Restoration and Conservation of Brackish Environments after the Termination of the Nakaumi Reclamation Project

为了恢复和可持续利用因填海工程而严重恶化的中umi湖的微咸环境，进行了以下研究：(A)探索和分析现有数据，(B)主要利用生态技术方法积累新数据，并在这些数据的基础上进行环境模拟，以及(C)采取措施保护和管理这个微咸泻湖的健康环境。研究活动的重点领域包括：沿海生态系统、水质、海底环境和环境遥感。沿海生态系统：双壳类菲律宾Ruditapes philippine arum的死亡生物学条件不仅受水质的控制，还受湖盆形状、藻华和水生植物的腐生作用的控制。本研究为这种滤食性双壳类动物的保护提供了重要的指导，进而促进了水体的生物净化。水质：设计了河口水质长期监测所需的免维护观测单元和经济高效的数据传输系统。底部环境：根据沉积物岩心分析，在封闭的沿海泻湖中，当水深超过15m时，沉积物堆积速率小于1kg/m2/yr， TOC大于3%是永久亚氧至缺氧水的指标。在亚滨海地区，由于侵蚀作用，海底地形发生了很大的变化，大量的死海藻堆积在近海防波堤的内侧。环境遥感：利用卫星和航空传感器数据验证了沿海泻湖环境广域环境观测的有效性，从SAR数据（JERS-1和RADARSAT-1）解释的水面特征与风向和风速具有良好的相关性。这些结果应用于计算机模拟实验，研究了中海湖低代谢缺氧状况的缓解。2004年1月举行了一次国际研讨会，总结和传播该项目的成果。强调了以下特征：(1)长期监测的重要性；(2)公民共识的重要性；(3)任何经济效益分析都需要包括生态系统产品和服务的概念；(4)需要将这一问题的研究和教育计划结合起来。少

Working toward the restoration and sustainable utilization of the brackish environment of Lake Nakaumi, which has deteriorated significantly due to the reclamation project, the following studies were carried out ; (A)exploring and analyzing existing data, (B)accumulating new data mainly using a ecotechnological approach and running an environmental simulation based on these data, and (C)taking steps for conservation and management of a healthy environment in this brackish lagoon. The following areas were emphasized in research activities : coastal ecosystems, water quality, bottom environment and environmental remote sensing.Coastal ecosystem : The thanatobiologic condition of the bivalve Ruditapes philippinarum is controlled not only by water quality, but by lake basin shape, algal blooms, and the saprogenic effects of aquatic plants. This research provides important guidelines for the conservation of this filter-feeding bivalve, which will, in turn, promote bio-cleansing of the water … More column.Water quality : A maintenance-free observation unit and cost-effective data transmission system, necessary for long-term water quality monitoring in estuarine areas, was designed.Bottom environment : Based on sediment core analyses, an indicator of permanent sub-oxic to anoxic water is a sediment accumulation rate of less than 1kg/m2/yr and TOC greater than 3% when water depth is more than 15m in an enclosed coastal lagoon. In the sublittoral zone, the bottom topography was greatly modified by erosion and large masses of dead seaweed accumulated on the inner side of offshore breakwaters.Environmental remote sensing : The validity of wide-area environmental observation of the coastal lagoon environment was tested using satellite and airborne sensor data, Water-surface signatures interpreted from SAR data (JERS-1 and RADARSAT-1) showed a good correlation with wind direction and speed.These results were applied to computer simulation experiments investigating the alleviation of hypolimnetic anoxic conditions in Lake Nakaumi.In January of 2004 an international seminar was held to summarize and disseminate the results of this project. The following features were emphasized : (1)the importance of long-term monitoring, (2)the importance of citizen's consensus, (3)the need for any economic benefit analysis to include the concept of ecosystem goods and services, and (4)the need for the integration of research and education programs on this problem. Less