Keynote SpeechProtecting coastal zones with forests:
Toward the development of disaster risk reduction (DRR) technology
Toyohiko Miyagi
The construction of adaptation measures to climate change, such as global warming,has become a real challenge in the present age. The coastal zone is (1) a place where theland-ocean interaction system is expressed and is also (2) a place where different typesof nature coexist, such as intertidal zones, shallow seas, and coastal lowlands. (3) Fromthe perspective of human survival, it is necessary to guarantee the stability of the place.
In addition, (4) there is a concern that the effects of climate change will be diverse andintense. The mangrove forest and its land, like a forest ecosystem of the sea, has
attracted attention for its resourcefulness and land conditions and has become the targetof a wide range of human activities such as environmental destruction, economicactivities, and urbanization symbolized by the creation of shrimp ponds. On the otherhand, it has played a role in attenuating the tsunami force in the 2004 Indian OceanTsunami. The mangrove forest area has also focused on proposals for new concepts
such as climate change adaptation and REDD+. It has become a new policy target forutilization, like forest disaster prevention and mitigation functions. From the standpointof a mangrove forest, one might think, “Humans are very self-rationalizing creatures in
the way they treat mangroves.”
For those of us who have been studying and researching mangrove ecosystems as afield science subject and who have spent much effort to obtain precise data in deepmud, the dramatic development of sensing technology is an opportunity that marks anew era. The accuracy of sensing, three-dimension digitization, low cost of tools, andopen source are unexpected developments. This progress may lead to furtherdevelopment in two significant ways. First, the accuracy of observation of forests andtrees will be enhanced in a revolutionary way. The ability of individuals to handle highperformance equipment at their discretion and to generate and process data will pave theway for the visualization, quantification, and shared understanding of "reality,"
something that many people have felt itchy to do in the past. Second, the acquisition ofdigital high-precision data on forests, landforms, and trees, which are the backbone ofecosystems, will advance the "numerical analysis" related to the growth, decline, anddestruction limits of forests and trees, as well as land, water, and sediments.
Our sense tells us that the time has come to "turn tacit knowledge into evidence-basedknowledge.” Sensing technology is a fundamental technology for observation andmeasurement. By making good use of it, we can apply it to, for example, “quantificationof the composition of forests and sediments,” “evaluation of changes in the location anddistribution of forests,” and “construction of the best matching scenario for green andgrey infrastructure.” In this way, we believe that we will bring convincing results indeveloping and applying disaster prevention and mitigation measures in the coastalzones.

Dr. Toyohiko Miyagi
Professor Emeritus Tohoku Gakuin University /Chief Engineer, Advantechnology Co. Ltd.
Toyohiko Miyagi was born in 1951. He graduated from the Faculty of Letters,
Tohoku Gakuin University, in 1974 and received his doctorate degree from the Facultyof Science, Tohoku University, in 1980. He became an assistant professor in the Facultyof Letters at Tohoku Gakuin University in 1980. In 2005, he moved from a professor atFaculty of Letters to a professor in the Department of Regional Studies, Faculty of
Liberal Arts, Tohoku Gakuin University, retiring in 2019.
On the Surveying day, June 3, 2017, the Geospatial Information Authority of Japan(GSI) presented him with a certificate of appreciation for his distinguished service. His
major research interests include natural geography, landforms of hilly slopes, landslide
landforms, and geo-ecology of mangrove forests. He has also been promoting naturalgeography and disaster prevention education using hazard maps and GIS in recentyears.