Invasive alien plants have encroached and outcolonized many native species in almost all Japanese river floodplains in recent years. Sicyos angulatus is one of the most notorious invasive alien lianas. To select the effective season for exterminating S. angulatus, S. angulatus colony is explored seedling dynamics of S. angulatus in the Doki River floodplain from May to July 2020. Germination of seedlings of S. angulatus were started from early May in the part of the study area, and it gained momentum in July after beginning the rainy season. Many seedlings were dead around four weeks after germination, specifically, 59%, 78%, 38% of seedlings were dead respectively that germinated in May, June, July. The results of the model selection in generalized linear mixed models revealed that the rate of seedling death was determined by litter thickness and sky view factors. Almost seedlings that located a suitable site to survive were germinated in July. It was concluded that early August is the best season for exterminating S. angulatus in Doki River.

The species composition and habitat condition of the alpine desert (Dicentro-Stellarietea nipponicae Ohba 1969) on the northern part of the Ushiro-tateyama mountain range were investigated. Based on species composition, the Dicentro-Stellarietea nipponicae vegetation in this region was classified into 6 associations, 2 communities, and 2 subassociations.

On the leeward slope, Saxifragetum merckii idsuroei, Cardaminetum nipponicae and the Polygonum nakaii community are established on rectilinear to concave slopes, Veronico-Polygonetum weyrichii is established on rectilinear to convex slopes, and the Draba shiroumana community is established on convex slopes. Sedo rosei-Saxifragetum bronchialis funstonii, Dicentro-Violetum crassae are established on the convex slope on the windward side. Cerastio-Minuartietum vernae japonicae is established on the convex slope on any aspect. Most of the vegetation units were found on gravels, Sedo rosei-Saxifragetum bronchialis funstonii and the Draba shiroumana community were mainly found on rock shelves. The Polygonum nakaii community and Cerastio-Minuartietum vernae japonicae were found in serpentine areas. The Draba shiroumana community was found in limestone areas.

　In this region, the presence of Saxifrago-Cardaminetalia nipponicae could be explained by slope aspect and slope type. Alliances and vegetation units depended on more specifically defined environments, such as the stability of surface gravels and soil chemistry in the serpentine and limestone areas for the Minuartietalia vernae japonicae of this region

Various types of swamp woods dominated by the Japanese alder (Alnus japonica) are occasionally found in wetlands occurring in the cool and warm-temperate zones of the Japanese Archipelago. The vegetation of these Japanese alder swamp woods is azonal and they are a terminal community maintained under certain natural environmental conditions. The authors reviewed the phytosociological vegetation units (i.e., syntaxa) and reorganized their vegetation systems based on the phytosociological data previously published. These alder woods occurring in several habitats (waterside-marshes, fens, spring-wetlands, and back-swamps) were classified into six associations in the cool-temperate zone and three associations in the warm-temperate zone. These syntaxa were unified in three alliances (Fraxino mandshuricae-Alnion japonicae, Fraxinion japonicae, and Ligustro obtusifolii-Alnion japonicae) belonging to the order Alnetalia japonicae and to the class Alnetea japonicae.

Spectral irradiance in the tree canopies of Syzygium malaccense and Mangifera indica was measured 10 years after planting on the campus of the Center for Superior Studies of Novo Aripuanã, Amazonas State University, Brazil. S. malaccense had a cylindrical tree form, with dense foliage and no gaps, whereas M. indica had a more rounded shape with some gaps between the leaves. The parameters of light quantity in terms of photosynthetic active radiation (PAR), photosynthetic photon flux density, and illuminance were larger in S. malaccense than M. indica according to absorption/transmittance in the PAR wavelength. A similar difference was also found in the ratios between red and far red and between PAR and near infrared, suggesting that areas immediately under S. malaccense received a larger amount of infrared light. Moreover, the fraction of sky that is visible also showed a similar difference between the species, suggesting that light quantity is dependent on this variable, whereas quality is dependent on how the leaves overlap. Both phenomena were traced back to the differences in tree form between the two species. These results offer a foundation for agroforestry aimed at cultivation of vines, shrubs, and low-rise fruit trees under canopy layers with different tree forms.

We surveyed broad-leaved tree species grown as potential natural vegetation in the environmental protection forest surrounding the Kosaka mine in Akita Prefecture, Japan. Based on measurements of tree height and basal diameter, growth behavior was examined over the 10-year period since planting. There were large differences in survival rates between species, with Quercus serrata and Quercus mongolica var. grosseserrata showing remarkable survival and growth, and Prunus spp. showing low rates of survival. In terms of vegetation structure, Q. mongolica var. grosseserrata and Q. serrata formed the higher tree layer, with a forest structure based on tree species beginning to form. Growth behavior was examined at the four different types of survey site. In terms of the aspect ratio and volume index (D²H), Magnolia kobus and Fagus crenata exhibited plasticity in growth form depending on the planting site. Meanwhile, although Q. serrata and Q. mongolica var. grosseserrata showed differences in growth behavior between sites, they showed lower environmental selectivity compared with the other planted species. These findings suggest that both Q. serrata and Q. mongolica var. grosseserrata are suitable as dominant species of potential natural vegetation in this region.

Afromontane forests are rapidly disappearing in Africa, despite their discontinuous distribution and high biodiversity. Using the Miyawaki method, potential natural vegetation species were selected for restoration of Afromontane forest at the foot of Mt. Kenya. Monitoring has been conducted since planting to determine the growth performance and autoecology of the selected species. As many as 89% of the small potted seedlings were found to have survived 2 years after planting, reaching an average height of 176 cm and an average basal diameter of 21.9 mm. Markhamia lutea showed the greatest growth, whereas Olea europaea subsp. cuspidata, Podocarpus falcatus, and P. latifolius showed the slowest growth. P. falcatus had a more slender shape compared with P. latifolius in its native habitat. Prunus africana and Syzygium guineense had higher growth performance, whereas Ocotea usambarensis showed a stockier growth form. Furthermore, O. kenyensis was denser than O. usambarensis, suggesting that tree form is related to the width of the geometrical distribution in these Ocotea species. The Miyawaki method was successfully applied to forest restoration and useful ecological data on the Afromontane region in Kenya was obtained.

Various approaches are applied in forest surveys depending on their objectives, including inventory surveys and surveys based on measuring every tree. Phytosociological field surveys entail qualitative analyses of species and their dominance in each stratum, whereas cross-sectional schematics and physiognomic charts are often drawn to structurally and visually characterize forests. In this study, a phytosociological field survey was conducted and cross-sectional schematics were developed to analyse the height of each stratum, plant coverage, presence of an emergent layer, and number of species per survey section for various forests along the Great Rift Valley that cuts from the north to the south across the Republic of Kenya. Structural characteristics of forests in each areas were organised, including the Tinderet area where forest vegetation height is significantly tall; the Nairobi area, where the forest features low average tree height; Loita forest, where the tree layer has a high plant coverage with a large number of species per survey section; and the Marsabit and Mt. Kulal area, where the forest structure is characterised by five strata, including an emergent layer, but the number of species per survey section is significantly small. In Kenya, where the natural forest area is comparatively small relative to the area of the country, qualitative and structural recording of the few remaining areas of predominantly natural forests is of pressing concern with respect to the responses to various issues concerning forests, as well as to conservation and regeneration activities in the locally unique forests.