A comprehensive field survey and analysis on a physical and ecological system of coral reef environment under adjacent land and ocean influence

1)2000年7月至9月和2001年7月在石垣岛白穗礁进行了野外观测，利用装有各种测井仪型传感器的系泊浮标系统和安装GPS的小型漂流器等进行了野外观测，以了解白穗礁的海流、波浪、温度、盐度、浊度等特征。在珊瑚礁中发现，由珊瑚礁地形的空间不均匀性，如S1 ze和通道的位置，浅滩和礁缘。2）较小规模的测量，以观察3-在同一时期，在白穗礁也得到了珊瑚群落周围的局部流场和温度场，揭示了珊瑚的特征，以及珊瑚可能比珊瑚沙更有效地吸收光线的事实。建立了一个以降雨、植被、土壤类型和地形等为输入数据的数值模型， 关于我们 根据2000年6月以来Todoroki河的浊度时间历史的现场数据进行验证。4）用于研究珊瑚幼虫的长距离运输。这可能对1998年夏季因大规模漂白而严重受损的珊瑚礁的恢复过程很重要，新开发的GPS安装的漂移器和其他设备用于澄清海洋的物理过程-Kerama Ms.与冲绳西海岸连接区域的表面流和示踪剂的拉格朗日轨迹此外，在实验室中研究了幼虫在水柱中的行为和在底部的沉降。这些结果表明，Kerama Isls。5）2001年7月和8月在Fukido和Miyara河蛾区进行了野外观测，以阐明红树林和海草区物理环境的基本特征。6）根据这些野外数据，建立了模拟礁内浅水湍流的数值模型，7）建立了珊瑚冠层三维光学模型，作为遥感珊瑚礁底栖生物覆盖等环境的基础理论工具。少

1) Field observations using moored buoy systems with various logger-type sensors, GPS-installed small drifters and others were performed at Shiraho reef in Ishigaki Island in July to September 2000 and July in 2001to find characteristics of currents, waves, temperature salinity, turbidity, etc. The hydrodynamic feature, especially the mean flow field, in the reef are found to be governed by the spatial non-uniformity of the reef topography such as the S1ze and locations of the channels, shoals and reef edges.2) A smaller scale measurement to observe 3-D local current and temperature fields around coral communities was made also at Shiraho reef in the same period, revealing their characteristic features and the fact that corals may absorb light more effectively than coral sands.3) The watershed-based numerical model to simulate soil erosion and subsequent discharge into adjacent reef areas with input data such as precipitation, vegetation, soil type and topography has been developed and … More validated with the field data on time histories of turbidity at the Todoroki river taken continuously from June 2000.4) For examining the long-distance transport of coral larvae. which may be important in the restoration process of the heavily damaged coral reefs due to mass bleaching in 1998 summer a field measurement using an HF-ocean radar system, newly-developed GPS-installed drifters and others was performed to clarify the physical process of the sea-surface currents and the Lagrangian trajectories of tracers at the sea surface in the region connecting the Kerama Ms. and the west coast of the Okinawa Id. Besides larval behavior in the water column and settlement at the bottom were investigated in a laboratory. These results demonstrate that Kerama Isls. may act as a source area supplying appreciable amount of coral larvae to the west coast of Okinawa Isl.5) At Fukido and Miyara river moth areas in July and August 2001 a field observation was made to clarify the fundamental characteristics of physical environments of mangrove and sea-grass areas.6) With these field data, numerical models to simulate shallow water turbulent flows in the reef, which governs material and thermal transport in the reef, and coastal 3-D currents in a wide have been developed with the basis of SDS-Q3D model and POM-dual sigma coordinate model, respectively.7) As a basic theoretical tool for remote sensing of coral reef environments such as benthic cover, a 3-D optical model for coral canopy was developed. Less