| 摘要 |
<p>The tunnel allows migratory fish to get past obstacles in the river. It has a tube (1) forming a tunnel which is placed in the drop of water at an angle to the horizontal surface of the water. The upper (8) and lower (2) ends are placed in the water (7). Inside the tube there are partitions (4) with openings (6) which are large enough for the fish to pass through. The partitions are about 40 centimetres apart at right angles and parallel to the circumference of the tube. The tunnel has clear sections (5) to provide light in the tunnel. The diameter and length of the tube can be varied. The upper section (8) of the tube has a swans neck (3) to reduce the amount of debris entering the tunnel. The tunnel may also have bulging areas where the fish can rest.</p> |
