Do strictly protected areas protect vulnerable local tree species better than human land use? Disentangling conservation value from biodiversity value

Abstract

A growing number of conservationists argue that effective management of human modified ecosystems is preferable to protecting undisturbed forest ecosystems. Hence, this study evaluated the efficiency of the two alternatives for the conservation of vulnerable tree species by comparing the distinctiveness of species composition, species richness, and evenness of local assemblages. The study was conducted in Mafhela and Thathe Vondo Forest Reserves, South Africa. The result showed that all land-use regimes in Mafhela became distinct from each other, lost species, became uneven, and tree species were replaced by shrubs along the land-use gradient compared with State-protected indigenous forest. In contrast to Mafhela, the State-protected indigenous forest in Thathe Vondo was not exceptionally distinct from the other land-use regimes. The contrast reflects the difference in the condition of the forest landscape complexity of the two Forest Reserves that moderate the resilience and stability of the ecological process in a continuously changing environment. Our study implies allocating the limited resources to reinforce State-protected indigenous forest in Mafhela, accompanied by restoration of the whole landscape, and would be a preferred conservation strategy. In contrast, in Thathe Vondo, investing the limited resources in the whole landscape's sustainable management would be preferable. In conclusion, our study posits that the approach of “one size fits all” conservation measure, without considering the influence of forest landscape condition in the resilience of local assemblage, misguides the efficient allocation of limited global conservation resources to avert local extinction of vulnerable tree species of primary forests.