关键词: 汾河水库控制流域, 径流量, 洪水特性

Abstract:

The variation of runoff and its reasons in the watershed controlled by the Fenhe reservoir are analyzed based on the long-term hydrological records during the years from 1970 to 2004. The results show that the high-flow year, moderate-flow year and the low-flow year are not in phase, more high-flow and moderate-flow year in 1970s and 1980s, more low-flow after 1980s in Jingle and Shangjingyou station. The main reasons were more precipitation before 1990, and the less precipitation and the water-and-soil conservation measures after 1990. Flood running concentrated in July and August. Entering 1990s, the frequency of extreme flood and drought events increased. The flood runoff change is mainly controlled by precipitation variation and landforms. Flood forecast, selection of the storage time, and the operation pattern of the reservoir are the key for flood resources usage. In this study, the design flood peaks under different recurring periods are computed for the controlled station.

Key words: watershed controlled by the Fenhe reservoir, runoff, flood regime