本土化土壤沖蝕指標模式之建立

Development of Soil Erosion Index Model in Taiwan Watershed

10.29417/JCSWC.199809_29(3).0006

陳樹群(Su-Chin Chen)；簡如宏(Seasir Chien)；馮智偉(Jhy-Wei Ferng)；巫仲明(Chung-Ming Wu)

指標法 ； 土壤沖蝕 ； 泥砂產量 ； index model ； soil erosion ； sediment yield

中華水土保持學報

29卷3期（1998 / 09 / 01）

233 - 247

繁體中文

台灣山坡地集水區之地形陡峻，且降雨多集中於夏季之颱風雨，因此土壤沖蝕型態與美國大陸乾燥平坦之地型大不相同，故若採用USLE等公式，會發生沖蝕量高估之情況。本研究乃依台灣集水區地形，土壤，覆蓋，降雨及土地利用等五項因子，配合實測資料分析驗證建立本土化土壤沖蝕指標模式如下所示：沖蝕指標值公式SE -6x10^(-7)-AI^(5,12) for AI≦50 SE 0.233AI^(1.83) for AI＞ 50式中AI為沖蝕指標總值，SE為單位面積之沖蝕量（ton / ha）。以指標法估算沖蝕量時，僅需將各指標因子之條件，由各個指標值表格中找出適當之對應值，再據此求出所有指標值之總合，代入指標公式，即可估算土壤沖蝕量，此法簡易且可靠性亦高，可供水土保持計畫審議開發行為所使用。

With steep terrain and excessive rainfall, Taiwan is affected by severe soil erosion which is caused by typhoons and storms in the summer season bringing intensive rainfall and rapid flows. However, the soil erosion types are different from those in US which has mild slope and dry weather. The actual erosion is less than predicted by USLE model. Developing a soil erosion index model is the important goal of this research. Five factors, soil texture, rainfall type, land slope, land cover and land use, are included in this model. Soil factor is measured by K_m from the USLE model, and other factors are determined from local field data. The soil erosion index model yields: SE=6 x 10^(-7) AI^(5.12) for AI≦50 SE=0.233 AI^(1.83) for AI＞50 where AI is the total index value and SE is the soil erosion quantity (ton/ha). This soil erosion index model, after having been properly calibrated and verified, is rather useful150% in planning soil and water conservation or assessing soil erosion impacts.