The Precordillera of La Rioja, San Juan and Mendoza is a mountainous area of more than 450 kilometers in length, and ranges from the Sierras Pampeanas to the Cordillera Frontal of Argentina.
It extends from 29º south latitude, on the border with the Puna, to the Mendoza river, and borders the Rodeo, Uspallata, Calingasta and Iglesia valleys. Here are some of the most relevant aspects of this geological province.
characteristics
- The predominant biome in the Precordillera is the semi-desert.
- The climate is arid.
- It has great thermal amplitudes, since the area is furrowed by the Zonda wind, with high temperatures, and this increases the flow of the rivers, inducing seasonal changes.
- The discharge of humidity from the winds coming from the Pacific means that the surface of the Precordillera does not produce snow frequently.
- The average annual wind speed in the area is between 15 and 20 kilometers per hour.
- Average annual rainfall is less than 400mm, - In the Precordillera there are three large transversal rivers: The Jáchal River, San Juan and Mendoza.
- The agricultural practice on the banks of the rivers is very common in the Precordillera.
- One of the most popular economic activities is viticulture; that is, the cultivation of the vine that will be used in the production of wines.
Relief
The Precordillera is distinguished by presenting three large mountain ranges, each with an approximate length of 150 kilometers.
Reviewed from north to south, these groupings are as follows:
1- Northern set: it begins to the south of the Bonete hill and ends a little north of Rodeo, in the town of Angualasto. The Cerro de la Bolsa has the highest altitude of the Precordillera, with 4924 meters.
2- Central complex: it begins to the north of the Sierra Yerba Loca, and continues in a southerly direction on the Alumbre and Blanco and Sierra de la Invernada hills, until it reaches the transversal valley of the San Juan river.
3- Austral group: it ranges from the Sierra de Tontal to the Sierras de Villavicencio and Uspallata, slightly exceeding the altitude of the Mendoza River.
The mountains that make up the Precordillera are parallel blocks, separated from each other by long and narrow valleys. The peaks are peneplains, the product of prolonged surface erosion.
Flora
The Precordillera of La Rioja, San Juan and Mendoza has a xerophilous vegetation; that is to say, it is mainly composed of low bushes, cardones, carob trees, broom and jarillas.
In higher altitude areas the plants are a little smaller and curved. This responds to the natural adaptation of these species to the scarcity of water, low temperatures and gusts of winds.
Fauna
The most predominant species in the Precordillera are the Patagonian mara, chinchilla, guanaco, red fox, puma, vicuña, vizcacha de la sierra and iguanas.
With regard to birds, the Condor, the black heron and the red-legged flamingo stand out. It is also possible to appreciate the presence of rheas in the area.
References
- Arid Andes: Precordillera of La Rioja, San Juan and Mendoza (2011). Recovered from: esb320geografia3.blogspot.com
- Argentina Regionalization (2006). Recovered from: todomonografias.com
- Conti, L. (2016). Precordillera of La Rioja, San Juan and Mendoza, mountainous area. Recovered from: prezi.com
- Furque, G., and Cuerda, A. (1979). Precordillera of La Rioja, San Juan and Mendoza. National Academy of Sciences. Cordoba Argentina. Recovered from: naturalis.fcnym.unlp.edu.ar
- Municipality of La Rioja (2017). Official Website of the Municipality of La Rioja. La Rioja, Argentina. Recovered from: Municipiolarioja.gov.ar.