high relative humidity (70-80%). Although there are months of scarce rainfall, there is no water stress for the plants due to the storage of water in the soil.

Work Project

Is the environmental change that occurs at the end of the 20th century related to the logging of the Amazon?

Objective: After searching for material on the subject to be able to find out and answer the question posed.

See if deforestation causes climate changes in the Amazon area and nearby regions.


Given that man needs to satisfy his needs and that he lives on a planet that suffers from overpopulation, he must carry out different activities in order to survive, some of which cause negative consequences for humanity itself. Among these activities is the phenomenon of deforestation.


The continental surface of the terrestrial globe is covered in 30% by forests, which constitute the richest ecosystems in both flora and fauna.

Since ancient times, deforestation has been carried out for the practice of agriculture and grazing, but in the middle of the 20th century the rate of deforestation has grown alarmingly, especially in the humid tropical forest areas, putting in danger the future of the biosphere.

It is estimated that South America has lost 37% of its forests, in Asia 42% and in Africa 52% to date.

Deforestation of tropical forests has taken place at the rate of 10-16 million hectares per year for the past two decades and shows no signs of abating.

16% of the entire Amazon rainforest has already disappeared and another 7000 hectares of forest are lost every day, an area of ​​10 to 7 km

The causes are complex and are often interrelated. Largely commercial agriculture plays a role among them.

In Brazil, oil palm and soybean companies have been linked to devastating forest fires and destroyed more than 3.3 million hectares of forest and other vegetation in the state of Roraima in the northern Amazon of Brazil.

The different causes of deforestation are:

The Agriculture:

It is a deforestation factor at two points: direct and indirect.

Direct: Forests are converted to grow commercial crops such as sugar, oil palm, rubber, coffee, cocoa, and tropical fruits.

Indirect: Commercial farms occupy the most fertile and best located land in the valleys, displacing the growing rural population that depends on agriculture for their subsistence, therefore small farmers are expelled and must often choose less fertile and productive lands or to "burn" the forest.

Agriculture also brings with it problems such as: use of chemical products such as fertilizers, pesticides, herbicides that affect the deterioration of the health of workers, contamination of crops, soil, and groundwater.

Cattle raising:

The expansion of cattle raising has been promoted by different organizations. The ranchers occupy large tracts of forest area; they either cut them down or buy the improvements (deforested areas) made by small farmers.

The ecological destruction caused by livestock problems is long-term and often irreversible, because the nutrients in the soil are rapidly depleted, which is also invaded by toxic weeds, and in a few years they must be abandoned.

In Brazil, between 1966 and 1978, 8000 km2 of forests in the Brazilian Amazon were destroyed to make way for 366 cattle ranches with 6 million head of cattle, under the auspices of the Superintendency for the development of the Amazon (SUDAM).

In all things, many farms were unproductive in less than 10 years, because the productivity of artificial grasslands declines, which is why many times the ranchers obtained another part of the forest to cut down.


The logging of high commercial value timber produces fragmentation and loss of biodiversity. Seed trees that have not yet reached cutting age are often exploited, putting the species at risk.

Construction of hydroelectric dams.
They flood vast areas of forest.

Road construction:

Governments promote their construction to favor the export of soybeans and other monocultures and once they are built, they open the forest to sawmills, landless peasants, mining companies and many actors, causing immediate and widespread deforestation. .

Forest plantations.

It is important to highlight the negative role that large forest plantations are playing as a direct cause of deforestation, although it seems contradictory, in this case planting trees causes deforestation.

Faced with all these causes, deforestation causes an environmental change that we see reflected at the level:

1) The Population loses its chances of survival as an autonomous culture or the loss of the community itself. The Amazon has 12% of the population of Brazil and the population density is 10 times lower than the average for the rest of the country.

It reaches between 200,000 and 300,000 people spread across 120 nations and some are among the last uncontacted populations in the world.

For this the forest constitutes their sustenance; It supplies them with edible and medicinal plants (many species have benefits still unknown), bushmeat, fruits, honey, shelter, fire and various other products and around it they build their cultural and spiritual values.

Despite this, there is also a migratory stream seeking to participate in the opening of new agricultural frontiers, which means that the population of the Amazon has grown by almost 40% between 1980 and 1988 and that in the last census it had the higher growth rate and widely exceeding the Brazilian average.

2) The land becomes swampy. When the rains are abundant and there are no roots to absorb the water, it accumulates, causing the rivers to overflow (floods).

3) Flora and fauna disappear and migrate to other places.

Flora: All kinds of plant formations, which are life and constitute a source of life, apart from offering multiple utilities such as energy or industrial raw materials, are disappearing from many scenes of the terrestrial landscape.
Fauna: Animals in the face of food shortage must migrate to other places, taking with them some diseases, for example dengue.
Humanity as a whole is then affected, since deforestation brings about the definitive loss of species, which implies a responsibility that must be assumed by humanity in general.

B) Regional

1) Soil erosion: it is the natural process that continuously wears and destroys the soil and rocks of the earth's crust.
Most erosive processes are the result of the combined action of various factors such as heat, cold, gases, water, wind, plant and animal life.

It is avoided with plantings of herbs and trees that form a strong root system or by extending networks that prevent the loss of rocks and soil.
In lands without altering the soils are protected by the vegetal mantle. When rain falls on a surface covered by grass or leaves, some of the moisture evaporates before the water reaches the ground. Trees and grasses act as windbreaks, and the network of roots helps keep the soil in place against the action of rain and wind.

Agriculture and forestry, urbanization and road construction partially or totally destroy vegetation, accelerating the erosion of certain types of soil.

The soil erodes because it does not have a good root system to support the soil, nor does it receive dead plant matter to regenerate its nutrients.
When a tropical forest is razed, its nutrient-poor soil is at the mercy of erosion, which washes away the thin layer of fertile soil and the soil becomes a brick-like mass, totally unfit for cultivation. which favors the advance of the desert in the areas in which it is close, such as the one that is forming in the heart of the Amazon discovered in 1973 and that since that date has spread impressively and is currently in full development, favored due to the constant oceanic winds that come from the Atlantic to the heart of the Amazon, but human action accelerated this climate change.

2) Pollution of water courses. The water used in agriculture, whether rain or irrigation, is mixed with fertilizers and pesticides, this mixture pollutes rivers, streams and underground streams.

3) Appearance of pests due to the breakdown of the ecological balance. Scientists have found that the diversity that characterized the natural world is declining, thus breaking that balance. Forests fulfill very important functions in climate matters and their disappearance affects humanity as a whole.

This environmental change is also accompanied by climatic changes.

At present, climate change and the issue of climate variability have become a new scientific and social concern.

Living beings, when breathing, consume oxygen from the air, release carbon dioxide. The same happens with any type of combustion, such as gasoline, coal or wood.

In contrast, plants through photosynthesis take advantage of carbon dioxide to produce nutrients and release oxygen. In this way, a balance between both gases is maintained in the atmosphere, which has been practically constant to this day.

However, industrial development has increased the amount of carbon dioxide contained in the air, while the widespread clearing of forests has reduced the amount of oxygen generated by vegetation. This would increase the temperature by 2 ° C in tropical regions, but by 10 ° C in the polar caps, with the consequent melting and rising sea levels and the irreversible flooding of low-lying coastal areas, so that a large amount of land would be covered by the waters and that large numbers of people would have to move to higher places to make their homes.

The Amazon is known as the Green Lung of the world, therefore, when the lungs breathe what they do is consume oxygen from the air and then add carbon dioxide to the environment.

What they mean by these words is that the earth breathes through the world's plants, and that if we destroy rainforests or forests of any kind, we will inevitably die asphyxiated by the lack of oxygen that trees produce.

Video: Changes to Brazilian law threaten the Amazon rainforest (September 2021).