公告事項

學術活動

Flat View
By Year
Monthly View
By Month
Weekly View
By Week
Daily View
Today
Categories
By Categories
Search
Search

[演講公告]Landslide impacts on sediment dynamics in mountainous rivers after large earthquake and typhoon events: A sediment connectivity approach

講者:林穎東 博士候選人( Department of Geography at the Durham University)
講題: Landslide impacts on sediment dynamics in mountainous rivers after large earthquake and typhoon events: A sediment connectivity approach
時間:2024年1月8日(一) 10:00-11:00
地點:地理502
演講摘要:Small mountainous rivers (SMRs) produce about 40% of the world’s sediment discharge from land to ocean. The dominant source of this sediment is earthquake and typhoon-driven landslides. It is widely accepted that earthquake-induced landslides tend to locate at hillslopes, while typhoon-induced landslides tend to cluster at hillslope toe areas. Differences in landslide location determine the connectivity of landslide sediment sources to the river network. Therefore, understanding when and where earthquake and typhoon-driven landslides occur, and the pathways and timescales over which these sediment sources are connected to river channels can help us determine the relative controls of earthquakes and typhoons on sediment discharge in SMRs. This study aims to understand the different impacts of earthquake and typhoon on landslide distributions and the sediment discharge regime by using Landsat imagery within Google Earth Engine and inventory maps from Forestry and Nature Conservation Agency (FNCA), Taiwan to delineate 21 event-induced landslide maps between 1996 and 2019, which includes the 1999 Chi-Chi earthquake (M_w=7.7) and typhoon Morakot in 2009 ( >3000 mm of rainfall). These landslide inventories were then used to explore changes in spatial patterns of earthquake and typhoon-driven landslides over time, and to explore variations in landslide connectivity to the river network. This study also compared the annual sediment discharge with different domains’ landslide volumes to investigate the implications for post-event sediment transports.

Monday, January 08, 2024, 10:00 - 12:00
講者:
演講大綱:
講者簡介:
學術召集:
附件:


Hits : 233 

Back