Effectiveness of functional zones in National Nature Reserves for the protection of forest ecosystems in China.

Protected areas (PAs) have been established worldwide to conserve biodiversity. However, the conservation effectiveness of different PA functional zones remains poorly understood. Here, we investigated National Nature Reserves (NNRs) in China to explore and quantify the conservation in their core, buffer, and experimental zones. We compared the area and proportion of forest loss for these functional zones during the period from 2001 to 2018. The results showed that the forest loss in NNRs showed a decreasing trend since 2011, indicating that NNRs reduced the forest loss. There was no significant difference of forest loss proportion (p = 0.42) between the core zones (0.60 ± 1.32%) and buffer zones (0.55 ± 0.88%), implying that their performance in forest conservation was similar. There was a significant difference between experimental and core zones as well as between experimental and buffer zones both in forest loss area and proportion (p ˂ 0.05). We confirmed that the proportion of functional zones significantly affects the conservation effectiveness, i.e., an improper proportion of core zones or buffer zones may lead to forest loss. Therefore, we suggest an optimal proportion of core and buffer zones at 30%-50% and 10%-40%, respectively. Overall, the effectiveness of functional zones in forest nature reserves was assessed on a national scale. The results of this study support the recent adjustment in the PA functional zoning system in China.