This travel note involves the following attractions: Karez - Flame Mountain
Our itinerary is as follows:
Day 1 Depart for Lanzhou-
Day 2 Lanzhou - Jinyintan - Qinghai Lake
Day 3 Qinghai Lake - Chaka Salt Lake - Qilian
Day 4 Qilian - Zhangye - Jiayuguan
Day 5 Jiayuguan - Mogao Grottoes - Dunhuang
Day 6 Dunhuang - Mingsha Mountain - Crescent Lake - Urumqi
Day 7 Urumqi - Turpan - Urumqi
Day 8 Urumqi - Tianshan Tianchi - Fuyun County
Day 9 Fuyun County - Keketuohai - Burqin
Day 10 Burqin-Kanas-Jiadengyu
Day 11 Jiadengyu - Baisha Lake - Burqin
Day 12 Burqin - Devil City - Jinghe County
Day 13 Jinghe County - Nalati
Day 14 Nalati - Bayinbulak
Day 15 Bayinbulak - Rob Village - Korla
Day 16 Korla Tianshan Mysterious Grand Canyon - Kizil Thousand Buddha Caves - Urumqi
Day 17 Return
Day 7: Karez @ Turpan
Karez, which means "well hole", is a special irrigation system in desert areas, common in Turpan, Xinjiang, China. It was recorded as early as in "Historical Records", and it was called "Jingqu" at that time, and it was called "Kanerzi" in Xinjiang Uighur. "Hanshu Biography of the Western Regions" records: "The Han Dynasty sent Xin Wuxian, the general of the Qiang Dynasty, to Dunhuang with 15,000 soldiers, and sent envoys to the west of Beidanhoujing according to the schedule, in order to pass through the canal and turn to the valley." A lot of construction has also been done.
The people in Xinjiang are simple, industrious and good at creating miracles. Karez, together with the Great Wall and the Beijing-Hangzhou Grand Canal, are known as the three major projects in ancient China, but their popularity is far less than that of the Great Wall, the Beijing-Hangzhou Grand Canal, and even Dujiangyan.
On the vast land of Xinjiang, countless snow-capped mountains have stood here for thousands of years. The warm sun shines on the mountain peaks, and the snow water gradually melts, forming thousands of trickles along the mountains, rivers and ravines.
Turpan is one of the extremely arid regions in China, with an annual precipitation of only 1.6 centimeters and an evaporation of more than 3 meters, making it a veritable drought pole. Such climatic conditions are extremely unfavorable to agriculture. However, there are Bogda Mountains in the north of the Turpan Basin, Karawucheng Mountains in the west, and low terrain in the south. The soil in Xinjiang is mostly gravel and has strong water permeability. In summer, a large amount of snowmelt and rainwater flow into the basin. , most of them will seep into the Gobi and merge into an undercurrent, which provides a rich source of groundwater for the Karez well.
For more than 2,000 years, Karez has bred generations of Turpan people in this way.
Three-dimensional structure diagram of Karez well
Do you understand the principle in the picture? Find the water source at the undercurrent of snow water in the mountains, and drill vertical wells of different depths at certain intervals. The water outlet of the underground channel is connected with the surface channel, and the groundwater is led to the ground to irrigate the mulberry fields. Shafts were used for excavation and ventilation, and culverts were used for underground canals. It is somewhat similar to the self-flowing well in Australia.
The Greatness of Karez
There are more than 1,700 Karez wells in Xinjiang, most of which are located in Turpan and the Hami Basin. This is a huge legacy left by the ancestors and a handed down achievement of the working people of all ethnic groups in Xinjiang. Moreover, although the name of Karez is a well, it is actually an underground culvert, and the amount of work is not as simple as drilling a well downward. It is not as easy as digging a canal on the ground.
Karez is composed of four parts: 1. Shaft, 2. Underground channel, 3. Longkou, and 4. Open channel (waterlogged dam).
1. Shaft: connected to the deep ground, it is a channel for transporting underground sand or silt when excavating or cleaning the Karez culvert, and it is also an air supply vent. The depth of the well varies depending on the terrain and the level of the groundwater level. Generally, the closer the shaft is to the source, the deeper the shaft is. The deepest shaft can reach more than 90 meters. The distance between shafts varies with the length of Karez, and generally there is a shaft every 20-70 meters. A Karez well has as few as 10 shafts and as many as hundreds of shafts. The wellhead is generally rectangular or circular, 1 meter long and 0.7 meters wide. When approaching Turpan by car, on the Gobi Desert outside the lush oasis, you can see piles of round earth bags descending the high slope, shaped like small volcanic cones, and stretching out to the oasis in an orderly manner. , is the shaft mouth of Karez.
2. Underground channel: Also known as underground channel, it is the main body of Karez. His function is to gather the water in the underground aquifer to it, generally digging from low to high according to a certain slope, so that water can flow out of the surface automatically. The culvert is generally 1.7 meters high and 1.2 meters wide, the short one is 100-200 meters, and the longest one is 25 kilometers long.
The culverts are all excavated underground. There were no modern tools such as compass (Karez began in the Western Han Dynasty, and the compass was introduced from the Central Plains to the Western Regions in the Ming Dynasty), positioning system, etc. when excavating the culvert. To determine the direction, the ancestors of Turpan created the stick orientation method. That is, in the middle of two adjacent shafts, a well rope is hung above the well head, and a sharpened horizontal wooden stick is tied to the well rope. The direction where the two stick tips face each other is the shortest distance between the two shafts. straight line. Then use the same method to orientate the wooden sticks under the shaft, and the underground people can dig in the direction pointed by the wooden sticks.
When digging the culvert, the people of Turpan also invented the oil lamp orientation method. The orientation of the oil lamp is based on the principle that two points form a line. Two oil lamps with mouths on the side are used to determine the location of the culvert excavation, and it can ensure that the top of the culvert is parallel to the bottom. However, the oil lamp positioning can only be used on the same operating point, how can different operating points be consistent? When digging a culvert, hang an oil lamp on the center line of the shaft. The digger faces the oil lamp and digs his own shadow all the time so as not to deviate from the direction.
The deeper the culvert, the narrower the space, only allowing one person to bend down and dig forward. Since the soil in Turpan is hard calcareous clay and the working surface is very narrow, it is difficult to dig out a 25-kilometer-long culvert. It is said that the melted snow in the Tianshan Mountains is icy cold, and workers digging underground canals have to kneel in icy water to dig soil. Therefore, workers who have been engaged in underground canal digging for a long time generally do not live longer than 30 years old. Generally speaking, it takes 60 years to dig a shaft, that is, the time of two generations. From a bird's eye view, there are so many wellheads, how many generations of hard work and wisdom have been spent on this. Therefore, the 5,000-kilometer Karez Well in Turpan is called the "Underground Great Wall", which is really well-deserved.
There are also many advantages of the culvert. Due to the high temperature and dryness in Turpan, the evaporation is large, the water in the culvert is not easy to evaporate, and the water flowing underground is not easy to be polluted. Moreover, the water flowing out of the culvert is naturally filtered through thousands of layers of sand and stones, and finally The natural mineral water is rich in many minerals and trace elements. The local residents have been drinking it for hundreds of years, and many people live to be over 100 years old. Therefore, Turpan is known as the hometown of longevity in China.
3. Longkou: It is the junction of the Karez open channel, the underground channel and the shaft mouth, and it is also the first outlet for the snow water from the Tianshan Mountains to penetrate through the stratum and flow to the open channel through the underground channel.
4. Open channel waterlogging dam: After the underground channel flows out of the ground, it becomes an open channel. Nullahs, as the name suggests, are ditches that run up the surface of the earth. People have built water storage ponds with the functions of water storage and water regulation at certain locations. Such large and small water storage ponds are called flood dams. The water is stored in the dam, where it is needed, it will be sent there.
More than 1,700 Karez wells have been dug, and the total length can reach 5,000 kilometers, 5,000 kilometers, not including the thousands of shafts.
If you have no concept of 5,000 kilometers, first look at the 1,700-kilometer length of the Beijing-Hangzhou Grand Canal, and then look at the concept of 5,000 kilometers in Karez:
Hu Huanyong line, less than 5,000 kilometers
If the amount of shaft construction is also taken into account, it is conservatively estimated that the excavation volume of the Karez well will be excavated at a distance of 3x4x1=12 cubic meters, then more than 60 million cubic meters of earth and rock will be excavated for a length of 5,000 kilometers, which is equivalent to a straight line with an area as large as Tiananmen Square. Digging a 137-meter-high pit, I estimate that a giant meteorite can almost open such a huge deep pit, and the amount of soil and rocks can be piled up to form a 25cm thick and 2m high wall that can circle the earth's equator three times. Moreover, Karez also involves underground operations, vertical excavation, and overcoming surging groundwater, all of which are completed without the help of machines.
The Kaner Well began 2,000 years ago, has been dug for more than 5,000 kilometers, and has been used for more than a thousand years. It is not an exaggeration to call the three major ancient Chinese projects.
Karez, which flows silently, is little known
First, we can’t see the Karez underground at all, and many of the exposed shafts are in no-man’s land (Xinjiang is too big and many places are undeveloped), unlike the Great Wall or the Grand Canal, it’s very interesting to just stand there With a high sense of existence, she just nurtures the people of Xinjiang secretly, but is not directly admired by people.
Second, she is located in the Western Regions, far away from the Central Plains. Until now, the origin of Karez technology has not been determined. According to the latest information, Karez technology is likely to be introduced from the Middle East, not original in China, and it is not so confident to write it into textbooks (but it is worth pointing out that Xinjiang Karez was established in Lin Zexu and Zuo Zongtang A large number of constructions have been carried out under the promotion of the Western Regions, and the ancestors of the Western Regions belonged to the Chinese civilization circle for a long time in history. The existing Karez was jointly completed by the laborers of the Han and the ancestors of the Western Regions, so I think it can be said that the Karez in Xinjiang belongs to the Chinese civilization. Civilized).
The other is that the Xinjiang area was far away from the Chinese civilization circle after the Han Dynasty, and the main civilization changed hands several times. This resulted in very few records in history books, and even fewer poems and documents about Karez than the Great Wall and canals. Coupled with the vast distribution area and remote location, it is difficult to research and promote.
Third, it is not linked to historical events. First of all, the construction of Karez is not a large-scale government action like the Great Wall and the Grand Canal, and there are quite few stories in history. The Great Wall was built by Qin Shihuang and perfected throughout the dynasties. Emperor Sui Yang built the Grand Canal and even led to the subjugation of the country. One protects China for a thousand years, and the other prospers China for a thousand years.
But who started to lead Karez, and what major historical events accompanied it, it is not as famous as other projects at all, which leads to the fact that the historical popularity is not high enough, so that it is not taken seriously in history books.
In this way, the great feat that is located in a remote place, not well-known in history, and quietly hidden underground is almost forgotten.
Karez recent situation
In recent years, with the deterioration of the ecological environment in Xinjiang, especially in Turpan, the oases have been seriously damaged, and the groundwater resources in Xinjiang have been continuously reduced. Many Karez wells have dried up. Currently, only more than 700 are still flowing normally. On the other hand, with the construction of dams on some rivers in the upper reaches, the water resources in the lower reaches are reduced, and the maintenance of Karez wells is more difficult, so the utilization rate is also reduced as before.
At the same time, due to the process of modernization, the water consumption is constantly increasing. For example, factories and oil fields are pumping a large amount of groundwater, which leads to the continuous drying up of Karez wells. The construction of motorized wells and reservoirs has replaced some Karez wells.
The other ones are quietly hidden under the earth, silently waiting for the fate of drying up. It will not attract people's attention, and only a small number of people will sigh with regret:
Oh, that is the mother well that once made Xinjiang people prosperous.
