Subtidal rocky coasts of southwestern Hokkaido are known as long-standing urchindominated barren grounds where hard substrata are extensively covered with nongeniculate coralline algae (NCA). In the previous study, the NCA-covered cobbles collected from one of the barren grounds (3 m in depth) were colonized by kelp and other algae when kept in an aquarium with snails in flowing warmed deep-sea water (w-DSW) of Toyama Bay (11°C). In the present study, NCA-covered cobbles and crusts of Lithophyllum yessoense (dominant NCA) were kept in flowing w-DSW after zoospores of the kelp Laminaria religiosa were settled. In the snail treatment, these substrata remained free from diatoms by snail grazing; kelp and othermacroalgae appeared from various refuges on cobbles (e.g., undersides of cobbles, interspaces between NCA crusts or their protuberances and bases of rudimental macroalgal tufts) but not on NCA crusts. In control, diatom heavily colonized the cobbles and NCA crusts resulting in few growths of kelp; sporelings of L. yessoense were trapped in the‘diatom mats’, which may inhibit their recruitment. In another experiment, NCA-covered cobbles collected from deeper barren bottom (7 m in depth, boundary between hard and soft substrata) were kept in w-DSW without settling kelp zoospores. As the result, Undaria pinnatifida and Costaria costata as well as L. religiosa appeared in the snail treatment while a few L. religiosa appeared in control. Appearance of a total of 22 species of macroalgae on NCA-covered cobbles in a series of studies strongly suggests that potential algal vegetations (e.g., growth-suppressed sporelings) are widespread in the barren ground and can be facilitated when nutrients and moderate grazer (diatom remover) are present. Although supply of kelp zoospores facilitates kelp recovery, multi-species bed formation should be aimed for the maintenance of stable community because macroalgal tufts function as refuges of kelp.

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Kume Island deep ocean water has a higher specific gravity than tap water or surface ocean water and therefore is expected to produce possible effects by higherwater pressure. In this study we observed the circulation of the rigtht vastus medialis muscle with a laser tissue blood-oxygen moniter and measured blood pressure when subjects were immersed to the xiphoid process in the Kume Island deep ocean water at 34°C. Ten males and 5 females served as subjects. Measurementswere made with the subjects in each of 5 conditions, that is in a standing, sitting, and lying supine on the ground, in standing position in tap water and in the Kume Island deep ocean water. The specific gravity of tap water and Kume Island deep ocean water were 1.00 g/cm³ and 1.03 g/cm³, respectively when measured using a gravimeter (YAGAMI) when measured.
An equilibration period was allowed for each subject, and measurements were taken only after heart rate stabilized (±1) for 30 sec. Blood pressure standing in the Kume Island deep ocean water (SBP; 113.54 ±13.45/DBP; 65.31±12.65 mmHg) was significantly lower than that sitting on the ground (127.23±12.85/81.38±10.44 mmHg). The total hemoglobin (HbT) levels in the vastus medialis muscle at right might reflect the variation in venous return with water pressure or posture. Since no significant difference was found between the blood pressure in lying supine onthe ground and in standing in the Kume Island deep ocean water, and the musculecirculations were also similar, the water pressure was likely to lie within safetrange.

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The purpose of this study is to evaluate feasibility of a large-scale deep oceanwater (DOW) pumping-up/distribution system. In this paper, total CO₂emission for two types of the DOW pumping-up/distribution systems, land-based andfloating-type, are assessed in their life cycle. The results of the assessmentsshow thatthe CO₂emission from DOW storage system is largest at initialstage. At operational stage, the CO₂emission from shuttle tanker fuelis quite large, and dominant in the total CO₂emissions.

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Acceleration of oceanic phytoplankton production by enriching oligotrophic surface seawater with eutrophic deep ocean water has becoming a recent desirable subject in order to achieve sustainable fisheries as well as contributing to possible absorption of carbon dioxide in the atmosphere to slow down global warming andefficient resource utilization of deep ocean water for multiple-purposes. Beforemaking actual operation of ocean fertilization, prior prediction of the probableeffects is required by means of field experiments and numerical simulation model. In this study, parameters and the applicable values for the model estimation of fertilization effects of deep ocean water on phytoplankton community in oligotrophic subtropical surface water were examined based on the data collected in out-door culture experiments using natural seawater samples. The addition of deep ocean water to surface seawater resulted 214-fold increase of chlorophyll aconcentration after several days of lag period. The specific growth constant of chlorophyll aconcentration increased at a rate of 0.3 days^-1 perμM-nitrate and the yield of chlorophyll awas 1.48μg/μM-nitrate. These changes were resulted from the increase of phytoplankton, mainly diatoms. Due to the preferential growth of diatoms, the relative abundance of nano- and microphytoplankton increased from 20% or less to around 80%, and the Si/N ratio ofthe nutrients, consumed with the increase in chlorophyll a concentration, amounted to 0.87.

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A new method for laying a deep-sea water intake pipe was developed. In this method, awater intake pipe is composed of steel pipe units linked by universal joints, and the pipe is laid by controlling buoyancy and tension of that.

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