Shuijing Zhu
《水经注》
Commentary on the Waterways Classic was written by the famous geographer and writer Li Daoyuan (469-527)of the Northern Wei Dynasty. Based on The Waterways Classic ,a book compiled in the Three Kingdoms period，Li Daoyuan added commentaries arid annotations and finished his book some twenty times the size of the original. This 40-volume work elaborates on the locations and attributes of over l (}Oti waterways，including detailed accounts of the ori- gins，drainage areas and destinations as well as the width of the river bed，the measurement of the waterfalls，the location of torrents，even the sediment concentration，the water level，the flow velocity and the ice formation period of each waterway. He corrected statistical errors in the original book with first-hand data he collected in his field investigations，especially for the water system in north China With 437 citations from other books and essays，Commentary on the Waterways Classic was the most exhaustive geographic work before the 6th century. Besides its achievements in geography，the book is a literary classic with vivid descriptions of the scenic beauty，the people and their customs along the waterways. Its prominence in geography and literature，even in archeology and hydrography has made it a specialized topic for academic research since the Qing Dynasty.
作者郦道元，北魏皇兴三年( 469 )生，是地理学家、散文家。他以《水经》为纲（三国时期成书)，作了20倍于原书的补充和发展，完成了地理学专著《水经注》。《水经注》是一部详尽记载河流水道的地理著作共计40卷,30余万字。全书资料详备，不仅记载了1 000多条河流水道，而且还将河道的起源、流程、归宿，沿途河床宽窄、瀑布、急流甚至河流的含沙量、水位、流速、冰期等情况都作了细致的描绘。其中以叙述北方水系最为精洋，通过亲身调查研究，对前人论化误多所厘止，因当时南北政权利对峙，郦道元对南方个别水流情况不熟，不免有某些疏误。所引书籍多达437种，是6世纪前我国最全面系统的综合性地理著作至于沿途地区的自然地理、人文、风俗、人物掌故等情况，郦道元也作了繁片博引，《水经注》一书集中国6世纪以前地理学著作之人成，为水文地理学、考占学、水利学等方面的重要文献。《水经注》的研究历来受到重视，在清代已成为一门专门学问。
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