We investigated the survival, growth, and maturity of the rainbow trout Oncorhynchus mykiss reared in deep seawater (DSW) and surface seawater (SSW) pumped from depths of 687 m and 24 m, from Suruga Bay. From November 2006 to April 2007, 52 and 51 fishes (average body weight, 90 g and 96 g, respectively) were reared in heated DSW at a temperature of 15°C and in SSW at natural temperature (12-16°C). As a result, the growth rates of the fishes reared in heated DSW and SSW, were 1.1% and 1.2% per day, respectively, and the survival rates were 48% and 41%, respectively. From February to April 2007, 32 fishes (average body weight, 378 g) were reared in DSW at natural temperature (7°C). The growth rate was 0.0% per day, and the survival rates was 88%. From June 2007, 10 fishes that survived in heated DSW (average body weight, 671 g) and DSW at natural temperature (average body weight, 377 g) were reared in heated DSW (15°C). In November 2007, the average body weight of these fishes was 1.96 kg and 1.29 kg, respectively, and their maturity rates were 71% and 29%, respectively. The fresh meat of mature female fishes was vermilion in color, but that of mature male fishes was a pale beige color. In April 2008, the maximum body weight of fish that survived in DSW at natural temperature was 3.42 kg before maturation. From June 2007, 6 fishes that survived in SSW (average body weight, 883 g) were reared in SSW. However, all the fishes died by the end of July. Although the techniques for restraining the maturation of fishes need to be improved, these findings demonstrate the possibility of rearing large rainbow trout by using DSW.

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We attempted to develop a tank culture method for growing Sagarame Eisenia arborea by using deep seawater from Suruga Bay; For this purpose, we employed the mass-culture method using free-living sporophytes. Five experimental setups were created in the laboratory; the sporophytes were cultured at various cultivation densities (1.65-4.80 kg/kL) and had leaves of various blade lengths (19-50 mm). They were grown in polycarbonate tanks of 0.1 kL, 0.5 kL and 1 kL volume under natural daylight conditions for 28-48 days. Blade lengths and wet weights of all the culture samples under different setups were found to have increased, and the wet weights of cultures in each setup increased by 3.55-7.62 kg. Cultivation densities and the relative growth rates in blade lengths or wet weights showed negative linear correlations (blade length: y=-0.40x+3.81, r=0.64, p<0.05; wet weight: y=-0.73x+9.66, r=0.79, p<0.01) under same daily light quantity level. On the basis of these results, we think that tank culture of this kelp species with a high growth rate is possible if it is cultured at the density of 2 kg/kL or less.

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The Fisheries Research Institute (FRI) of COA in Taiwan is constructing another aquatic genetic resources center at Chihpen, Taitung County. The purpose of the center is to use deep ocean water with advanced aquaculture and marine biotechnology to preserve and breed important species to produce the superior seeds. It has been scheduled to complete the installation of all facilities by 2011. Currently, deep ocean water is obtained from private companies to carry out the related studies on algae culture. The main mission of the center includes studies on: (1) Breeding of economically important fishes and shellfishes, (2) Development of high functional algal products, (3) Development of high functional fisheries products, and (4) Development of low temperature related agriculture products.

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In Taiwan, industrial technology researches of deep ocean water (DOW) utilization were carried out by several research centers and universities under financial support from government since 2005, and were focused on three fields such as marine environmental monitoring and information management; development of raw materials with high commercial value, and biotechnology and green energy. In this paper, some applications were introduced such as development of domestic equipment for producing DOW raw materials, combination of local products with DOW, development of cosmetics and medical raw materials (e.g. extracting alginate and phycobiliprotein from seaweed), and pilot studies of green energy (e.g. algal cultivation for oil production, CO₂ fixation, and low-temperature energy utilization). As mentioned above, the utilization of DOW in Taiwan started from retaining raw materials through applications of fabricated food and now shifted to high value products and renewable energy. It has also shown a strong ambition for the future development of multiple-purpose utilization of deep ocean water resources in Taiwan.

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South Korea is blessed with a huge exclusive economic zone (EEZ) of oceans and coastal areas where we have developed human activities and present economical progress. Coastal oceans, wetlands and tidal flats have been reduced owing to increasing reclamation. Also, the shortage of freshwater is serious in South Korea. Accordingly, the government started to utilize deep ocean water (DOW) in 2000. Afterwards, infrastructures including the deep ocean water research center and the shore based facility were established in 2005. A five-year project, funded by the Ministry of Land, Transport and Maritime Affairs of Korea, began in Kosung using two types of DOWs pumped at a rate of 1,100 tons per day from depths of 300 m and 500 m and pooled into large tanks. Also, surface water is separately taken from the coast nearby. In addition, Ulleung-do deep ocean water factory owned by a private company, Panaburu, pumped 3,000 tons of DOW per day from a depth of 1,500 m through a pipe of 7,500 m in length. DOW is used for research and development of various purposes in South Korea.

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In order to strengthen present society, renewable resources of deep ocean water (DOW) have been model-analyzed in a case of resort being planed in Taiwan. After using the low temperature energy of 580,000 m³/day of DOW for air-conditioning of buildings with energy saving of 87%, a further energy saving of 63% is expected for cooling an electric generator by the heated DOW. Electricity of 613 MWh/year is expected to be generated by the thermal conversion of temperature difference between the waste heat derived from combusting garbage and DOW, and a possibility of temperate vegetable and fruit production was also checked under tropical climate by cooling soil with DOW. By supplying tap water of 42,000 m³/day for 160,000 people in the resort as well as the neighbors produced by desalination of DOW, a significant saving of resources could be expected compared using surface seawater. DOW will finally be discharged to the sea after removing the nutrient by cultivating seaweeds. The present study is a model analysis of saving energy and resources due to multi-step utilization of DOW resources.

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