Recognition of hydrologic cycle and water-silt relation in ancient China

In ancient China, the Chinese people had made special achievments and contributions in many fields of hydrologic science including hydrologic cycle, runoff, silt, water-silt relation as well as for their observations, records and their rationalization.More than 2000 years ago, the Chinese people described the hydrologic cycle by using "circle concept" which is completely coinsided with the scientific definition used nowadays.The records about historic hydrology including literatures and carving marks of extraordinary high or low water levels along river banks or on the river beds, provide not only the evidence of historic floods or low stages but also specially important data for planning and design of large scale hydraulic and hydropower projects in China.