DESERTS

In geography desert is defined as the land area in which rainfall rarely exceeds 250 mm per year and the land is arid.The desert can be considered an ecosystem or biome.

A desert is a biome that receives little rainfall. They have a reputation of having little life, but that depends on the kind of desert, in many there is abundant life, the vegetation is adapted to the low humidity and animals usually hide during the day to preserve moisture. The establishment of social groups in the deserts is complicated and requires a significant adaptation to the extreme conditions prevailing in them. Deserts make up the largest area of ​​the earth's surface more than 50 million square kilometers, occupying nearly a third of it. Of this total, 53% are hot deserts and cold deserts 47%.
Erosion processes are important factors in the formation of desert landscape. Depending on the type and degree of erosion that wind and solar radiation have caused, the deserts have different types of soil: sandy desert is that they are composed primarily of sand, which by the action of the wind shapes the dunes, stony or rocky desert is one whose land is made ​​up of rocks or pebbles (this type of desert is often referred to the Arabic word hamada).

The deserts may contain valuable mineral deposits that were formed in the arid environment, or were exposed by erosion. In the lower zones may form salt flats. Due to the dry deserts are ideal places for the preservation of human artifacts and fossils.

It also defines wilderness as an uninhabited place, not inhabited by humans or barely living at all. By this definition, the deserts are also located in colder climates such as the Arctic or tundra.

Patagonia desert
The Patagonian Desert, also known as the Patagonia Desert or the Patagonian Steppe, is the largest desert in Argentina and is the 7th largest desert in the world by area, occupying 673,000 square kilometers (260,000 mi²). It is located primarily in Argentina with small parts in Chile and is bounded by the Andes, to its west, and the Atlantic Ocean to its east, in the region of Patagonia, southern Argentina. To the north the desert grades into the semi-arid Cuyo Region and the Dry and Humid Pampas. The central parts of the steppe are dominated by shrubby and herbaceous plant species albeit to the west, where precipitation is higher, bushes are replaced by grasses.

Fauna y flora
The burrowing owl, lesser rhea, guanaco, tuco-tuco, mara, pygmy armadillo, Patagonian weasel, puma, Patagonian gray fox, desert iguana, Jumping Cow Spider, and various species of eagle and hawk are a few of the variety of animals living in the region.

En el último tema de science hemos hablado sobre the deserts. Algunos han querido pintar deserts o incluso escribir en inglés sobre ellos. Aquí tenéis lo que hemos hecho.