With great effort, the eldest grandson Yuanhong and his party got rid of the wolves, and many people were blistered on their chests and backs, and they were wiping the ice with ice, and a drop of wailing was all over the field.

The handsome face of the eldest grandson Yuanhong was also blackened, Angel carefully wiped it, but she didn't know that she wanted to laugh more and more, she had never seen the eldest grandson Yuanhong look like a wolf.

"What are you laughing at?" The eldest grandson Yuanhong enjoyed Angel's service, and while being confused by Angel'er's attitude, he looked at Angel suspiciously.

Shaking his head, "No, nothing, I just heard that it's almost desert, and I'm just a little excited." ”

"Excited? What's there to be excited about, just a barren land! "Changsun Yuanhong is in a bad position, he lives in the south, the way of survival in the north makes him very uncomfortable, there is no grass in the desert, and the people who survive there are poisonous snakes and beasts, and Changsun Yuanhong hates the desert even more.

Desert refers to sandy desertified land. One-third of the Earth's land mass is desert. Because there is very little water, most people think that the desert is desolate and lifeless, and it is called "barren sand". Compared to other areas, there is not much life in the desert, but if you look closely, you will find that there are many animals hidden in the desert, especially those that only come out at night.

The desert area is mostly sandy beaches or sand dunes, and rocks under the sand are often found. The soil is thin and there are few plants. Some deserts are salt flats, completely devoid of vegetation, and deserts are generally wind-formed landforms.

There are sometimes valuable mineral deposits in the desert, and many oil deposits have been discovered in recent times. Because the desert is rarely inhabited, it is relatively easy to exploit resources. The desert has a dry climate, but it is a popular destination for archaeologists as many human artifacts and earlier fossils can be found there.

On the other side of the desert, there may be more countries, and the eldest grandson Yuanhong and his party may be more dangerous, and they don't know which kind of desert they are on the other side, and what they usually see is the green desert, the hot desert and the cold desert.

A "green desert" is a large area of green forest in which trees of a single species, of the same age and height, and are very dense. The dense single canopy completely blocks the sunlight and prevents the growth of the underlying vegetation, and the understory lacks intermediate and undercover vegetation.

The reason why it is called "desert" is that the plant species in such a forest are extremely single, and cannot provide food or suitable habitat for a variety of animals, so the animal species are also very rare; The second is that the surface vegetation of such forests is very poor, so the ability to retain water is very poor, and it is generally dry and prone to fires; The third is that the level of biodiversity of such forests is extremely low, so the ecology is very fragile, and there is a lack of control of pests by natural enemies, which is very susceptible to insect pests, and once insect pests occur, it is easy to cause large-scale damage.

Thermal desert is a desert located in the tropics, mainly due to strong solar radiation, violent evaporation, and long-term dry monsoon control of the desert. In contrast to this, the cold desert is named because it is located in a colder zone, and the formation of the cold desert is mainly due to the fact that the precipitation in the area controlled by the continental climate is very small, and it is controlled by the dry and cold monsoon for a long time.

The cold desert ground is full of large and small stones, which is due to the drastic change in the temperature of the desert, and after strong weathering, the rocks change from large to small and become fragments.

Most of the reasons for the formation of deserts are desertification, that is, after the destruction of vegetation, the ground loses its cover, and under the action of arid climate and strong winds, the green fields gradually become desert-like landscapes.

Land desertification occurs mainly in arid and semi-arid areas, and the key factor in the formation of deserts is climate, but in the edge of the desert, native vegetation may be grasslands, which have been desertified due to anthropogenic reasons.

Desert areas have a dry climate with little rainfall, with annual precipitation of less than 250 mm, and some desert areas have less than 10 mm of annual precipitation, but there are occasional sudden heavy rains. Evaporation in desert areas is significant, far exceeding the local precipitation; The humidity of the air is on the low side, and the relative humidity can be as low as 5%.

Desert temperatures vary greatly, with average annual temperature differences generally exceeding 30 degrees Celsius. The difference in absolute temperature is more often above 50 degrees; The daily temperature difference is extremely significant, with near-surface temperatures reaching 60 to 80 degrees Celsius at noon in summer and autumn, and dropping below 10 degrees Celsius at night. Desert areas often have clear skies, cloudless skies, and strong winds, with maximum winds reaching hurricane strokes.

Causes of tropical deserts: Mainly shrouded by the subtropical high pressure, the air sinks and warms more, inhibits surface convection, and is difficult to cause rain.

In the desert, there are all kinds of phenomena, which are no less deceptive than the danger caused by the lack of water.

In the desert, because the sand and gravel are scorched by the sun during the day, the air close to the sand layer rises very quickly, forming a temperature distribution of hot in the lower layer and cold in the upper layer, resulting in the phenomenon that the density of the lower air is much smaller than that of the upper layer.

At this time, the light of the scene in front of you will be refracted from the dense air to the less dense air, thus forming a mirage. From afar, it looks like a reflection in the water. People who have traveled long distances in the desert, hot and thirsty, often mistakenly think that they have reached the shore of a cool lake when they see a mirage, but when a gust of wind and sand sweeps through, it is still an endless desert, and this scene is just a mirage.

It is a large stone that has been broken again and again after hundreds of years of thermal expansion and contraction and natural weathering, forming a circular circle of gravel on the ground, which is very similar to artificially arranged works, which are actually naturally formed.

The wind erosion column is mainly developed in the bedrock area with vertical joints, and after long-term wind erosion, it forms isolated columnar rocks, so it is called wind erosion column. It can stand alone or in groups. Abrasion is strong due to the high amount of sand in the air flow near the surface. If coupled with the difference in the lithology of the bedrock, the wind erosion column is often eroded into a rock with a large top and a small base, which resembles a mushroom, which is called a wind erosion mushroom. The main cause of its formation is the erosion of wind. It will collapse when it is severely eroded by wind.

Wind erosion mushrooms are generally an epiphytic form of wind erosion castles and other landforms developed in bedrock areas. It refers to the surface shape formed by wind erosion and abrasion of surface materials, mainly formed by wind erosion and rain erosion, and the surface is exposed to wind and sun for tens of millions of years, so that the flat sandstone layer on the surface forms various landform forms such as wind erosion wall feats, wind erosion mushrooms, wind erosion columns, wind erosion ridges and wind erosion depressions, residual mounds, castles, etc., and the Yadan landform is named after the most typical wind erosion landform in the Yadan area near Lop Nur.