著者

岡谷 隆基

出版者

日本地図学会

雑誌

地図 (ISSN:00094897)

巻号頁・発行日

vol.60, no.2, pp.12-18, 2022-06-30 (Released:2023-09-14)

参考文献数

20

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Author carried out this study for clarifying topographical characteristics and verifying scale of natural phenomenon in the places indicated by the “Shizensaigaidenshohi” (monument of natural disaster). The followings are the major results.1) Clarification of topographic characteristics where a “Shizensaigaidenshouhi” stands or indicates.Most of the place where “Shizensaigaidenshouhi” (monument of natural disaster, simply referred to as “the monument” in this article) stands or indicates, locates not only in very low areas (e.g. flood plain), but also in a little bit higher areas (e.g. natural levee). This is because the monument building was not reasoned by heavy rainfall or flood itself, but by the damage of lives or properties which exist in higher areas.2) Verification of scale of natural phenomenon which brought disaster where a “Shizensaigaidenshouhi” stands or indicates.Past flood depth inferred by the description of the subject monuments was slightly low or equal to that estimated by modern hazard map. In early and middle of the 20th century, many flood disaster happened and the relevant monuments were built thereafter, but in the late 20th century, the number of severe floods which recorded in the monuments decreased. However, frequency of heavy rainfall is increasing recently. This suggests flood disasters likely to be recorded in the monuments would occur again in the near future.These results show that location of a “Shizensaigaidenshouhi” stands or indicates prefers a little bit higher areas as people lives more in such areas compered to lower land and also show that past flood depth inferred by the description of the subject monuments was compatible with that estimated by modern hazard map.Map symbol “Shizensaigaidenshohi” is recently introduced to the basic topographic maps, and the new topographic maps therefore provide people with new map reading experience, which might raise people's awareness of disaster prevention as existence of “Shizensaigaidenshohi” is deeply relating to topography.