Forest management and biodiversity: the critical role of landscape composition and forest plantations in bird diversity

The expansion of agricultural land and forest plantations has led to significant global changes in the landscape, which have the potential to adversely impact birds, which play a vital role in ecosystem functioning. The intensive management leads to a decline in bird abundance and richness, especially among forest species. This study examines the effects of different forest management strategies, including short rotation (Eucalypt plantations), medium rotation (Pine plantations), and forests without intervention (unmanaged Native forests), on bird species and functional richness, phylogenetic diversity, abundance, and species composition at different landscape scales, considering the forest dependency of bird. Bayesian hierarchical models were created to identify the drivers (forest management, vegetation, forest characteristics, and surrounding landscape) influencing it. The results demonstrated that Eucalypt plantations harboured lower species richness, phylogenetic diversity and abundance, and a different species composition than both Native forests and Pine plantations, being particularly evident among characteristic forest species. In contrast, Native forests provided optimal conditions for both characteristic forest species and other species, highlighting their indispensable value for biodiversity conservation. However, Pine plantations supported a mixture of both types of species, which did not reach the diversity values observed in Native forests. Furthermore, the surrounding landscape has been demonstrated to exert a fundamental role in shaping bird diversity (taxonomic, functional and phylogenetic) across multiple landscape scales. The presence of native forests enhanced bird diversity at all landscape scales, whereas eucalypt plantations had a detrimental effect. It is therefore suggested that more sustainable management strategies be implemented, with a focus on bird’s diversity conservation.