We explain what mountains are, how they are formed and the flora and fauna they present. Also, what is its importance and the highest mountains in the world.
What are mountains?
Mountains are natural elevations of the earth's surface. They are characterized by having altitudes significantly higher than surrounding areas and steep slopes.
Some mountains appear as individual isolated elevations and stand out for their great height compared to their lower altitude surroundings. Others are part of extensive mountain belts called mountain ranges. Mountain ranges can be made up of hundreds of mountains and be thousands of kilometers long.
The mountains of planet Earth were formed by the movement of tectonic plates. over different geological times. The collision and thrust of two tectonic plates produces the deformation of the crust and the elevation of mountains.
Tectonic forces cause magma to rise from the interior of the planet and come out to the outside in the form of an eruption. For this reason, most mountain ranges are also formed by volcanoeswhich are a specific form of mountainous relief.
Mountains play an important role in the water cycle: snow and ice accumulate at the top of the mountains, which melt in the hot months and give rise to most of the planet's rivers.
See also: Plateaus
How are mountains formed?
The process of mountain formation is called orogenesis. Orogenesis can be produced by the collision and thrust of two oceanic plates, one oceanic and one continental, or two continental plates.
- When two ocean plates collide and push each other, rises form in the crust of the sea. If they rise above the water surface, mountain arcs and volcanoes form in the ocean. The Aleutian Islands, near Alaska, are an example of this type of formation.
- When an oceanic plate and a continental plate collide and push each other, mountain ranges form at the edges of the continents.. The thrust of the plates causes one to slide under the other (a process called subduction) and that the plate that remains above folds and forms mountains and volcanoes. The Andes mountain range is an example of this type of formations.
- When two continental plates collide and push each other, extensive, high mountain ranges are formed.. Since neither plate manages to slide under the other because they have a similar weight and density, a greater collision occurs than in the other cases and the orogeny is much more important. The Himalayan mountain range is an example of this type of formations.
Structure of a mountain
The mountains are composed of the following structure:
- Foot or base. It is the lowest sector of the entire mountain structure.
- Summit, peak or cusp. It is the top of the mountain. This is the most prominent feature and the one that establishes its altitude in meters above sea level.
- Hillside or skirt. They are the lateral and inclined portions of the mountain that connect the foot to the top. They can have slopes of different inclinations.
One way to tell if a mountain is young or old is through its shape. If it has a pointed top and steep slopes, then it is probably a young mountain. On the contrary, if it has a rounded top and slopes with a gentler slope, it is likely that it is an old mountain that has spent millions of years subjected to erosion.
Mountain climate
The climates mountains depend especially on altitude. The temperature decreases as altitude increases, so the highest areas of the mountains tend to also be the coldest. For this reason, the tops of the highest mountains are always covered with ice, since it is cold there all year round and the available water and moisture freezes.
When the altitude is lower, the availability of heat in the atmosphere is greater and temperatures increase. For this reason, the bases of mountains always have a higher temperature than the tops.
Flora and fauna of the mountains
The vegetation of the mountains varies depending on the climate and geographical location, but usually occurs in a staggered mannerthat is, it changes its characteristics as the height increases.
On the floors near the base, the vegetation is usually more abundant and diverse, since the temperatures are higher than at the top. As height is gained, the most cold-resistant plant species predominate. In this way, the vegetation loses size, the trees disappear and only grasses and bushes survive. Once a certain height is exceeded, where the cold is already very extreme, the vegetation disappears completely.
The fauna of the mountains also obeys the altitude and is mainly concentrated in the low and medium elevation portions, where there is more vegetation to provide shelter and sustenance and greater availability of oxygen.
In the more leafy regions, it is possible to find large predators, such as pumas, bears or wolves. In the mountains of the warmest areas of the planet, primates and jungle cats can be found.
As altitude is gained, climatic conditions limit the growth and development of animals, and once very extreme altitudes are reached, the fauna almost completely disappears, with the exception of some insects and birds.
Why are mountains important?
Mountains are important because they are part of the climate and hydrological dynamics of the planet, and they can also reduce the intensity of natural disasters.
- Climate dynamics. Mountains influence atmospheric patterns by acting as physical barriers that alter air circulation and the distribution of rainfall on the planet. In addition, they condition the temperature and cause the amount of heat in the atmosphere to be lower at higher altitudes.
- Hydrological dynamics. Mountains are essential sources of fresh water. The thaws that occur in the mountains feed rivers and streams that are vital for the supply of billions of people in the world. The melting of snow and glaciers in the mountains represents a very important freshwater reservoir for the hydrological cycle and for the supply of drinking water in the future.
- Natural disasters. Mountains act as buffers against certain natural disasters, reducing the speed and intensity of extreme weather events such as tropical storms and hurricanes. However, Mountain areas are prone to natural disasters such as earthquakes and volcanic eruptions, which can cause great damage to nearby populations.
The highest mountains in the world
The highest mountains in the world are:
- Mount Everest. It measures 8,846 meters high and is the highest mountain on the planet. It is located on the border between Nepal and China, in the Himalayas.
- Mount K2. It measures 8,611 meters high. It is located on the border between Pakistan and China.
- The Kangchenjunga. It measures 8,586 meters high. It is located between India and Nepal.
- The Lhotse. It measures 8,516 meters high. It is located in Tibet, on the border between China and Nepal.
- The Makalu. It measures 8,463 meters high. It is located in Tibet, on the border between China and Nepal.
The highest mountain in America is Aconcagua, with a height of 6,961 meters, and is located in the Andes mountain range. The volcano is also located there Eyes of the Saladowhich is the highest on the planet, at 6,891 meters.
References
- Adamuz, J. A. (2023). Myths, beauties and dangers: portraits of the highest mountains in the world. National Geographic Spain. https://viajes.nationalgeographic.com.es/
- Aquae Foundation. (sf). How are mountains formed? https://www.fundacionaquae.org/
- Tarbuck, E. and Lutgens, F. (2005). Earth Sciences. An introduction to physical geology. Pearson Education.
