Stream buffer strips are located between the terrestrial ecosystem and the aquatic ecosystem

which are also the important composition of stream ecosystem.This paper emphasizes the introduction of six ecological functions of buffer strips

that is

species heaven

nutrient source

river bank stabilization

water quality amelioration

landscape value and harmful impact alleviation.However

disturbances caused by human activities to stream buffer strips become serious due to a great increment in the land for construction and transportation.Therefore

there is an urgent need in scientific rehabilitation and management.For this reason

we present three basic principles of scientific management of stream buffer strips as the guidelines for the rehabilitation and construction of stream buffer strips in different grades in different areas.By taking the Nansha River located in Haidian district of Beijing for an example

we illustrate the functions of stream buffer strips and the scientific management principles.