The annual variation of runoff and erosion induced sediment yield gradually decreased along with the development of soil and water conservation work and the increase of forest and grass vegetation.

• 径流和侵蚀产沙的年际变化是随流域水土保持措施全面实施和小流域林草植被面积的增加，流域径流量和侵蚀产沙量逐渐减少。