(A) the development of water conservancy in the middle and lower reaches of the Yangtze River during the Sun Wu period
South China has a warm climate, abundant rainfall, ponds and fertile land, which is very suitable for farming, especially for rice planting. However, if there are no corresponding water conservancy facilities, the superior water and soil resources will not be rationally utilized and agricultural production will still not be guaranteed. Since the Eastern Han Dynasty, agriculture and water conservancy in the south of the Yangtze River have developed, but they are only concentrated in some points. As far as the vast areas are concerned, the degree of development is not high, and it is still in a state of vast territory and sparsely populated. The overall level of agricultural economic development obviously lags behind the Yellow River Basin in the north. Sun Wu is based in the east of the Yangtze River, and the middle and lower reaches of the Yangtze River are its political and economic centers. In order to maintain the huge military expenditure, we must vigorously develop agriculture and water conservancy and establish a relatively solid economic foundation, so as to compete with Cao Wei in the north and Shu Han in the west. To this end, Sun Wu, like Cao Wei, also vigorously cultivated land, developed water conservancy, developed agricultural production, ensured the supply of rations, and increased fiscal revenue in his ruling area. Sun Wu's reclamation began in the eighth and ninth years of Jian 'an (203-204) and lasted for more than 70 years until the Western Jin Dynasty wiped out Wu. Centralized leadership and unified management are more conducive to large-scale water conservancy construction and land development. During the reign of Sun Wu, a major feature of farmland water conservancy was the simultaneous development of land and water conservancy, and large-scale reclamation meant large-scale water conservancy construction. Therefore, with the implementation of Sun Wutun system, the water conservancy construction in the middle and lower reaches of the Yangtze River has developed at an unprecedented speed. The area and form of Sun Wu's reclamation have been expounded in his works, so I won't repeat them here. This paper only introduces the development of its water conservancy cause around the above characteristics.
1. The development of farmland water conservancy in Taihu Lake area is the most developed area in the south of the Yangtze River. During the Qin and Han dynasties, many water conservancy projects such as seawalls, polder fields, weitang and canals were built here. At the end of the Eastern Han Dynasty, this area was already a scene of "fertile Wan Li, rich gentry". Sun Wu, based in Jiangdong, continued to devote himself to water conservancy and farmland cultivation in order to make Taihu Lake an economic center. In Jian 'an in 1989, Sun Quan appointed Lu Xun as the reclamation captain of Haichang (now Haining, Zhejiang) to manage the water reclamation in the eastern and southern plains of Taihu Lake. Later, in Piling (now Changzhou, Jiangsu), a captain of Diannong was set up. The business scope of a captain of Piling Diannong is quite wide, covering Wuxi, Jiangyin, Changzhou, Danyang and Dantu. In order to speed up the development of farmland water conservancy in Taihu Lake area, Sun Wu government sometimes organizes people from all walks of life to carry out a general war to reclaim farmland. For example, during the Chiwu period, "each county went out of the department, and Chen Biao, the captain of Xindu, and Gu Cheng, each led ten thousand people, and they would rent piling, with tens of thousands of men and women." Tens of thousands of people will rent piling, which shows the scale of wasteland reclamation.
The process of expanding reclamation in Taihu Lake area is actually the construction process of farmland water conservancy. During the period of Sun Wu, the water conservancy in Taihu Lake area was roughly as follows:
(1) Construction of dykes and ponds in Taihu Lake. The dike along the southeast coast of Taihu Lake separates Taihu Lake from water towns such as Hudong and Hunan, which is an important prerequisite for the development of agricultural production in the southeast of Taihu Lake. Building dikes and ponds along the lake began as early as the Spring and Autumn Period. According to legend, Li Tang, located 35 miles east of Changxing County, was built by Fan Li in the late Spring and Autumn Period. Later, in the second year of the Western Han Dynasty (AD 2), Gao built a high pond 25 miles northeast of Changxing County to "block the water of Taihu Lake". During the period of Sun Wu, with the development of reclamation in Hudong area,
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(1) the reflection volume may 4th Wu Shu Lu Su biography.
(2) the reflection volume 52 biography of Wu Shu and Zhu Gejin Pei Songzhi note cited "Wu Shu.
(3) Qing Jin Youli: "Preparation for Taihu Lake" volume three quotes "Xing Wu Mountain Market Name".
(4) Qi: "Wujiang Water Test" Volume 1.
The dikes and ponds on the east and south banks of Taihu Lake are frequently constructed. In order to prevent the flooding of Taihu Lake, Sun Xiuwei started from northern Xing Wu in the east and Changxing in the west, which was called "Qingtang". The purpose was to "escape from the water, defend the embankment and fertile land, and lead a trip to the future". The completion of Qingtang has largely controlled the overflow of lake water, improved the water and soil environment in Hudong and Hunan, and promoted the agricultural development in Hudong and Hunan.
(2) Building seawalls. The southeast of Taihu Lake area is close to the sea. The altitude of coastal land is far from being able to stop the attack of high tide. Therefore, coastal people build seawalls to defend against tides, improve coastal brine avoidance areas and ensure normal agricultural production. According to Wu Yue Shi, Sun said, "There is a salty seawall in Jinshan at the southeast end of Huating Valley". In addition, "Begonia in Jiaxing Prefecture" quoted Zhao Tu Ji as saying: "Begonia is a hundred miles away from the county and stretches for 170 miles, spanning Haiyan and Pinghu counties." Jinshan was connected with the land during the Han and Wei Dynasties, and fell into the sea and separated from the mainland after the Tang Dynasty. Before and after Sun Wu, there was no record of Jinshan building seawalls. Therefore, the Jinshan salt seawall was probably built by Sun Wushi. At that time, Sun Wu was reclaiming wasteland in Haichang, and it was very possible to build seawalls along the southeast coast to meet the needs of agricultural reclamation development.
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(1) dry dragon "Huzhou Zhi Xin house clear pond embankment".
(2) See History of Farmland Water Conservancy in China edited by Wang Jialun and Zhang Fang, Agricultural Press, 1990, 158 ~ 159.
(3) Excavation of plain river. In Taihu Lake area, the river network is dense. However, if these water surfaces are not restrained and guided, they will often cross the water everywhere and touch the ground into rivers, endangering agricultural production. In the long-term production practice, many tanghe ditches have been artificially dug to limit and guide the water flow. These Tanghe ditches have many functions such as flood control, drainage, irrigation, drinking and transportation. , densely distributed in Taihu Lake area, is the product of water and soil resources development and utilization in Taihu Lake area for thousands of years. Among them, many such projects started in the period of Sun Wu, but unfortunately, due to the lack of records, only one example of Changguangxi was seen. Guangxu's "Wuxi Jingui County Records" contains: In the eighth year of Chiwu (245), Wei Chenxun, a school, dredged Changguangxi. According to "Health Records" (Volume II), about eight years ago, Chen Xun presided over the stationing of troops in Taihu Lake, with tens of thousands of troops stationed. Changguangxi may be a Tanghe diverted to meet the needs of reclamation. The northern mouth of Changguangxi is connected with the northern branch of Taihu Lake, and the southern mouth is connected with Taihu Lake. It is thirty miles long and more than one mile wide, and runs through the soil stocks in the southwest of Wuxi. Judging from the place where it passes and the connection between both ends and Taihu Lake, it seems to be a project to divert Taihu Lake to irrigate farmland.
(4) Renovation and excavation of canals. The section from Danyang to Dantu, the northern section of Jiangnan River, has always been the focus of dredging because of its high terrain and continuous mountains on both sides. During the period of Sun Wu, Cenhun first dredged this section of the river, "chiseling Dantu to Yunyang, but Duye (now east of Zhenjiang 15) and Xiao Xin (now north of Danyang 10) all cut ridges, which is difficult". This project is very arduous. After this treatment, the shipping conditions have been improved. Wang Mingsheng, a Qing man, said: "Since ancient times, Wuxian has set off from Sun Shi and passed through Wuxi, Wujin, Danyang and Dantu waterways." Pet-name ruby Cen Can's management of the northern section of the south of the Yangtze River not only facilitates shipping, but also provides good irrigation conditions for agricultural production.
2. Reclamation of Danyang ancient lake area. The ancient Danyang Lake is located in five counties of Lishui, Gaochun, Dangtu, Wuhu, Nanling and Xuancheng in Jiangsu, and its water surface is quite wide. Land reclamation around the lake has a long history, and the farmland around the lake is flat and fertile, and irrigation is convenient, which is very attractive to the government and farmers. Guangxu's "Gaochun County Records Mountains and Rivers" contains: "Xiangguowei has a field of 48,000 mu and a week of 40 miles. In the Spring and Autumn Period, the main city of Wu was the city of all races, and because the building was attached to the city, it was fertile ground for Wu. " It can be seen that reclamation around the lake began in the Spring and Autumn Period. After Sun Wu established the capital, the ancient Danyang Lake area was also one of the important reclamation areas. Located in the lake (in present-day dangtu county), it supervised agriculture, reclaimed farmland on a large scale, developed marshes along the lake, cut off water from the lake, broke ground to cultivate land, and developed agricultural production. Jinbaowei, 60 miles north of Xuancheng today, is part of the ancient Danyang Lake. "Sun Shi started in Jiangdong, and those who avoid chaos in the Central Plains return to it, and there is no place to plant. Only then will money and other places be established around the field, and all boundaries are mostly in the city. " Another example is Pulitang, in the autumn of the third year of Yongan (260), "A surname built Danyang Hutian and Lipu.
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① See Wu Tongju: Jiangsu Water Conservancy Encyclopedia, Volume 11.
(2) The Taiping Magnolia Volume 170 The Records of Counties and Counties was quoted from Lu Wu.
(3) The 17th History Discussion, Volume 42.
(4) the republic of China "Gaochun county annals" volume 15.
Litang 1. Probably because of the improper location, it didn't succeed this time. Eight years later, Xixi once again proposed to surround Lake Puli and "build Puli field and restore the old site". It can be seen that the activities of reclaiming ancient Danyang Lake account for a large part of agricultural production in this area. In addition, the famous Yongfengwei in Gaochun and Baowei in Wuhu County were all built during the period of Sun Wu.
Sun Wu promoted reclamation in Gudanyang Lake area, which promoted the development of polder water conservancy in this area. Through the hard work of immigrants and soldiers, countless fertile fields have been cultivated in the foggy Gudanyang Lake area, providing superior water and soil resources for the development of rice farming here. This not only became a rich agricultural economic zone of the Sun Wu regime at that time, but also laid the foundation for the continued development of the Six Dynasties and later generations.
3. Farming and Water Conservancy in Riverside Areas There are more than 10 villages set up by Sun Wu regime in the riverside areas in the middle and lower reaches of the Yangtze River, which can be roughly divided into two areas: Jiangbei villages with 10,000 people as the center and North and South villages with Wuchang as the center.
(1) Jiangbeitun District. Wankou, located in the southwest of Anqing City, Anhui Province, is the estuary of Anhui Province. There is an alluvial plain in the lower reaches of Anhui Province with fertile land. Cao Cao once sent Lu Jiang as the satrap, "Tunwan, wide open rice fields" (3), to prepare for the southern conquest of Wu. At that time, Monroe suggested to Sun Quan: "Wan Tian is rich and beautiful. If it is mature, the number will increase. If you are several years old, you should get rid of it early. " (4) So, in the 19th year of Jian 'an (2 14), Sun Wu conquered Anhui in May, captured tens of thousands of Cao Cao men and women, and continued to farm in Daxing, Anhui. Farmland reclamation in Jiangbei mainly grows rice and needs corresponding water conservancy facilities. Therefore, with the continuous expansion of reclamation areas, farmland water conservancy has also developed accordingly. During the Jian 'an period, Lv Meng was appointed as the satrap of Lujiang River, and cut stones to pass water in Wancheng, "filling more than 100 hectares of water fields", further expanding the original Wutangpi irrigation area, making it "utilitarian and humanized" and the people set up temples to worship it. Due to the construction of irrigation works, Wancheng area reclaimed a large area of paddy fields and became an important rice producing area at that time. Just a village in the west of the wasteland north of the Yangtze River can be "welcomed by tens of thousands of people".
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(1) the reflection volume on June 4th, Wu Zhi spread Yang Hangchuan.
(2) the reflection volume 61 biography of wu kai.
(3) (4) The Three Kingdoms Volume May 4th Biography of Wu Mengchuan.
(5) The reflection, May 4th volume, Lv Meng biography, peaceful universe, volume 125.
⑥ Reading Notes on the Stone in Volume 26 of Wangjiang County Records.
(2) villages in the north and south. The development of north and south villages centered on Wuchang in the middle reaches of the Yangtze River has promoted the development of farmland water conservancy in some areas of the middle reaches of the Yangtze River, mainly in the following places:
First, Yangxin irrigation area. On the south bank of the Yangtze River, Sun Wushi once built Yangxin Irrigation District. "Notes on Shuijing Jiangshui" contains: Jiangshui "goes further east, crosses the north of Charlotte County (now Yangxin East, Hubei Province), and the right bank is rich in water. Water flows from Qingxin Mountain in Yangxin County, flows westward and passes through Yangxin County. ..... around the water, public and private irrigation, salty into fertile soil, where is the old village? " Rich water is a small tributary of the south bank of the Yangtze River, and the valley plain is suitable for farming. During the reign of Sun Wu, Xiajun and Yangxin tunnels were built along the water-rich coast to divert water for irrigation. Judging from "public and private irrigation, salt becomes fertile soil", farmland water conservancy in Yangxin area was quite developed at that time.
The second is the irrigation area that draws water from Pakistan. The irrigation area that draws water from Pakistan is on the north bank of the Yangtze River, near the ancient Wuchang. On the left side of the river, the water is injected by the dam, and the water flows out from the Dabie Mountain Lingshan below Honglou County. ..... Wu Shi, the old camp stood by the water, pumping water to water the wild. "The South-to-North Water Diversion Irrigation District is located in Luotian, Hubei Province, at the junction of Wu and Wei, and cultivated land is of great significance. So water conservancy irrigation has also been carried out.
Third, Laishuitun District. From the 14th to 18th year of Jian 'an, Zhou Tai "sent troops to cultivate fields and cultivate fields", built water conservancy projects, cultivated fields and reclaimed land, and irrigated farmland with cen water. Cen, in the lower reaches of Lishui River in Hunan, Laishui is a tributary of the north bank of Lishui River. Volume 37 of Notes on Water Classics says: Lishui River passes through Tangxian County in the east (governing Anxiang County in Hunan Province in the north), and "enters the county, enters the water in the left, leaves the Tianmen County boundary in the northwest, and reaches Peipingtun in the south, which is used for scouring water to irrigate thousands of hectares of fields." The "Jingping Village" referred to by Zhu may be the situation after the construction of water conservancy and land reclamation in Zhou Tai. Thousands of water conservancy projects have been introduced, which shows the large scale.
In addition, the irrigation and water conservancy undertakings in Jiangling and Anlutun areas have also developed to some extent. The History of the Three Kingdoms, Volume 27, Biography of Shu Wei and JI Wang records: "There are two rivers in Jiangling, Ju and Zhang, and thousands of hectares of fertile land. Around Anlu, Dianchi Lake Woyan. " It reflects that the water conservancy in these wasteland areas also has a considerable scale.
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(1) the reflection, Wu Taichuan volume one.
(2) See History of Farmland Water Conservancy in China edited by Wang Jialun and Zhang Fang, Agricultural Press, 1990, 166 ~ 167.
Sun Wu's regime persistently carried out the reclamation system, vigorously developed and utilized the water and soil resources in the middle and lower reaches of the Yangtze River, and developed water conservancy, which not only laid a solid economic foundation for Sun Wu at that time, but also made pioneering efforts in developing water networks in the south of the Yangtze River, reclaiming lake fields, and building water conservancy in polder fields, laying a foundation for the rapid development of water conservancy and agricultural production in the south, and balancing the northern regime in the southeast by the Eastern Jin and Southern Dynasties. Therefore, it can be said that the reclamation and water conservancy construction in Sun Wu period is an important turning point in the history of agricultural production development in the middle and lower reaches of the Yangtze River and its south area, which has far-reaching historical significance.
(2) Irrigation and water conservancy during the Eastern Jin and Southern Dynasties
The Eastern Jin Dynasty and the Southern Dynasties ruled the vast areas south of Huaihe River and Hanshui River for a long time. Huaihe River and Hanshui River are the frontier areas of the North-South regime. Jiangnan area in the lower reaches of the Yangtze River is the political center and the most important economic center of the Eastern Jin and Southern Dynasties regime. The so-called "Baidu's investment is rare." . Due to political and military needs, the governments of the Eastern Jin and Southern Dynasties attached great importance to agricultural production in these two regions. Therefore, the management of farmland water conservancy is mainly concentrated in these two areas, especially in the south of the Yangtze River, which has always been the focus of development during the Eastern Jin and Southern Dynasties. In addition to these two key areas, Bashu area continues to develop on the basis of the original farmland water conservancy, and Lingnan area has gradually embarked on a faster development process.
1. Because there are many hills, hills, swamps and depressions in the Third Five-Year Plan area, the precipitation is unevenly distributed in time and space. For a long time, the highlands have been dry and the depressions have been flooded. Therefore, only by establishing a good irrigation and drainage system can we make full use of the rich agricultural resources here. In the long-term practice, the people in the south of the Yangtze River have created the characteristics of farmland water conservancy, which are mainly polder fields with water networks and hills and dams in mountainous areas. During the 270 years of the Eastern Jin Dynasty and the Southern Dynasties, two production armies, North and South, worked hard to reclaim and expand the land in the south of the Yangtze River. Both the water network project in the water town and the weir and pond project in the highland have made greater achievements on the basis of Sun Wu, laying a solid foundation for Jiangnan to become the economic center of China after the Tang Dynasty.
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(1) The Book of Southern Qi (Volume 26) The Biography of Wang Jingze.
(1) Water conservancy construction in Ningzhen area. Ningzhen area was the site of Danyang and Jinling counties at that time, and the terrain was mostly hills and hills, mostly low mountains and shallow hills, and the terrain fluctuated greatly. In case of heavy rain, mountain torrents wreak havoc and destroy the countryside; If it doesn't rain for a long time, the stream will stop flowing and there will be no water to irrigate. In view of the special natural environment, the working people in ancient times started a water conservancy irrigation undertaking with weir ponds as the main part, building ponds to stop water, storing water when it rains, and releasing water for irrigation when there is no rain on sunny days, thus forming countless small reservoirs. During the Eastern Jin Dynasty and Southern Dynasties, there were many weir projects in Ningzhen area. When talking about the water conservancy situation in this area, Wang Xiao of Jingling in Nanqi said: "This is not the only place in the old society to contain gutang." ① There are as many as 89 famous projects in the literature, most of which are located in Zhenjiang, Danyang, Jintan and Liyang.
First, practice the pond. Li Antang was built in front of Jinshi Du Nan, located in the northwest of Danyang County, 40 Li in Fiona Fang during the Tang Dynasty, also known as Lotus Lake. Chen Min "According to Jiangdong, it is necessary to cultivate and weave, and Jundi and Hezhi Malinxi will irrigate Yunyang, also known as practicing ponds and irrigating hundreds of hectares" (2). Li Antang accepts water from Lishan Mountain and Changshan Mountain, which can not only irrigate fields, but also help with transportation. It is a famous water conservancy hub on the Jiangnan Canal.
Second, Xinfengtang. Xinfengtang, also known as Xinfeng Lake, is near Xingfeng, about 20 miles north of Danyang County. It is a water storage irrigation project built in the early Eastern Jin Dynasty. In the fourth year of Daxing in the Eastern Jin Dynasty (32 1), Sharla Cheung, the civil history of Jinling, presided over the construction. "Lu Chuan" said: "At that time, the four counties under his jurisdiction lost their fields due to drought, and Lu was Li Qu Xinfeng Hall." At that time, * * * employed 2 1 1420 workers, showing the scale. "The mausoleum in the old Jin Dynasty was vast and sparsely populated, with few evil canals and many filthy fields". After the completion of the project, "more than 800 hectares of farmland have been irrigated, with a bumper harvest every year", which has promoted the development of agricultural production in this area.
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(1) The Book of Southern Qi (Volume 40) The Selected Works of Jingling Wang Chuan.
② ③ Yuanhe County Records (Volume 25).
Third, Chishan Hall. Chishantang is located in the southeast of Jiankang, the capital city, and is the most famous ancient weir pond around Jiankang. Chishantang, also known as Chishan Lake, is located about 30 miles southwest of Jurong County. Legend has it that it was completed in the second year of Sun Wu Chiwu (239), which initially solved the flood threat in this area, reserved relatively rich irrigation water sources for large areas of farmland outside the lake, and promoted the development of agricultural production in the beneficiary areas. By the Southern Dynasties, all dynasties had strengthened their governance. Xiao Qi was a famous period funded by the government and presided over by Shen Li when he became his ancestor in the Ming Dynasty. "It costs hundreds of thousands of materials to rebuild Chishanchi in Ming Di", and the Sui Dynasty was once defeated. During the Qide period of the Tang Dynasty, the county magistrate Yang repaired the old dike on the basis of Liang. In the 13th year of Dali (778), Wang Xin was rebuilt again. After reconstruction, the perimeter of Chishan pond is 120, and there are two gates to control the storage and discharge. At that time, the fields in Jurong and Shangyuan (now Nanjing) counties relied on this irrigation.
Besides large weirs, there are many medium weirs. According to Records of Geography of the New Tang Dynasty and Records of Zhenjiang of Shunzhi, the famous weir ponds at that time were: Tang Dan, located 28 miles northeast of Jintan County, built by Dan Man in Xiao Qi era; Wutang, located between Jintan and Danyang, 40 miles away from Tang and Zhou Dynasties, irrigates farmland in Jintan and Danyang counties, and Wu You presided over the construction in Liang Xiao; Xietang, located 25 miles north of Jintan County, was built by Tian Liang Shefa for nine years (510); The north-south inclined ponds, 30 miles southeast of Jintan, are irrigated by more than 1,000 mu each. They were built by Xie Dewei in the fifth year of Liang Pingtong (524) and rebuilt by Tang Wude. Guantang, three miles southeast of Jintan County, was built by Xie in the fifth year of Liang Datong (539). Louhu Lake is located in the southeast of Jiankang City 15 miles, and it is 10 miles per week, with an irrigation area of 20 hectares. It was built in the period of Sun Wu. Liu Song, Shen Qingzhi in this "wide animal husbandry" ③; Yingdan Lake in the north of Jiankang City irrigates 30 hectares of farmland ④; Sujun Lake, northwest of the city 15, week 10, irrigated land 12 hectares; Getang Lake, 72 miles east of the city, 7 miles a week, irrigates 40 hectares. Although these ponds are not as big as Li Antang, Xinfeng and Chishantang, they play an important role in agricultural production. In addition to large and medium-sized weirs built by the government, weirs dug by the people are even more difficult to calculate.
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(1) "Liang Shu" Volume 53 "Good Official Biography, Shen Li".
② ④ ⑤ Journal of Ding Jing Health Volume 18.
(3) The Biography of Song Shu Shen Qingzhi.
Count. More than 50 villages are named after ponds, weirs and lakes. In the Records of Danyang County compiled by Chaganlong and Guangxu, surnames are the most important. Although not all weir and pond projects were dug in the Six Dynasties, many were dug in the Six Dynasties or began to be dug in the Six Dynasties. In the twenty-first year of Yuanjia (444), there was a drought in the south of the Yangtze River, and the people were hungry and cold. "If they don't plant crops, they will starve." . However, in Jinling County, "the house of inheriting evil spirits is ubiquitous, and it is recovered after being lost, and the valley of Chen Ji is huge". This reflects that there are quite a few "north houses". Many large, medium and small weirs and ponds have played an important role in drought resistance and crop protection.
(2) Water conservancy in Taihu Lake area. During the Eastern Jin Dynasty and Southern Dynasties, water conservancy and farmland management in Taihu Lake area developed further on the basis of Sun Wu. This is mainly manifested in the construction of Tang Huo, dredging of Tongjiang Port, drainage and land reclamation in Taihu Lake area, and the proposal to solve the drainage channel of Taihu Lake.
Tang Huo, Tang Huo is located on the southeast edge of Taihu Lake, which is 90 miles long from Wang Ping to Huzhou. In volume 31 of Jiatai Wu Xingzhi, Wu was quoted as saying: "Jin Taishou kept it open and irrigated more than a thousand hectares of land." After the satrap Shen Youzhi's "Jia Jun, renamed the pool, can irrigate more than 2000 hectares" (2). In the south of the Yangtze River, "all famous places meet the land by water". Think of the lake in the name of plenty of water and build a pool in the name of water storage. Due to the special location of Tang Huo, its banks have actually become the levees on the southeast bank of Taihu Lake, which has played a role in preventing the flooding of Taihu Lake. Its Tanghe River has become a drainage and irrigation ditch, and it will stagnate the flood after a long period of rain. When the weather is dry, store water to irrigate the farmland under the pond. Therefore, the construction of Tang Huo promotes the development and utilization of seawater resources along the southeast coast of Taihu Lake.
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(1) The Book of Song Dynasty (Volume 91), The Biography of Xiaoyi, Geng Xu.
(2) "Yuanhe County Records" Volume 25.
(3) "Yongle Dadian" Volume 2276 "Tang" cited ".
(4) "Lotus Lake Records" (Volume 8) "Please fix the Lotus Lake inscription".
Dredging of Tongjiang Port. The northeast of Taihu Plain is adjacent to the Yangtze River, and the terrain is slightly inclined from northeast to southwest. Highlands suffer from drought and lowlands suffer from waterlogging. In the fourth year of Taikang in the Western Jin Dynasty (283), Yu Hai County (now Changshu City) was still a small county with a sparse population. In order to make use of the tidal resources of the river and eliminate the flood disaster, the working people here dig Tongjiang Gangpu along the river and build soil around the low-lying areas. When I arrived at Liang Xiao, "there are 24 rivers in Gao Xiang, which are connected with the tide, irrigating the source and not worrying about drought." The low fields in rural areas are all diked, which is enough to resist water and waterlogging. Because there is no worry about drought and flood, it is "Changshu", so in the sixth year of Datong (540), Yuhai County was changed to Changshu County. This shows that during the Eastern Jin and Southern Dynasties, great achievements were made in farmland management and water control in the northeast of Taihu Lake.
During the Eastern Jin Dynasty and the Southern Dynasties, the activities of turning lakes into fields also appeared in Taihu Lake area. In the northeast of Taihu Lake, there is the ancient Furong Lake Group between Wuxi and Wujin, which is known as the vast expanse of smoke and waves, facing each other for hundreds of miles. During the Jin and Yuan Dynasties, Zhang Gui, the historian of Jin Mausoleum, started a large-scale irrigation and water conservancy project nationwide, building Xinfengtang to irrigate the fields in Qu Axing and draining the fields in Furong Lake. But it was freezing, and the lake was not finished. This is an attempt to reclaim lake fields in Taihu Lake area. Although it was unsuccessful, it provided some motivation and reference for future generations. Later, in the 22nd year of Yuan Jia in Liu Song Dynasty (445), the local people successfully cultivated farmland in Yangxiu Lake Weir in Furong Lake area and obtained several hectares of fertile land. Reading Notes on Yu Fang (Volume 25): Yanghu Lake is 80 miles east and 32 miles north and south, and its north is connected with Yanrao Lake and Linjin Lake. * * * For the Three Lakes. Yuanjia, Liu Song, built a lake weir in the middle and gained hundreds of hectares of fertile land. "After recovering Yanghu, Yuanjia was ruled in Jinhu for twenty-four years. The rise of reclamation activities in Taihu Lake area reflects that the development of water and soil resources in Taihu Lake area has been gradually promoted from reclamation of Gaokang Plain to lake swamp, which is also a reflection of population growth and land intensification in Sanwu area during the Eastern Jin and Southern Dynasties.
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(1) Guangxu Chang Zhi Draft Volume 1.
(2) Kangxi's Changzhou Fuzhi quoted Nanxu.
(3) See Wang Jialun and Zhang Fang's History of Farmland Water Conservancy of China Agricultural Publishing House, 1990, 194.
During the Southern Dynasties, the drainage problem of Taihu Lake began to be exposed. Because Songjiang, the main drainage channel, was "silted up" and "flooded everywhere, causing flooding" during the Southern Dynasties. As a result, the land pollution and the Xing Wu area where the spring flow gathers will "be delayed, and before the rain, we will wander, or Fang Chun will drop out of farming, or get married in autumn, and our family will suffer." It shows that poor drainage has caused serious damage to agricultural production in this area. It seems that the traditional pond building and water plugging can no longer meet the new needs. Therefore, it is imperative to dredge and increase drainage channels. To this end, the Southern Dynasties government twice proposed a plan to increase the drainage channels in the lower reaches of Taihu Lake. During the Song and Yuanjia Dynasties, Wang Liujun, the secretariat of Yangzhou, decided to "open Gu Cao Lake from Guxi, Wu Kang, and reach the sea for hundreds of miles, crossing the canal". Mi Zhu made bamboo, which is more than twenty miles east of Deqing County today. At that time, I probably wanted to drain the water from the Tiaoxi River basin, which leads eastward to Taihu Lake, and then open a canal to Hangzhou Bay. Yao Jiao has been surveying here for more than 20 years. In the eleventh year of Yuanjia, he proposed this plan to the court, but after the merger, the court thought it was incomplete. In the twenty-second year of Yuanjia, Yao Jiao proposed it again, groped with the government and drew a pattern. It is considered feasible after examination, and its benefits can reach four counties. In order to be prudent, a small canal was opened as a pilot. At that time, migrant workers in Wucheng, Wu Kang and Dong Qian counties were mobilized to open small canals. But this project didn't succeed in the end. Another time was in the second year of Datong, Liang Zhong (530), because "Xing Wu County suffered from repeated floods and lost its harvest", some people suggested that "it was a great blasphemy to drain Zhejiang". The government sent Wang Yang and others to plan and organize soldiers in Xing Wu, Yixing and Wu Jun to "ditch and stop diarrhea". Zhenze is Taihu Lake, and the purpose of "guiding relief and zhenze" is to discharge the flood of Taihu Lake, and the purpose is to "save Xing Wu from repeated floods". However, due to the opposition of Prince Xiao Tong, this plan failed to be implemented. Although the two plans of canal opening and flood discharge of the Southern Dynasties government were not realized, it reflected that people had noticed the way out of the flood and sought the solution in the process of developing and utilizing the water and soil resources of Taihu Lake at that time, which had a great influence on future generations. From the Tang and Song Dynasties until today, the construction and maintenance of Taihu Lake water system is still an important guarantee for agricultural production in Taihu Lake area.
(3) Irrigation and water conservancy in Huiji District. Ningshao area belongs to Huiji County, one of the three Wu Dynasties in Eastern Jin Dynasty and Southern Dynasties. Because of its long history of development, superior natural conditions and relatively developed agricultural production. By the time of Liu and Song Dynasties, there had been a contradiction between "a small land and a small population" in Shanyin County, and the land price could be comparable to that in Guanzhong area. This requires further expansion of cultivated land area, improvement of water conservancy conditions and development of agricultural production.
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(1) The Book of Song Dynasty (Volume 99) The Legend of Two Bears Shixing Wang Junchuan.
(2) "Liang Shu" Volume 8 "The Legend of Prince Zhao Ming".
(3) The Book of Song Dynasty Volume May 4th Biography of Kong Ji Hong with Kong Ling Fu attached.
Jianhu Lake, built in the 5th year of Yonghe in the Eastern Han Dynasty (140), with its huge storage capacity, has stored the water of Huiji Mountain, basically solved the flood threat of Huiji Plain, and reserved sufficient irrigation resources for this area. During the Eastern Jin Dynasty and Southern Dynasties, the irrigation system in irrigation areas was further improved, mainly in the digging of grass canals in eastern Zhejiang. According to Jiatai Huijizhi, when Situ He Xun was Huiji County in Jin Dynasty, canals were dug to irrigate fields. He Xun presided over the canal digging at the end of the Western Jin Dynasty and the beginning of the Eastern Jin Dynasty. The purpose of the canal digging was to meet the needs of farmland irrigation. This canal starts from Xiling (now Xixing Town, Xiaoshan) in the west, passes through Huiji County in the southeast and reaches Cao 'e River in the east, with a total length of about 200 Li, which is roughly parallel to Jianhu Pool. Therefore, it has actually become an east-west main canal in Jianhu Irrigation District. This main canal and many original north-south rivers form a staggered pattern, which not only expands the irrigation area, but also facilitates the adjustment of water quantity between them, making the facilities and layout of the irrigation area more perfect. The excavation of this canal is of great significance in the history of water conservancy development in this area.
During the Eastern Jin Dynasty, Zhang Ju County (now southeast of Yuyao) was restored and rebuilt. The Biography of Confucius in the Book of Jin records that, when the internal history is to be reviewed, "there are old evils in Zhang Ju County, which have been destroyed for hundreds of years. I am happy to patrol, repair old weirs and irrigate more than 200 hectares of fields, all of which have become good deals. " There is also a big project in this period, that is, the development and utilization of long lakes. Notes on Water Classics Zhejiang Water: "Zhejiang is also in the northeast, with a long lake mouth, five miles of Huguang, 130 miles of east and west, and 69 boiling water gates along the lake, which irrigates thousands of hectares." The setting of sluice is very important for regulating water quantity and preventing drought and flood.
The seawall construction along the northern coast of Huiji County is also of great significance for maintaining the smooth progress of agricultural production in this area. The northern part of Huiji County is adjacent to the sea, and the tide is flooding, salinizing water sources and excluding land, which has a negative impact on local agriculture. Therefore, Huiji people built seawalls along the coast to resist the tide. Before the Six Dynasties, with the development of farmland in coastal areas, sporadic seawalls appeared. During the Six Dynasties, especially after the Eastern Jin Dynasty, a systematic seawall project seems to have basically taken shape. It is recorded in Geography of New Tang Dynasty and Records of Jiatai Huiji that there is a seawall in the northeast of Huiji, which was built on the basis of the original seawall in the tenth year of Tang Kaiyuan (722). This shows that hundreds of miles of seawalls in the north of Huiji existed before Kaiyuan. Although there are few documents about the construction of Huiji seawall before Kaiyuan, judging from some scattered materials and the background at that time, the large-scale construction of Huiji seawall should be in the Eastern Jin and Southern Dynasties. "Biography of King Jingze of the Southern Qi Dynasty" said: "There are lakes and seas near the soil, and the people have no scholars, and they all protect the pond." Moreover, there is also a special "weir pond ding", which is engaged in the construction of weir pond projects. The "pond" mentioned here refers to seawalls and dams of lakes and ponds. The large-scale reconstruction of weirs and ponds must include the construction of seawalls. Otherwise, only canals and river networks are dredged, and there is no systematic seawall to block tide and remove salt, and the low-humidity and salty mountain plain will not become a "fertile soil" for an acre of gold.