摘要
简要分析了核示踪法在土壤侵蚀研究中的应用现状 ,并以稀土元素 (REE)示踪法为例 ,结合不同坡度、不同流量的室内放水冲刷模拟试验对坡面侵蚀产沙垂直分布特征进行了研究 ,研究结果表明 :在坡度较小的情况下 ,坡面各不同部位的相对侵蚀量沿下坡方向呈现出先减小后增大的趋势 ;在坡度较大而流量较小的情况下 ,坡面各坡段的相对侵蚀量与坡度较小的情况相似 ,当流量较大时 ,坡面各不同坡段的相对侵蚀量呈现出随坡长的增大而减小的趋势。但坡面最下端坡段的相对侵蚀量总是随着冲刷历时的延长而呈现出下降趋势 ,而其余各坡段的相对侵蚀量则呈现出缓慢的波动式上升。试验结果还表明 REE示踪法可以比较满意地说明坡面侵蚀过程中的泥沙来源情况 ,是一种研究坡面侵蚀产沙特征的有效方法。
Rare earth element (REE) tracing method is a new method to study soil erosions. It is widely used in the studying of the laws of erosion vertical distribution on land slope due to its accuracy. Based on the reviewing of the REE(Rare Earth Element) trace method and the present application of the method to the study of soil erosion. The tracing and INAA technology, the calculation of the erosion results, as well as its application in the soil erosion on slope were introduced. Combined with the runoff scouring method under the different slope gradients, different flow discharges and REE(Rare Earth Element) technology, the temporal and spatial variation rules of the sediment yield on the land slope were studied in this paper. The results showed that the relative erosion mass of the different section along the slope decreases at the beginning and increases at the later period. Experiments on the steeper slope with a smaller flow discharge indicated that the relative erosion mass of the different section along the slope is similar to that on the gentle slope. With the larger flow discharge, the relative erosion mass decreases with an increase in the length of slope. The temporal variation of sediment yield on the slope is that the relative erosion mass at the bottom section of the slope decreases with experimental time increase, while the relative erosion mass on other section increases fluctuantly.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2003年第2期65-69,共5页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金委员会重大项目"江河泥沙灾害形成机理及其防治"(59890 2 0 0 - 5)
