Sierra Madre del Sur: Location, Relief, Climate, Flora and Fauna

Sierra Madre del Sur It is the southern part of the extensive Sierra Madre mountain range that extends throughout Mexico. Although the western region is the one that most presents a variety of inhabitants as well as fauna and flora, the forests of the Sierra Madre del Sur are rich in small species and plants exclusive to the region.

The Sierra Madre was completely formed approximately 66 million years ago, in a process of creation that lasted about 190 million years. The elevation and creation of all the land that rose to form this mountain range occurred in conjunction with the formation of the Rocky Mountains of the United States.

The shape of the Sierra led to the creation of three different divisions to identify them better: Sierra Madre Occidental, Sierra Madre Oriental and Sierra Madre del Sur. Sierra Madre del Sur is considered one of the most important high mountains in Mexico, in the company of the Mesa del Sur and the mountains of Chiapas.

Location

The geological process that led to the creation of the Sierra Madre left an apparent division into three parts.

The Sierra Madre Oriental owes its shape to several terrestrial movements in the rocks that occurred in the Cretaceous period. In central Mexico, there was a lot of volcanic activity in the past that shaped the mountains of the region.

Sierra Madre del Sur is divided from the rest of the Mexican mountains and has peculiar characteristics of the area, although similar to those of the rest.

Elevation

The southern zone of the mountain range extends for 1000 kilometers in the southern territory of Mexico, from Michoacán to Guerrero, on the Isthmus of Tehuantepec located in eastern Oaxaca. The highest point of the Sierra Madre del Sur reaches almost 4 kilometers above sea level.

This part of the mountain range joins the Transversal Volcanic Axis in central Mexico, but in the west it is divided by the Balsas River, which is then connected to the Tepalcatepec River. There is only one highway that crosses this geographical expansion from Acapulco to Mexico City.

Although separated by a river, the mountains of southern Michoacán and Coalcomán are also considered part of the Sierra Madre del Sur mountain range.

Relief

The deepest part of the Sierra Madre del Sur is delimited by a narrow and discontinuous coastal plain that expands throughout the southwest of Mexico and the Balsas River to the north.

A wide variety of narrow ridges and pronounced valleys with quite a few geological irregularities form the Southern Highlands. Many of the ridges of these mountains reach considerable elevations, and have quite irregular shapes with rocks present in several areas.

Volcanic activity

The rest of the Sierra Madre has enough evidence of past volcanic activity, but the volcanic cover of the Sierra Madre del Sur has been lost over time and no longer has the high presence that it had millions of years ago.

However, in the lower part of these mountains you can find dissected rocks millions of years old. It is perhaps the oldest dissected rock in Mexico.

There are very few flat areas in these mountains, presenting irregularities throughout their territory. To the south of this area of ​​the Sierra Madre there is an abrupt cut that divides this formation and the joint with the ocean. That part of the mountain stands out from the rest and rises over the entire Isthmus of Tehuantepec.

Weather

The climate of the Sierra Madre del Sur is mainly humid and warm. However, this also varies with altitude. The lower areas of the Sierra Madre usually have a relatively hot climate in the day and a little colder at night, the temperature falling to around 22 degrees Celsius.

In the highest areas there are high mountain ecosystems, but it does not become completely cold. The temperature remains temperate and in some areas it is considered semi-cold.

Flora

Orchids

Sierra Madre del Sur presents an exclusive biodiversity of this area, especially in regard to its flora. In all its extension there are 350 different species of orchids unique to this part of the mountain, which can not be seen anywhere else in the world.

Coniferous trees

It mainly presents a gigantic expanse of coniferous trees, such as the pine oak forests of Sierra Madre del Sur. This forest extension has an expansion of approximately 61,000 square kilometers, being the main habitat of hundreds of plants and small animals exclusive to the region.

This forest expands along the entire coast of Mexico and occupies almost the entire Sierra Madre del Sur.

The most common plants in the region are oak forests, cloud forests, pine-oak forests and fir forests. However, its frequency changes depending on the elevation and rainfall.

Each type of tree grows at different altitudes, between 1900 and 3000 meters high in relation to sea level. The forest is categorized as a subtropical conifer ecoregion and is one of the most extensive forest expansions that can be found throughout the Mexican territory.

Fauna

Sierra Madre del Sur presents a great biological variety in its complex rock formations.

Butterflies, beetles and reptiles

This area has one of the most diverse populations of butterflies and beetles in all of Mexico. In addition, it has a large number of unique reptiles with its exclusive species of toads, frogs and salamanders.

Mammals

The mammals of Sierra Madre del Sur are similar to those of the western mountain range, but also have exclusive species of bats, mice, skunks and shrews.

Birds

The region is especially rich in bird species: it has unique species of orioles, eagles and nutcracker birds.

All this makes Sierra Madre del Sur one of the richest biogeographical zones in the world.

References

1. Sierra Madre Mountain System, Henry J. Bruman George C. Engerrand, (n.d.). Taken from Britannica.com
2. Mexico, Gordon R. Willey Michael C. Meyer Howard F. Cline Angel Palerm Ernst C. Griffin Henry Bamford Parkes, February 3, 2018. Taken from Britannica.com
3. Sierra Madre del Sur pine-oak forests animal and plant species, (n.d.). Taken from globalspecies.com
4. Sierra Madre del Sur - Physiographic Province. (n.d.). Taken from paratodomexico.com
5. Sierra Madre del Sur pine-oak forests, (n.d.). June 24, 2017. Taken from Wikipedia.com
6. Sierra Madre del Sur pine-oak forests, (n.d.). June 24, 2017. Taken from Wikipedia.com