辽西低山丘陵区坡面暴雨产流产沙过程及水保效益

Runoff and sediment yield process by rainstorm and soil and water conservation benefit on slope surface in low mountain and hilly area of western Liaoning

基于辽西低山丘陵区二道岭小流域坡面径流和泥沙现场观测,研究暴雨条件下(7·28暴雨)6种不同水土保持措施的坡面产流产沙过程及水土保持效益。结果表明,在暴雨过程中,与裸地相比,耕作措施中的顺垄耕作缩短了初始产流时间,工程措施和林草措施延长了初始产流时间。不同措施的产流产沙过程和雨强变化趋势相似,横垄耕作的径流和含沙量与雨强存在延后现象。在暴雨条件下,以裸地作为对照,林草措施具有良好的减流减沙效果,而农业措施的顺垄耕作则增大了产流产沙作用,加剧了水土流失。

Based on the observation of runoff and sediment yield on slope surface of Erdaoling small watershed in the low mountain and hilly area of western Liaoning Province, the runoff and sediment yield processes and soil and water conservation benefits of 6 different soil and water conservation measures under rainstorm conditions(7·28 rainstorm) has been studied. The results show that: compared with bare land during the rainstorm, the initial runoff production time is earlier with longitudinal ridge measures, and is delayed by the engineering measures and forestry and grassland measures. The variation trend of runoff and sediment yield is similar to precipitation intensity under different measures. However, the processes of runoff and sediment content with cross ridge tillage lag behind the change of precipitation intensity. Compared with bare land, the forest and grassland measures have good effect in reducing runoff and sediment production, while the longitudinal ridge in the agricultural measures increases runoff and sediment production, exacerbating soil erosion.