A novel framework for evaluating the effect of vegetation restoration via grazing exclusion by fencing: A case‐study from the Qinghai–Tibet Plateau

Abstract

AbstractGrazing exclusion by fencing (GEF) has been implemented to prevent the deterioration of grassland ecosystems in China since the beginning of this century; meanwhile, the effects have attracted widespread attention from the academic community. However, due to the simultaneity of different factors, it is difficult to separate the effect of different policies from natural resource endowments and identify the independent role of each policy. In this study, a novel framework was established based on spatiotemporal statistics. First, an indicator‐denoted vegetation restoration potential achievement degree (VRPAD) was introduced to lessen the impact of resource endowment conditions. Second, a double‐difference model of both space and time was developed to reflect the net improvement of VRPAD brought by GEF. The case study showed that 15 out of the 17 fenced‐off enclosures achieved positive VRPAD growth since the GEF implementation, while only 58.8% showed a much faster improvement or a slower degeneration than their adjacent areas. It was also found GEF effect presented apparent administrative differences in terms of spatial distribution. The number of effective fences accounted for 75% in Mami Town, but it was 0 in Chabu Town. It is concluded that the role of GEF may be overestimated, multi‐pronged approaches are more conducive to vegetation restoration, and strengthening grassroots management and self‐policing of fences is important to improve GEF efficiency. This research provides a novel framework for distinguishing policy effect and is expected to inspire new ideas and methodological support for policy formulation and evaluation.