Milstein, A., Fish and Aquaculture Research Station, Dor, 308290, M.P. Hof HaCarmel, Israel
Zoran, M., Fish and Aquaculture Research Station, Dor, 308290, M.P. Hof HaCarmel, Israel
Krambeck, H.J., Max Planck Institute of Limnology, P.O. Box 165, Ploen, D-2320, Holstein, Germany

Dual-purpose reservoirs for field irrigation and fish culture are characterized by the simultaneous (a) increase in standing crop biomass and feeds during the fish culture period and (b) decrease of water level due to irrigation. This management practice affects stratification, which in turn affects water quality and may affect the fish stocked. To study the limnology of dual-purpose reservoirs, an extensive sampling programme including automatic continuous recording and manual water sampling in deep and shallow reservoirs was carried out. This paper describes limnological changes during the week in which a 3 month long seasonal stratification ended and fish kills occurred. Management implications of stratification are also discussed. The data presented are the first continuous records of this process in this particular type of water body. © 1995 Chapman & Hall.