In this research, construction of the support system of the new navigational information aiming at marine accident prevention aims in marine traffic of a vessel. The method about the visual information service using omnidirectional camera as the first report was proposed. That is, the position information on the point is added to the image grabbed with omnidirectional camera, and, finally they are indicated by integrated on Geographic Information System(GIS). Thereby, in addition to two dimension information, such as a chart usually used, a navigation person can acquire more effective information by visualizing surrounding environment especially at significant point. Therefore, this information is very effective.
 Furthermore, it can contribute also to marine accident prevention as offer of the voyage information which decreases a navigation persons stress by use of carrying out the navigational simulation of the ocean space which sails for the first time before a departure.

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 This study developed an interactive information system that provides wind and wave prediction for offshore wind farms and other ocean activities. High wind during wind turbine operation could lead to damage of rotor blades requiring two to three days offline during repair. Long range wind and wave forecast one week in advance is necessary to successfully schedule turbine operation and maintenance. Short range detailed informational forecast one day in advance ensure worker safety on location as well as during commutes to and from the floating wind farm sites. The present information system gives information for user selected areas and lead times with both visual animations and also time series graphs.

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 The Ichinomiya coast located at the south end of Kujukuri Beach is one of the most famous surfing spots in Japan. In particular, breaking wave conditions are appropriate for surfing in the area between No. 7 and No. 10 artificial headlands. In this study, the reason for the establishment of the Ichinomiya coast as a surf spot was investigated in terms of the wave refraction and diffraction effect of offshore reef.

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 Utilization and coastal environment assessments of the Sendai New Port area by surfers were examined in order to collect baseline data for improving the coastal environment. A field study and a questionnaire survey of surfers in the area were conducted at seven-day intervals in the summer at Sendai New Port over the seven-year period from 2004 to 2010 and in 2010. The findings revealed that approximately 10% of the surfers surveyed were women and that more surfers went surfing in the morning than in the afternoon. In addition, surfers primarily rode waves of between 1.3 m and 1.8 m, with the longest 1/3 wave duration being 11 to 18 seconds. In the questionnaire survey, approximately 30% of surfers felt that the coastal environment had been improved, had not changed, or had generally become more degraded in recent years, respectively.

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 Oblong rockfish, Sebastes oblongus, and red spotted grouper, Epinephelus akaara, one of the highpriced fishes, have been released for stock enhancement in Kagawa prefecture in Japan. Released artificial juveniles of these species are easily preyed by predators after release due to their vulnerable characteristics such as sluggish movement and defenseless behavior. This fact have led to poor recovery rate in stocking project of these species artificial juveniles in Kagawa prefecture over the past dozen years. Therefore, we propose the new protective shelter for released juveniles in this study for the sake of avoiding intense predation by overwhelming predators. This shelter also functions as nursery ground with both remarkable amount of adherent prey organisms on the porous substrate and dark comfortable rooms. It is characterized by the size of gaps that small released juveniles can easily hide in and enourmous strong predators hardly sneak into.

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 In order to contribute to the stabilization of fishery management and the sustainability of fishery resources, fishery development projecs have been carried out. However, about continuons monitoring surveys, it is not easy to assess these project effects on the relation between fishery and environment because of increasing research cost. In this study, we apply HEP(predictive model) to the environmental assessment in red sea bream fishery, the following conclusions are drawn. Of potential prey environment is improved, catches of red sea bream was increased. For about 20% of the total catch of red sea bream, improvement is suggested. Therefore, it is suggested that the model can be used for the environmental assessment of red sea bream.

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 In 2002, a project to construct a new freeway along the Okinosu shore, located in Tokushima Prefecture in southwestern Japan started. However, the process of this construction involved land reclamation along the shore line where the endangered tiger beetle Cicindela lewisi inhabited. In compensation for the loss of their original habitats, the creation of a new artificial shore in the adjacent area was planned. Observational surveys in the original habitats demonstrated that adult tiger beetles usually utilize the vegetated area in the upper part of the shore and their larvae make nesting holes in the bare sand area of relatively lower zone. For closely mimicking conditions of their original habitats, the direct transplantation of coastal vegetation and surface soil from the natural coast was conducted. After these fundamental arrangements for existence of the tiger beetle in the new shore were completed in 2007, a corridor was made between the newly created and the original habitats for facilitating their natural movements. In the summer of the same year, adult tiger beetles had been already observed in the created shore. In the next spring, the larvae and their nesting holes were also observed. Moreover, the numbers of the both adults and larvae still increased suggesting that this mitigation succeeded at that stage.
 On the other hand, the other main purpose of the shore creation is the provision of amenity space. However, the human use is often considered to be incompatible with the environmental conservation. We conducted the workshop for considering the rules of shore use and its management systems in 2009 including locals. We agreed on making the rules that restricts human activities to harmless level for tiger beetle activities. Then, fences was installed in 2010 and could successfully prevented shore users from entering the larval habitat.

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 Loggerhead turtle is an endangered marine species and a sort of index animal of marine and coastal environment. A decrease in the number of loggerhead turtle landing on a sandy beach was often explained as it was caused by shore protection in Japan. In addition, it was reported that widen a sandy beach by beach nourishment may cause an increase in the number of loggerhead turtle landing and nesting. However, the number of loggerhead turtle landing would change significantly independent from the shore protection including hard and soft structures. Therefore, this paper clarifies characteristics of short and long term changes in the number of landings. Then, new criterion, landing index, is introduced to explain long term change in loggerhead landings. The landing index is applied to correlate with the number of typhoon landings.

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 Yatsushiro bay has large tide level and been get the exuberant environment for the halophyte. However, the halophyte habitat in Yatsushiro Bay has been decreasing because of the development of the coastal zone. Recently, it is becoming popular among society to prevent the tidal flat and the biodiversity implementation. We conducted the field survey to clarify the halophyte of habitat and existing conditions in Yatsushiro Bay. As a result of this study, the halophyte has been existing in the small area of the sheltered water and the brackish waters. Atriplex gmelinii was exuberating place that low level of salt and high ground level.

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 The ecological-designed revetment in Ohama area in the Port of Akita, Japan (Ohama revetment) was implemented along the Sea of Japan with unique structural features. The revetment was designed for attempting to develop a macro algae bed as a spawning ground of sandfish. In this study, a set of field observation of environmental factors and an assemblage of marine organisms was conducted after completion of the revetment for a year. Low salinity in the water surface and decreasing relative light intensities with depth were observed around the revetment. Diatoms, chameleon goby (Tridentiger trigonocephalus), bivalve (Mytilus galloprovincialis), and sea cucumber (Stichopus japonica) were dominant species around the revetment. These results indicate that the water structure around the revetment had strong stratification, and the revetment functioned as a habitat for various marine organisms. Sandfish were sampled around the revetment; however, they did not spawn on the revetment. Macro algae are essencial substrates for sandfish spawning, but few macro algae have developed on the revetment because of strong stratification. An artificial spawning materials could provide altanative solu-tion for the case. This report described an initial situation; however, continuous monitoring is needed to determine the dynamics of the assemblage of marine organisms and to estimate its potential as a spawning site.

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 In the prefectural policy around the Seto Inland Sea, Zostera bed construction project has been conducted for the purpose of environmental conservation and improvement of fishery resources. However, coastal shallow area which is appropriate habitat for Zostera marina has been used for filled ground and harbor facilities. Therefore, it has been required new suitable sites for Zostera bed construction. In Tsuda bay in Kagawa Prefecture, the Zostera bed has expanded since Zostera bed has created behind detached breakwater in 1996. For this reason, the area behind detached breakwater is expected to be used for new site of Zostera bed creation.
 In this study, we evaluated the growth characteristic of Zostera marina and examined commercial application and development of Zostera bed creation method around coastal structure by 14-year observation result and numerical calculation. As a result, the area behind detached breakwater has been appropriate habitat for Zostera marina. On the other hand, it has been revealed that the calm area formed behind detached breakwater has caused obstructive factor of Zostera marina growth.

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 In order to establish a technology to restore an eelgrass bed in coastal waters with heavy sludge deposit, granulated fly ash were evaluated for their suitability as the artificial eelgrass bed materials and verified for the practicality by transplanting experiments of Zostera marina at Hiroshima Bay.
 No significant difference in the rooting and growth of Z. marina was observed between the artificial bed and the river sand bed used as the control. Although the artificial bed constructed at Hiroshima Bay had shown some subsidence immediately after the installation, the transplanted Z. marina, with reinforcement against erosion, had taken roots and proliferated into more than 200 shoots in a short period of time.
 These observations and results imply that the artificial eelgrass bed of granulated fly ash is applicable as effective means to restore the Z. marina bed with a limited number of seedlings available.

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 In the Kushiro port of Hokkaido, the rear step of shallow depth was made by using the dredged sand on the offshore breakwater. The purpose to set up the rear step is a creation of the seaweed bed in addition to the decrease of the transmission wave by the wave-overtopping and the cost reduction by the reinforcement of the main caisson.
 This study is about the seaweed that grows thickly on the rear step and the environment of light on the rear step. The results are as follows: A large seaweed bed with mainly kelp is formed. It has been understood that the seaweed grows only to the upper part of concrete blocks. In this place, the amount of the photon is enough for photosynthesis of the kelp. The seaweed bed has changed from mainly diatom to mainly kelp. The species swarming in the marine forest increase every year.

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 In Hakodate fishing port located in the southwest region of Hokkaido, there is a problem with the fishing activities at the landing wharf due to the invading wave and harbor disturbance caused by the overtopping waves from the north breakwater. And the large-scaled Brawn algae phaeophyte has been lost at the area in front of the north breakwater, then isoyake that dominant species change into sea urchin is occurring with frequency. Thus in regard to improvement of the north breakwater, we adopt the doubly-placed breakwater that put the submerged bank in front of gravity-type composite breakwater and add a feature of artificial formation of seaweed bed. In this research, we report a condition of the seaweed bed around the submerged bank by the monitoring survey after building of the submerged bank.

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 The north breakwater of Hakodate fishing port located in the southwest region of Hokkaido was built in the 60's and becoming superannuated. There is a problem with the safety mooring of fishing boats and pleasure boat by the overtopping waves. So in order to solve this problem, the improvement work of the north breakwater has implemented as of 2010. In terms of the improvement, we adopt the doubly-placed breakwater that put the submerged bank in front of gravity-type composite breakwater and add a feature of artificial formation of seaweed bed because of isoyake is occurring with frequency around the north breakwater. And we set the crest elevation of the submerged bank to D. L. -0.1m in consideration of the flow velocity that could control feeding behavior of sea urchin. In this research, we report a controlled effect of the wave's flow velocity around submerged bank by the wave and current observation after building of the submerged bank has been completed.

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 Extensive efforts have been made to remediate environment in enclosed bays since 1970s. First attempts to remediate environment had been started an acute based approach. In recent ten years, 'restoration with nature' or 'mitigate before compensate' approach becomes major strategic guidance for environmental remediation. It means, associated technologies have been also changed along with these directions. Thus, up to date targets are re-issued and a load map for achieving holistic "enclosed bay's environmental remediation" were discussed and presented in Symposium on Civil Engineering in the Ocean 2010-2011, JSCE. One of long-term target is set as a holistic engineering development with disaster prevention and use of environment.

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 Design methods and construction technologies of maritime structures in our country have been developed by many experiences learned from disasters. However, disasters induced by waves still have occurred even in recent years, and the cause is sometimes the same as that of past disasters, which indicates that we have not learned from disasters occurred before. In addition that, disasters caused by the increase of wave forces or superannuation of structures have also occurred.
 In the special session, recent disasters of maritime structures were reviewed and the direction of new development of design methods and construction technologies of maritime structures were discussed from the point of view of "learn from disasters and apply to future design and construction".

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