Application of modified USLE slope factors on steep terraced field

• Main Authors: Tzu-Hao Wang, 王子豪
• Other Authors: Rong-Song Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/29317793143734984533

碩士 === 國立中興大學 === 土木工程學系所 === 98 === The function of terraced paddy fields included conserving water in the farmland, deferring the formation of the flood peak and runoff and keeping soil from running off, all of which contributed to the soil and water conservation as well as water purification. However, most studies in Taiwan focused on paddy fields and upland field on the hillside, while only few studies researched on terraced paddy fields. Therefore, this project selected the rainfall events in experimental terraced paddy field during the year 2005 and 2008, and collected the quantitative data of rainfall, runoff and soil erosion under different cultivation types. This study aimed to explore the relationship between the rainfall factors and soil erosion of the terraced paddy fields on the hillside under the condition of cultivation, fallow and planting green manure. In this study, power regression was utilized to explain the correlation of runoff, rainfall erosivity, total rainfall kinetic energy and maximum rainfall intensity in 30 minutes. It was found that the individual runoff and soil erosion were most highly correlated. Furthermore, this study modified the slope factor of the Universal Soil Loss Equation and estimated the soil erosion of the experimental paddy field by this modified equation. However, since the outcome might be overestimated, this study tried to find out the relationship between the estimated and measured values in the rainfall events under different cultivation types. Finally, this study formulated the modified factors under cultivation, fallow and planting green manure, and the corrected estimates turned to more accurate.