To understand the impact of deer population growth and deer-proof fences on bumblebee communities, we investigated the bumblebee community structure and plant types that bumblebees visited inside and outside deer-proof fences constructed 14 years ago in Oku-Nikko, Japan. We also reviewed reports on the bumblebee communities before the deer population increased and immediately before the fence was built. Cluster analysis was used to divide the bumblebee communities into two groups. Group I included the area before the deer population increased, in which Bombus beaticola predominated, and involved high rates of visits to the flowers of plants preferably eaten by deer. Group II included the areas inside and outside the fences, immediately before their establishment. Predominant Group II species included B. honshuensis, with high rates of visits to flowers of plants that were not preferred by deer. These findings suggest that no remarkable recovery of the bumblebee community has been achieved 14 years after building the deer-proof fences. This might be because of a decrease in plant underground organs and buried seeds or a decline in plant fertility resulting from bumblebee population changes due to deer overabundance. Thus, a long time is required to restore both the plant and bumblebee communities after deer exclusion.

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As part of a program for the conservation of wetland plants in Japanese lowland paddy regions, we compared plant species richness and taxonomic composition among four land-use types on the Echigo Plain: cultivated paddy fields, fallow (including abandoned) paddy fields, soil-lined irrigation canals, and concrete-lined irrigation canals. Species compositions were similar across cultivated fields. Total species richness was lower in these fields than in fallow fields and soil-lined irrigation canals. Species of annual and winter-annual herbs (including endangered taxa) occurred regularly in cultivated fields. Species composition varied among fallow fields, which supported the highest species richness across land-use types. Some of the fallow fields provided important habitat for species (particularly perennial herbs) that were rare on cultivated land. Concretelined irrigation canals contained very few species, but soil-lined canals supported a diversity of taxa. Most floating-leaved and submerged species occurred only in soil-lined irrigation canals. Thus, we suggest that wetland plants unique to each land-use type should be preferentially conserved, thereby enhancing overall diversity across the whole region.

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Acer pycnanthum (Sapindaceae), a dioecious tree endemic to Japan, is designated as vulnerable on the Japanese Red List. In this study, we evaluated the status and demography of the largest known population of this maple in the Iwayado habitat in Sendanbayashi, Gifu Prefecture. All individuals of A. pycnanthum > 15 cm in girth at breast height (gbh) were mapped, and their size, stem number, flowerring, and sex were recorded. In total, 785 and 44 individuals of A. pycnanthum were observed in two subpopulations located 150 m apart: Area A (7.5 ha) and Area B (0.9 ha), respectively. The subpopulation in Area A showed an inverted J-shaped size distribution, indicating sustainable regeneration. In contrast, the subpopulation in Area B showed a multi-peaked size distribution having few young individuals, suggesting that population decline will follow the death of extant individuals. Repeated past human activities such as clear cutting may have created large open spaces for successful regeneration of A. pycnanthum. While most A. pycnanthum populations are small and declining due to poor regeneration, the continuous monitoring of population dynamics in the Iwayado habitat is important in assisting management strategies for sustainable conservation of this species.

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I investigated the distribution of the piscivorous fish Opsariichthys uncirostris uncirostris (classified as vulnerable [VU]) along 45 km of the southwest shoreline of Lake Biwa, central Japan. The species was observed at 58 of 175 sites studied. Although it mainly occurred north of Otsu City, i.e., the Shiga District, I also found the species in the city's densely populated southern districts. I used generalized linear mixed model (GLMM) analysis to examine the probability of adult and immature O. u. uncirostris occurrence (binary data) in terms of several explanatory variables: lake substrate type (sand, gravel, and other), watercourse shape (surface stream, subterranean stream, dried-up stream, and shore), the presence of reeds, embankments, and/or trees along the watercourse, and the season (spring, summer, autumn, and winter), with site as a random effect. The GLMM indicated a positive effect of sandy substrate on O. u. uncirostris presence. I used permutational analyses of variance (PERMANOVAs) to examine the presence/absence of adult and immature fish in terms of the same explanatory variables as the GLMM, with the exception of season. This analysis also showed that the substrate significantly affected O. u. uncirostris occurrence. Thus, sandy substrates should be protected to promote O. u. uncirostris inhabitance.

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We investigated the population structure of trees in the coastal forests 3 months after the Great East Japan Earthquake to understand the impact of tsunamis. To clarify the impact on types of damage to trees, a belt transect (540 × 40 m) was set perpendicular to the shore line, transecting both the sand dune and back marsh. Species name and diameter at breast height (DBH) were recorded for both live and dead trees > 5 cm in DBH. Major types of damage were classified as "leaning", "stem breakage/bending", "prooted", and "floating", and recorded for all trees. Species names were also recorded for living trees ≤ 5 cm in DBH. Elevations in the belt transect were obtained using a digital elevation model. Pinus thunbergii was the most numerous, followed by P. densiflora, Prunus spp., and Robinia pseudoacacia. All types of damage were observed in the back marsh, while uprooting and floating were almost absent on the sand dune. Seedlings and saplings of deciduous broad-leaved trees were observed in the back marsh. Those of P. thunbergii were observed both on the sand dune and in the back marsh. Continued monitoring of these biological legacies will be required for establishing multifunctional coastal forests.

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The spatial patterns of plant diversity and environmental heterogeneity were analysed in a coastal forest, 2 years after the severe tsunami caused by the 2011 Great East Japan Earthquake in Japan, to gain basic knowledge for managing coastal forest after a severe disturbance. The 〜60.5-ha study site was divided into four patch types: 1) tall forest with mostly remaining trees (TR); 2) tall forest with mostly fallen trees (TF); 3) low forest with mostly fallen trees (LF); and 4) back marsh remaining post-tsunami (BM). First, the species composition differed conspicuously among patches. There were significantly more woody and coastal herbaceous species in TR and LF patches than in other patches. The species composition differed conspicuously between TR and TF patches, although environmental conditions were similar before the tsunami, i.e., 65.2% of the 92 observed species were restricted to either patch. A survey revealed that four endangered or vulnerable species (Swertia diluta var. tosaensis, Penthorum chinense, Patrinia scabiosaefolia, and Dianthus superbus var. longicalycinus) were restricted to TF patches. The number of species in 1 × 10 m quadrats was positively related to the difference between the highest and lowest elevations in each quadrat; this gave an index of tall trees. Our results suggest that the tsunami increased both the β-diversity (among-patch diversity) and α-diversity (within-patch diversity) of the coastal forest.

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We examined the relationship between coastal plants and microtopography damaged by the Tohoku tsunami of 2011 in a sandy beach to coastal forest ecotone in Minami-Gamou region, near Sendai Bay, Japan. We surveyed three transects on sandy beach and one in coastal forest 28 months after the tsunami. Plant composition was similar between the coastal forest and sandy beach, but plant density was significantly higher in the forest than on the beach. Coastal plants likely established in the coastal forest from the seedbank or from rhizomes extending from the beach, as the ground underlying the coastal forest rose after the tsunami. Furthermore, alien herbs and shrubs dominated in the higher elevations of the coastal forest. This suggests that coastal vegetation will develop into forests in the future. Meanwhile, coastal plant diversity was high in the sandy beach depression zone, but this zone will be destroyed by sea wall development. Consequently, it is important to maintain diverse microtopography to conserve coastal plant diversity in this region.

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Much of the coastal forest along Sendai Bay was severely disturbed by the huge tsunami resulting from the Great East Japan Earthquake (March 11, 2011). To evaluate changes in coastal forest vegetation after the tsunami, we implemented a phytosociological survey in four different microhabitats-remnant-forest, disturbed-forest, bare-soil, and moist-soil-between 2011 and 2013. In 2011, pioneer species such as Chenopodium acuminatum Willd., Oenothera laciniata Hill, and Phytolacca americana L. dominated the forest floor in all microhabitats except moist-soil areas. We propose that these species originated from seeds in sand deposited by the tsunami. However, in 2013, biennial and perennial herbs (Erigeron Canadensis L., Erigeron sumatrensis Retz. and Solidago altissima L.) increased while pioneer species declined. In addition, forest plants (e.g., Liriope minor (Maxim.) Makino, Lonicera japonica Thunb.), which began growing before the tsunami, increased in both disturbedand remnant-forest areas. Seedlings of tall tree species, such as Pinus thunbergii Parl., P. densiflora Siebold et Zucc., Prunus verecunda (Koidz.) Koehne, also emerged in bare-soil areas. These results suggest that the coastal forest vegetation is recovering autonomously in the study area. On the other hand, exotic plants (e.g., Robinia pseudoacacia L., Amorpha fruitcosa L.) were also vigorously resprouting from below-ground roots, and may inhibit the recovery of native species.

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The Great East Japan Earthquake disturbed coastal regions facing the Pacific Ocean. Subsequent infrastructure reconstruction in the coastal region of southern Sendai Bay has now become a major threat to biodiversity. The recovering coastal forest zone has been artificially filled and re-planted with pine trees. Seawalls are being reconstructed by strengthening remnant structures. Here, we present five lessons learned through studying the reconstruction process. 1) Monitoring and evaluation of biodiversity before disaster strikes can provide indispensable data for prioritizing actions after ecological devastation. 2) Development of methodologies and policies for rapid environmental assessment are essential. 3) The effects of large, infrequent disasters on biodiversity should be studied. 4) Scientists should prepare procedures for dealing with scientificproblems that arise at the time of disaster and afterwards. 5) Development of policies and technologies for ecosystem-based ('green') infrastructure reconstruction is important for enlightened management of disaster effects on human populations and for biodiversity conservation.

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