ABSTRACT: The Purpose of this research is development of the sustainable method to recover the tidal flat polluted by the reductive matters due to leaching out and oxidizing the matters of the bottom soil with the oxygen rich sea water using tidal energy. The leaching out and oxidizing the reductive matters out ofthe bottom soil with the oxygen rich sea water were confirmed through batch test and column test in laboratory, and in field column test. The ratio of COD reduction due to leaching and oxidizing ofthe bottom soil in column tests, however, were not sufficient because of the low permeability of bottom soil consolidated by seepage pressure. The device was found necessary to keep or increase the permeability of bottom soil during leaching.

ABSTRACT : The Volume of fluid method is effective in accurate calculation of fluid movement. This paper describes a treatment as a moving boundary of a floating body, and the reproducibility of the nonlinear wave force which acts on the floating body in order to use this method for the coupled analysis of the floating body and fluid. A free fall of a rigid body into a still water and a drift of a free floating body are calculated to examine the validity of the processing method of a moving boundary. In order to show the reproducibility of a nonlinear wave force, the over-topping wave profiles and forces on a fixed floating body are calculated, and these results are compared with the model experiments. Consideration of these results showed that the VOF method is effective in the coupled analysis of floating body and fluid.

ABSTRACT : In Japan, sandy beach has been rapidly disappearing, resulting in the artificial coastline protected with many hard structures . The cause was said to be the decrease of sand supply, obstruction of longshore sand transport and the beach changes induced by the formation of wave shadow zone by port breakwaters. In this study, the importance of other factors such as the disappearance of sandy beach due to the seaward advance of coastal forest and land use is described . The long-term changes of coastal zone are studied through the comparison of past aerial photographs, as well as the analysis of the disappearance of sandy beach triggered by the human activity, selecting Kujukuri beach as the example.

ABSTRACT:The purpose of this study is to clarify the relation between the result of CVM and the recognizability of object. Therefore, we chose two tidal flats as an evaluation object. One of the objects is ISAHAYA BAY tidal flats that is very famous . Another one is ARAO BAY tidal flats that is unnamed. We executed the questionnaire survey to I 050 people in three cities (Tokyo, Fukuoka City, and Sapporo City) . As a result, it has been understood that the recognizability of object hardly influences the result of CVM.

ABSTRACT:Local coastal zone management (CZM) is becoming one of the more important issues after major legal revisions of coastal laws in Japan. Concerned in the management process, participation has accelerated particularly in the local level. This article discusses participation and autonomy with particular interest in open source CZM. The author explores the concepts of open source management and autonomy of management system based on a case study of coastal forest conservation at Syonai coast in Yamagata. The transitional stages of participation and the relationship with autonomy of the system are observed. It has also been identified that the roles of the intermediary and the interpreter are important to facilitate the development process of management. In addition, a circuit model that explains the transformational changes in CZM is used to describe these roles. The author believes that the open source approach can be a unique and effective tool for designing a local coastal zone management system. It is believed that this article will contribute to the local coastal zone management development.