Super typhoon Mangkhut resulted a large number of fallen tree in form of uprooting in university town of Shenzhen (UTSZ), which hadn't happened for years. This study conducted a survey about tree uprooting induced by super typhoon Mangkhut in UTSZ, aiming to reveal main reasons for tree uprooting in UTSZ. Species of fallen trees were recognized. Fallen direction and height of fallen tree were measured. Also depth and diameter of root-soil plate and dry density of soil beneath root-soil plate were measured. The results showed that many fallen trees with uprooting in UTSZ had relatively small volume of root-soil plate which was not able to offer sufficient anchorage to tree during typhoon. One of solutions to avoid this phenomenon is not to select tree species with shallow root depth. Ponding was found in many places where uprooting occurred in UTSZ. Increase of degree of saturation of soil induced by ponding can significantly decrease soil strength which is a major component of anchorage of tree. Thus we recommend to modify the poor drainage condition of soil in UTSZ. Degree of compaction of soil may not be a main factor related to tree uprooting in UTSZ.
How Small-volume Basaltic Magmatic Systems Develop: a Case Study from the Jeju Island Volcanic Field, Korea