Abstract: The effects of forest cover change on water yield, a hotspot as well as a difficult issue in the fields of forestry, ecology and hydrology, still exist great debate. Observations of numerous watershed experiments that have been conducted for a century throughout the world also vary greatly and remain controversial. Here, based on the observations of globally published paired-watershed experimental and the time-trend result, we comprehensively presented the divergent opinions on the effects of forest cover change on water yield and analyzed the potential underlying mechanism. After that, we further summarized four aspects which need to be emphasized in future studies:1) to develop carbon and water coupling research at multiple scales; 2) to develop multiple sites and cross-regional integration research; 3) to concentrate on hydrological and ecological processes, mechanism and modeling; 4) to strengthen the cross-penetration and integration of different disciplines and technical fields studies.

Key words: vegetation cover change, runoff, watershed, ecohydrology