By systematic researches, the concept of soil and water conservation validity involving into definition, effe ctive factors, appraising indexes and implementing way, was firstly put forward.

• 首次提出了水土保持有效性的概念，并对此进行了比较系统的研究，涉及到水土保持有效性的定义、影响因素、评价指标和实现途径等各个方面。