Do policy-designated buffer zones shape land cover trajectories around protected areas? Evidence from fifteen South African National Parks

Buffer zones are intended to facilitate the management of anthropogenic pressures surrounding protected areas; however, empirical evidence regarding characteristics of these pressures before and after buffer zone implementation remains limited. This study investigates impervious land cover surfaces (used as a proxy for land-use changes associated with urban development) and cropland coverage to assess how land cover change patterns have evolved within the buffer zones of fifteen South African National Parks from 2000 to 2022, using the GLC_FCS30D dataset. We found that policy-designated buffer zones shape land cover around PAs only to a limited extent. Following designation, development-related trajectories generally remained stable or slowed, while agricultural trajectories showed no significant change. The study compares trends in two buffer zone types, i.e., Priority Natural Areas (PNAs) and Viewshed Protection Areas (VPAs), before and after implementation to describe directional changes over time. Trends before and after implementation were quantified using segmented regression analysis. Most PNAs demonstrated stable impervious surface trajectories with no significant change in growth rate post-implementation, whereas several VPAs exhibited deceleration in impervious surface growth rate. Conversely, cropland trajectories were more variable across buffer types, exhibiting both accelerations and decelerations in growth rates, indicating that agricultural expansion remains a more dynamic and influential land-use driver within buffer zones. Shifts in cropland, therefore, remain a key concern and likely require greater policy focus and stronger coordination across conservation, planning, and agricultural sectors.