Characteristics of flow production and sediment production of iPinus tabulaeformis/ithrough artificial rainfall simulation

摘要

In order to know well the relationship between vegetation and water in North China, especially Beijing, with exceptional water resources, we studied the characteristics of flow production and sediment production under different rainfall intensities by artificial rainfall simulation device. Results showed that increase of rainfall intensity would prolong the whole process of flow production, and vegetation on the slope would delay that process. Within the same duration, total runoff volume of each runoff plot and rainfall intensity had significant linear relationship. When vegetation kept unchanged, runoff velocity increased significantly with the increase of rainfall intensity, and owing to the formation of low permeable layer, the velocity increased fiercely during the early 3 minutes, reached stable at 10 - 15 minute. With the same rain intensity, total sediment yield decreased with rise of vegetation coverage, but increased obviously with rise of rain intensity and effectiveness of controlling sediment about 1 m x 1 m Pinus tabulaeformis stand decreased firstly and then increased, while that about 1.5 m x 1.5 m Pinus tabulaeformis stand kept decreasing. Since the tags with A, B and C for 0.42 mm/min, 0.83 mm/min, 1.29 mm/min, order of sediment concentration of wasteland plot was B > C > A, and 1 m x 1 m Pinus tabulaeformis plot B > A > C. Through this study, some suggestions were expected to be provided for water balance of Beijing area and certain basis for construction of shelter forest.