The Important Impacts of Natural Changes and Human Activities on Flood Frequency and Water-use Guarantee Rate

摘要

By the calculation and analysis of the distribution changes of flow on some representative hydrological stations in the mainstream or branches of the Yellow River, it is found that the basic hydrological features (such as the maximum flood discharge, Annual runoff volume, flood season flow etc.) for the constructed, being constructing or constructed water project in any related area, are often interrelated in one region of the Yellow River basin or other basins. If the nature conditions change or human activities disturb, these parameters of features (such as mean value, Cv coefficient of deviation, skewness coefficient of skewness or Cs) will change relatively. It will result in the relative changes of flood frequency and water guaranteed in different sections of the river. Therefore, further analysis and research of quantitative changes is the basic prerequisite for the scientific decision-making, design, investment, effective management and utilization of water projects, and also plays an important and realistic role in flood and drought fighting.