This study clarified the structures and seasonal changes of the annual Zostera marina population from April 2003 to November 2004, growing at Tategami-ura, Ago bay, Mie prefecture. Productive structures showed the graminous types excluding flowering period (May-June). Biomass and shoot density reached maximum values in May-June. At that time, over 80% of shoots were flowering shoots. And then, all shoots were disappeared in summer. From October-November, a lot of seedlings recruited and grew to flowering shoots by next spring. Maximum daily net production showed 4.50 g m^-2 day^-1 in June, which was similar level to that of the perennial Zostera marina population. However, yearly net production (305.0 g m^-2 year^-1) showed lower than that of the perennial type. Yearly maximum biomass was 152.6 g m^-2, and production/biomass (P / B) ratio was 2.0. It is necessary to more research in the production because the biomass and shoot density of the annual population verify drastically year to year.

We investigated the oxygen consumption and resistance for hypoxia in captivity of coral trout grouper Plectropomus leopardus. The fish with an average bodyweight 3 g consumed 515, 667 and 654 mg/kg/h of oxygen at water temperature 25, 27 and 30℃, respectively. On the other hand, one with an average bodyweights 5 g consumed 468 and 804 mg/kg/h at 25 and 30℃. The former groups recorded a decrease in oxygen consumption rate from 5 mg/L. The latter groups recorded from 4 mg/L. In a water temperature ranges from 25 to 30℃, 3 g fish began to die at dissolved oxygen levels of 0.99 to 1.06 mg/L (oxygen saturation of 15.4 to 16.0%), while at 0.73 to 1.15 mg/L (oxygen saturation of 11.0 to 18.8%), 5 g fish groups began to die. This is a significant result and gives a scientific impact on hypoxia for coral trout grouper aquaculture.

the purpose of this study is to clarify how Company A of fisheries processing and sales Company A in N City, Yamaguchi Prefecture overcame the constraints and challenges of sixth industrialization, such as the existing industrial structure and the limitations of the capabilities of economic entities that many management entities face. In conclusion, with the cooperation of the fishery cooperative in Company A's efforts to become a sixth industrial, the fact that each employee was able to make use of their experience and know-how to overcome the constraints and issues. This is thought to have led to the establishment of the sixth industrialization.

In this study, focused on the waste heat energy from seafood processing plant as research to promote the use of unutilized energy. The waste heat energy from seafood processing plant contains large amounts of the high temperature waste gas from the production of fish cake, and the high temperature wastewater from the production of boiled whitebaits and bonito flakes. If these unutilized waste gases and wastewater could be recovered and utilized as the high heat sources, it would lead to significant energy savings. It is assumed that seawater will be used as the low heat source. Seafood processing plants are usually located close to the sea for processing fisheries caught in the sea, and we recommend the use of seawater as the cooling heat source. Therefore, it is necessary to design systems in consideration of the effects on the ocean environment in the area where seawater is discharged, which may lead to significant modification of the ocean environment. If the optimum flow rate of low heat source at maximum net power is identified, the pump power for seawater can be reduced and the flow rate of seawater into the heat exchanger can be minimized as needed, which is expected to reduce the amount of seawater contamination and lead to lower maintenance costs for the heat exchanger. As a result of this study, it was found that the optimum flow rate of low heat source exists for maximum net power and maximum turbine output. The maximum net power was higher when the temperature difference between inlet and outlet of low heat source was higher, while the maximum turbine output was higher when the temperature difference between inlet and outlet of low heat source was lower.

The author has previously developed and published energy and resource flow models focusing on the post-collection process of marine debris. These models were designed to examine the technical and economic feasibility of establishing businesses with energy systems. One of the previous studies examined the economic feasibility of a microgrid system combining a styrene oil conversion device from drifted styrofoam and a cogeneration system (CGS). The current study focuses on the “biomass gasification furnace and methanol synthesis furnace” technology, which has a proven track record with woody biomass. If this methanol synthesis furnace could be applied to drifting marine debris, it would be an option for providing energy to coastal facilities. In this study, an energy flow model was developed that can easily calculate the energy flow of a methanol synthesis furnace, CGS, and fuel supply system using biomethanol obtained from coastal biomass such as marine debris. If only marine debris is taken into account, the amount of biomass will be insufficient. For this reason, discarded fish and food residues from fishing ports and fish processing plants were also evaluated. Furthermore, this biomethanol can be used together with waste cooking oil to synthesize biodiesel fuel (FAME), enabling various applications including marine fuel. Using this energy model, the potential for energy self-sufficiency for coastal fisheries facilities (fishing ports, fish processing plants, and fishing boats) was calculated. The calculation results show energy selfsufficiency as a function of changes in biomass volume. However, they also found it difficult to be self-sufficient in electricity, heat, and fuel at the same time. Additionally, an optimization model was developed to determine the optimal size of the CGS, demonstrating the potential to improve the energy self-sufficiency of coastal fishery facilities.