Development of GIS using acoustic measurement methods for quick quantitative assessment of marine bioresources

本研究旨在建立基于地理信息系统的水生生物资源快速评价方法。我们用定量回声探测仪和声学测量仪器对尚未调查的中上层鱼类和海草/海藻进行了测量。我们利用分束式探测仪对日本专属经济区海山周围最重要的中上层经济鱼类--银鱼(Beryx Plendens)进行了定量化。我们使用多波束声纳和差分GPS绘制了精确的海山海底地形。这些数据被合并到系统中，该系统可以使用地理信息系统快速评估定量鱼类分布与海底地形之间的关系。我们还开发了一套系统，可以在便携式个人电脑的显示器上实时显示回声探测仪扫描的包括海草在内的底物。所开发的软件对来自测深仪和D-GPS的信号进行处理，并利用GPS对船位进行分类定位。我们对三陆海岸、神奈川县三浦半岛的海草和海藻以及地中海的波西多尼亚海床进行了实地调查。在这些地区也进行了海洋真理。在三里库海岸，我们研究了茎节藻的生态和生物量。此外，将地理信息系统应用于渔业科学和渔业海洋学研究中，对纳霍德卡溢油事故造成的潮间带生态系统污染的变化和沿海地区的管理进行了地理信息系统分析。声学测量需要高度专业化的知识才能使用，产生了大量的数据。因此，声学测量一直是估算资源的一种非常复杂的方法。建议用声学测量来估算渔业资源，因为它不受渔业活动的影响。我们的研究成功地开发了一种结合地理信息系统和声学测量数据的简便、快速的评估方法。我们计划开发另一种快速评估其他生命形式的海洋生物资源的方法。

This study aimed to develop quick assessment methods of aquatic living resources using Geographical Information System (GIS). We measured mesopelagic fishes and seagrass/seaweed beds, which haven't investigated, with quantitative echosounders and acoustic measurement instruments. We quantified alfonsin (Beryx splendens), one of the most important mesopelagic commercial fish around seamounts in Japanese exclusive economic zone by using a split-beam echosounder. We mapped precise bottom topography of seamounts with multibeam sonar and differential-GPS. These data were incorporated into the system that can quickly assess the relation between quantitative fish distribution and bottom topography using GIS. We also developed the system that can show substrate including seagrass scanned by echosounder on the display of portable personal computer in real time. The developed software processes signals from the echosounder and D-GPS and classify substrate localizing ship position with GPS. We made field surveys on seagrass and seaweed beds in Sanriku Coast, in Miura Peninsula of Kanagawa Prefecture and Posidonia beds in Mediterranean Sea. Sea truth was also done in these areas. In Sanriku Coast, we studied ecology and biomass of Zostera caulescens. In addition, we made analysis with GIS on change in intertidal ecosystem polluted by Nakhodka oil spill accident and management of coastal area as studies using GIS applied to fisheries science and fisheries oceanography. Acoustic survey has needed highly specialized knowledge for use and produced large quantity of data. Therefore acoustic survey has been very complicated method to estimate resources. Acoustic survey is recommended to estimate fisheries resources because it is independent from the fisheries activity. Our study succeeded to develop easy quick assessment methods integrating GIS and acoustic survey data. We plane to develop another quick assessment methods for other marine bioresosauces with variety of life forms.