Zud

A zud or dzud (Mongolian: зуд) is a Mongolian term for a severe winter in which large number of livestock die, primarily due to starvation due to being unable to graze, in other cases directly from the cold. There are various kinds of zud, including white zud, which is an extremely snowy winter in which livestock are unable to find nourishing foodstuff through the snow cover and starve.

One-third of Mongolia's population depends entirely on pastoral farming for its livelihood, and harsh zuds can cause economic crises and food security issues in the country. This natural disaster is unique to Mongolia.

There are different types of zud:

Some traditional methods to protect the livestock from such inclement weather conditions include drying and storing cut grass during the summer months, and collecting sheep and goat dung to build dried flammable blocks called "Khurjun" or kizyak. Dried grass can be fed to animals to prevent death from starvation when zud occurs. The "Khurjun", or blocks of sheep and goat dung, were stacked to create a wall that protects the animals from the wind chills, and keep them warm enough to withstand the harsh conditions. These blocks can also be burnt as fuel during the winter. These methods are still practiced today in the westernmost parts of Mongolia, and areas formerly part of the Zuun Gar nation.

Also because of the semi-permanent structure of the winter shelter for their livestock and the cold, most if not all nomads engage in transhumance (seasonal migration). They have winter locations to spend the winter that is in a valley protected by mountains on most sides from the wind, while in the summer they move to more open space.

Human factors worsen the situation caused by the harsh winters. Under the communist regime, the state regulated the size of the herds to prevent overgrazing. The 1990s saw a deregulation of Mongolia's economy and a simultaneous growth in worldwide demand for cashmere wool, which is made from goat hair. As a result, the number of goats in Mongolia has grown sharply. Unlike sheep, goats tend to damage the grass by nibbling at its roots; their sharp hooves also damage the upper layer of the pasture, which is subsequently swept away by the wind. This leads to desertification.

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Wikipedia