Toshiaki OWARI, Professor
・Cross-Appointed Faculty, International Program in Agricultural Development Studies (IPADS)
The University of Tokyo Hokkaido Forest, Graduate School of Agricultural and Life Sciences, The University of Tokyo
Contact information:
Phone +81 167-422111
>>EMAIL owari[at]g.ecc.u-tokyo.ac.jp
Professional Experience & Education
| 2025: | Professor, The University of Tokyo Forests, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan Professor (cross-appointed), Digital Spatial Society, The University of Tokyo, Japan |
|---|---|
| 2021: | Associate Professor (cross-appointed), Digital Spatial Society, The University of Tokyo, Japan Adjunct Associate Research Fellow, Experimental Forest, College of Bioresources and Agriculture National Taiwan University, Taiwan (~2025) |
| 2018: | Visiting Associate Professor, Department of Development and Sustainability, School of Environment, Resources & Development, Asian Institute of Technology, Thailand (~2018) |
| 2012: | Associate Professor, The University of Tokyo Forests, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan Visiting Associate Professor, Risk Analysis Research Center, The Institute of Statistical Mathematics, Research Organization of Information and Systems, Japan (~2013) |
| 2007: | M.S., Department of Forest Economics, Faculty of Agriculture and Forestry, University of Helsinki, Finland |
| 2006: | Instructor, Division of Environmental Resources, Research Faculty of Agriculture, Hokkaido University, Japan; Lecturer, University Forests, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan |
| 2000: | Ph.D., Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan |
| 1999: | Instructor, Division of Environmental Resources, Graduate School of Agriculture, Hokkaido University, Japan |
| 1997: | Instructor, Department of Forest Science, Faculty of Agriculture, Hokkaido University, Japan |
| 1995: | M.S., Department of Forestry, Graduate School of Agriculture, Hokkaido University, Japan |
| 1993: | B.S., Department of Forestry, Faculty of Agriculture, Hokkaido University, Japan |
Discipline
Forest Science
Research themes
- Close-to-nature forest management and silviculture
- Data-driven forest management using spatial technologies
- Single-tree management for high-value timber species
Study example
- Climate change can have a significant impact on forests by altering disturbance regimes such as insect outbreaks and windstorms. As an effective method for climate change adaptation and mitigation, close-to-nature silviculture is increasingly gaining attention worldwide. It is a type of management approach, in which the intrinsic processes of forest ecosystems are considered as highly important. Partial cutting with natural regeneration is typically used for maintaining multi-aged mixed forests with structural and spatial heterogeneity, which are assumed to be more resilient against ecological disturbances than even-aged mono-specific forests. As a unique application of close-to-nature silviculture in northern Japan, the stand-based silvicultural management system has been used since 1958 at the University of Tokyo Hokkaido Forest. We explore the applicability of innovative geospatial technologies such as light detection and ranging (LiDAR) and unmanned aerial vehicle (UAV) photogrammetry for silvicultural management planning.
- Unmanned aerial vehicle (UAVs) and digital photogrammetric techniques are two recent advances in remote sensing technology that are emerging as alternatives to high-cost airborne laser scanning (ALS) data sources. We demonstrated that fixed-wing UAVs are capable of efficiently collecting image data at local scales and that UAV imagery can be effectively utilized with digital photogrammetric techniques to provide detailed automated reconstruction of the three-dimensional canopy surface of mixed conifer–broadleaf forests. We confirmed the potential of UAV imagery when combined with ALS digital terrain model to capture the fine scale spatial variation of merchantable volume and carbon stock in living biomass in uneven–aged forests subjected to silvicultural practices and natural disturbances over time.
- High-value timber species play a significant economic role in forest management. In uneven-aged mixed conifer-broadleaf forests in northern Japan, monarch birch (Betula maximowicziana), castor aralia (Kalopanax septemlobus), and Japanese oak (Quercus crispula) are important producers of high commercial value timber. We examined the potential use of unmanned aerial vehicle digital aerial photogrammetry (UAV-DAP) in combination with long-term forest measurement dataset for single-tree management of high-value timber species. Our results indicated that the use of remote sensing data and resource assessment techniques could facilitate the retrieval of individual tree information of high-value timber species and could support single-tree management systems. Further, our results confirmed the applicability of UAV-DAP data in practical forest measurement of high-value timber species.
Primary papers
Huiqing Pei, Toshiaki Owari, Satoshi Tsuyuki, Takuya Hiroshima, Danfeng Hong (2025) Combined gated graph convolution neural networks with multi-modal geospatial data for forest type classification. International Journal of Applied Earth Observation and Geoinformation, 136: 104372 (doi: 10.1016/j.jag.2025.104372)
Jeyavanan Karthigesu, Toshiaki Owari, Satoshi Tsuyuki, Takuya Hiroshima (2024) Improving the estimation of structural parameters of a mixed conifer–broadleaf forest using structural, textural, and spectral metrics derived from unmanned aerial vehicle Red Green Blue (RGB) imagery. Remote Sensing, 16(10): 1783 (doi: 10.3390/rs16101783)
Nyo Me Htun, Toshiaki Owari, Satoshi Tsuyuki, Takuya Hiroshima (2024) Mapping the distribution of high-value broadleaf tree crowns through unmanned aerial vehicle image analysis using deep learning. Algorithms, 17(2): 84 (doi: 10.3390/a17020084)
Toshiaki Owari, Sangjun Im, Biing T. Guan (eds.) (2022) Long-term Monitoring and Research in Asian University Forests: Understanding Environmental Changes and Ecosystem Responses. 130pp, CRC Press, Oxon, United Kingdom (ISBN: 9781032172354)
Kyaw Thu Moe, Toshiaki Owari, Naoyuki Furuya, Takuya Hiroshima (2020) Comparing individual tree height information derived from field surveys, LiDAR and UAV-DAP for high-value timber species in northern Japan. Forests, 11(2):223 (doi: 10.3390/f11020223)
Sadeepa Jayathunga, Toshiaki Owari, Satoshi Tsuyuki (2018) Evaluating the performance of photogrammetric products using fixed-wing UAV imagery over a mixed conifer-broadleaf forest: Comparison with airborne laser scanning. Remote Sensing, 10(2): 187 (doi: 10.3390/rs10020187)
Toshiaki Owari, Koji Okamura, Kenji Fukushi, Hisatomi Kasahara, Shinichi Tatsumi (2016) Single-tree management for high-value timber species in a cool-temperate mixed forest in northern Japan. International Journal of Biodiversity Science, Ecosystem Services & Management, 12(1-2): 74-82 (doi: 10.1080/21513732.2016.1163734)
Shinichi Tatsumi, Toshiaki Owari (2013) Modeling the effects of individual-tree size, distance, and species on understory vegetation based on neighborhood analysis. Canadian Journal of Forest Research, 43(11): 1006-1014 (doi: 10.1139/cjfr-2013-0111)
Toshiaki Owari, Naoto Kamata, Takeshi Tange, Mikio Kaji, Akio Shimomura (2011) Effects of silviculture treatments in a hurricane-damaged forest on carbon storage and emissions in central Hokkaido, Japan. Journal of Forestry Research, 22(1): 13-20 (doi: 10.1007/s11676-011-0118-3)
Toshiaki Owari, Yoshihide Sawanobori (2007) Analysis of the certified forest products market in Japan. European Journal of Wood and Wood Products, 65(2): 113-120 (doi:10.1007/s00107-006-0166-0)
Toshiaki Owari, Heikki Juslin, Arto Rummukainen, Tetsuhiko Yoshimura (2006) Strategies, functions and benefits of forest certification in wood products marketing: perspectives of Finnish suppliers. Forest Policy and Economics, 9(4): 380-391 (doi:10.1016/j.forpol.2005.10.005)