| 摘要 |
<p>PURPOSE:To suppress the propagation of plankton by cooling epilimnion by pumping up low temp. water from a deep-water layer to supply the same to the epilimnion forming a stable layer in a high temp. state. CONSTITUTION:The water sucked from the tip of a water sucking pipe 4 is passed through a pump 5 and a water distribution pipe 6 to be sprinkled from a water sprinkling pipe 7. Since the water temp. of the epilimnion on the surface of a reservoir to which the water of a deep-water layer is sprinkled falls largely and the quantity of solar radiation reaching the surface of the reservoir is also reduced, the activity of plankton growing in crowds within a predetermined radius centering around of a sprinkler 1 is weakened and the propagation thereof can be suppressed. The water of the deep-water layer sinks downwardly and, at this time, plankton in the surface layer of the reservoir is together sunk. Since the sunk plankton can not receive solar radiation sufficiently, the propagation thereof can be stopped.</p> |
