應用地面光達於風化泥岩層沖蝕觀察之研究

Application of Terrestrial LiDAR on Mudstone Regolith Erosion

楊啟見(Ci-Jian Yang) ； 林俊全(Jiun-Chuan Lin) ； 鄭遠昌(Yuan-Chang Cheng)

《中華水土保持學報》 46卷3期 (2015/09) Pp. 150-157

https://doi.org/10.29417/JCSWC.201509_46(3).0003

摘要

本研究利用人工降雨機模擬高強度的降雨事件，並使用地面光達測繪數值高程模型，數值高程模型用於重建侵蝕過程並量測邊坡侵蝕量，並連結侵蝕地形變化與累積降雨量的關係，實驗地點選在臺南市龍崎區水土保持教室區域內之泥岩邊坡。研究結果顯示：風化泥岩層受水力侵蝕的過程，可分為四個階段，第一階段：侵蝕型態以片狀侵蝕為主，侵蝕範圍大但總侵蝕量低；第二階段：侵蝕型態以紋溝侵蝕為主，侵蝕量與侵蝕速率快速增加；第三階段：單一水流流路形成，紋溝間侵蝕量已經大幅減少，泥塊崩落之次數與規模皆有下降；第四階段：邊坡進入穩定期，泥裂幾乎不存在，單一紋溝的規模增大，偶伴隨零星泥塊崩落，侵蝕量來源為紋溝侵蝕和泥塊崩落所致。

關鍵字

風化泥岩層 ； 水力侵蝕 ； 人工降雨機 ； 地面光達 ； 紋溝

並列摘要

This study aims to record the process of mudstone slope erosion during high intensity rainfall events using an artificial rain simulator and Terrestrial LiDAR. Further, we connect the erosion pattern and accumulated rainfall. Field Experiments are carried out in Longqi, Tainan. The results show the water erosion process of mudstone regolith can be divided into four stages. (1): The main erosion pattern is recognized as sheet erosion, because it has a large erosion range but low erosion volume; (2): When the erosion volume and rate increase rapidly, the erosion process enters the rill erosion stage; (3): As rill develops, the surface flow merges into a single water flow path, and the effect of the inter-rill erosion decreases. At the same time, the number and scale of the collapse also decline; (4): While the mud-cracks almost disappear, the erosion pattern enters the stable stage. At that time, the single rill becomes wider and deeper. In this stage, the main erosion process can be thought of rill erosion and collapse which occur occasionally.

並列關鍵字

Mudstone regolith ； water erosion ； artificial rain simulator ； terrestrial LiDAR ； rill