Neoempheria ferruginea is a pest fly in sawdust-based cultivation of shiitake mushrooms, Lentinula edodes. We investigated the effect of food supply (5% sugar solution or distilled water) and temperature (15, 20, or 25°C) on adult longevity, number of eggs oviposited, and hatching success. Adults reared on sugar solution lived longer (7.0∼31.4 days) than adults reared on water (3.0∼6.9 days). Females reared on sugar solution oviposited more eggs (131.7∼281.8) than did females reared on water (63.7∼152.2). Females began ovipositing one day after eclosion under all rearing conditions, but the peak of oviposition (90% of eggs) was earlier for water-reared flies (3∼4 days after eclosion) than for flies reared on sugar solution (5∼9 days after eclosion). Thus, the presence of a sugar source increased adult longevity and egg number in N. ferruginea. Flies reared at 20°C laid significantly more eggs than did flies reared at either 15 or 25°C. The hatching success of eggs reared at 15°C was significantly lower than that of eggs reared at 20 or 25°C, with a range of 29.2∼69.4%.

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The objective of this case study was to quantify changes in the relationship between rainfall and direct runoff from the early period (1935∼1946) to the late period (2000∼2011) in the Ananomiya watershed, Ecohydrology Research Institute of The University of Tokyo Forests. The early period was defined as an initial stage of forest restoration on a denuded hill, whereas the late period was defined as a transition stage of forest succession and an initial stage of soil recovery. When total rainfall was 200, 300, and 400 mm, the estimated total direct runoff during the early period was 16.0, 25.8, and 33.5 mm, respectively, higher than that during late period. The difference in estimated direct runoff between the early and late periods was clear when the initial water condition was dry or the rainfall intensity was high. When the initial watershed condition was dry and when rainfall was 200, 300, and 400 mm, the estimated direct runoff during the early period was 19.1, 29.1, and 36.6 mm, respectively, higher than that during late period. When the rainfall intensity was high and when total rainfall was 200, 300, and 400 mm, the estimated direct runoff during the early period was 36.3, 56.7, and 71.3 mm, respectively, higher than that during the late period. However, when the soil condition was wet or the rainfall intensity was low, no difference was detected in direct runoff between the early and late periods.

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We evaluated forests that are vulnerable to oak wilt, and prospects of regenerating the damaged trees. Most canopies of Quercus crispula trees died within 10 years after the spread of the oak wilt, while the canopies of Q. serrata survived by approximately 40% or higher rate. The average vegetation coverage at canopy layers in a severely damaged forest was 28% in Q. crispula dominated stands and 47% in Q. serrata dominated stands. Furthermore, a small number of tree species in the sub-canopy layers of Q. serrata dominated stands. Thus, Q. crispula dominated stands are expected to lack canopy layers for many years, while canopy layers can be expected to be restored in Q. serrata dominated stands. However, regeneration by seedlings may not occur in either of the oak stands, because Camellia japonica and other evergreen broad-leaved undergrowth species will keep occupying the shrub layers. Also, since most trees that have died from oak wilt have toppled down within 5 years, the falling of dead trees may cause problems to the infrastructure, such as blocking of roads and cutting of the electric wire.

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Somei-yoshino, one of the most famous flowering cherry cultivars, has been planted widely in Japan. To allow for appropriate planting that considers the genetic diversity of neighboring wild flowering cherry populations, the range of pollen-mediated gene flow between Somei-yoshino and related wild species was investigated. We also considered the factors that affect inter-specific gene flow. In a paternity analysis using six nuclear simple sequence repeat (SSR) markers, 95% of the pollen donors crossing with Somei-yoshino were identified as trees within 300 m of the maternal tree. Conversely, the farthest pollen flow from Somei-yoshino detected in seeds sampled from wild flowering cherries was approximately 190 m. In the bidirectional pollen-mediated gene flow, flowering phenology was an important factor in the gene flow pattern based on generalized linear models. Note, however, that flowering phenology differs among years and species, which may affect the range of hybridization between Somei-yoshino and wild flowering cherries.

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We aimed to assess the effects of vegetation modification caused by deer on birds. We examined the effects of deer density on vegetation modification and the relationship between the species composition of bird communities and the vegetation structure in 3 areas (8 plots/area) with different deer densities in Oku-Nikko, central Japan. The number of living trees, number of tree species, and basal area of living trees decreased significantly with an increase in deer density, suggesting that deer density contributes to vegetation modification. Using TWINSPAN, the 24 plots were divided into groups A (high deer-density) and B (low deer-density) and 32 bird species were divided into groups 1∼4. Bird species with a preference for open habitats tended to belong to group 1 and were observed primarily in group A plots. Bird species with a preference for foraging in shrubs tended to belong to group 4 and were observed primarily in group B plots. Tree-hole nesting birds tended to belong to group 2 or group 3 and were observed equally in group A and group B plots. Discriminant analysis indicated that the plot classification by TWINSPAN could be interpreted according to the number of shrub trees, sub-canopy trees, and shrub species. These results indicate that vegetation modification because of high deer density may contribute to changes in the species composition of bird communities.

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The coastal forest and town damage in Iwate prefecture, Japan, following the 2011 Tohoku Earthquake Tsunami were surveyed at 14 sites by field observation and aerial photographs. Of the sites, 10 were almost destroyed by the Tsunami; however, four towns sustained only slight damage, despite the destruction of adjacent coastal forest and breaching of the sea wall. The common factor of the four towns was the large distance (≧about 600 m) to the coast line. Furthermore, two towns were located at a high elevation (≧18 m) and had expansive open spaces, such as paddies, at lower elevations. On the other hand, two towns located at lower elevations (≦10 m) were protected by a thick coastal forest zone (about 1 km) and a sea wall. These findings suggest that land use designation and the existence of coastal forest are important for protecting coastal towns from a tsunami.

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The genetic diversity and genetic structure of the natural and breeding populations in Hiba (Thujopsis dolabrata var. hondae) were investigated using five nuclear microsatellite markers. DNA samples were collected from seven natural populations in five prefectures (Hokkaido, Aomori, Iwate, Niigata, and Ishikawa) and three breeding populations in three prefectures famous for Hiba breeding (Aomori, Niigata, and Ishikawa). The genetic diversity such as allelic richness and expected heterozygosity between natural and three breeding populations were similar. In the results of STRUCTURE analysis and NJ tree, natural and breeding populations in Niigata and Ishikawa Prefectures were genetically differentiated from other populations. The NJ tree reflected the geographic location of each population, which suggested that the three breeding populations were selected from the natural populations in each prefecture. The detected genetic structures might be derived from the difference of their establishment process.

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For 17 Japanese cedar (Cryptomeria japonica D. Don) clones planted in a progeny test plantation, we investigated the male flower setting four times during 17 years in 26 to 42-years-old trees, particularly examining mast years. The 17 clones were 15 plus trees and 2 local varieties. As a result, the clones with high male flower setting as of 26 years old showed the tendency for male flower setting to be high, to 42-years-old. The clones with low male flower setting showed a low tendency to 42-years-old. Therefore, estimation of the male flower setting of Japanese cedar clones became clear as of 26 years old. Moreover, results suggest that the change of male flower setting accompanying aging of the 17 investigated clones is not uniform and that male flower setting varies with heredity. In addition, as of 42-years-old, the clones to which the male flower setting index became smaller than the clones selected as a Japan cedar with little pollen existed in the clones expected to be stable also by aging while male flower setting has been low, therefore, it was thought that clones with little pollen might be chosen more.

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