Changes in sediment erosion rate in the Azuma River basin after the Hokkaido eastern Iburi earthquake in 2018
Changes in sediment erosion rate in the Azuma River basin after the Hokkaido eastern Iburi earthquake in 2018
复制标题
2018年北海道胆振东部地震后东川流域泥沙侵蚀率变化
DOI：
10.1088/1755-1315/1136/1/012027
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Yamada Tomohito J
中科院分区：
文献类型：
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作者：
Miyazaki Kotaro;Hoshino Tsuyoshi;Shimizu Keita;Shrivastava Sourabh;Yamada Tomohito J
2018年的北海道东伊武里地震在日本北岛北海道的东川流域诱发了最大规模的山体滑坡。本研究使用通用土壤流失方程（USLE）估算了地震前后东川流域的泥沙侵蚀速率。结果表明，整个流域的潜在泥沙侵蚀速率比震前增加了8-29倍。沉积物侵蚀率增加的主要原因是滑坡导致的森林砍伐，这造成了整个流域13%的裸露土地面积。此外，根据实测降雨资料计算了降雨年际变化对泥沙侵蚀率的影响。结果表明，地震后泥沙年侵蚀速率最小值超过震前最大值，说明地震后泥沙年侵蚀速率明显高于震前。这些研究结果表明，为了评估东川流域的泥沙侵蚀风险，有必要预测和监测植被恢复，考虑降水的年际变化。
The Hokkaido Eastern Iburi earthquake in 2018 induced the largest landslide over the Azuma River basin in Hokkaido, the north island of Japan. This study estimated the sediment erosion rate over the Azuma River basin using the universal soil loss equation (USLE) for the pre-and post-earthquake conditions. The results showed that the potential sediment erosion rate from the entire basin increased by 8–29 times more than the pre-earthquake condition. The primary cause of the increase in sediment erosion rate was deforestation due to the landslide, which generated 13% of the bare land area in the entire basin. In addition, the influence of interannual variability of rainfall on sediment erosion rate was calculated from observed rainfall data. As a result, the minimum annual sediment erosion rate after the earthquake exceeded the maximum before the earthquake, indicating that the post-earthquake sediment erosion rate is substantially higher than the pre-earthquake rate. These findings suggest that in order to assess the sediment erosion risk over the Azuma River basin, it is necessary to predict and monitor the vegetation recovery, considering the interannual variability of rainfall.