摘要: | 爲求水土資源永續經營、經濟持續發展,臺灣應儘速建立一套土壤流失的推估模式,合理估算每年土壤流失量,提供國內水土保持工程設計的參考依據。因應發展將來土壤流失推估技術與方法的需求,已在標準土壤沖蝕試區,蒐集每場降雨相關氣象及水土流失數據及資料,用作驗證及修正臺灣地區適用的土壤沖蝕坡面模式,並訂定坡面沖蝕產砂模式所需的參數值包括:降雨土壤入滲特性;土壤表土結皮條件;細溝發育臨界水文條件等。更進行室內試驗,定出土壤表層抗剪強度與土壤合水量的指數函數,以利計算模式中坡面濺蝕分散量、細溝水流沖蝕力及水流輸移能力。驗證分析結果顯示初步研擬的土壤沖蝕坡面推估模式,已能適用於臺灣地區。
For further economic development and sustainable soil and water resources management, the establishment of a soil loss prediction model is urgently needed to accurately assess the soil erosion problem in Taiwan. Study results may provide essential elements for future design of soil and water conservation engineering works. Extensive field gathered data have been proven beneficial for developing the process-based soil loss prediction model suitable for application on steep slopes in Taiwan. A preliminary hillslope erosion model has been developed with the aid of a power function relationship between soil moisture and topsoil shear stress, as well as other model parameters such as infiltration characteristics, soil crusting factor and rill formation threshold. |