台灣西北部土壤沖蝕性及流失量之估算

SOIL ERODIBILITY AND SOIL LOSS OF NORTHWESTERN TAIWAN

萬鑫森(S.S. Wann) ； 黃俊義(J. I. Hwang)

《中華水土保持學報》 12卷1期 (1981/07) Pp. 57-67

https://doi.org/10.29417/JCSWC.198107_12(1).0003

摘要

土壤冲触性指數表示土壤冲蝕性之高低。本文設定土壤冲蝕性指數K值小於0.20以下者爲低蝕性土壤在0.20-0.40間者爲中蝕性土壤，在大於0.40以上者爲髙蝕性土壤。苗栗地區山坡地大多爲低蝕性土壤。新竹地區則以中蝕性土壤爲主，桃園地區以低蝕性土壤居多，中蝕性土壤次之，台北地區因取樣地點較少，但就現有資料研討，屬於低或中蝕性土壤。土壤冲蝕性指數小並不能保證冲蝕不會發生，因之許多地方雖然是屬於低蝕性土壤，但由於坡長太長或管理欠周，致土壤流失量仍然超出可容許流失量。凡表二中有此情形者宜加強水土保持工作，以維持該地區之永久農業。

並列摘要

Soil erodibility is usually used as an indication of the degree of easiness of a soil to be eroded. In this paper, we define that a soil is of high erodibility if its K-value is greater than 0.40; medium erodibility, between 0.20 and 0.40, and low erodibility if K-value is below 0.20. By this definition, we found that soils at Miao-Li are largely low in crodibility; those at Hsin-Chu, medium in erodibility. Most part of Tac Yuan soils are low in erodibility and some are medium in erodibility. Three of the five Taipei soils belong to medium erodibility, the other two are low in erodibility. Attempts were also made for estimating the amount of soil loss by using these some soils with low erodibility there were still greater soil losses than permited partly due to too long in slope length and partly due to poor in management. Soil conservation practice should be conducted in these areas for the permanent agriculture.