Friday, 19 May 2017

Dasht-e-Kavir Desert, Iran


The Dasht-e Kavir, is one of two deserts dominating the region's landscape, is a mix of sand and salt as blinding in its whiteness as it is deafening in its silence. Dasht-e Kavir, is also known as “Kavir-e Namak” and “Great Salt Desert”, is a large desert lying in the middle of the Iranian plateau, around 300 kilometers east-southeast of Tehran. Dasht-e-Kavir desert is approximately 800 kilometers long and 320 kilometers wide, and composed of mud and salt marshes. Millions of years ago, this region was occupied by a salt-rich ocean that covers a small piece of continent in what is now central Iran. As the time passes, the ocean gets dried up, it left behind a layer of salt as much as 6 to 7 kilometers thick.

Therefore, over the time, the layer of salt was buried under a thick layer of mud; however salt has a fairly low density lower than the layer of mud and rocks underneath which the salt layer lay. So it taking place pushing up through the overlying sediment and finally, over millions of years, the salt broke through and formed domes. The salt domes of Dasht-e Kavir are probably some of the best examples of this geological marvel. Thus, geologists have recognized about 50 large salt domes in this region. Some of the domes have been eroded away by wind and rain exposing its cross-section.

However, the desert climate is arid and receives little rain and snow each year, but the surrounding mountains on all side, provide plenty of runoff to create vast seasonal lakes, marshlands and playas. Temperatures can reach 50 °C in summer, and the average temperature in January is 22 °C. Though it looks like a firm surface, the salt crust is only a few inches thick, below which lies soft grease-like mud the Iranians called “Charbeh” that is really difficult to get out of if one were to get stuck. Due to arduous travelling to Dasht-e Kavir, it is very dangerous. The soil is sterile and not appropriate for cultivation. In summer the hot temperatures cause extreme vaporization, which leaves the marshes and mud grounds with large crusts of salt. Heavy storms frequently occur and they can cause sand hills reaching up to 40 m in height. Some parts of Dasht- e Kavir have a more steppe-like appearance.

Dasht-e-Kavir desert is almost uninhabited and only partly explored. Wild sheep, camels, goats and Persian leopards also live in the mountainous areas. Hence, human settling is restricted to scattered oases, where wind-blocking housing constructions are raised to deal with the tough weather conditions. Some live in the hills and the surrounding mountains. Against the odds, oases exist within these desolate environs, home to villages that are sustained by the wells of sweet water that have been part of desert mythology for centuries. Vegetation in the Dasht-e Kavir is adapted to common plant species like shrubs and grasses can only be found in some valleys and on mountain tops. So, the most widespread plant is mugwort. The Persian ground jay is a bird species living in some parts of the desert plateaus, along with Houbara bustards, Persian gazelles, camel, goats, leopards, larks and sandgrouses.

Moreover night life brings on wild cats, wolves, foxes, and other carnivores, the Persian onager and Asiatic cheetah can be seen. Lizards and snakes live in different places in the central plateau. The extreme heat and storms in Dasht-e Kavir cause extensive erosion, which makes it almost impossible to cultivate any lands almost uninhabited and knows little exploitation. Camel and sheep breeding and agriculture are the sources of living to the few people living on its soil. For irrigation, Iranians developed a sophisticated system of water-wells known as qanats. These are still in use, and modern globally used water-revenue systems are based on their techniques.