Quantifying Environmental Flow in the Form of Pulse Flow for Fish Protection

Pulse flow, which includes base peak flow duration, occurrence time, and frequency, is a manifestation of environmental in rivers. This paper describes methodological framework for determining pulse based on an analysis fish spawning behavior presents its application to the second Songhua River northeastern China. Peak was determined hydrographic-habitat relationship conjunction with physical habitat simulation. The duration incubation period eggs. time frequency were suitable temperature spawning. differs from conventional methods dividing periods selecting target species corresponding period. Fish divided into cold-water fish, hypothermal-water warm-water according temperature, each month (April July) identified. For same period, relationships adhesive drifting eggs weighted determine flow. most April May research region 900 m3/s 1200 June July. Using proposed framework, ecological hydrograph July obtained by combining method Fifteen days, eight five days chosen as durations April, May, July, respectively. We recommend scheduling two high flows while limiting only one April. results show that this offers promising approach developing rivers variety species.