Write a eulogy for Dayanhe

Dujiangyan is groundbreaking in the history of water conservancy in the world, and Qingcheng Mountain is groundbreaking in the history of Taoism in China. Dujiangyan was founded around 256 BC and has a long history of more than 2250 years. More than 2,000 years ago, Li Bing, the governor of Shuqin County, learned from the previous experience in water control, skillfully used the special terrain at the entrance of Minjiang River according to the local geographical characteristics, chose a suitable position as a weir, used the height difference, complied with the laws of nature, and adopted the principle of expanding with heat and contracting with cold when the production tools and construction technology were relatively backward, thus chipping away the pile, splitting Leiyu Mountain and crossing the "second river" (Danjiang and Jianjiang are now along the river. Dujiangyan has a long history and great benefits, which has created a precedent for water conservancy projects in China and even the world. Qingcheng Mountain is a sacred place founded by Taoism in China. It has been innovated according to the unique cultural form of the Chinese nation, and gradually developed into the state religion of China, with outstanding cultural value and unprecedented pioneering. Dujiangyan is the crystallization of human civilization, which is unique in the history of science and technology in the world. Li Bing presided over the creation of Dujiangyan. Correctly handle the relationship between the main projects such as Yu Zui water diversion levee, Sha Fei weir spillway and Baojiangkou water intake, make them interdependent, complementary in function, skillfully coordinated and integrated, form a systematic project with reasonable layout, and jointly play the important roles of diversion and sediment separation, flood discharge and sediment discharge, water diversion and dredging, so as to ensure that there is no shortage of dry water and no overflow. Specifically, the fish mouth diversion dike is used to divert water from Mianjiang River for irrigation. In dry season, 60% of the water in Mianjiang River is automatically introduced into Neijiang and 40% is discharged into Waijiang River. In the event of a flood, 60% of the water is automatically discharged into the Waijiang River and 40% is introduced into Neijiang River. Dujiangyan was built at the corner of Mianjiang River, which reached Dujiangyan. The surface water with less sediment concentration flows to the concave bank, and the bottom water with more sediment concentration flows to the convex bank, which discharges most of the sediment washed down from the outer river by the flood. A small amount of sand and gravel entering Neijiang, with the support of Hutouyan extending to the center of the river, the restraint of Baojoukou and the jacking of "retaining piles", will discharge most of the sand and gravel from Feishayan and herringbone dike into the outer river to prevent the water intake of Baojoukou and the main stream of the irrigation area from silting; Using the water intake of bottle mouth to control the inflow not only ensures the irrigation water, but also avoids the flood from flooding into Neijiang irrigation area and causing disasters. Dujiangyan can automatically adjust the amount of water entering the irrigation area, making the Chengdu Plain "flood and drought follow people" and become a granary of Tianfu. Dujiangyan is a model of automatic water diversion, flood discharge and sediment discharge by successfully using the fluid gravity formed by natural bends. When building the weir, Li Bing also buried a stone horse in the river as a sign of scouring the beach, and set up a "Three Stone Man" to observe the fluctuation of water regime, which pioneered the ancient water regime measurement in China. All previous dynasties attached great importance to Dujiangyan water conservancy project, gradually improved the management organization, established the annual maintenance and flood control maintenance system, and accumulated and summarized valuable water control experience such as "six-character formula", "three-character classics" and "eight-character motto", which made the ancient weir develop continuously. More than 2,000 years ago, Dujiangyan made such a great scientific achievement, which is unique in the world and is still the highest water conservancy project in the world. 1.872, German geographer Richthofen (Richthofen 1.833- 1.905) praised "the perfection of Dujiangyan irrigation method is unparalleled in the world". During the period of 1 986, Franjem, Secretary General of the International Irrigation and Drainage Committee, and experts from various countries of the International River Sediment Society visited Dujiangyan and spoke highly of Dujiangyan's scientific irrigation and sediment discharge functions. 11In March, 1999, UN-HABITAT officials visited Dujiangyan and suggested that Dujiangyan Water Conservancy Project participate in the 2000 UN "Best Water Resources Utilization and Treatment Award". Qingchengshan Taoism and Dujiangyan water conservancy project are epoch-making masterpieces of Chinese culture, which have had a great influence on later generations. Since China Taoism was founded in Qingcheng Mountain, the blood of Taoism has been constantly multiplying, gradually expanding from the mountain to the outside, and even to the whole country. Since then, the heavenly masters of Longhu Mountain have come to Qingcheng Mountain to worship their ancestors. During the Jin Dynasty, Qingcheng Mountain was the center of Bashu Taoism. Du Guangting, a Taoist priest in Qingcheng Mountain, annotates and disseminates Laozi's theory, and studies and sorts out Taoist theory, which is called "supporting education, one person under the world" by Taoist circles. 1995, the National Quanzhen Educational Administration School was held in Qingcheng Mountain. Therefore. Taoism in Qingcheng Mountain has an immeasurable influence on Taoism in China. The establishment of Dujiangyan Water Conservancy Project is the great creation of the excellent wisdom of the Chinese nation and the crystallization of scientific management and maintenance. Li Bing draws lessons from the experience of ancient Shu people in water control, uses local materials and adopts unique engineering techniques such as "bamboo cage", "drifting", "dry pebble" and "sheepfold" to carry out flood control and annual maintenance, which is economical and effective. Dujiangyan is an original river engineering technology, which is widely used in flood control and emergency rescue in the Yellow River Basin and the Pearl River Basin. Since the Han Dynasty, it has played an irreplaceable role in controlling sudden floods, and this scientific principle is still widely used as an advanced method for flood fighting and emergency rescue. Dujiangyan is an epoch-making masterpiece of water conservancy engineering technology in China. Qingcheng Mountain is the birthplace of Taoism in China. In A.D. 143 (the second year of Han 'an), there were ancestral mountains and ancestral halls of Taoism in Shi Tian. Zhang Ling, the founder of Taoism, came to Chicheng Cliff House in Qingcheng Mountain and founded "Five Mi Dou Daoism" based on the knowledge of Huang Lao in the pre-Qin period, that is, Shi Tian Daoism. Zhang Ling emerged in the mountains, and Qingcheng Mountain took the ancestral mountain and ancestral court of Shi Tian Daoism as the birthplace of Taoism. During the Han and Jin Dynasties, Taoism gradually flourished, and Fan Changsheng moved to Qingcheng Mountain to help establish the Han regime.