ABSTRACT：In this study, the change in dissolved oxygen concentration and oxygen evolution in water by supplying light with Light Emitting Diode (LED) was investigated on the column experiments. Watertight LEDs were used in this experiment. In this sutdy, the range of photon flux density was 52~133 μmol/m²/s. From the column experiment results, it was found that the dissolved oxygen concentration would be increased through the photosynthesis of benthic diatom by supplying light with LED in the presence of H₂S. It was also suggested that the favorable photon flux density would be the range of 50~180 μmol/m²/s in order to generate oxygen over a long period of time. Therefore, it should be possible to improve the condition of anoxic bottom water and reductive sediment surface by supplying light with LED.

ABSTRACT: Fundamental ecological features of eight major surf zone fish as Engraulis japonicus, Mugil cephalus cephalus, Hypoatherina valenciennei, Lateolabrax latus, Sillago japonica, Paralichthys olivaceus, Paraplagusia japonica and Takifugu niphobles occurred in the surf zone in an open sandy shore at Fukiagehama, southern Kyushu Island based on a long-term beach seining research from 2000 to 2010 used experimental large-scaled surf net were studied. Large fluctuations in number of fish caught and percentage occurrence and measurable increase of percentage occurrence with number of hauls suggest to beach conservation projects careful consideration to designing number of sampling occasions and duration of the survey. Observed larger body sizes and developmental stage in the surf zone fish than those reported in the previous studies indicate that the surf zone functions as habitat for the surf zone fish of wide range of developmental period from post-larval to adult stages.

ABSTRACT：Channel cleaning is essential operation for early restoration of port function after a large tsunami disaster. It is very important to prepare a planning and equipment integral for such clearing operations, with the anticipation of a great earthquake with tsunami like East-South-sea Great Earthquake in the future. Therefore, this report proposes the means and integral equipment for the clearing operations learned from the experiences of East Japan Great Earthquake Disaster on March 11, 2011.

ABSTRACT : At the time of the large-scale tsunami by the 2011 off the Pacific coast of Tohoku earthquake, many ships were obliged to anchoring. In the Tokyo Bay, many small ships anchored at Nakanose, offshore of Kisarazu etc. Therefore, it was difficult for large ships, which takes time to leave ports, to look for anchoring area. Based on this condition, Ministry of Land, Infrastructure, Transport and Tourism promotes to establish the area for large ship anchoring, as part of overall earthquake and tsunami countermeasures at three major bays. This study intends to grasp anchoring area at the 2011 off the Pacific coast of Tohoku earthquake tsunami and to present a guide of occupied area for each anchoring ship attacked by large-scale tsunami by using satellite and land AIS data.

ABSTRACT: We measured the area and distribution of shallows in the port and harbor regions to investigate the effect to which these shallows serve as habitats for organisms. The measurements were carried out at the canals in Tokyo Port in 2011. We used a wide swath bathymetry system to measure the topography below sea level and a laser measurement system to measure the topography above sea level. Shallows (< 3 m depth) covered an area of 7.1×10⁵ m², 18.0% of the canals. This area was equal to about 50% of the area of the Sanbanze tidal flat. The percentage of water area with a shallow above 10% was about 80% of the total water area. The high percentage indicated that the shallows were widely distributed in the canals. The results suggest that we can create a wide-ranging ecosystem network and sustainable habitat in consideration of the life cycle of organisms in the canals.

ABSTRACT: Redevelopment of old piers and yards is one of the most important issues of large port cities, because redevelopment there has been expected to play an important role in stimulating and reinforcing the economic activities of the neighboring Central Business District ( C.B.D ). It is not easy to reconstruct old isolated area into new commerce and business zone, due to the limited access to neighboring C.B.D , the large scale of area lot and cost for infrastructures .

Based on the analysis of the three typical redevelopments of old piers and yards in Japan , it is concluded that ;1.The public sector had better to construct pedestrian networks, arterial roads and ramps to improve the access to the existing C.B.Ds and the stations;2 .The public sector had better to find out a key developer at the initial stage of making the master plan to execute redevelopment in cooperation with private developers ;3 .The planning and the implementation should be accordance with master plan by public sector and development conception by private sector to elaborate characteristic development along waterfront.

ABSTRACT : In this paper, a simplified growth model taking into account the individual differences of the larvae of clam Ruditapes Philippinarum was developed, and proved the validity of the growth model reproducing the results of the observations shown in distribution of frequency of appearance of larvae of different shell lengths. Also, we created a vertical movement model taking into account the individual differences with the difference of density between the sea water and the larvae serving as the impetus. The numerical simulation using these model approximately reproduced.