Experimental research on the life space of the deep-sea large-sized swift-moving benthic organisms

在深海海底部署了底部系泊的拍频捕获照相机海流计系统，以通过远程化学刺激和可能的听觉吸引海底快速移动的生物。本年度的实验重点是在KT-04-07和KT-04-10航次期间，在单一系泊系统上使用垂直系列诱饵诱捕器，研究深海底层鱼类和十足类的垂直迁移。（诱饵陷阱、摄像机、流速计和声学探测器，安装在带有浮标和压载物的框架上），以及一系列位于50米处的诱饵陷阱，距海底100米、200米和400米。底部系泊持续时间为24小时。摄像机记录了海底动物群的组成和生物量，底部诱饵诱捕器收集到的一般海底动物群组成和生物量与预期相符。在距海底200 m处采集了两条深海鳕鱼-最大物理蛙（Physiculus maximoviczi），并给出了200 m/24 h垂直迁移的实际数据。然而，垂直迁移者的组成部分只是深海海底栖息成员的一小部分。相模海槽的结果证明了另一个明显的事件。密集的重力流云团袭击了观测站，底部100米的水层被沉积物云团严重模糊，没有捕获到任何渔获物，也没有提供任何摄影记录。在距海底200米处采集的某些元素可以解释为重力流的回避。许多关于深海大型鱼类上游现象的报道，容易导致对许多底栖鱼类上游运动的高估。密集拖网平行试验表明：（1）上半深海区白天拖网和夜间拖网的区系组成存在细微差异;（2）随着生长，水深分带和食性沿着发生变化。这些研究结果发表在国内外期刊上。

Bottom-moored beat-trap-camera-current meter systems were deployed on the deep-sea floor to attract benthic swift-moving organisms by remote chemical stimuli and possibly by auditory sense. Experiments of this year were focused on the vertical migration of deep-sea demersal fishes and decapods using vertical series of baited-traps on a single mooring system during KT-04-07 and KT-04-10 cruises.Bottom-moored system consisted of a bottom base (bait-trap, camera, current meter and acoustic releaser mounted on a frame with buoys and ballast weights), and a series of bait traps situated 50m, 100m, 200m and 400m above bottom. Bottom mooring duration was 24 hours. The camera recorded and the bottom bait-trap collected ordinary benthic faunal composition and biomass as can be expected. Two deep-sea cods, Physiculus maximoviczi were collected 200m off bottom, and gave the actual data of 200m/24hrs vertical migration. However, the components of the vertical migrants were only a fraction of the members inhabiting the deep-sea floor. The results of the Sagami Trough evidenced another pronounced events. Dense clouds of gravity currents attacked the station, and the bottom 100m layer was severely blurred by the sediment clouds and collected no catch and gave no photographic records. Some elements collected 200m off the bottom can be interpreted as the avoidance of the gravity currents. Many reports of the rarely occurring swimming up of deep-sea macrourids are apt to lead to the overestimation of the swimming up movement of the many demersal fishes. These notion contradicts to the low density of midwater prey organisms.Parallel experiments of intensive trawling revealed, 1)subtle difference of the faunal composition in the daytime trawl and nighttime trawl on the upper bathyal zone, and 2)the change in bathymetrical zonation and food habit along with the growth. These results were published on the domestic and international journals.