We analyzed the effect of genotype and planting density on the growth patterns of height and diameter at breast height (DBH) and the efficiency of indirect early selection targeting on the low planting density using stem analysis data obtained from a test site composed of 6 cultivars and 3 planting densities (5,000, 3,000, 1,500 trees/ha) at stand age 28. The growth pattern of height was mainly affected by genotype, but the effect of planting density was small. The growth pattern of DBH was affected by both genotype and planting density. Our results showed the importance of selection of the genotype of seedlings for the control of growth in plantations of Sugi. The results of genetic evaluation obtained at general planting density (3,000 trees/ha) could be applied for the prediction of genetic performance of growth traits at different planting densities. Approximately 15 years would be required to obtain 80％ of genetic gain at stand age 28 with the plantation of 1,500 trees/ha according to the test results obtained at the plantation of general planting density (3,000 trees/ha).

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Black locust shows seed heteromorphism producing both non-dormant and dormant morph. This study examined the ratio of both morphs for each tree in relation to its size and distribution along a river. The percentages of non-dormant seeds highly varied between individuals but order of them was rather consistent between two consecutive years. This suggested that there are individuals that are likely to produce more dormant seeds while others produce more non-dormant seeds. The trees with higher percentages of dormant seeds tend to occur at upper stream along the river side, and vice versa. Many larger individuals tend to produce higher percentages of dormant seeds. However, smaller individuals tend to produce higher percentages of non-dormant seeds, even though there were also trees with lower percentages. Therefore, the ratio of both morphs couldn’t be explained only by an age of the tree or the size. To produce non-dormant seeds would be advantageous, since they can rapidly expand population by immediate germination and establishment on the newly created open sites at downstream. On the other hand, most of elder trees tend to shed dormant seeds forming soil-seed-bank which contributes to recover following disturbances. In conclusion, seed hetromorphism in Black locust attributes to rapid expansion of this species at riverbed.

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The characteristics of soil terpenoid emissions are poorly understood; thus, the spatial variation needs to be evaluated. We measured the spatial variations in soil α-pinene emissions using the soil chamber method on the floor of a red pine (Pinus densiflora Sieb. & Zucc.) forest. The distance from the trunk and the dry weight (DW) of leaf litter were not associated with α-pinene soil emissions. A positive relationship was detected between the DW of leaf litter and α-pinene emission rate from the A layer after removing the A₀ layer. A clear linear relationship was observed between the DW of well-mixed leaf litter and α-pinene emission rate from the litter. These results suggest that terpenes on the soil surface affected the high α-pinene emission rate from the soil, particularly during spring.

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Several Pinus parviflora var. parviflora populations in the Kanto district were thought to be regionally endangered and affected by decreased population size and habitat fragmentation. In order to develop conservation strategies, this study aimed to assess the genetic diversity and mating system of their populations, including three endangered (Boso, Tanzawa, and Hanazono) and one intact (Koshinzan) populations, using four nuclear microsatellite (SSR) loci. The level of genetic diversity of mature trees of the Boso and Tanzawa populations was similar to that of the intact population. Analysis of the mating system revealed that the proportion of selfed progeny of saplings in the endangered populations was higher (34.2–65.5%) than that in the intact population (15.1%) and that the endangered populations had a lower effective number of pollen donors (1.7–5.6) compared to the intact population (15.6). Multilocus heterozygosity (MLH) analysis indicated that the frequency of low MLH was high in saplings less than 5 years old. The mode of MLH increased with the life history process. These findings suggest that mature trees in the endangered populations mostly retain high levels of genetic diversity, but the decline in the number of mature trees has resulted in increased selfing and decreased selfed saplings possibly due to inbreeding depression.

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The purpose of this research was to clarify the consciousness of Japanese tourists regarding the Xinjiang Uygur Autonomous Region, China, for tourism promotion. We distributed a questionnaire to Japanese tourists who were visiting Shirakami-Sanchi and Hiraizumi, which are famous tourist resorts in the Tohoku district of Japan. Our investigation yielded the following findings: 1) Japanese tourists expect to enjoy both natural scenes, and to be appraised of local history and culture. 2) Japanese tourists intending to visit parts of Asia expect to enjoy contact with local people, and a sense of “discovery” and “stimulation” during their foreign travel. 3) When shown photographs of four tourist resorts in Xinjiang Uygur Autonomous Region, they considered that in addition to nature, history and culture, there should be amenities for Japanese tourists.

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In this article, we summarized current data processing streams of change detection algorithms using time series satellite images and their applications to tropical forests. We also discussed challenges and perspectives of forest monitoring using time series satellite images in tropical regions. Time series satellite images have been utilized to acquire detailed information about forest changes. After Landsat data became freely available, change detection algorithms using time series satellite images were developed. These developments have encouraged the employment of time series images to capture forest changes. In the case of tropical regions, frequent cloud cover and fast vegetation recovery after disturbance are the major problems when we use change detection with time series satellite images. However, developments of algorithms utilizing dense time series data or data fusion with other sensor enable us to detect forest change using time series satellite images with sufficient accuracy in tropical regions. While the forest change detection with time series satellite data has the potential to play an important role in tropical regions, there are still problems that have to be overcome such as insufficient ground data and lack of data fusion methods with other sensors.

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