Urban green spaces, which are important for human and wildlife in the urban area, have changed into man-made spaces. Increased urbanisation has had and continues to have a negative impact on urban green spaces, and affects the urban microclimate as represented by ‘Urban Heat Island (UHI)’ phenomena. Especially, habitat fragmentation can be extreme within urban ecosystems, and fragments of natural vegetation may be too small or even too isolated to support some species. Therefore, the networks, which offer habitats and corridors that help conserve biodiversity, are also important to maintain the ecological services of a sustainable urban landscape, as well as total green area. However, there are rarely enough open spaces due to urban densification. This is why rooftops of buildings, which had not previously been regarded as spaces for planting for vegetation, have been utilised as a type of open space, and so green roofing has become one of the gradually developing fields of urban ecological engineering. This present paper aims to explore the potential of rooftops as habitats of urban wildlife comparing cases in Japan and UK, and pave the way for a preservation of urban biodiversity under restricted urban environmental conditions. As a result, it was suggested that Japanese green roof industries consider the concept of brown/biodiverse roofs instead of extensive roofs with sedum or lawn. At the same time, intensive roofs should be efficiently installed to provide ‘stepping stone’ in urban areas not having enough open space. If possible, however, to create habitats on the ground is more preferable than on the rooftop due to accessibility. Finally, if impervious spaces (e.g., concrete and asphalt) are replaced with pervious spaces (e.g., green area or brownfield), it is significant for not only urban biodiversity but also UHI.

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This paper is a review with regard to the past studies estimating forest stand structures using airborne light detection and ranging (LiDAR). The LiDAR, which has developed greatly since the 1990s, is an active remote sensing technology that directly obtains data inside the canopy, such as ground elevation, by penetrating the tree canopy; that is, it can acquire vertical, in addition to horizontal, information about the forest, unlike passive optical remote sensing technologies. LiDAR-based forest measurements have been developed mainly in Europe and North America, and have been conducted mainly over large-scale coniferous forests consisting of relatively few tree species, compared with broad-leaved forests consisting of many tree species. The first interest in the application of LiDAR to forest measurement was to determine terrain elevations. Among the forest structural variables, tree height has been most intensively focused on by LiDAR-based estimation. Other forest variables, such as crown diameter, biomass, timber volume, fractional cover, leaf area index, tree species, and three-dimensional foliage distribution, have been also estimated using LiDAR data. The recent interests in the LiDAR application to forest survey include generalization of estimation methods of forest structure, synergetic use with other types of data such as optical image, and wildlife habitat characterization. For the future, one solution of cost reduction of LiDAR data acquisition seems effective data use including collaborative partnership for data sharing and publication. It is important to establish methods estimating heterogeneous forest structure with high accuracy for operational use of LiDAR data.

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It has been two decades since the crisis of amphibians gathered attentions and triggered the intensifications of research on the reasons of declines and ecology of amphibians. The reasons for declines differ place to place and species to species but the main threats are the loss of wetland, habitat fragmentation and environmental pollution. In Japan, since the large part of natural wetlands has been lost, rice paddies and related areas have played important roles as substitute habitat for wetland species and supported rich indigenous ecosystems. The modernization of agriculture and increase of abandonment of farming however drastically changed these environments. Anuran species, especially pond-breeding frogs, are very common and representative of rice paddy ecosystems. Most of frogs are sensitive to environmental pollution and require both aquatic and terrestrial habitats to complete life cycle, they are considered bio-indicator of environmental changes of rice paddy area. For this paper, I focused on an endangered pond-breeding frog, the Nagoya Daruma pond frog (Anura: Ranidae, Pelophylax porosa brevipoda Ito, 1941), because its life history is closely linked to rice paddy areas. Because most of its natural habitat has been lost, and currently no population in natural habitat is known, for the conservation of the frog, it is vital to study the ecology in the areas. The main threats for the species are changes in yearly water management in rice paddies, improvements of drainage by agricultural modernization and hybridization between Pelophylax porosa nigromaculata. In this paper, I reviewed the situations of amphibians, the relationship between rice paddy area and frogs, conservation of frogs in agroecosystem and life history and ecology of P. p. brevipoda for discussing conservation of frogs in rice paddy area especially P. p. brevipoda.

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