Polydora cornuta complex (Spionidae; Polychaeta) is commonly found in the muddy bottom layer of areas such as trade ports. In Japan, P. cornuta complex has been found to be unevenly distributed in Fukuyama port, Dokai bay, Hakata bay, and Tokyo bay. The present study was conducted to characterize the P. cornuta complex population in Fukuyama port by analyzing a partial region of the mitochondrial cytochrome oxidase subunit 1. Genetic variation of the population living in Fukuyama port was quantified, and 6 haplotypes were observed from 8 individuals. Furthermore, comparisons of DNA sequences with Maine, Florida, California and New Zealand that are available in the DNA Data Bank of Japan revealed the Fukuyama species has a close lineage with the California and New Zealand groups, but not with the Maine or Florida group. This is the first report on molecular phylogenetics of Polychaeta Spionidae in Japan.

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We estimated the vertical profiles of leaf area density (LAD) of Japanese maple and camellia canopies in a woody area by using portable scanning lidar. 3D point cloud data on the canopies were collected by lidar from several points on the ground. Appropriate selection of ground points allowed the targets to be well scanned in spite of the presence of several trees around them. LAD profiles were computed by using the voxel-based canopy profiling method. The maximum and mean LAD values were 1.68 and 0.93 m² m^-3 for the Japanese maple canopy and 0.94 and 0.41 m² m^-3 for the camellia canopy. Leaf area index values were 1.61 and 3.35 m² m^-2, respectively. Comparison of these LAD estimates with actual measurements taken in volumes of 2 m³ within the canopies gave percentage errors of -14.2% in the Japanese maple canopy and -16.4% in the camellia canopy.

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In order to analyze the psychological effect on high school students when they grow plants with cooperation with each other, two separate experiments were carried out for 36 third graders and 122 first graders in high school from May to December in 2009. Analysis of psychological states was carried out using two psychological ratings, SD (the Semantic Differential Method) and POMS (the Profile of Mood States), along with the measurement and analysis of electroencephalogram and questionnaire about the effect of the plants. In the first experiment, the corridor was divided into three areas. The first area was named ‘Unit of good friend’, the second ‘Unit to meet strangers’ and the third, ‘Unit of 1 person’. Each area's students grew the plants in their areas for 7 weeks. The results were as follows. The students in the first units (Unit of good friend) had more affection and comfortable feeling toward their plants than the other two groups. They also had more time for communication with each other while growing their plants as they had to cooperate with each other rather than taking care of them alone. In the second experiment, the students were divided into five groups, ‘Unit of 4 boys’, ‘Unit of 4 girls’, ‘Mixed unit of boy and girl’, ‘Unit of 1 boy’ and ‘Unit of 1 girl’. Each unit took care of its plants for 7 weeks. The results were as follows. ‘Unit of 1 boy’ and ‘Unit of 4 girls’ had more affection and comfortable feelings toward their plants. Boys appreciated the sentiment and atmosphere of plants in their room, whereas girls appreciated the comfort of the space in the room more and communication was also promoted.

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The objective of our study is to clarify the optimum irradiation conditions for the efficient cultivation of Euglena, in order to increase the yields. First, we measured the blinking light response curve of photosynthesis and investigated the effect of the blinking cycle on the photosynthesis, using red light emitting diodes (LEDs). Second, we determined the photosynthetic photon flux density (PPFD) value at which the photosynthetic efficiency was maximum. Here, we measured the difference in the photosynthetic rate of Euglena using red LEDs under blinking and continuous light conditions. In cases where the blinking cycle was 1.0 x 10^-3 s, there was no difference in the photosynthetic rate of Euglena between the two conditions. On the other hand, at a PPFD value of 35 μmol·m^-2·s^-1, the photosynthetic efficiency was the highest. In cases where the PPFD value ranged from 0 to 200 μmol·m^-2·s^-1, the photosynthetic rate increased rapidly. Then, it increased slightly and reached a saturation point at a PPFD value of 400 μmol·m^-2·s^-1.

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