Landslide identification and its risk assessment using high-resolution topographic data for natural environment conservation and disaster prevention

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K15257
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 25030:Disaster prevention engineering-related
• Research Institution: Hirosaki University
• Principal Investigator: Tsou Ching-Ying 弘前大学, 農学生命科学部, 助教 (40750055)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 地すべり / 危険斜面 / 発生履歴 / 変位計測 / 白神山地 / 詳細な地形データ / 森林環境保全 / 全地球測位システム

Outline of Final Research Achievements

Approaches are proposed to investigate the current landslide activity and reconstruct the spatial and temporal patterns of past landslide occurrence in the Shirakami Mountains, Japan. Microtopography of landslide is sometimes difficult to be identified, particularly under forest canopies, while high resolution topographic data can accurately represent terrain surfaces and is available to identify the microtopography. Besides, yearly horizontal landslide displacements of 3~13 cm were constrained using GNSS. Moreover, the spatial and temporal development of the landslides were reconstructed using tree-ring chronologies from 90 tilted deciduous broadleaved trees with various tree species over about 70 years.

Free Research Field

応用地形学

Academic Significance and Societal Importance of the Research Achievements

本研究は、白神山地における地すべりの発生場の素因としての地質・地形的特徴の調査や解析によって、発生場所の抽出への見通しを立て、そして、実際の地すべりの歪量や発生履歴を把握する手法を提案したものである。研究成果は、日本有数の地すべり地帯である世界自然遺産白神山地で、土地の動きからダイナミックな自然を読み解くことや森林環境保全や防災に重要な知見を与えるものといえる。