結皮對地表沖蝕發展之影響

Effect of Soil Crusting on Overland Erosion Development

高敬倫(Ching-Lun Kao)

指導教授 ： 吳嘉俊

國立屏東科技大學/工學院/水土保持系所/碩士(2012年)

https://doi.org/10.6346/NPUST.2012.00281

摘要

本研究以野外田間沖蝕試驗為基礎，結合試驗過程中拍攝之全區正射影像分析，探討結皮特性、發展歷程與土壤沖蝕的關係，及不同坡長對土壤結皮的影響等，並針對結皮發展過程中發生的現象進行詮釋。最後將上述結果，構築為一完整的結皮發展論述。
由研究結果得知，結皮遭受沖蝕之後會產生一形似階段之現象，而經由距離與範圍量化之後發現，其發展結果與試驗區之坡長有關、階段之階數及深度與逕流流路有直接關係、位於逕流匯流口之階段，都會較厚，且有跳階的現象。由田間試驗所得之數據顯示，降雨強度對於結皮之沖蝕影響較大。

關鍵字

土壤結皮 ； 沖蝕機制 ； 影像判識

並列摘要

The objective of this study is to investigate the soil surface crusting; its characteristics, how surface crusting develops, and how crusting affects soil erosion. Field experiments were conducted to measure the total soil loss by storm. Orthophotos that covered the entire runoff plots were taken and images were post processed to quantify the progress of crust development. The results were then used to find the correlation between slope lengths, and a treatise of crust development was obtained.
The field observations as well as the images registered in series of orthophotos indicate that terrace-like structures were formed when surface crusts were damaged by erosion mechanism. The distance to the downstream boundary and the extent of the development of the terrace-like structures were affected by the slope length. The numbers of terraces and the step sizes were founded to be related to the runoff routes. Terraces located at the confluence of runoff routes appeared to possess greater step as well as order jumps, of which, a terrace can skip the sequential order and leaps from low-order terrace to higher order. Total soil loss obtained from field measurement also indicated that rainfall intensity has greater impact on the erosion of the crusts.

並列關鍵字

Soil crusts ； Erosion process ； Image interpretation

參考文獻

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